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1

Cotton, Peter Angus. "The hummingbird-plant community of a lowland Amazonian rainforest". Thesis, University of Oxford, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334213.

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Sanchez, Garduno Cecilia Maria. "Reproductive ecology of Brosimum alicastrum (Moraceae) in the neotropical rainforest". Thesis, Imperial College London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.419805.

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Gerber, Brian Daniel. "Comparing density analyses and carnivore ecology in Madagascar's southeastern rainforest". Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/36035.

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Madagascar is renowned for its biodiversity, but also for forest loss, fragmentation, and degradation, making it a global conservation priority. With few studies dedicated to Madagascarâ s carnivores, little is known about their ecology. My objectives were to 1) compare density estimation techniques applicable to enumerating rare and/or elusive carnivores, 2) investigate Malagasy carnivore distributions, abundance and density, and occupancy/use across four sites that vary in forest disturbance, and 3) explore temporal activity patterns of rainforest carnivores. I found the spatially-explicit-capture-recapture models were empirically superior, as they are flexible and account for spatial variation in detection probability and area estimation. I found both endemic and exotic carnivore composition varied among four rainforest sites: Primary, Selectively-logged, Fragments <2.5 km and Fragments >15 km from contiguous-primary rainforest. All endemic carnivores were present in the Primary and Selectively-logged rainforest, while endemic carnivore species richness decreased and exotic carnivore species richness increased in the fragmented forests. Malagasy civet (Fossa fossana) density ± SE was significantly less in the Selectively-logged compared to the Primary rainforest (1.38 ± 0.22, 3.19 ± 0.55 civets/km2, respectively); they were absent from both fragmented forests. Fossa (Cryptoprocta ferox) density ± SE was not different between the Primary and Selectively-logged rainforests (0.12 ± 0.05, 0.09 ± 0.04 adults/km2, respectively); a single animal was detected in the Fragments <2.5 km, while none were detected in the Fragments >15 km. Malagasy carnivores had varied temporal activity overlap (5.8-88.8%). C. ferox preferred crepuscular activity, but overall exhibited a cathemeral activity pattern.
Master of Science
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4

McCarthy, John F. "The fourth circle: A political ecology of Sumatra's rainforest frontier". Thesis, McCarthy, John F. (2000) The fourth circle: A political ecology of Sumatra's rainforest frontier. PhD thesis, Murdoch University, 2000. https://researchrepository.murdoch.edu.au/id/eprint/51163/.

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The Indonesian archipelago contains the world's second largest expanse of tropical forest and is a major world centre for biodiversity. Yet, Indonesia has one of the highest rates of deforestation. Central to this problem is the incomplete understanding of the institutional dynamics associated with deforestation at the district and village levels. This thesis is based on 12 months field research conducted during 1996-99 in Aceh, Sumatra. It examines how local institutional arrangements govern resource use in three communities (Sama Dua, Menggamat and Badar) within the Leuser Ecosystem, one of the richest expanses of tropical rainforest in Southeast Asia. The research focuses on the interaction of local customary {adat) village regimes, de facto district authority systems, and State policy. The thesis also considers the fate of biodiversity conservation projects that attempted to intervene in these areas. Customary (adat) institutional arrangements have mediated community access and use of a complex array of resources. These adat arrangements have adjusted to the characteristics of natural resources whose value fluctuates dramatically in response to markets elsewhere. The political, economic and ecological influences affecting these institutional arrangements varied with location and time. In each case local institutional arrangements have proved surprisingly resilient and dynamic, rapidly responding to fluctuating economic and political conditions in complex and locally specific ways. In the Sama Dua case, adat institutional arrangements have continued to adjust to the changing agro-ecological and economic conditions shaping the conversion of forest into productive agroforests. The forest here was less accessible to outside logging networks and local communities successfully maintained control against outside claims. As villagers have moved back to agriculture following the economic crisis of 1997, adat institutions have become more salient. Adat has also remained important in Menggamat. Here logging networks were able to co-opt community leadership and accommodate local customary arrangements by offering village actors a portion of the flow of benefits derived from logging community territory. In the third case of Badar, where villages were recently settled frontier communities, adat arrangements were less well established. Here, villagers formed a "growth coalition" with logging networks. The networks of political, economic and social exchange and accommodation evidenced in the second two cases eclipse both State and adat authority structures in governing local forest resources. This suggests that the explanation of environmental change necessarily has to focus on the matrices of power relations characteristic of these areas. In such circumstances, neither adat nor State institutional arrangements constitute viable resource management alternatives on their own. It is district webs of power and interest coalesced around logging and reaching out into the wider society that create the most serious obstacle to biodiverstity conservation, leading inexorably to environmental decline.
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5

Doust, Susan Jillian. "Seed and seedling ecology in the early stages of rainforest restoration /". [St. Lucia, Qld.], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18410.pdf.

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Davis, Andrew J. "The ecology and behaviour of rainforest dung beetles in northern Borneo". Thesis, University of Leeds, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395782.

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Nakabayashi, Miyabi. "Feeding ecology of three frugivorous civets in Borneo". 京都大学 (Kyoto University), 2015. http://hdl.handle.net/2433/199151.

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Ellwood, Martin David Farnon. "The ecology and diversity of the animal communities of a rainforest canopy epiphyte". Thesis, University of Cambridge, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.619518.

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9

Nagamitsu, Teruyoshi. "Community ecology of floral resource partitioning by eusocial bees in an Asian tropical rainforest". 京都大学 (Kyoto University), 1998. http://hdl.handle.net/2433/157161.

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本文データは平成22年度国立国会図書館の学位論文(博士)のデジタル化実施により作成された画像ファイルを基にpdf変換したものである
Kyoto University (京都大学)
0048
新制・課程博士
博士(理学)
甲第7176号
理博第1950号
新制||理||1049(附属図書館)
UT51-98-G105
京都大学大学院理学研究科動物学専攻
(主査)教授 山村 則男, 教授 堀 道雄, 教授 湯本 貴和
学位規則第4条第1項該当
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10

Ruitenbeek, Herman Jack. "Evaluating economic policies for promoting rainforest conservation in developing countries". Thesis, London School of Economics and Political Science (University of London), 1990. http://etheses.lse.ac.uk/19/.

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Economic policies are often suggested as mechanisms for promoting rainforest conservation in developing countries. To help decide whether international resources should be used to protect specific rainforcsts, the calculation of a "rainforest supply price" (RSP) is proposed. If protection is warranted, then empirical analyses explore the conditions under which selected policies within developing countries might be effective in protecting rainforests. Korup National Park in Cameroon contains the oldest rainforest in Africa and - as a haven for important endangered species- it is the subject of active international conservation efforts. A cost-bencfit analysis of a conservation project to protect Korup from increased land-use pressures suggests that it is not in Cameroon's interest unless a 5.4 million ECU inducement is transferred to Cameroon. Given the protection afforded, the transfer is equivalent to a RSP of 1060 ECU per km2 per year. Evaluations of six other tropical rainforest projects suggests that international donors made transfers having values ranging from 15 to 1575ECU per km2 per year. It is thus concluded that the inducements required are within a range which conservation interests are apparently willing to mobilise. To target inducements the provision of incentives in a "buffer zone" around a park is often believed to promote conservation. This is based on the hypothesis that increased incomes will draw individuals out of the park and will give them something better to do than exploit the park. A survey of 341 households around Korup was analysed in detail to test this hypothesis. Evidence suggests that economic development in the buffer zone would increase pressures on the park because: a) higher incomes would reduce emigration from the region and would thus cause greater population pressure on the Park; and, b) hunting effort increases as non-hunting income increases.
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11

Hausmann, Franziska. "The utility of linear riparian rainforest for vertebrates on the Atherton and Evelyn Tablelands, North Queensland /". Click here to access, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20050115.105740.

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Thesis (M.Phil.) -- Griffith University, 2004.
Facsimile of the author's original dissertation. Pagination of document: x, 121 leaves. Includes bibliographical references. Also available online via the World Wide Web.
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12

Keen, Eric Michael. "Whales of the rainforest| Habitat use strategies of sympatric rorqual whales within a fjord system". Thesis, University of California, San Diego, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10256131.

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The energy needs of rorqual whales (f. Balaenopteridae) govern their relationship to marine habitats during the foraging season. However, their cryptic foraging strategies and extreme feeding behaviors complicate our effort to identify and protect habitats “critical” for rorquals. What is the relationship between rorquals and their habitat, and how must that shape conservation strategies? I addressed this question in the case of sympatric humpback (Megaptera novaeangliae) and fin whales ( Balaenoptera physalus) in the marine territory of the Gitga’at First Nation in the Kitimat Fjord System of British Columbia. For three summers (2013-2015) I studied whales, their prey, and their environment aboard the RV Bangarang using oceanographic station sampling, systematic transect surveys, and opportunistic focal follows of whales (Chapter 1). Ocean sampling demonstrated the strong coupling of water features with offshore patterns in storm forcing and regional meteorology (Chapter 2). By combining these surveys with a long-term Gitga’at dataset, area humpback whales were found to practice a structured and persistent pattern in seasonal habitat use, which demonstrates how complex and habitat-specific a rorqual’s habitat use can be (Chapter 3). Both humpback and fin whales were found to respond to changes in krill supply in aggregative and behavioral thresholds that are set by a combination of intrinsic energetic needs and the context of local prey supply (Chapter 4). Associations with non-prey habitat features were markedly different in the two species (Chapter 5). Humpback distribution was more closely coupled to that of their prey and other habitat features, while fin whale distribution was driven broadly by site fidelity. Novel spatial analytics were used to identify the most probable environmental cues used by foraging whales (Chapter 6). Both species were found to be particularly sensitive to the depth of prey layers, which is governed largely by oceanographic features (Chapter 7). This coupling of habitat features and feeding performance influences the competitive dynamics of rorqual whales. The findings in this case study advance general theories on marine predator ecology and conservation, and have direct implications for the management of Gitga’at territory and the identification of fin whale critical habitat in Pacific Canada.

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13

Moran, Catherine. "Consequences of Rainforest Fragmentation for Frugivorous Vertebrates and Seed Dispersal". Thesis, Griffith University, 2007. http://hdl.handle.net/10072/367385.

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Seed dispersal strongly influences patterns of plant regeneration. Frugivorous (fruit eating) vertebrates disperse the seeds of between 70% and 90% of rainforest plant species. Forest fragmentation may affect the abundance and distribution of frugivore species. Consequently, patterns of seed dispersal and plant regeneration may vary between extensive forest and fragmented forest landscapes. This thesis assessed frugivorous vertebrates and seed dispersal in a rainforest landscape in subtropical Australia. First, this study quantitatively compared the distribution and abundance of frugivorous bird and bat species between fragmented and extensive rainforest. Second, the roles of these frugivore species in seed dispersal were evaluated based on their functional attributes and the plant species that they had been recorded consuming. Third, secondary consequences of forest fragmentation for seed dispersal were predicted from these results. The field components of this study were conducted in the Sunshine Coast region of southern Queensland. Surveys of frugivorous bird and bat species were undertaken in a network of 48 study sites distributed throughout a 4 000 km² area. Sites comprised 16 replicates of each of three site types: extensive forest (>4 000 ha), rainforest remnants and patches of secondary regrowth. Extensive forest sites were stratified by altitude (low (<200 m above sea level (a.s.l.), medium (200-500 m a.s.l.), and high (>500 m a.s.l.). Birds were surveyed using 40 minute area searches within a one hectare plot during the early morning. Each site was surveyed for birds four times: twice during summer and twice in winter. Forty-two frugivorous bird species were identified during surveys. Twenty-six of these species occurred frequently enough to quantitatively assess their abundance pattern in remnant and regrowth sites relative to extensive forest. There were five species that were recorded in much lower numbers in remnants and/or regrowth than in extensive forest (‘decreasers’), seven that showed higher abundance in remnants and/or regrowth than in extensive forest (‘increasers’) and 14 whose abundance did not vary substantially between the three habitat types (‘tolerant’ species). The decreasers included four rainforest pigeons (the wompoo, rose-crowned and superb fruit-doves Ptilinopus magnificus, P. regina and P. superbus and brown cuckoo-dove Macropygia amboinensis) and the green catbird Ailuroedus crassirostris. There was no evidence for the complete seasonal movement of frugivorous bird species between high and low altitudes. A lack of understanding of the functional roles of frugivorous species has previously limited our capacity to predict specific consequences for seed dispersal of frugivore declines. A major dimension of functional variation among frugivore species is the suite of plant species that they disperse, which depends initially on their patterns of consumption of plant species. In this thesis, frugivorous bird species that were expected to have similar patterns of plant species consumption were assembled into ‘functional groups’. These groupings were based on the bird species’ gape width, degree of frugivory and their methods of seed treatment. For example, it was proposed that species with wide gapes would be able to consume large fruits, whereas those with narrow gapes could only consume small fruits. It was also expected that species with fruit-dominated diets (‘major frugivores’) may consume a different suite of plant species than species with mixed diets or with diets dominated by non-fruit (‘minor frugivores’). Species that crushed seeds were expected to disperse few viable seeds. Analyses showed that decreaser bird species were predominantly from functional groups that had the potential to disperse large-seeded plant species and may be the main dispersers of native laurels (Lauraceae). Consequently, it is likely that the dispersal of these plants may be reduced in fragmented forest. Relationships between the functional attributes of frugivores and their actual patterns of plant species consumption were analysed using data on the plant species that each frugivore species was known to consume. Diet data were collated from 151 published sources as well as field observation and included records for 244 plant species. Major variation in patterns of plant species consumption corresponded with variation in frugivore species’ attributes. For example, the average size of fruits consumed by bird species increased with their gape width, although minor frugivores tended to consume fruits that were much smaller than their capacity. Statistical comparisons showed that highly frugivorous bird species consumed the highest number of plant species from the Lauraceae, whereas bird species with mixed diets consumed more arillate plant species from the Celastraceae, Sapindaceae, Mimosaceae and Elaeocarpaceae than other frugivore groups. Bird species from a range of functional groups consumed figs and small-fruited plants from families such as Euphorbiaceae and Solanaceae. Minor frugivores and a small number of major and mixed-diet bird species had species-poor diets that were dominated by these latter plant taxa. In order to specifically assess the potential consequences of forest fragmentation for seed dispersal, patterns of plant species consumption were compared among decreaser, tolerant and increaser frugivore species. In particular, the potential for tolerant and increaser bird species to substitute for decreasers was evaluated. Analyses showed that dietary records for 12% of the 220 native plant species represented in the data set, including several from the Rubiaceae, were restricted to decreaser bird species. In addition, analyses showed that few non-decreaser species consumed numbers of native plant species with fruits wider than 10 mm, or from the Lauraceae, Myrtaceae, Meliaceae, Verbenaceae and Vitaceae that were comparable to decreaser bird species. Consequently, it is predicted that there is limited potential for functional substitution by other bird species for decreasers and, therefore, that the dispersal of these plant taxa may be substantially reduced in fragmented compared with extensive rainforest. The potential for frugivorous bats to disperse seeds in fragmented forest was also assessed. Frugivorous bats were surveyed during summer in each of the 48 sites that had been surveyed for birds. Two observers conducted nocturnal, hour long searches along a 400-500 m transect. Two flying-fox species (grey-headed flying-fox Pteropus poliocephalus and black flying-fox P. alecto) and the eastern tube-nosed bat Nyctimene robinsoni were recorded during surveys. At the time of surveys, Pteropus spp. were most frequently recorded in regrowth, whereas N. robinsoni was detected more frequently in extensive forest and remnants than in regrowth. Decreaser bird species and N. robinsoni are rainforest and fruit specialists whereas tolerant and increaser bird species and Pteropus spp. have more generalist patterns of habitat and resource use. N. robinsoni has limited potential to substitute for decreaser bird species as a seed disperser in fragmented rainforest of the study region, because it is known to consume only a small number of plant species and because of its rarity in regrowth. In contrast, Pteropus spp. were widespread in fragmented forest and consumed approximately one-third of the plant species that were consumed by decreaser bird species. In fragmented landscapes, Pteropus spp. may potentially substitute for decreaser bird species as dispersers of large-fruited plant taxa and plants from the Myrtaceae, although they appear unlikely to disperse seeds >9 mm more than short distances away from parent plants. The results of this study show that fragmented remnant and regrowth patches of rainforest do not adequately conserve the full complement of frugivorous vertebrate species in the subtropics of eastern Australia. Although the number of frugivore species that showed sensitivity to rainforest fragmentation was relatively small, this may have substantial functional consequences. These consequences are likely because decreaser species may be the sole or predominant dispersers of a substantial proportion of native plant species, which may consequently be susceptible to reduced dispersal away from parent plants in fragmented forest. Reduced dispersal may have a number of implications for plant regeneration. First, dispersal to recruitment sites within forest fragments is likely to be reduced, resulting in lower rates and clumped spatial patterns of recruitment. Second, dispersal of these species between rainforest fragments may be lower, leading to low rates of recolonisation following local extinctions. Third, short-distance dispersal to new habitats may be lower, resulting in low representation of susceptible plant species in regenerating forest on previously cleared land. Fourth, long distance dispersal of these plant taxa would be low, which would mean that they may have a limited capacity to shift their geographical range, for example in response to changing global climatic conditions. Further clearing and fragmentation of rainforest would exacerbate the situation for decreaser frugivore species and may lead to the decline of additional frugivore species. It is recommended that remaining rainforest be protected from continued clearing. Restoration of forest areas based on the needs of decreaser frugivore species may help to re-establish them in fragmented landscapes. These actions could help to restore the regenerative capacity of many rainforest plant species and hence increase the long term integrity of fragmented rainforest ecosystems.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Faculty of Science, Environment, Engineering and Technology
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14

Hausmann, Franziska. "The Utility of Linear Riparian Rainforest for Vertebrates on the Atherton and Evelyn Tablelands, North Queensland". Thesis, Griffith University, 2004. http://hdl.handle.net/10072/365964.

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This study investigated the utility to vertebrates of upland linear riparian rainforest fragments on the Atherton and Evelyn Tablelands in the Australian Wet Tropics region, north Queensland. Similar linear fragments were selected, that varied in forest age and their connectivity to large areas of continuous forest:- (connected primary (N=6), isolated primary (N=5), connected secondary (N=6) and isolated secondary (N=7)). Primary sites had either never been cleared or only subject to selective logging, while secondary forest had been completely cleared and allowed to regenerate for at least 30 years. These linear fragments were contrasted with riparian sites within continuous forest sites (N=6 to 7), which were situated in State Forest or National Parks, and sites within the cleared matrix (pasture, N=6). Vertebrates surveyed were birds, ground-dwelling mammals and reptiles, particularly leaf-litter skinks. All surveys were conducted between September and December in 2001 and/or 2000. Chapter 2 investigates the effects of forest age, isolation and structural vegetation features on bird assemblages within linear riparian fragments of rainforest. Bird surveys and structural vegetation assessments were conducted within connected and isolated primary and secondary linear fragments, and compared with those of continuous forest habitat (N=6) and pasture. There were strong effects of forest age; all three types of primary rainforest had higher values than secondary rainforest for most measured attributes of vegetation structure (including canopy height and cover; and frequency of large-diameter trees, lianes, epiphytes, strangler figs; and woody debris), but lower frequencies of tree ferns and thorny scramblers. Sites within primary rainforest also had a greater frequency of many bird species across different guilds of habitat, feeding and movement. Assemblages of rainforest-dependent birds showed an effect of isolation, although its strength was less than that of forest age. Isolated fragments of primary rainforest differed significantly from continuous primary rainforest in their rainforest-dependent bird species assemblages (and had lower species richness), and isolated fragments of secondary rainforest differed from those that were connected. There was a significant association between the species composition of rainforest birds and some measured vegetation parameters across all sites, but not within primary or secondary sites. Vegetation differences did not explain the lowered frequency of several species in isolated fragments. Limited dispersal seems unlikely to be a main cause, and causal processes probably vary among species. Specialist rainforest species endemic to the Wet Tropics region showed stronger responses to present-day rainforest age and fragmentation than those not endemic. Variation in nest depredation levels associated with rainforest fragmentation (edge effects) is examined in Chapter 3. Artificial nests were placed in the forest understorey at seven edge sites where continuous forest adjoined pasture, seven interiors (about one kilometre from the edge), and six primary linear riparian forest remnants (50-100 m wide) that were connected to continuous forest. Four nest types were compared, representing different combinations of two factors; height (ground, shrub) and shape (open, domed). At each site, four nests of each type, containing one quail egg and two model plasticine eggs, were interspersed about 15 m apart within a 160 m transect. Predators were identified from marks on the plasticine eggs. The overall depredation rate was 66.5% of 320 nests' contents damaged over a three-day period. Large rodents, especially the rat Uromys caudimaculatus, and birds, especially the spotted catbird Ailuroedus melanotis, were the main predators. Mammals comprised 56.5% and birds 31.0% of identified predators, with 12.5% of unknown identity. The depredation rate did not vary among site-types, or between open and domed nests, and there were no statistically significant interactions. Nest height strongly affected depredation rates by particular types of predator; depredation rates by mammals were highest at ground nests, whereas attacks by birds were most frequent at shrub nests. These effects counterbalanced so that overall there was little net effect of nest height. Mammals accounted for 78.4% of depredated ground nests and birds for at least 47.4% of shrub nests (and possibly up to 70.1%). The main predators were species characteristic of rainforest, rather than habitat generalists, open-country or edge specialists. For birds that nest in the tropical rainforest understorey of the study region, it is unlikely that edges and linear remnants presently function as ecological population sinks due to mortality associated with increased nest depredation. The use of linear riparian remnants by small ground-dwelling mammals and reptiles (mainly leaf litter skinks), is reported in Chapter 4. Site types were continuous rainforest, connected and isolated linear fragments of both uncleared primary rainforest and secondary regrowth rainforest. Mammals were also surveyed in pasture sites. Neither reptile species richness nor abundance varied significantly among site types. Although mammal species richness varied significantly between site types, with isolated primary sites containing highest species richness, overall mammal abundance did not differ significantly among site types. Pasture sites differed significantly from all rainforest sites in their mammal species composition, and were dominated by the introduced house mouse (Mus musculus). This species was absent from all rainforest sites, which were characterised by moderate abundances of bush rat/Cape York rat Rattus fuscipes/leucopus, fawn-footed melomys Melomys cervinipes and giant white-tailed rat Uromys caudimaculatus. None of these species varied significantly in abundance among site types, although the giant white-tailed rat showed a trend (P=0.09) for reduced abundance in isolated secondary sites. A single reptile species, the prickly forest skink Gnypetoscincus queenslandiae, occurred in sufficient numbers for individual analysis, and its abundance varied significantly among the forested site types, being less abundant in all linear fragments than in continuous forest sites. The utility of linear riparian rainforest for vertebrates appears to be species-specific and involves many factors. However, overall, species endemic to the Wet Tropics (which are hence of the highest conservation significance) appear to be the most sensitive to fragmentation. These species were most likely to show altered abundances or frequencies of occurrence due to isolation, forest age, and habitat linearity. The ecology of species within this group warrants further investigation within fragmented and non-fragmented regions of the Tablelands. For many other vertebrates examined in this study, there appears to be sufficient functional connectedness between remnants on the Tablelands to minimise the effects of fragmentation. Nevertheless, the lower density of many of these species in pasture may indicate that their long-term persistence within the fragmented rainforest areas could benefit from the maintenance or establishment of habitat linkages. Certainly, if the current rainforest vegetation cover were further reduced, or if the land use in the matrix became more intensive, the establishment of specific habitat linkages could become more important as existing dispersal routes could be lost. It also appears that nest depredation levels are unlikely to limit the value of linear rainforest remnants and other small rainforest remnants as breeding habitat for birds (at least for understorey-nesting species), relative to more intact rainforest, in the study region
Thesis (Masters)
Master of Philosophy (MPhil)
Australian School of Environmental Studies
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15

Greenwood, David Robert. "The foliar physiognomic analysis and taphonomy of leaf beds derived from modern Australia rainforest". Title page, contents and abstract only, 1987. http://web4.library.adelaide.edu.au/theses/09PH/09phg8165.pdf.

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Palmer, Gary John. "Interactions Between Rainforest Trees and Their Vertebrate Seed Predators in Continuous and Fragmented Habitat". Thesis, Griffith University, 2017. http://hdl.handle.net/10072/366525.

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Ground-active vertebrates can potentially exert a strong influence over the community composition of rainforest trees because they are significant predators of seeds. If the fragmentation of rainforest habitat alters the species composition of vertebrate seed predator assemblages, or patterns of interaction between seed predators and tree species, the subsequent patterns of tree recruitment are also likely to be affected. However, these interactions have not previously been investigated at a community-level. This thesis investigated patterns of community-level interactions between species of ground-active vertebrate seed predators and seeds from a range of common local rainforest tree species in the Big Scrub region of subtropical eastern Australia. In six sites in continuous forest and six sites in fragmented rainforest, ground-active vertebrates were surveyed using automated infra-red videos cameras and predation on seeds of 20 tree species were assessed at experimental seed stations. In addition, laboratory analysis of the physical and chemical traits of the 20 rainforest tree species were conducted.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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17

Cornelius, Cintia. "Genetic and demographic consequences of human-driven landscape changes on bird populations the case of Aphrastura spinicauda (Furnariidae) in the temperate rainforest of South America /". Diss., St. Louis, Mo. : University of Missouri--St. Louis, 2006. http://etd.umsl.edu/r1821.

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Naito, Yoko. "Reproductive ecology and early demography of two dipterocarp species in a lowland tropical rainforest of Peninsular Malaysia". Kyoto University, 2008. http://hdl.handle.net/2433/136600.

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Kyoto University (京都大学)
0048
新制・課程博士
博士(農学)
甲第13873号
農博第1688号
新制||農||953(附属図書館)
学位論文||H20||N4340(農学部図書室)
UT51-2008-C789
京都大学大学院農学研究科森林科学専攻
(主査)教授 太田 誠一, 教授 井鷺 裕司, 教授 大澤 晃
学位規則第4条第1項該当
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19

Marshall, Jonathan Coid, i n/a. "Factors Influencing the Composition of Faunal Assemblages in Rainforest Stream Pools". Griffith University. Australian School of Environmental Studies, 2001. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040218.150407.

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Previous research has shown that a range of physical and biological drivers can influence the composition of faunal assemblages occupying localities within streams. There is much debate in the literature about which of these is more important. Descriptive and experimental field studies were conducted in two relatively undisturbed, second order rainforest streams in southeast Queensland, Australia. The principal objectives were to describe spatial and temporal patterns in pool fauna and explore relationships between these patterns and physical attributes of habitat, disturbance and biotic interactions. The macroinvertebrate and vertebrate fauna of 12 small stream pools were sampled approximately monthly over a period of 15 months. Samples were collected from all major within-pool habitat types and concurrent measurements of potentially important environmental parameters were made at landscape scales of stream, pool and habitat patch. Faunal assemblages were consistently different between the two streams and between the various within-pool habitat types, although the latter may partially be explained by differences in sampling protocols applied in the different habitat types. However, spatial and temporal variation in faunal assemblages within habitat types was large at the scales of whole pools and within-pool habitats, and this variation occurred apparently independently of variation in physical habitat attributes. These results indicated that very little of the local scale faunal variation could be explained by abiotic drivers and that some other factors must be responsible for the observed faunal patterns. Previous research had indicated that atyid shrimps can play a significant ecological role in rainforest streams, where they act as 'ecosystem engineers' by removing fine sediment from hard surfaces. This subsequently alters algal dynamics and faunal composition in streams. A pool-scale manipulative experiment was conducted to investigate the role of the atyid Paratya australiensis, which is an abundant and conspicuous component of the fauna. Removal of shrimp from pools had no effect on sediment accrual on hard surfaces and consequently did not affect algal biomass or faunal assemblages. The lack of effect on sediment accumulation was attributed to the low rate of deposition in these streams, which was an order of magnitude lower than in streams where atyids have been demonstrated to play a keystone role. The fish Mogurnda adspersa was found to be the primary predator of pool fauna in the study streams, where it preyed on a wide variety of taxa. Dietary analyses revealed that an ontogenetic shift occurred in both diet and the within-pool habitat where fish fed. Within this general framework, individual fish had strong individual prey preferences. Significant correlations were found between the natural abundance of Mogurnda in pools and faunal assemblage patterns in both gravel habitat and pools in general, indicating that predation had an effect on pool fauna. The nature of this effect varied between habitats. A direct density dependent response was observed in gravel habitat. In contrast, the response in pools varied considerably between individual pools, perhaps reflecting the differing prey preferences of individual fish. Despite these correlations, an experimental manipulation of the density of Mogurnda at a whole-pool scale did not conclusively identify a predation effect. This may have been due to problems with fish moving between treatments, despite attempts to constrain them, and low experimental power due to the inherent high variability of pool fauna. Overall, the results of the study indicated that there was considerable spatial and temporal variation in pool fauna despite similarities in the physical attributes of pools and their close proximity. This variation appeared to occur at random and could not be explained by abiotic or biotic factors. Predation had a small effect, but could not explain the overall patterns, whereas disturbance by spates had very little effect at all. Stochastic processes associated with low level random recruitment were identified as a possible and plausible explanation for observed patterns. These conclusions are discussed in terms of their implications for our understanding of the ecology and management of streams.
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20

Marshall, Jonathan Coid. "Factors Influencing the Composition of Faunal Assemblages in Rainforest Stream Pools". Thesis, Griffith University, 2003. http://hdl.handle.net/10072/366983.

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Previous research has shown that a range of physical and biological drivers can influence the composition of faunal assemblages occupying localities within streams. There is much debate in the literature about which of these is more important. Descriptive and experimental field studies were conducted in two relatively undisturbed, second order rainforest streams in southeast Queensland, Australia. The principal objectives were to describe spatial and temporal patterns in pool fauna and explore relationships between these patterns and physical attributes of habitat, disturbance and biotic interactions. The macroinvertebrate and vertebrate fauna of 12 small stream pools were sampled approximately monthly over a period of 15 months. Samples were collected from all major within-pool habitat types and concurrent measurements of potentially important environmental parameters were made at landscape scales of stream, pool and habitat patch. Faunal assemblages were consistently different between the two streams and between the various within-pool habitat types, although the latter may partially be explained by differences in sampling protocols applied in the different habitat types. However, spatial and temporal variation in faunal assemblages within habitat types was large at the scales of whole pools and within-pool habitats, and this variation occurred apparently independently of variation in physical habitat attributes. These results indicated that very little of the local scale faunal variation could be explained by abiotic drivers and that some other factors must be responsible for the observed faunal patterns. Previous research had indicated that atyid shrimps can play a significant ecological role in rainforest streams, where they act as 'ecosystem engineers' by removing fine sediment from hard surfaces. This subsequently alters algal dynamics and faunal composition in streams. A pool-scale manipulative experiment was conducted to investigate the role of the atyid Paratya australiensis, which is an abundant and conspicuous component of the fauna. Removal of shrimp from pools had no effect on sediment accrual on hard surfaces and consequently did not affect algal biomass or faunal assemblages. The lack of effect on sediment accumulation was attributed to the low rate of deposition in these streams, which was an order of magnitude lower than in streams where atyids have been demonstrated to play a keystone role. The fish Mogurnda adspersa was found to be the primary predator of pool fauna in the study streams, where it preyed on a wide variety of taxa. Dietary analyses revealed that an ontogenetic shift occurred in both diet and the within-pool habitat where fish fed. Within this general framework, individual fish had strong individual prey preferences. Significant correlations were found between the natural abundance of Mogurnda in pools and faunal assemblage patterns in both gravel habitat and pools in general, indicating that predation had an effect on pool fauna. The nature of this effect varied between habitats. A direct density dependent response was observed in gravel habitat. In contrast, the response in pools varied considerably between individual pools, perhaps reflecting the differing prey preferences of individual fish. Despite these correlations, an experimental manipulation of the density of Mogurnda at a whole-pool scale did not conclusively identify a predation effect. This may have been due to problems with fish moving between treatments, despite attempts to constrain them, and low experimental power due to the inherent high variability of pool fauna. Overall, the results of the study indicated that there was considerable spatial and temporal variation in pool fauna despite similarities in the physical attributes of pools and their close proximity. This variation appeared to occur at random and could not be explained by abiotic or biotic factors. Predation had a small effect, but could not explain the overall patterns, whereas disturbance by spates had very little effect at all. Stochastic processes associated with low level random recruitment were identified as a possible and plausible explanation for observed patterns. These conclusions are discussed in terms of their implications for our understanding of the ecology and management of streams.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Australian School of Environmental Studies
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21

Roberts, Patrick. "Fruits of the forest : human stable isotope ecology and rainforest adaptations in Late Pleistocene and Holocene Sri Lanka". Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:9f314a01-b062-4a9c-9f55-7db943294866.

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Despite ecological, anthropological, and archaeological debate surrounding their desirability as habitats for human occupation, tropical rainforests have received relatively little attention in discussions of Homo sapiens' Pleistocene dispersal. Sri Lanka has yielded some of the earliest dated fossil and material culture evidence (c. 38-35,000 cal. years BP) for our species in a modern rainforest context beyond Africa. Nevertheless, assertions in Sri Lanka, and elsewhere, regarding early human rainforest reliance have been largely based on coarse or 'off-site' palaeoenvironmental records, and the overall role of these environments in human subsistence strategies has remained uncertain. This study applies stable carbon and oxygen isotope analysis to Sri Lankan human fossil, and associated faunal, tooth enamel dated to between 36-29,000 and 3,000 cal. years BP, in order to directly test human rainforest resource reliance, reconstruct a stable isotope ecology, and develop 'on-site' palaeoenvironmental records for Late Pleistocene-Holocene Sri Lankan rainforest foragers. Stable carbon and oxygen isotope analysis of modern Sri Lankan primates, and stable carbon, oxygen, and nitrogen isotope analysis of modern plant samples from the Polonnaruwa Nature Sanctuary, are also performed to investigate the ecology of Sri Lankan primates on which Late Pleistocene-Holocene forager subsistence strategies were focused. The results demonstrate that Homo sapiens relied on rainforest resources in Sri Lanka from c. 36-29,000 cal. years BP until the Iron Age c. 3 cal. years BP, even when open environments, and their corresponding resources, were available. This remains the case through periods of evident environmental change at the Last Glacial Maximum and even upon the arrival of agriculture in the island's tropical forests. The primate stable isotope data prove difficult to interpret as ecological niche separation in the absence of observation data. Nonetheless, humans were evidently able to not only use but also rapidly specialise in the exploitation of South Asia's rainforests.
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22

Woebbe, Eric. "Survey of a Neotropical anuran assemblage (Pacaya-Samiria Reserve, Peru)". Wright State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=wright1493154522047725.

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23

Maunsell, Sarah. "Food Webs along Elevational Gradients: Interactions among Leaf Miners, Host Plants and Parasitoids in Australian Subtropical Rainforest". Thesis, Griffith University, 2014. http://hdl.handle.net/10072/368145.

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Gradients in elevation are used to understand how species respond to changes in local climatic conditions and are therefore a powerful tool for predicting how mountain ecosystems may respond to climate change. While many studies have shown elevational patterns in species richness and species turnover, little is known about how multi-species interactions respond to elevation. An understanding of how species interactions are affected by current clines in climate is imperative if we are to make predictions about how ecosystem function and stability will be affected by climate change. This challenge has been addressed here by focussing on a set of intimately interacting species: leaf-mining insects, their host plants and their parasitoid predators. Herbivorous insects, including leaf miners, and their host plants and parasitoids interact in diverse and complex ways, but relatively little is known about how the nature and strengths of these interactions change along climatic gradients. In order to determine how elevational changes in climatic conditions affect interactions among leaf miners, their host plants and their parasitoids, I quantified these communities and their interactions along three elevational gradients in eastern Australian subtropical rainforest. In doing so, I aimed to 1) provide information on host plant use of leaf miners and the elevational associations of these relationships, 2) understand how the species richness and assemblage composition leaf miners and their parasitoids, and composition of interactions with their hosts (plants or leaf miners), is affected by elevation, 3) uncover any elevational changes in the structure of quantitative networks connecting leaf miners and their parasitoids, and 4) test if parasitism pressure increases at the lower edge of, and below the elevational range of a specific leaf miner species.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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24

Hausmann, Franziska, i n/a. "The Utility of Linear Riparian Rainforest for Vertebrates on the Atherton and Evelyn Tablelands, North Queensland". Griffith University. Australian School of Environmental Studies, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20050115.105740.

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This study investigated the utility to vertebrates of upland linear riparian rainforest fragments on the Atherton and Evelyn Tablelands in the Australian Wet Tropics region, north Queensland. Similar linear fragments were selected, that varied in forest age and their connectivity to large areas of continuous forest:- (connected primary (N=6), isolated primary (N=5), connected secondary (N=6) and isolated secondary (N=7)). Primary sites had either never been cleared or only subject to selective logging, while secondary forest had been completely cleared and allowed to regenerate for at least 30 years. These linear fragments were contrasted with riparian sites within continuous forest sites (N=6 to 7), which were situated in State Forest or National Parks, and sites within the cleared matrix (pasture, N=6). Vertebrates surveyed were birds, ground-dwelling mammals and reptiles, particularly leaf-litter skinks. All surveys were conducted between September and December in 2001 and/or 2000. Chapter 2 investigates the effects of forest age, isolation and structural vegetation features on bird assemblages within linear riparian fragments of rainforest. Bird surveys and structural vegetation assessments were conducted within connected and isolated primary and secondary linear fragments, and compared with those of continuous forest habitat (N=6) and pasture. There were strong effects of forest age; all three types of primary rainforest had higher values than secondary rainforest for most measured attributes of vegetation structure (including canopy height and cover; and frequency of large-diameter trees, lianes, epiphytes, strangler figs; and woody debris), but lower frequencies of tree ferns and thorny scramblers. Sites within primary rainforest also had a greater frequency of many bird species across different guilds of habitat, feeding and movement. Assemblages of rainforest-dependent birds showed an effect of isolation, although its strength was less than that of forest age. Isolated fragments of primary rainforest differed significantly from continuous primary rainforest in their rainforest-dependent bird species assemblages (and had lower species richness), and isolated fragments of secondary rainforest differed from those that were connected. There was a significant association between the species composition of rainforest birds and some measured vegetation parameters across all sites, but not within primary or secondary sites. Vegetation differences did not explain the lowered frequency of several species in isolated fragments. Limited dispersal seems unlikely to be a main cause, and causal processes probably vary among species. Specialist rainforest species endemic to the Wet Tropics region showed stronger responses to present-day rainforest age and fragmentation than those not endemic. Variation in nest depredation levels associated with rainforest fragmentation (edge effects) is examined in Chapter 3. Artificial nests were placed in the forest understorey at seven edge sites where continuous forest adjoined pasture, seven interiors (about one kilometre from the edge), and six primary linear riparian forest remnants (50-100 m wide) that were connected to continuous forest. Four nest types were compared, representing different combinations of two factors; height (ground, shrub) and shape (open, domed). At each site, four nests of each type, containing one quail egg and two model plasticine eggs, were interspersed about 15 m apart within a 160 m transect. Predators were identified from marks on the plasticine eggs. The overall depredation rate was 66.5% of 320 nests' contents damaged over a three-day period. Large rodents, especially the rat Uromys caudimaculatus, and birds, especially the spotted catbird Ailuroedus melanotis, were the main predators. Mammals comprised 56.5% and birds 31.0% of identified predators, with 12.5% of unknown identity. The depredation rate did not vary among site-types, or between open and domed nests, and there were no statistically significant interactions. Nest height strongly affected depredation rates by particular types of predator; depredation rates by mammals were highest at ground nests, whereas attacks by birds were most frequent at shrub nests. These effects counterbalanced so that overall there was little net effect of nest height. Mammals accounted for 78.4% of depredated ground nests and birds for at least 47.4% of shrub nests (and possibly up to 70.1%). The main predators were species characteristic of rainforest, rather than habitat generalists, open-country or edge specialists. For birds that nest in the tropical rainforest understorey of the study region, it is unlikely that edges and linear remnants presently function as ecological population sinks due to mortality associated with increased nest depredation. The use of linear riparian remnants by small ground-dwelling mammals and reptiles (mainly leaf litter skinks), is reported in Chapter 4. Site types were continuous rainforest, connected and isolated linear fragments of both uncleared primary rainforest and secondary regrowth rainforest. Mammals were also surveyed in pasture sites. Neither reptile species richness nor abundance varied significantly among site types. Although mammal species richness varied significantly between site types, with isolated primary sites containing highest species richness, overall mammal abundance did not differ significantly among site types. Pasture sites differed significantly from all rainforest sites in their mammal species composition, and were dominated by the introduced house mouse (Mus musculus). This species was absent from all rainforest sites, which were characterised by moderate abundances of bush rat/Cape York rat Rattus fuscipes/leucopus, fawn-footed melomys Melomys cervinipes and giant white-tailed rat Uromys caudimaculatus. None of these species varied significantly in abundance among site types, although the giant white-tailed rat showed a trend (P=0.09) for reduced abundance in isolated secondary sites. A single reptile species, the prickly forest skink Gnypetoscincus queenslandiae, occurred in sufficient numbers for individual analysis, and its abundance varied significantly among the forested site types, being less abundant in all linear fragments than in continuous forest sites. The utility of linear riparian rainforest for vertebrates appears to be species-specific and involves many factors. However, overall, species endemic to the Wet Tropics (which are hence of the highest conservation significance) appear to be the most sensitive to fragmentation. These species were most likely to show altered abundances or frequencies of occurrence due to isolation, forest age, and habitat linearity. The ecology of species within this group warrants further investigation within fragmented and non-fragmented regions of the Tablelands. For many other vertebrates examined in this study, there appears to be sufficient functional connectedness between remnants on the Tablelands to minimise the effects of fragmentation. Nevertheless, the lower density of many of these species in pasture may indicate that their long-term persistence within the fragmented rainforest areas could benefit from the maintenance or establishment of habitat linkages. Certainly, if the current rainforest vegetation cover were further reduced, or if the land use in the matrix became more intensive, the establishment of specific habitat linkages could become more important as existing dispersal routes could be lost. It also appears that nest depredation levels are unlikely to limit the value of linear rainforest remnants and other small rainforest remnants as breeding habitat for birds (at least for understorey-nesting species), relative to more intact rainforest, in the study region.
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Coelho, Luís Francisco Mello. "Ecologia de hemiepífitas estranguladoras no Parque Estadual da Ilha do Cardoso /". Rio Claro : [s.n.], 2005. http://hdl.handle.net/11449/87846.

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Orientador: Marco Aurélio Pizo
Banca: Leila Cunha de Moura
Banca: Fernando Roberto Martins
Resumo: Hemiepífitas estranguladoras são plantas que crescem sobre árvores (hospedeiros) e posteriormente enviam raízes para conexão com o solo. Depois de alcançar o estoque de água e nutrientes do solo se desenvolvem até atingir um grande porte e se tornarem capazes de se auto sustentar. Durante seu desenvolvimento competem com os hospedeiros por oportunidades de expansão da copa e por água e nutrientes do solo, além de afetarem negativamente a translocação de água e nutrientes pelo sistema vascular de seu hospedeiro devido à constrição provocada no fuste e galhos do hospedeiro pelo sistema de raízes estrangulantes típico dessas plantas. Apesar de serem componentes importantes de florestas tropicais, estudos sobre a estrutura populacional de hemiepífitas estranguladoras são raros, aspecto este que norteou os objetivos do presente trabalho, que tem como proposta levantar a riqueza e densidade das hemiepífitas estranguladoras, analisar e comparar a estrutura populacional e as formas de utilização do dossel florestal entre os gêneros estudados. O estudo foi conduzido nas áreas de Floresta Tropical Pluvial da Serra do Mar e de Floresta Tropical Pluvial de Planície Litorânea, ambas situadas no Parque Estadual da Ilha do Cardoso (PEIC), no extremo sul do litoral paulista. Os dois gêneros amostrados causam dano letal ao hospedeiro e não diferem quanto ao tipo ou freqüência do impacto sobre os hospedeiros, apesar dos diferentes padrões morfológicos do sistema de raízes estrangulantes de cada gênero. As hemiepífitas estranguladoras ocorrem em alta densidade na Ilha do Cardoso e, pelos aspectos de sua ecologia aqui investigados, exercem importante papel na estrutura e regeneração do dossel florestal
Abstract: Strangling hemiepiphytes are plants that grow in trees (hosts) and later send their roots to connect with the soil. After reaching the water supply and nutrients in the soil, they evolve to a considerable size and are capable of self-support. Throughout their development they compete with their hosts for opportunities to expand their crowns and to get water and soil nutrients, besides negatively affecting water and nutrients translocation through the vascular system of their host by constricting the host trunk and branch using the root-constrictor system typical of such plants. Therefore, they can cause premature death of their hosts. Despite being important elements in tropical forests, studies of the population structure of strangling hemiepiphytes are rare. This study aims at investigating the richness and density of these strangling hemiepiphytes to further compare population structure of two genera and the ways each uses the forest canopy. The study was conducted in the Plain Tropical Forest and in the Slope Tropical Forest areas within the Cardoso Island State Park (PEIC), situated in the extreme south of the coast of the state of São Paulo, southeast Brazil. Both sampled genera cause lethal damage to the host and do not differ in terms of type or frequency of impact over the hosts, despite the different morphological patterns in the strangling roots systems of each genus. The strangling hemiepiphytes occur in a high density on Cardoso island, and, because of their distinctive biological aspects discussed above, play an important role in the structuring and regeneration of forest canopy
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26

Jessen, Rosa Raquel. "Behavior and Ecology of Neotropical Tree Squirrels in Seasonally Flooded Forests in the Peruvian Amazon". Thesis, The University of Arizona, 2013. http://hdl.handle.net/10150/293536.

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Tree squirrels play an important role in the maintenance of forest ecosystems by functioning as seed and fungal spore dispersers, forest regenerators, and prey for forest predators. The highest species richness for tree squirrels occurs in tropical forests and these species are also the least studied. We conducted distance sampling to estimate population density, measured habitat variables to investigate forest characteristics that influence habitat selection and feeding site selection at three different scales, and conducted observations to obtain knowledge about activity pattern and behavior of Neotropical pygmy squirrels and Amazon red squirrels in the Peruvian Amazon. Density of Neotropical pygmy squirrels was 0.10 and 0.14 individuals/ha for 2009 and 2010. Activity peaked in early morning, squirrels were found mainly in the canopy but never on the ground, and frequency of behaviors differed by time and story level. Neotropical pygmy squirrels used mainly high and low restinga and areas that had more large trees. Squirrels also used species of trees disproportionately to availability. Neotropical pygmy squirrels seem to be associated with features related to mature forests. Amazon red squirrels use mainly high and low restinga and selected Astrocaryum and Attalea palm trees that were taller and larger as foraging sites compared to random locations. Amazon red squirrels used all vertical strata of the forest and the main behaviors observed were travel and forage. Behaviors were similar among time periods but differed in frequency by vertical strata. Although Amazon red squirrels used vegetation communities differently than their availability and selected for tree characteristics, they did not select for site characteristics and this is different from other tree squirrel species. We also conducted surveys during a wet and a dry year to investigate and estimate diversity of diurnal mammals. We assessed the vertical strata of the forest to determine if diversity index varied by story level, and estimated alpha, beta, and gamma diversity. Overall mammal diversity did not differ between wet and dry years. Diversity index differed by story level between years, but was the highest in the canopy for both years. Alpha diversity was higher in the dry year, and gamma and beta diversity were higher in the wet year. Frequency of sightings of species was influenced by time of day and varied by story level. Protection of continuous, mature forests with large canopies has important conservation implications as these areas most likely protect the greatest diversity of mammals while also providing shelter and food for other taxa.
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27

Mota, Mateus Ribeiro. "Filogeografia do complexo pitcairnia flammea (Bromeliaceae) /". Rio Claro, 2019. http://hdl.handle.net/11449/190854.

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Orientador: Clarisse Palma da Silva
Resumo: A filogeografia surgiu como uma ponte entre várias disciplinas evolutivas, como a genética populacional, filogenia e biogeografia, estabelecendo ligações entre os estudos micro e macro evolutivos. A filogeografia tem sido cada vez mais utilizada para estudar a evolução de regiões com altos índices de diversidade, como a região Neotrópical. Os Neotrópicos apresentam uma grande variedade de biomas, incluindo a Floresta Atlântica, a segunda maior floresta tropical da América do Sul, contendo mais de 60% de todas as espécies terrestres do planeta. Um número crescente de estudos filogeográficos com espécies da Floresta Atlântica nos ajudado a entender os processos evolutivos que gradualmente formaram essa grande biodiversidade. Realizamos análises filogeográficas, avaliando padrões de estrutura e diversidade genética, tempo de divergência das linhagens e a demografia histórica do complexo de espécies Pitcairnia flammea (Bromeliaceae), grupo adaptado a inselbergs neotropicais naturalmente fragmentados, baseados em conjuntos de dados de microssatélites nucleares e sequências plastidiais. Nossos resultados mostraram baixa a moderada diversidade genética nuclear dentro de populações de P. flammea, e alta estrutura genética populacional, com poucos haplótipos de DNA plastidial compartilhados entre populações, indicando fluxo gênico limitado e baixa conectividade entre afloramentos rochosos. Não encontramos nenhuma estrutura filogeográfica clara, além de duas linhagens evolutivas que di... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Phylogeography has emerged as a bridge between several evolutionary disciplines, such as population genetics, phylogeny and biogeography, establishing the link between micro and macroevolutionary studies. Phylogeography has been increasingly used to study the evolution of regions with high diversity indexes, such as the Neotropic region. The Neotropics presents a wide variety of biomes, including the Atlantic Rainforest, the second largest tropical rainforest in South America containing more than 60% of all terrestrial species on the planet. An increasing number of phylogeographic studies in Atlantic Rainforest species have helped us to understand the evolutionary process that gradually formed such great biodiversity. We performed phylogeographic analyses, assessing genetic structure patterns, timing of lineage divergence and historical demography of Pitcairnia flammea species complex (Bromeliaceae), which are adapted to naturally fragmented Neotropical inselbergs, based on nuclear microsatellites and plastid sequence data sets. Our results showed low to moderate nuclear genetic diversity within P. flammea populations, and high population genetic structure, with few plastid DNA haplotype shared among populations, indicating limited gene flow and low connectivity among rock outcrops. We found no clear phylogeographic structure, besides two evolutionary lineage which diverged approximately 2 Mya., suggesting an important role of early Pleistocene climatic changes in the diversi... (Complete abstract click electronic access below)
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28

Nightingale, Joanne M. "Modelling carbon dynamics within tropical rainforest environments using the 3-PG and 3-PGS ecosystem process models /". [St. Lucia, Qld.], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18498.pdf.

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29

Rahman, Dede Aulia. "New insights into ecology and conservation status of Bawean deer (Axis kuhlii) and red muntjac (Muntiacus muntjak) in Indonesian tropical rainforest". Thesis, Toulouse 3, 2016. http://www.theses.fr/2016TOU30136.

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Les objectifs de cette étude consistaient d'une part à étudier l'écologie de deux cerf tropical de taille moyenne, le cerf de Bawean Axis kuhlii et le Muntjac Muntiacus muntjac dans la réserve naturelle et sanctuaire de la vie sauvage de l'île de Bawean et le parc national d'Ujung Kulon respectivement, et d'autre part de mettre à jour leur statut de conservation. Nous avons utilisé pour la première fois une nouvelle technique de contrôle, les caméras-pièges, associées à aux méthodes écologiques classiques afin d'évaluer la taille des populations, d'examiner l'utilisation de l'habitat, d'estimer le domaine utilisé et d'identifier les patrons d'activité. Les résultats montrent que si les caméra-pièges sont couteuses au départ, elles ont facilité le recueil de données sur le terrain et ont fourni beaucoup d'informations pour les analyses ultérieures. De plus, la méthode des caméra-pièges a permis d'acquérir un plus grand nombre d'informations sur espèces étudiées mais aussi sur les autres espèces présentes sur les sites, que les autres méthodes employées. Pour l'estimation des tailles de population nous avons utilisé un modèle de rencontre aléatoire (REM), une technique efficace pour évaluer la densité d'espèce élusives, rares et dont les individus ne sont pas reconnaissables individuellement. Ce qui ne peut être obtenu par la technique de capture-recapture photographique qui requière que les individus soient identifiables et donc une grande qualité photographique. Les résultats ont été comparés avec ceux obtenus par la technique de comptage de tas de fèces. Les deux méthodes ont fourni des évaluations de densité de population semblables, plus élevées durant la saison sèche et une taille de population estimée entre 227 et 416 cerfs de Bawean. L'étendue de l'aire utilisée par le cerf de Bawean est apparue considérablement plus réduite que lors des précédentes estimations, le comptage de tas de fèces ayant fourni des données complémentaires aux images issues des caméra-pièges. Les deus espèces de cervidés ont essentiellement été relevées dans des habitats de forêt secondaire. L'analyse faite par la méthode de l'entropie maximale (Maxent) a montré que les variables anthropogéniques (pour les deux espèces) et climatiques (Muntjac seulement) sont les prédicteurs principaux pour l'utilisation de l'habitat. Enfin, en utilisant les indicateurs horaires fournis par les caméra-pièges, les patrons d'activité ont été examinés en relation avec le sexe et les conditions environnementales. Bien qu'il soit considéré comme espèce nocturne, l'essentiel des clichés de cerf de Bawean ont été pris durant le jour, et l'activité nocturne dépend de la luminosité. Le muntjac a également témoigné d'une certaine activité diurne avec les plus forts pics situés après le lever et avant le coucher de soleil, alors que l'activité nocturne n'est pas apparue liée à la luminosité. Il n'a pas été observé de différences entre mâles et femelles pour les deux espèces. Alors que le statut du muntjac est classé "peu préoccupant" par UICN, même si des mesures locales de conservation devraient être prises dans la zone d'étude, le cerf de Bawean devrait être maintenu dans la catégorie "en danger critique" car cette population qui apparaît toujours aussi réduite est toujours soumise à une perte d'habitat par déforestation illégale et à des perturbations par les chiens et les chasseurs
The aim of this study was to investigate the ecology of two medium-sized tropical deer, the Bawean deer Axis kuhlii and the red muntjac Muntiacus muntjac in Bawean Island Nature Reserve and Wildlife Sanctuary and Ujung Kulon National Park respectively, and to update their conservation status. We used for the first time a new monitoring technique, camera trapping, together with classical ecological field methods for estimating population size, investigating habitat use, predicting range, and identifying activity pattern. Results show that camera traps were initially expensive but they lightened the field work and provided much information for further analyses. Moreover, camera trapping provided a higher number of records and accurate species identification than other methods. For estimating population size we used a random encounter model (REM), a technique accurate for estimating density of elusive, rare and unmarked species contrary to photographic capture-recapture techniques which require both unique mark and good photographs for individual recognition, and compared the results with those obtained by faecal pellet group count. Both methods provided similar population density estimates, higher in the dry than in the wet season, and a population size of ca. 227-416 deer. The range of Bawean deer established dramatically narrower than previously reported, faecal pellet group count bringing additional data to camera trapping. Both deer species were mainly recorded in secondary forests; Analysis with Maximum entropy model (Maxent) showed that anthropogenic (for both species) and climatic (for red muntjac only) variables were the main predictors of habitat use. Finally, using time data recorded by camera traps, we investigated the activity pattern related to sex and environmental conditions. The believed nocturnal Bawean deer was predominantly photographed during the day, and its nocturnal activity was linked to luminosity. Red muntjac also showed some diurnal activity with higher peaks after sunrise and before sunset, and a nocturnal activity which was not influenced by luminosity. No difference was observed between males and females for both species. Whereas red muntjac is listed "Least concern" by IUCN even if local conservation measures should be undertaken in our study area, Bawean deer should remain "Critically endangered" as the population is still small and the main threats, habitat loss due to illegal logging and human disturbance by dogs and hunters, are ongoing
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30

Sjödin, Henrik. "Effects of commercial use of tropical rainforest on communities of riparian frogs on Borneo: an identification of relevant environmental and microclimatic factors". Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-30917.

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31

Edenborg, Fanny. "Differences in forest structure in relation to energy-efficient cookstoves in the Kakamega forest, Kenya". Thesis, Linköpings universitet, Biologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-167491.

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Tropical forests are amongst the most important ecosystems in the world. It is also the biome estimated to experience the most rapid losses of habitats in the next 50 years, mainly due to anthropogenic exploitation. The Kakamega forest, western Kenya, is important both for conservation and human livelihood and is essential for peoples’ survival. The main threat to the forest’s subsistence is collection of firewood used for cooking. Energy-efficient cookstoves, with almost 50 % lower demand for firewood compared to traditional 3-stone-stoves, have been installed to ease the pressure on the forest. The present study evaluates the effect of utilizing energy-efficient cookstoves, installed during the project Stoves for Life (years 2010-2019), on the forest structure of the Kakamega forest, Kenya. This was done by quantifying forest structural and compositional differences, as well as occurrence of human made damage, within the Kakamega forest. Sampling was made in 59 plot locations, with varying numbers of energy-efficient cookstoves in the surrounding area. Results indicate that the stoves 1) promote recruitment of both pioneer and climax trees and 2) increase survival of fast-growing pioneer trees, 3) ease the pressure on preferred species used as firewood and 4) preserve important structural components such as woody debris found on the forest floor. Additionally, the growth of pioneer trees is potentially creating a climate suitable for later successional species to thrive and establish, potentially leading to forest maturation. However, future comparative studies should be conducted before any statement about the stoves’ effect on forest structure is made.
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32

Coelho, Luís Francisco Mello [UNESP]. "Ecologia de hemiepífitas estranguladoras no Parque Estadual da Ilha do Cardoso". Universidade Estadual Paulista (UNESP), 2005. http://hdl.handle.net/11449/87846.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Hemiepífitas estranguladoras são plantas que crescem sobre árvores (hospedeiros) e posteriormente enviam raízes para conexão com o solo. Depois de alcançar o estoque de água e nutrientes do solo se desenvolvem até atingir um grande porte e se tornarem capazes de se auto sustentar. Durante seu desenvolvimento competem com os hospedeiros por oportunidades de expansão da copa e por água e nutrientes do solo, além de afetarem negativamente a translocação de água e nutrientes pelo sistema vascular de seu hospedeiro devido à constrição provocada no fuste e galhos do hospedeiro pelo sistema de raízes estrangulantes típico dessas plantas. Apesar de serem componentes importantes de florestas tropicais, estudos sobre a estrutura populacional de hemiepífitas estranguladoras são raros, aspecto este que norteou os objetivos do presente trabalho, que tem como proposta levantar a riqueza e densidade das hemiepífitas estranguladoras, analisar e comparar a estrutura populacional e as formas de utilização do dossel florestal entre os gêneros estudados. O estudo foi conduzido nas áreas de Floresta Tropical Pluvial da Serra do Mar e de Floresta Tropical Pluvial de Planície Litorânea, ambas situadas no Parque Estadual da Ilha do Cardoso (PEIC), no extremo sul do litoral paulista. Os dois gêneros amostrados causam dano letal ao hospedeiro e não diferem quanto ao tipo ou freqüência do impacto sobre os hospedeiros, apesar dos diferentes padrões morfológicos do sistema de raízes estrangulantes de cada gênero. As hemiepífitas estranguladoras ocorrem em alta densidade na Ilha do Cardoso e, pelos aspectos de sua ecologia aqui investigados, exercem importante papel na estrutura e regeneração do dossel florestal.
Strangling hemiepiphytes are plants that grow in trees (hosts) and later send their roots to connect with the soil. After reaching the water supply and nutrients in the soil, they evolve to a considerable size and are capable of self-support. Throughout their development they compete with their hosts for opportunities to expand their crowns and to get water and soil nutrients, besides negatively affecting water and nutrients translocation through the vascular system of their host by constricting the host trunk and branch using the root-constrictor system typical of such plants. Therefore, they can cause premature death of their hosts. Despite being important elements in tropical forests, studies of the population structure of strangling hemiepiphytes are rare. This study aims at investigating the richness and density of these strangling hemiepiphytes to further compare population structure of two genera and the ways each uses the forest canopy. The study was conducted in the Plain Tropical Forest and in the Slope Tropical Forest areas within the Cardoso Island State Park (PEIC), situated in the extreme south of the coast of the state of São Paulo, southeast Brazil. Both sampled genera cause lethal damage to the host and do not differ in terms of type or frequency of impact over the hosts, despite the different morphological patterns in the strangling roots systems of each genus. The strangling hemiepiphytes occur in a high density on Cardoso island, and, because of their distinctive biological aspects discussed above, play an important role in the structuring and regeneration of forest canopy.
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33

Brown, Calum. "Spatial patterns and species coexistence : using spatial statistics to identify underlying ecological processes in plant communities". Thesis, University of St Andrews, 2012. http://hdl.handle.net/10023/3084.

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The use of spatial statistics to investigate ecological processes in plant communities is becoming increasingly widespread. In diverse communities such as tropical rainforests, analysis of spatial structure may help to unravel the various processes that act and interact to maintain high levels of diversity. In particular, a number of contrasting mechanisms have been suggested to explain species coexistence, and these differ greatly in their practical implications for the ecology and conservation of tropical forests. Traditional first-order measures of community structure have proved unable to distinguish these mechanisms in practice, but statistics that describe spatial structure may be able to do so. This is of great interest and relevance as spatially explicit data become available for a range of ecological communities and analysis methods for these data become more accessible. This thesis investigates the potential for inference about underlying ecological processes in plant communities using spatial statistics. Current methodologies for spatial analysis are reviewed and extended, and are used to characterise the spatial signals of the principal theorised mechanisms of coexistence. The sensitivity of a range of spatial statistics to these signals is assessed, and the strength of such signals in natural communities is investigated. The spatial signals of the processes considered here are found to be strong and robust to modelled stochastic variation. Several new and existing spatial statistics are found to be sensitive to these signals, and offer great promise for inference about underlying processes from empirical data. The relative strengths of particular processes are found to vary between natural communities, with any one theory being insufficient to explain observed patterns. This thesis extends both understanding of species coexistence in diverse plant communities and the methodology for assessing underlying process in particular cases. It demonstrates that the potential of spatial statistics in ecology is great and largely unexplored.
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34

Fischer, Georg [Verfasser]. "Ecology, biogeography and responses to habitat degradation of a highly diverse rainforest ant community and taxonomy of Afrotropical Pheidole Westwood (Hymenoptera, Formicidae) / Georg Fischer". Bonn : Universitäts- und Landesbibliothek Bonn, 2012. http://d-nb.info/1044846739/34.

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Bourguignon, Thomas. "The Anoplotermes group in French Guiana :systematics, diversity and ecology". Doctoral thesis, Universite Libre de Bruxelles, 2010. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210132.

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Les termites forment un groupe animal important en milieu tropical, où leur richesse spécifique est plus élevée que dans n’importe quel autre écosystème. Ils se nourrissent de matière organique végétale à différent état de décomposition, du bois dur à la matière organique minérale du le sol. Cette diversification du régime alimentaire ne se produit que chez les Termitidae, parfois appelés « termites supérieurs », alors que les autres familles se nourrissent exclusivement de bois ou d’herbe. Les termites humivores sont extrêmement abondants en Amérique du Sud et en Afrique tropicale, mais sont relativement peu étudiés par rapport aux termites xylophages. C’est particulièrement vrai pour le groupe Anoplotermes, qui représente le groupe de termites le moins bien connu. Ce travail vise à faire la lumière sur l’écologie et la diversité de ce groupe strictement humivore, et comprend les sections suivantes :(1) Des échantillonnages standardisés dans sept sites de Guyane Française ont révèle, avec quelques exceptions, que les termites xylophages sont relativement peu spécialisés à un site. Au contraire, les espèces du groupe Anoplotermes, ainsi que les termites humivores en général, sont spécialisés à un type de forêt. Cette spécialisation contribue plus que probablement à la diversification écologique, et donc, à une augmentation de la richesse spécifique des termites humivores. (2) En utilisant les ratios d’isotopiques δ13C et δ15N, nous avons aussi trouvé qu’il existe une spécialisation des espèces le long d’un gradient d’humification chez le groupe Anoplotermes, de l’interface entre le bois pourri et le sol au sol pauvre en matière organique. Donc, au moins deux facteurs favorisent la richesse spécifique du groupe Anoplotermes dans le sol, malgré le manque d’évidence pour une séparation spatiale et temporelle entre les espèces. Cette spécialisation spécifique réduit la compétition interspécifique aux espèces se nourrissant de matière organique au même état de décomposition. (3) Ce mécanisme n’est probablement pas restreint aux espèces du groupe Anoplotermes et le ratio isotopique δ15N varie considérablement entre les termites humivores de manière générale. Les termites humivores comptent des espèces avec des régimes alimentaires différents ne partageant pas toujours les mêmes niches écologiques. Cette diversification du régime alimentaire ne c’est pas produit de manière aléatoire durant l’évolution des termites et les espèces proches tendent à se nourrir du même substrat. (4) Au niveau intraspécifique, il semble que la compétition contraigne la dynamique des colonies. En effet, chez A. banksi, nous avons trouvé que les nids matures sont surdispersés. Les nouveaux nids se trouvent principalement à une certaine distance des nids établis, plus particulièrement dans les trous laissés par les nids morts. Si ce patron est le résultat d’une sélection des sites de nidification, ou plutôt d’une exclusion compétitive reste sujet à discussion, mais met néanmoins en évidence la présence de compétition chez les termites humivores du groupe Anoplotermes. (5) Au vu de la richesse spécifique locale du groupe Anoplotermes, le nombre d’espèces décrites reste remarquablement bas. Après inspection du matériel type, seuls 30 espèces du groupe se sont avérés valides en Amérique du Sud, alors que 80% des espèces que nous avons collectées sont nouvelles pour la science. Cette disproportion entre ce qui est connu et la diversité réelle du groupe, met en évidence le besoin de réaliser des études supplémentaires pour améliorer la connaissance de ce groupe peu connu, le groupe Anoplotermes.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished
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36

VALLE, Ivana Cola. "An?lise dos m?ltiplos usos e das estrat?gias de conserva??o na Bacia do Rio Aldeia Velha, RJ". Universidade Federal Rural do Rio de Janeiro, 2011. https://tede.ufrrj.br/jspui/handle/jspui/1282.

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CAPES
The landscape should be interpreted with the objective of identify which areas are most suitable for the development of the various socioeconomic activities and as areas of environmental protection in order to contribute to sustainable development. This work aims to conduct an integrated analysis of the structural features of the landscape in an area in Rio de Janeiro State?s Coastal Atlantic Forest, evaluating the influence of different forms of land use and occupancy of lands on the conservation of biodiversity and maintenance of environmental balance in the basin of Aldeia Velha river. Through a systemic approach, was analyzed the interactive units of the landscape by instruments used in environmental monitoring programs to evaluate the effectiveness of strategies for maintenance of biodiversity in an area of great ecological relevance, covering part of the territory of Brazil?s first Biological Reserve, Biological Reserve Po?o das Antas, home of endemic and endangered species extinction, due maintly to the reduction of its habitat in lownlands areas. Was quantified the effects of negative and positive impacts in the region, regarding the effects of human activities related to the creation of Reserves and Environmental Protection Areas. Methods used were effective and the results indicated the effectiveness of the area occupied by the Biological Reserve for an increase in forest cover and for the maintenance of benthic biodiversity, as well as the priority sites for restoration and conservation of forest cover to ensure the environmental quality. Thus, it is intended to strengthen appropriate management conditions to subsidize projects that take into account the processes of occupation and nature conservation, environmental fragility and the consequences of degradation of the Atlantic Forest in the biodiversity and quality of life in the study watershed.
A paisagem deve ser interpretada com o objetivo de identificar os espa?os mais adequados para o desenvolvimento das diversas atividades socioecon?micas e as ?reas destinadas ? prote??o, de modo a contribuir com o desenvolvimento sustent?vel. Este trabalho tem como objetivo realizar uma an?lise integrada das caracter?sticas estruturais da paisagem em uma regi?o de Mata Atl?ntica litor?nea fluminense, avaliando a influ?ncia das diferentes formas de uso/ocupa??o do solo sobre a conserva??o da biodiversidade e a manuten??o do equil?brio ambiental na bacia do rio Aldeia Velha (RJ). Atrav?s de uma abordagem sist?mica, analisou-se as unidades interativas da paisagem atrav?s de instrumentos utilizados em programas de monitoramento ambiental na avalia??o da efetividade das estrat?gias para a manuten??o da biodiversidade em uma ?rea de grande relev?ncia ecol?gica, que abrange parte do territ?rio da primeira Reserva Biol?gica do Brasil, a REBIO Po?o das Antas, abrigo de esp?cies end?micas e amea?adas de extin??o em decorr?ncia principalmente da diminui??o de seu habitat em ?reas de baixada. Foram quantificados os efeitos dos impactos negativos e positivos na ?rea de estudo, em fun??o das atividades humanas e relacionados ? cria??o de Reservas e ?reas e de prote??o ambiental. Os m?todos utilizados mostraram-se eficientes e os resultados indicaram uma relevante contribui??o da Reserva Biol?gica para um incremento na cobertura florestal e para a manuten??o da biodiversidade bent?nica na por??o do territ?rio protegido inserido na bacia. Entretanto, foram identificados locais priorit?rios para recupera??o e conserva??o da cobertura florestal, como em ?reas de mata ciliar e na zona de amortecimento da Reserva Biol?gica, essenciais para o equil?brio din?mico da bacia, caracterizada como de alta fragilidade/ susceptibilidade ? dist?rbios. Dessa forma, pretende-se fortalecer as condi??es de manejo adequadas e subsidiar projetos em que os processos de ocupa??o levem em conta conserva??o da natureza, fragilidade ambiental e conseq??ncias da degrada??o da Mata Atl?ntica sobre a biodiversidade e a qualidade de vida na bacia em estudo.
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Freudmann, Anita. "Phylogeography, habitat and resource use of Nyctimene robinsoni". Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/203859/1/Anita_Freudmann_Thesis.pdf.

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Fruit-eating bats play important roles in maintaining ecosystem health by contributing to seed dispersal and pollination. The current research aims to provide fundamental knowledge on the ecology and behaviour of the Queensland tube-nosed fruit bat (Nyctimene robinsoni). A field-based study investigated genetic variation across the currently known distribution range, and described habitat use, roosting ecology, foraging behaviour and dietary spectrum to evaluate the species' role as a seed disperser. Research outcomes contribute to a better understanding of the poorly understood group of Tube-nosed fruit bats, and findings can serve to support their conservation and species management.
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Laps, Rudi Ricardo. "Efeito da fragmentação e alteração do habitat na avifauna da região da Reserva Biologica de Una, Bahia". [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315763.

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Orientadores: Andre Victor Lucci Freitas, Keith Spalding Brown Junior
Tese (doutorado) Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: A Floresta Atlântica é um dos ecossistemas mais ameaçados no mundo e as unidades de conservação são importantes para manutenção da biodiversidade nesta paisagem altamente fragmentada. A avifauna da Floresta Atlântica do sul da Bahia é rica, com muitos endemismos e espécies ameaçadas de extinção. Nós investigamos a composição da avifauna da RBU e áreas adjacentes com o objetivo de medir a importância dessa UC para a proteção das espécies, assim como a resposta da comunidade aos diferentes hábitats (cabrucas, capoeiras e fragmentos florestais). Nós comparamos os resultados obtidos para aves, morcegos, lagartos, anuros e samambaias dentro dessa matriz predominatemente florestal com uma segunda área com paisagem oposta (fragmentos florestais imersos em matriz de cabrucas). Resultados: Nós encontramos 333 espécies de aves, incluindo 17 ameaçadas. A escassez de aves cinegéticas indica que a pressão de caça é alta na região. As cabrucas (plantações de cacau sob floresta raleada) exibem riqueza e abundância de aves maior que os demais hábitats investigados, com a presença de espécies generalistas invasoras. Frugívoros e insetívoros de copas foram abundantes e ricos nas cabrucas. Entretanto, insetívoros e frugívoros de sub-bosque são sensíveis à simplificação do hábitat deste sistema agroflorestal e muitas espécies desapareceram. O efeito de borda agiu significantemente para algumas espécies, com insetívoros generalistas aumentando sua riqueza e abundância, porém com alguns insetívoros e frugívoros de sub-bosque diminuindo próximo às bordas. Algumas espécies podem ser indicadores de florestas, já que ocorrem somente em interior de fragmentos. O amplo consenso sobre a importância de plantações sombreadas (cabrucas) para a conservação da biodiversidade deve ser tomado com cautela, porque algumas espécies evitam esse hábitat, mas as florestas secundárias (capoeiras) podem ser importantes para conectar fragmentos em uma paisagem. Uma comparação de pequenos fragmentos e cabrucas em duas paisagens contrastantes mostrou que a conversão de florestas em cabrucas impactaram diferentemente o padrão de dominância de espécies e guildas de aves e morcegos, porém as assembléias nas cabrucas geralmente refletem aquelas observadas em florestas próximas. A riqueza e composição de espécies foram diferentes nas paisagens analisadas, e ambos hábitats (florestas e cabrucas) de Uruçuca/Ilhéus mostraram perda de espécies florestais comparados com os mesmos hábitats em Una. Nosso estudo mostra que, apesar das cabrucas serem matrizes permeáveis para muitas espécies, elas não são substitutas das florestas. Há diferenças pronunciadas entre as duas paisagens com respeito à habilidade das cabrucas manterem a riqueza de espécies. Independente do grupo biológico considerado, uma representatividade maior de floresta nativa na paisagem influencia positivamente a riqueza de espécies encontradas nas cabrucas. O contexto da paisagem também influencia a variabilidade espacial da composição de espécies para alguns grupos biológicos, reforçando a importância e a vulnerabilidade de pequenas manchas florestais remanescentes em paisagens dominadas por cabrucas. Estes resultados apontam a necessidade de preservar áreas de hábitat primário mesmo em paisagens onde as práticas de uso da terra são geralmente favoráveis à conservação da biodiversidade
Abstract: The Brazilian Atlantic forest is one of more threatened ecosystems in the world, and the conservation units are very important in maintenance of biodiversity in a landscape highly fragmented. The avifauna of the Brazilian Atlantic Forest of southern Bahia State is very rich, with many endemisms and threatened species. We explore the composition of avifauna of UBR and adjacent areas, and investigated the bird communities in different habitats nearby UBR with aim to measure its importance for species protection. We compare these results obtained by birds, bats, lizards, frogs and ferns in a forested matrix with a second area with opposite landscape (forest fragments in a cabruca matrix). Results: We found 333 species, including 17 species threatened. The paucity of game birds, like cracids an tinamous, indicate that the hunt pressure is high in the region. The shaded cocoa plantation exhibited greater richness and abundance of birds, with the presence of generalist species that invaded this habitat. Canopy insectivores and frugivores were highly profuse in cocoa plantations. However, understory insectivores and frugivores are sensible to habitat simplification of this agroforest system, and many species vanished. Edge effect was significant for some species, with generalist insectivores showing increase in richness and abundance, but some understory insectivores and frugivores decrease near edges. Some species can be used as forest indicators, since it occurred only in interior of fragments. The widely consensus about the importance of shaded plantations for conservation of biodiversity must take in caution, because some species avoid this habitat, but the early secondary forest can be important to connect fragments in this highly patchy landscape. A comparison of small fragments and cabrucas from contrastant landscapes showed that the conversion of forest to cabrucas impacted the dominance pattern of species and guilds differently regarding birds and bats, but species assemblages in cabrucas generally reflect those observed in nearby forests. Species richness and composition were different in these landscapes, and both habitats from Uruçuca showed losses of forest-dwelling species compared with those habitats from Una. Our study has shown that, although cabrucas can be permeable matrices for many species from the local biota, they are not forest surrogates. There were pronounced differences between the two landscapes with regard to the ability of cabrucas to maintain species richness. Irrespective of the biological group considered, a greater representation of native forest in the landscape positively influences the species richness reported in cabrucas. Landscape context also influenced the spatial variability of species composition for some biological groups, stressing the importance, and the vulnerability of the small forest patches remaining in landscapes dominated by shade plantations. These results point to the need to preserve sufficient areas of primary habitat even in landscapes where land use practices are generally favorable to the conservation of biodiversity
Doutorado
Ecologia de Comunidades
Doutor em Ecologia
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Krepschi, Victor Gasperotto. "Caracterização da dieta da lontra neotropical (Lontra longicaudis, Carnivora: Mustelidae) em três rios de Mata Atlântica do Sul do Brasil: uma análise espacial e temporal". Universidade Estadual do Oeste do Parana, 2012. http://tede.unioeste.br:8080/tede/handle/tede/727.

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The diet of Otter longicaudis was characterized by fecal analysis and spatial and temporal aspects in their main prey consumption were analyzed. The study was conducted systematically in three rivers of the Iguaçu National Park, an Atlantic forest reserve located in southern Brazil. For a year, samples were taken monthly along three sections totaling 46 km, in order to find fecal samples. The analysis of 367 fecal samples collected showed a piscivorous diet, which includes four main fish families: Characidae Cichlidae, Pimelodidae and Loricariidae, with consumption of crustacean belonging to the family Trichodactilidae. Mollusks, birds, mammals, reptiles and insects were found in the diet. Seeds, vegetable fibers and materials of anthropogenic origin were also found. Differences in diet composition were found between the Iguaçu River and the other, which is probably related to the physical characteristics of these rivers reflecting distinct prey items available. The crabs were used as complementary resources for neotropical otters, when the consumption of their main prey (fish) decreased. An increased frequency of occurrence of prey categories was recorded in spring and summer, except for crabs and molluscs in two of the three rivers, which contrasts with the high consumption of fish during all seasons. Correlation was found between precipitation and consumption of fish families, which in turn seems to be due changings and the river otter and the habits of those arrested. In this region, otters depend on the features of the aquatic environment, forecasting the Mayor attention to the maintenance of rivers, shores and natural features (such as flow regimes and water), especially the river Gonçalves Dias, borders the east side of the National Park Iguaçu, with areas of heavy anthropogenic land use
A dieta de Lontra longicaudis foi caracterizada por análise fecal e aspectos espaciais e temporais no consumo de suas presas principais foram analisados. O estudo foi realizado sistematicamente em três rios do Parque Nacional do Iguaçu, uma reserva de Mata Atlântica localizado no sul do Brasil. Durante um ano, foram amostragens realizadas mensalmente ao longo de três trechos, totalizando 46 km, a fim de encontrar amostras fecais. A análise de 367 amostras fecais coletadas apresentaram uma dieta piscívoro, que inclui quatro principais famílias de peixes: Characidae, Cichlidae, Pimelodidae e Loricariidae, com consumo de crustáceo pertencente à família Trichodactilidae. Moluscos, aves, mamíferos, répteis e insetos foram detectados na dieta. Sementes, fibras vegetais e materiais de origem antrópica também foram encontradas. Diferenças na composição da dieta foram encontradas entre rio Iguaçu e os outros, que provavelmente está relacionado com as características físicas desses rios refletindo distinta presa disponibilidade itens. Os caranguejos foram utilizados como recursos complementares para as lontras neotropicais, quando o consumo de sua principal presa (peixes) diminuiu. Uma freqüência aumentado da ocorrência de categorias de presas foi registrada na primavera e no verão, com exceção de caranguejos e moluscos, em dois dos três rios, o que contrasta com o elevado consumo de peixes ao longo todas as estações. Correlação foi encontrada entre a precipitação eo consumo de famílias de peixes, o que por sua vez parece ser changings devido o rio e os hábitos da lontra e essas presas. Nesta região, as lontras dependem dos recursos do ambiente aquático, prevendo a atenção prefeito para a manutenção dos rios, margens e características naturais (como fluxo e regimes de água), em especial do rio Gonçalves Dias, fronteiras do leste lado do Parque Nacional do Iguaçu, com áreas de uso da terra pesada antrópica
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Ruiz, Winston Franz Rios. "Biogeografia de bactérias da filosfera de Maytenus robusta na Mata Atlântica". Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/11/11138/tde-14022011-084227/.

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A biogeografia estuda a distribuição dos organismos em relação ao espaço e ao tempo, favorecendo a compreensão dos mecanismos que geram e mantém a diversidade, especiação, extinção e dispersão das espécies. Dentre as florestas tropicais, a Mata Atlântica constitui um mosaico vegetal de grande diversidade, onde a filosfera representa um dos habitats mais comuns para os microrganismos. O objetivo do presente trabalho foi avaliar a estrutura e diversidade da comunidade bacteriana da filosfera de Maytenus robusta no Parque Estadual Carlos Botelho, Parque Estadual Ilha do Cardoso e Estação Ecológica de Assis, no estado de São Paulo, Brasil. As folhas foram coletadas em duas épocas do ano, seca e chuvosa. A estrutura da comunidade bacteriana foi avaliada através de PCR-DGGE da região V3 do gene rRNA 16S e a diversidade por sequenciamento da região V1-V3 do mesmo gene. A similaridade entre a estrutura de comunidades de Bacteria foi determinada com base na presença ou ausência das bandas detectadas no gel após PCR-DGGE. O agrupamento hierárquico gerado com o coeficiente de Jaccard e o método UPGMA mostrou a existência de comunidades bacterianas distintas na filosfera de M. robusta nas áreas amostradas. A existência de padrões biogeográficos foi determinada através de análises de regressão, usando os dados de similaridade da estrutura das comunidades bacterianas e os de distância geográfica entre as árvores amostradas. A correlação negativa observada nas avaliações fornece evidências para suportar a hipótese de que a similaridade entre as comunidades bacterianas da filosfera de plantas da mesma espécie diminui com o aumento da distância entre as árvores, dentro de um mesmo bioma. A avaliação espaço temporal da composição da comunidade bacteriana, realizada pela análise NMDS, demonstrou que houve efeito espacial mas no temporal na estrutura das comunidades bacterianas da filosfera de M. robusta. A afiliação taxonômica de 1.470 sequências de clones do gene rRNA 16S de Bacteria, obtidas da filosfera de M. Robusta, nas diferentes áreas e épocas, e a comparação múltipla das bibliotecas, mostraram que as comunidades bacterianas na filosfera foram distintas umas das outras, sendo os filos Proteobacteria e Acidobacteria os mais frequentes. Somente 1% das Unidades Taxonômicas Operacionais foram comuns entre os indivíduos avaliados. Com base nos resultados obtidos, pode-se inferir que, em cada bioma, plantas da mesma espécie possuem comunidades bacterianas únicas, sugerindo a existência de endemismo, altos níveis de especiação e baixa dispersão das comunidades bacterianas nas áreas avaliadas.
Biogeography studies the distribution of organisms in relation to space and time, favoring the understanding of the mechanisms that generate and keep the diversity, speciation, extinction and dispersion of species. Among the tropical forests, the Atlantic Forest constitutes a highly diverse vegetation mosaic, in which the phyllosphere represents one of the most common habitats for microorganisms. The goal of this work was to evaluate the structure and diversity of the bacterial community from the phyllosphere of Maytenus robusta in the Carlos Botelho State Park, Ilha do Cardoso State Park and Assis Ecologic Station, São Paulo state, Brazil. The leaves were collected in two different seasons of the year, dry season and rainy season. The structure of the bacterial community was evaluated through PCR-DGGE of the 16S rRNA gene V3 region, and the diversity by sequencing of the V1-V3 region of the same gene. The similarities between the structures of the bacterial community were determined based on the presence or absence of bands detected in the gels after PCR-DGGE. The hierarchical clustering generated using the Jaccard coefficient and the UPGMA method showed the existence of distinct bacterial communities in the M. robusta phyllosphere of the sampled areas. The existence of biogeographic patterns was determined through regression analyses, using the community structure similarity data geographic distance among the sampled trees. The negative correlation observed in most of the cases provides evidence to support the hypothesis that the similarity between the bacterial communities from phyllosphere of plants of the same species decreases as the distance among trees increased, within the same biome. The spacial-temporal evaluation of the structure of the bacterial communities, performed by the NMDS analyses, showed the occurrence of spacial but not temporal effects on the structure of the bacterial communities of M. robusta phyllosphere. The taxonomic affiliation of 1,470 bacterial 16S rRNA gene clones obtained from the M. robusta phyllosphere, in different areas and seasons, as well as the multiple comparisons of libraries showed that the bacterial communities in the phyllosphere were distinct from each other, and that Proteobacteria and Acidobacteria phyla were the most frequent. Only 1% of the bacterial Operational Taxonomic Units were common among the individuals evaluated. Based on the results obtained it is possible to conclude that, in each biome, plants of same species have unique bacterial communities, suggesting the existence of endemism, high levels of speciation and low dispersal of bacterial communities in the evaluated areas.
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Kefa, Christopher Amutabi. "Assessing the Impacts of Bioenergy Extraction and Human Land Use of the Biodiversity of Kakamega Tropical Rainforest, Kenya". Bowling Green State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1465254368.

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Vogliotti, Alexandre. "História natural de Mazama bororo (Artiodactyla; Cervidae) através de etnozoologia, monitoramento fotográfico e rádio-telemetria". Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/91/91131/tde-29072004-161012/.

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A espécie Mazama bororo foi proposta em 1996 com base no cariótipo exclusivo (2n=32-34) encontrado em alguns animais de cativeiro. O presente estudo teve início em 1998, com os objetivos de confirmar a ocorrência da espécie na natureza, desenvolver metodologias de captura adequadas aos cervídeos de ambientes florestais e obter informações ecológicas básicas através da etnozoologia, do uso de armadilhas fotográficas e do monitoramento de animais marcados com rádio-colares. As pesquisas ocorreram em diferentes municípios e unidades de conservação públicas ou privadas ao longo da Serra de Paranapiacaba, região sul de São Paulo. As entrevistas realizadas com caçadores e palmiteiros da região indicaram a existência de 3 espécies de Mazama: M. americana, M. gouazoubira e M. bororo, além de fornecer informações gerais sobre sua ecologia, comportamento, dieta, reprodução e as técnicas de caça normalmente empregadas na região. Através das armadilhas fotográficas foi possível observar hábitos crepusculares e noturnos em M. bororo e detectar alguns padrões de utilização do habitat, possivelmente relacionados a estratégias anti-predatórias, reprodução e disponibilidade de recursos ao longo do ano. As diversas técnicas de captura empregadas apresentaram índices muito baixos de captura, a despeito do esforço relativamente alto investido nas tentativas. As técnicas de interceptação, utilizando armadilhas fixas ou desmontáveis foram as mais eficientes, resultando na captura de 4 animais. Foram estimadas áreas de uso para dois M. bororo (fêmeas) e um M. gouazoubira (macho) no interior e entorno do Parque Estadual Intervales (PEI), através da rádio-telemetria. As áreas de M. bororo foram consideravelmente menores e cobertas por vegetação nativa em bom estado de conservação enquanto que o M. gouazoubira ocupou áreas bastante antropizadas, indicando preferências de habitat distintas entre estas espécies. Evidências não comprovadas da existência de M. americana na região levantam questões relevantes acerca da conservação de M. bororo e apontam a extrema necessidade de estudos mais intensivos visando confirmar essa simpatria, determinar os nichos de cada espécie e principalmente definir a distribuição geográfica de M. bororo nos últimos remanescentes de Mata Atlântica do país.
The species Mazama bororo was proposed in 1996 based on the unique karyotype (2n=32-34) found in some captive animals. The present study began in 1998 and intended to confirm the occurrence of this species in nature as well as to develop deer capture methods adequate in forest environments and to obtain basic ecological information using etnozoological approach, camera traps and radio-collared animals. For this purpose research was carried out several in municipalities and in public or private conservation units along the Paranapiacaba Ridge, southern region of São Paulo State, Brazil. Interviews accomplished with hunters and heart of palm gatherers from this region indicated the existence of 3 Mazama's species: M. americana, M. gouazoubira and M. bororo. These interviews also supplied general information about the ecology, behavior, diet and reproduction of these deer species and the hunting techniques employed in the region. Camera traps allowed the observation of the twilight and nocturnal habits of M. bororo and of some patterns of habitat utilization, probably related to anti-predatory strategies, reproduction and resources availability along the year. In spite of the intense efforts, all techniques employed for capture in this study had a low capture index. The interception technique, using fixed or dismountable traps and resulting in the capture of 4 animals, was the most efficient. Home ranges of two M. bororo (females) and a M. gouazoubira (male) were estimated in the Intervales State Park (PEI) and it’s outskirts by radio-telemetry. The home ranges of M. bororo were considerably smaller and covered by well preserved native vegetation. M. gouazoubira many times occupied degraded areas, indicating distinct habitat preferences between these species. Not proven evidences of the existence of M. americana in the studied region rise important questions regarding M. bororo preservation; there is an urgent need for intensive studies to confirm this simpatry, to determine the niches of both species and to define the geographical distribution of Mazama bororo in the last Atlantic Rain Forest remainders of the Brazil.
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Arnhem, Eric. "Eco-ethological response of great apes and other rainforest mammals to selective logging in Cameroon". Doctoral thesis, Universite Libre de Bruxelles, 2008. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210369.

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With more than ¾ of the forest surface of Cameroon allocated to logging, the survival of many rainforest species will depend on the way in which timber production forests will be managed in this country for the next decades. Management decisions to be applied should be directed systematically towards a minimization of the negative impacts on the ecosystem as a whole, including on the animal populations living in these forests. This requires a detailed understanding of the response of wildlife to selective logging as it is currently practised in Central Africa.

This thesis reports results of a longitudinal monitoring of abundances of nine mammal species in a forest concession over a four years period. From 2003 to 2006, four wildlife censuses have been conducted in the active core of FMU 10.030 allocated to the logging company PALLISCO. Our study area covers 176 sq-km and include several logging compartments and unlogged areas.

The diversity of specific responses to the introduction of human activities into the habitat is at the scale of the biological diversity of the habitat itself. A particular attention was paid to two emblematic species of the Cameroonian forests, western lowland gorillas G.g. gorilla and the common chimpanzees Pan troglodytes. During this work, we studied 1) how logging at industrial scale affects the spatial distribution of nine mammal species, including great apes, in timber production forests of South-eastern Cameroon, and 2) the nature of pressures exerted on animal populations within an active forest concession (anthropic, ecological, ethologic, etc).

Our first results indicate that the extraction of valuable timber species generates a spatial reorganization of gorillas and chimpanzees, inducing local modifications of population densities. This spatial reorganization seems to be mainly due to human activities per se rather than to modifications of the habitat structure or changes in the availability of fruits for these species. Compared with other mammals, great apes are at the two extreme opposites of a gradient of sensitivity to the habitat disturbances created by logging. Gorillas, as well as other "generalist" species like duikers, seem to thrive in logged forests, probably attracted in these areas by the secondarisation of the vegetation. Their densities decrease temporarily in logging compartments during logging operations but these species recover quickly, suggesting a repulsive effect of the human presence in the forest rather than a major alteration of the habitat quality for them. Rather "specialist" species seem to react by increasing the size of their foraging area. These are the sitatungas Tragelpahus spekei and bushpigs Potamochoerus porcus, two typical species of swamp forest with Raffia spp. and semi-inundated forests. These particular biotopes in the heart of the production forests seem to be playing the role of refuge zone for these species. Finally, two species were identified as being explicitly vulnerable to logging activities: the chimpanzees and forest elephants Loxodonta africana cyclotis. Their abundances did not recover to original values during the period of study indicating that they still undergo some kind of ecological and/or anthropic pressures after the end of logging operations that is strongly adverse to them.

In order to contrast the ecological and/or anthropic factors ruling gorillas' and chimpanzees' spatial distribution in the habitat, we have used a spatial modelling technique called “Ecological Niche Factor Analysis - ENFA". ENFA-generated models for these two species mainly retained anthropic variables to explain great apes local repartition in the study area. For gorillas, it was mainly explained by the local pattern of logging compartments and the time that passed since the end of logging operations. Globally, this species avoids the areas of forests showing a high rate of human frequentation and is attracted to old logged areas. As for the chimpanzees, their spatial distribution is influenced mainly by the presence of roads which are largely avoided. The periphery of logged compartment seems to be a zone of convergence for chimpanzee communities that have probably been driven out from logging compartments during operations, but these movements of populations would be limited to short distances. The vulnerability of the chimpanzees is consequently explained by the absence of demographic mechanisms enabling them to avoid the disturbed zones while reducing the territorial conflicts.

The general trend in great ape abundances in an active logging concession confirms that even closely related species can show divergent capacities of survival when confronted to human disturbances. Our work highlights that chimpanzee communities demonstrate some spatial inertia, contrarily to gorillas which easily manage to avoid human activities. This inertia would be probably at the origin of its sensitivity to current forestry practices. Our results confirm White & Tutin (2001)'s socio-ecological explanation for the vulnerability of chimpanzees to logging in forests of Central Africa. Knowing this, it is imperative to set up concrete conservation actions aiming at maintaining the chimpanzee populations of in Cameroonian timber production forests.

Practically, selective logging would easily be compatible with the preservation of the majority of rainforests mammals if concrete measures aiming at decreasing the negative impacts of logging were effectively applied. As a general rule, the proximity between logged areas and some zones that can serve as refuge seems to be a determining factor of the persistence of rainforests mammals in logged forests. A line of thought would be thus to ensure safe shifts of populations towards these zones in order to guarantee the avoidance of disturbances and, later, the recovery of densities in logged forests. In this sense, our main recommendation consists in promoting a delimitation of logging compartments into narrow strips so as to reduce the distance to be walked by an animal to geographically avoid human disturbances. Additionally, it is necessary to set up well-designed biomonitoring programmes to follow up trends in wildlife abundances and promote a flexible management that can be adapted according to the evidence of detrimental events to wildlife.

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Avec plus de ¾ de la surface forestière du Cameroun allouée à l'exploitation forestière, la survie de nombreuses espèces de mammifères dépendra de la façon dont seront gérés les massifs de forêt de production de ce pays dans les décennies à venir. Les mesures de gestion à appliquer devraient être orientées systématiquement vers une minimisation des impacts négatifs sur l'écosystème dans son ensemble, y compris sur les populations animales résidant dans ces forêts. Ceci nécessite une compréhension détaillée de la réponse de la grande et moyenne faune à l'exploitation forestière sélective telle qu'elle est effectivement pratiquée en Afrique Centrale.

Cette thèse de doctorat rapporte les résultats d'un suivi longitudinal, sur une période de quatre ans, des abondances de neuf espèces de mammifères au sein d'une concession forestière du Sud-est Cameroun. Au total, quatre recensements de la faune ont été réalisés entre 2003 et 2006 dans la partie active de l'UFA 10.030 allouée à la société PALLISCO. La zone étudiée couvre 176 km2 et englobe plusieurs parcelles annuelles d'abattage ainsi que des compartiments non exploités.

La diversité des réponses spécifiques vis-à-vis de l'introduction d'activités humaines dans l'habitat est à l'échelle de la diversité biologique de l'habitat lui-même. Une attention particulière a été portée sur deux espèces emblématiques des forêts camerounaises, les gorilles des plaines occidentales G.g. gorilla et les chimpanzés communs Pan t. troglodytes. Durant ce travail, nous avons étudié 1) comment l'exploitation forestière à l'échelle industrielle affecte la distribution spatiale de neuf espèces de mammifères, dont les grands singes, dans les massifs de forêt de production du Sud-est Cameroun, et 2) de quelle nature sont les pressions exercées sur les populations animales au sein d'une concession forestière active (anthropique, écologique, éthologique, etc.).

Nos premiers résultats indiquent que l'extraction d'essences précieuses dans les forêts camerounaises génère notamment une réorganisation de la distribution spatiale des gorilles et des chimpanzés, induisant des modifications locales de densité de population. Cette réorganisation spatiale semble être due aux activités humaines elles-mêmes plutôt qu'aux modifications de la structure de l'habitat ou à une diminution de la disponibilité de certaines ressources alimentaires importantes pour ces espèces. Comparés à d'autres mammifères, les grands singes se placent aux deux extrêmes d'un gradient de sensibilité aux perturbations de l'habitat causés par l'exploitation forestière. Les gorilles, ainsi que d'autres espèces "généralistes" comme les céphalophes, semblent prospérer dans les forêts exploitées, probablement attirés dans ces zones par la secondarisation de la végétation. Leurs densités diminuent ponctuellement dans les parcelles d'abattage pendant les opérations d'extraction, mais retrouvent très vite leur niveau initial. Ceci suggère un effet répulsif de la présence humaine sur ces espèces plutôt qu'une altération majeure de la qualité de l'habitat pour ces dernières. D'autres espèces plus "spécialistes" semblent réagir en augmentant la taille de leurs aires de fourragement. Il s'agit des sitatungas Tragelpahus spekei et des potamochères Potamochoerus porcus, deux espèces appréciant les biotopes humides (marécages à Raphia spp. des zones de forêt inondées, etc.). Ces biotopes particuliers, non-affectés par l'exploitation forestière, au coeur des forêts de production semblent servir de refuge pour ces espèces. Enfin, deux espèces ont été identifiées comme étant explicitement très vulnérables aux activités d'exploitation: les chimpanzés et les éléphants des forêts Loxodonta africana cyclotis. Leurs abondances n'ont pas recouvré les valeurs originelles durant la période d'étude, indiquant que ces espèces subissent encore des pressions écologiques et/ou anthropiques jusqu'à quatre ans après la fin des activités d'exploitation forestière.

Afin de contraster les facteurs écologiques et/ou anthropiques régissant la distribution spatiale des gorilles et des chimpanzés, nous avons fait usage d'une technique de modélisation spatiale appelée "Ecological Niche Factor Analysis – ENFA". Les modèles ENFA pour ces deux espèces ont principalement retenu les variables anthropiques pour expliquer la distribution spatiale des grands singes dans l'aire d'étude. Il a ainsi été démontré que la répartition des gorilles était en grande partie expliquée par l'agencement local des AACs et le temps qui s'est écoulé depuis la fin des opérations d'extraction dans celles-ci. De manière générale, cette espèce évite les zones présentant un haut taux de fréquentation humaine et préfère les forêts exploitées quelques années auparavant. Quant aux chimpanzés, leur distribution spatiale est principalement expliquée par la présence de routes et pistes forestières qui sont amplement évitées. La périphérie des zones exploitées semble être une zone de convergence pour les chimpanzés qui y seraient vraisemblablement refoulés lors des perturbations, mais ces mouvements seraient limités à de courtes distances. La vulnérabilité des chimpanzés s'expliquerait dès lors par l'absence de mécanismes démographiques leur permettant d'éviter les zones affectées tout en réduisant les conflits territoriaux résultant d'une réorganisation spatiale.

La tendance globale des variations d'abondance des grands singes au sein d'une concession forestière en cours d'exploitation confirme que même des espèces très proches phylogénétiquement peuvent faire preuve de capacités différentes de survie face aux perturbations anthropiques. Il ressort de nos observations que les communautés de chimpanzés font preuve d'une certaine inertie spatiale, contrairement aux gorilles qui parviennent à éviter les activités humaines. Cette inertie serait probablement à l'origine de sa vulnérabilité face aux pratiques forestières actuelles. Nos résultats viennent confirmer l'hypothèse socio-écologique émise par White & Tutin (2001). Face à ce malheureux constat, il est impératif de mettre en place des mesures concrètes de gestion visant à maintenir les populations de chimpanzés dans les forêts de production camerounaises.

Pratiquement, l'exploitation sélective serait compatible avec la conservation de la plupart des mammifères si certaines mesures de gestion visant à diminuer les impacts négatifs étaient rapidement mises en application. La proximité entre les zones exploitées et les zones pouvant servir de refuge semble être un facteur déterminant de la survie de nombreuses espèces de mammifères dans les forêts de production du Cameroun. Une ligne de réflexion serait donc d'assurer les mouvements de populations vers ces zones-refuge sans heurts afin de garantir l'émigration des populations animales en dehors des zones affectées et la recolonisation ultérieure des forêts exploitées. En ce sens, notre principale recommandation consiste à promouvoir un découpage en assiettes de coupe en bandes relativement étroites (<2,5 km) de façon à réduire la distance à parcourir pour éviter géographiquement les perturbations anthropiques. De même, il serait nécessaire de mettre en place des programmes de suivi régulier des abondances faunistiques afin de permettre une gestion adaptative qui s'ajusterait au vu d'événements critiques pour la faune.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished

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44

Narezi, Gabriela. "A agroecologia como estratégia de gestão de Unidades de Conservação de Uso Sustentável no Vale do Ribeira − SP, Brasil". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/91/91131/tde-21122012-101140/.

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Este trabalho apresenta elementos de reflexões acerca dos distintos modelos de gestão que são concebidos para as áreas naturais protegidas. Nosso interesse se voltou, em particular, para os debates acerca das Unidades de Conservação de Uso Sustentável do estado de São Paulo - Brasil. Atualmente, na região do Vale do Ribeira, possuidora de um dos maiores remanescentes contínuos de Mata Atlântica do país, é possível encontrar disputas por diferentes modelos de gestão destas áreas. O estudo da implantação das Reservas de Desenvolvimento Sustentável (RDS) permite analisar as mais recentes formas de reconhecimento do direito de permanência de populações tradicionais no interior de áreas naturais protegidas no Brasil, em especial, na faixa de Mata Atlântica do litoral sul paulista. Nesta perspectiva, buscou-se analisar a inserção da temática da agroecologia como estratégia de gestão, em meio a conflitos socioambientais. A metodologia de pesquisa comportou levantamento bibliográfico e coleta de dados primários, graças a anotações em cadernos de campo, obtenção de relatos orais nos espaços participativos de gestão e uso do território da RDS do Despraiado, no âmbito da recategorização da Estação Ecológica Juréia-Itatins em mosaicos de UCs e entrevistas semi-estruturadas junto aos gestores e pesquisadores das UCs do Vale do Ribeira. A pesquisa ainda contou com um estágio doutoral no Institute des Hautes Études sur l\'Amerique latine, Sorbonne Nouvelle, onde foi possível analisar as estratégias de gestão territorial adotadas em dois Parques Naturais Regionais franceses, consideradas enquanto subsídio para nossa análise sobre a conciliação da conservação com o desenvolvimento. A partir dos dados coletados foi possível caracterizar e interpretar a organização social, o histórico das práticas produtivas agrícolas tradicionais, os conflitos socioambientais ligados à gestão da RDS do Despraiado e as práticas agrícolas intensivas em áreas degradadas. Neste quadro, foi possível encontrar evidências de que o modo de vida e de produção agrícola favorecem uma sensibilidade das populações locais ao início de um processo de transição agroecológica. Entretanto, as disputas em torno da implantação da RDS em estudo aqui revelam que a perspectiva de conservação da natureza com desenvolvimento - na qual a agroecologia está, em princípio, em primeiro plano - enfrenta muitos obstáculos para sua disseminação. A promulgação da Ação Direta de Inconstitucionalidade contra a lei que instituiu o Mosaico de UCs Juréia-Itatins reforça a manifestação dos interesses preservacionistas no âmbito da gestão deste território no estado de São Paulo. Mesmo com a repercussão de experiências agroecológicas de sucesso no Vale do Ribeira, ainda são muito incipientes as iniciativas de conservação da sociobiodiversidade e de valorização cultural para o desenvolvimento sustentável das populações tradicionais no interior de UCs paulistas.
This paper presents reflections regarding different management models designed for protected natural areas. Our research is particularly focused in debates about Sustainable Conservation Units in Sao Paulo State in Brazil. Vale do Ribeira is an area that has one of the largest continuous remnants of Atlantic Rainforest of the country. There are several disputes over different management models for those areas. The study of Sustainable Development Reserves (Reservas de Desenvolvimento Sustentável - RDS) implementation allows analyzing the latest forms of recognition of the right of residence of traditional populations within protected natural areas in Brazil, especially in the Atlantic rainforest in the southern coastal area of Sao Paulo state. In this perspective, this study sought to analyze the integration of agroecology as a management strategy amid environmental conflicts. The research methodology included bibliographic analysis and collection of primary data through field notes; oral histories obtained in management and land use participatory spaces at Despraiado RDS in the context of restructuration of Juréia- Itatins Ecological Station in Conservation Units Mosaics; and semi-structured interviews with the managers and researchers of Vale do Ribeira Conservation Units. The research also included a doctoral internship at Institute des Hautes Études sur l\'Amerique latine, at Université Sorbonne Nouvelle, in France where it was possible to analyze the strategies of land management practices of two French Regional Natural Parks. That experience was the base to analyze the conciliation between conservation and development in this study. From the data collected it was possible to characterize and interpret the social organization, the history of traditional agricultural production practices, of environmental conflicts related to the management of Despraiado RDS and intensive agricultural practices in degraded areas. In this context, it was possible to find evidence that the way of life and agricultural production of the area favor local sensitivity in regard of an agroecological transition process. However, the disputes over the implementation of the RDS analyzed in this study, shows that the perspective of nature conservation along with development faces many obstacles to its propagation even though agroecology is in the forefront of the discussion. The enactment of the lawsuit declaring the creation of Juréia-Itatins Conservation Unit Mosaic an unconstitutional act, reinforces the manifestation of preservationists\' interests in the management of this Sao Paulo State territory. Even with the impact of successful agroecological experiences at Vale do Ribeira, socio-biodiversity conservation initiatives and cultural valorization of sustainable development of traditional populations are still rudimentary at Conservation Units in the State of Sao Paulo.
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45

Stark, Scott C. "On the Mechanistic Connection of Forest Canopy Structure with Productivity and Demography in the Amazon". Diss., The University of Arizona, 2012. http://hdl.handle.net/10150/265347.

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Canopy structure has long been thought to influence the productivity and ecological dynamics of tropical forests by altering the availability of light to leaves. Theories and methods that can connect detailed quantitative observations of canopy structure with forest dynamics, however, have been lacking. There is urgent need to resolve this uncertainty because human-caused climate change may alter canopy structure and function in the Amazon. This work addresses this problem by, first, developing methods based on LiDAR remote sensing of fine-scale structural variation to predict the spatial structure of leaf area and light in forest canopies of the central Amazon (Appendices B&C). I show that LiDAR-based leaf area and light estimates can be used to predict the productivity of tree size groups and one-hectare forest plots--as well as differences between 2 sites separated by 500km (App. B). Sites also differed in canopy structure and the distribution of tree frequencies over size (size or diameter distribution). A model based on tree architecture, however, was able to connect observed differences in canopy architecture with size distributions to predict plot and site differences (App. D). This model showed that tree architecture is plastic in different light environments. While plasticity may increase light absorption, the smallest size groups appeared light limited. Absorption over size groups in one site, but not the other, agreed with the hypothesis of energetic equivalence across size structure. Ultimately, the performance of individual trees of different sizes in different canopy environments links forest demography with canopy structure and ecosystem function--I present a study aimed at improving tests of individual level theories for the role of light dependence in tree growth (App. A). Together, this work quantitatively connects canopy structure with forest carbon dynamics and demographic structure and further develops LiDAR as premier tool for studying forest ecological dynamics. Assessing variation in biomass growth and demographic structure over tropical landscapes with remote sensing will improve understanding of ecosystem function and the role of the Amazon in global Carbon dynamics.
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46

Jeffs, Christopher. "Natural enemies and the diversity of plant communities". Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:49c80db9-6590-4e06-b86f-24d225046969.

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The processes that determine the structure of plant communities are of considerable practical and theoretical interest. Natural enemies such as herbivores, seed predators and pathogens provide one potentially important influence on plant diversity. I investigated the effects of natural enemies on plant diversity in two contrasting, species-rich plant communities (tropical forests in Panama and temperate grasslands in the UK), focusing on pre-dispersal seed predation by insects, and the mortality of seeds and seedlings caused by soil fungi. In Panama I found that pre-dispersal insect seed predators generate significant levels of mortality in multiple tropical tree species, with high heterogeneity in predation rates among individuals and at different forest sites. Insect seed predators were highly host-specific, consistent with a role in enhancing plant diversity. At Upper Seeds, a calcareous grassland site in the UK, I used manipulative experiments to show that soil fungi increase the diversity of plants propagating from soil seed banks. A parallel experiment in Panama, mimicking germination under light gap conditions, revealed differential effects of fungi among sites, with fungicide treatment appearing to increase the diversity of propagated seedlings at some sites but reducing it at others. These results suggest that the influence of soil fungi on pre-emergence mortality can alter plant diversity, even when post-emergence mortality from fungal pathogens is limited. In Panama, I also tested whether enemy-mediated mortality increases with rainfall, potentially contributing to the positive regional correlations widely observed between precipitation and plant diversity. In contrast to predictions, neither pre-dispersal insect seed predation nor the influence of soil fungi on seedling recruitment were affected significantly by site humidity, or (for soil fungi) with experimentally manipulated soil moisture levels. Overall, my results provide evidence that pre-dispersal seed predators and soil fungi can affect plant recruitment and diversity at early life stages, with potential consequences for the community structure of adult plants.
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47

Quitmeyer, Andrew J. "Digital naturalism: Designing a digital media framework to support ethological exploration". Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54327.

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This research aims to develop and evaluate a design framework for creating digital devices that support the exploration of animal behaviors in the wild. In order to carry out this work, it both studies ethology’s foundational ideas through literature and also examines the contemporary principles at a rainforest field station through on-site ethnographies, workshops, design projects, and interactive performances. Based upon these personal and practical investigations, this research then synthesizes a framework to support digital-ethological practice. Finally, this framework is utilized to design additional ethological expeditions and activities in order to assess the framework itself. The resulting framework encourages digital technology that supports four key concepts. Technological Agency pushes for devices that promote understanding of their own internal functions. The tenet of Contextual Crafting leads designers and ethologists to create devices in close proximity to their intended use. Behavioral Immersion promotes visceral interactions between the digital and organismal agents involved. Finally, Open-Endedness challenges researchers to create adaptable tools which strive to generate questions rather than answering them. Overall, this research, referred to as Digital Naturalism, explores a developing design space for computers in the wild.
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48

Prado, Vânia Luísa Spressola. "Ecologia Política da comida e nutrição em duas comunidades quilombolas do Vale do Ribeira (Estado de São Paulo, Brasil)". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/41/41134/tde-06062011-073004/.

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Quilombolas são descendentes de escravos africanos. Os quilombolas do Ribeira estão estabelecidos em áreas remotas ao longo da Bacia do Rio Ribeira de Iguape (sul do Brasil), cobertas pela vegetação da Mata Atlântica, um dos hotspots de biodiversidade do mundo. Desde os primórdios da ocupação (século XVIII), os quilombolas tem sido historicamente dependentes do cultivo de arroz, milho, mandioca e feijão pelo sistema de corte-e-queima. No entanto, desde a década de 1970, seus estilos de vida vem sendo profundamente alterados por mudanças da economia-política regional como, por exemplo, a construção de estradas e escolas rurais, o estabelecimento de áreas de conservação na região e pela implementação de programas governamentais de transferência de renda. Assim, algumas tendências locais consistem no aumento da renda e na substituição do cultivo de corte-e-queima pela intensificação agrícola e trabalho assalariado. Para compreendermos como as mudanças nas estratégias produtivas podem estar interagindo com os padrões nutricionais locais, coletamos dados de dieta, antropometria e alocação de tempo dos indivíduos de duas comunidades quilombolas peri-urbanas/rurais. As pessoas da primeira comunidade encontram-se mais voltadas para o plantio de cultívares comerciais, trabalho assalariado e artesanato do que aquelas da segunda, que orientam suas atividades produtivas sobretudo para a agricultura de subsistência e para o extrativismo de produtos florestais não madeireiros. Apesar das diferenças nas estratégias produtivas, encontramos os mesmos padrões de dieta e de atividade física em ambas as comunidades: seus núcleos calórico-proteicos parecem ser constituídos por comidas ricas em calorias, processadas ou provenientes de animais domesticados e em ambas as comunidades parece haver uma tendência de redução quanto à demanda energética associada às atividades produtivas a ocorrência simultânea destas tendências caracterizam a ocorrência de um processo demográfico mais amplo chamado Transição Nutricional (TN) (Popkin e Gordon-Larsen, 2004). Em conclusão, nossos dados sugerem que independentemente da estratégia produtiva adotada, ambas as comunidades passam por de TN e que as mulheres vêm sendo mais impactadas pelo processo do que os homens, em razão destes últimos, provavelmente, ainda se manterem envolvidos, em algum nível, com atividades agrícolas. Os programas governamentais de transferência de renda (bolsa-família) podem ser relevantes na definição das similaridades nos padrões de consumo alimentar encontrados.
Quilombolas are African slave descendants. The Ribeira Valley is one of the most important areas of concentration of Quilombos in Southern Brazil. The Ribeira Quilombolas are settled in remote areas along the Ribeira River system covered by Atlantic rain forest vegetation, one of the worlds biodiversity hotspots. Since the first settlements (18th Century), they have been historically dependent on shifting cultivation of rice, maize, manioc and beans. However, since 1970\'s their life style has been profoundely affected by changes in regional political economy, such as the opening of a roadway, the establishment of conservation areas in the region and the setting-up of rural schools. Some of the local trends consist of replacing shifting cultivation and increasing household income mainly through agricultural intensification, wage labour and government cash transfer programs. In order to grasp the way changes in economic strategies have affected the nutritional patterns, we collected data of diet, anthropometry and time allocation of individuals from two Quilombola peri-urban/rural communities. People from the first community have become more oriented to commercial crops, wage labor and handicrafts than people from the other one, still more tied to subsistence agriculture and the gathering of non-timber forestall products. Despite the differences in productive strategies, we found the same diet and physical activity patterns: the energy-protein core consisted of the same energy rich and processed foodstuff or foods from domesticated animals, and Quilombolas seem to have had their energy demands reduced, probably because of the decrease of agricultural activities. However, only men are still significantly involved in agricultural oriented activities. We concluded that regardless of the economic strategy adopted, both communities are undergone Nutrition Transition process (a global trend that consists of increasing the comsumption of energy rich foodstuff and of decreasing of energy expenditure levels (Popkin e Gordon-Larsen, 2004)) and women might be more impacted by the process than men. Additionally, government cash transfer programs seem to affect the diet and physical activities patterns found.
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49

Guitet, Stéphane. "Diversité des écosystèmes forestiers de Guyane française : distribution, déterminants et conséquences en termes de services écosystémiques". Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS183/document.

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Le massif forestier guyanais présente à la fois une grande originalité en termes de biodiversité, un bon état de conservation, une forte contribution au stock de carbone amazonien et une dynamique socio-économique très rapide. Les connaissances sur la diversité des écosystèmes forestiers de Guyane française restent cependant insuffisantes pour asseoir une gestion optimale des différents services écosystémiques à l’échelle du territoire. Les travaux réalisés dans le cadre de cette thèse, visent prioritairement à étudier la diversité des écosystèmes forestiers de Guyane, les facteurs déterminant leur variabilité et les conséquences de cette variabilité en termes de services écosystémiques et de gestion.La première partie de la thèse met en évidence les différentes échelles de structuration spatiale de la diversité forestière et les patrons de composition qui en résultent à l’échelle régionale. Elle s’appuie sur une récente campagne d’inventaires forestiers (2006-2013) couvrant l’ensemble du département et rassemblant 3 132 placettes de 0.2ha implantées selon un plan d’échantillonnage emboîté et pluristratifié. Les résultats obtenus vérifient l’hypothèse d’une forte influence de la géomorphologie, à l’échelle des paysages, sur la bêta et l’alpha-diversité des forêts guyanaises en termes d’espèces dominantes (métrique de Simpson). Cette première étape a nécessité plusieurs développements méthodologiques préalables notamment l’évaluation de l’incertitude taxonomique des inventaires forestiers et sa propagation dans les analyses de diversité, ainsi que l’élaboration de modèles cartographiques permettant de caractériser précisément l’environnement géomorphologique à diverses échelles d’études.La deuxième partie de la thèse vise à expliquer l’influence exercée par les paysages géomorphologiques sur la végétation forestière à travers l’étude des relations entre géomorphologie et sols. Elle s’appuie sur l’analyse de près de 450 sondages pédologiques couplés à la campagne d’inventaire forestier. Les résultats obtenus démontrent une forte dépendance de la nature et des propriétés des sols vis-à-vis des paysages géomorphologiques et du dénivelé régional. Ils suggèrent l’existence d’un effet de filtre édaphique sous-jacent au déterminisme géomorphologique sur la diversité forestière. Une part importante de l’influence géomorphologique reste cependant indépendante du filtre édaphique et est interprétée comme un effet conjugué de deux autres mécanismes sur deux échelles de temps distinctes : le contrôle du turn-over forestier par la dynamique géomorphologique au cours du quaternaire récent et l’intégration des effets biogéographiques sous l’influence des changements globaux plus anciens.La troisième partie de la thèse s’intéresse aux conséquences de la diversité biotique et abiotique décrite sur la gestion forestière et sur la variabilité des services écosystémiques rendus par la forêt, notamment en termes de stockage du carbone dans la biomasse et dans les sols. La quantité de carbone stockée, très variable à l’échelle locale, se révèle significativement influencée par la diversité écosystémique à l’échelle régionale. Ce service de régulation est mis en relation avec la richesse spécifique locale (service de support) et la quantité de bois exploitable (service d’approvisionnement). Des relations complexes de corrélation et de compromis sont mises en évidence entre ces différents services. Elles illustrent la variabilité des réponses des services écosystémiques à la diversité des écosystèmes forestières.La mise en perspective de ces différents volets permet de proposer une typologie précise des habitats forestiers de Guyane et de fournir des pistes de prise en compte de cette diversité écosystémique pour l’aménagement du territoire et la gestion forestière
French Guiana forest presents a high originality in terms of biodiversity, a good state of preservation, a strong contribution to the overall Amazonian carbon stocks and a very fast socio-economic dynamic. However, our knowledge about forest ecosystems diversity remains insufficient to ensure an optimal management of the various ecosystems and of the services they may provide across the territory. This thesis aims to answer this central issue by studying the diversity of forest ecosystems at the scale of the entire forested area of French Guiana. Specifically we targeted highlighting the factors that determine ecosystems variability and evaluating the consequences of this variability in terms of ecosystem services and management.Firstly, we bring out complex patterns of diversity at different scales including strong floristic variation at the regional scale, using a recent forest inventories campaign (2006-2013) that has been conducted according to a stratified sampling design which includes 3,132 0.2ha-plots covering the whole territory. Our results verify the hypothesis of a strong control of forest beta and alpha diversity by geomorphology, especially at the landscape scale and for dominant species (Simpson metric). This first step required several preliminary methodological developments including an assessment of the taxonomic uncertainty in forest inventories, and spatial models to accurately characterize the geomorphological context at various scales.Secondly, we aimed at interpreting the influence of geomorphological landscapes on the composition of forest vegetation by exploring the relationship between geomorphology and soils. Using about 450 soil sampling locations coupled with the forest inventory plots, we demonstrated that nature and properties of soils are dependent on geomorphological landscapes and locally distributed along regional elevation gradients. A significant soil filtering effect was found underlying the geomorphological influence on forest composition and diversity. However, a major part of this influence proved to be independent of soil filtering and is interpreted as a combination of two mechanisms at two different time-scales: (i) the control of forest turn-over by the geomorphological dynamics during the Late Quaternary and (ii) the integration of biogeographic effects under the influence of tectonic evolution and ancient climate changes.Last of all, we addressed the consequences of the analysed biotic and abiotic variations, which combine into habitats diversity on forest management and on the variability of ecosystem services provided by forests, particularly for carbon storage in biomass and soils. The amount of carbon stored is highly variable at local scale but proves to be significantly influenced by habitats diversity at the landscape level. This regulation service is related with the local species richness (pertaining to the category of support services) and the amount of usable wood (pertaining to the category of supply services). Complex relationships, including correlations and compromises, are evidenced between these different services. This illustrates the variability of the responses of ecosystem services to the habitats diversity.Finally our work allowed us to provide a new typology of natural habitats present in French Guiana forest and to propose suggestions in order to improve land uses and multifunctional forest management in French Guiana
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50

Aubry-Kientz, Mélaine. "Quelle sera la réponse des forêts tropicales humides à l’augmentation des températures et aux changements de pluviométrie ? : Modéliser la dynamique forestière pour identifier les processus sensibles en Guyane française". Thesis, Antilles-Guyane, 2014. http://www.theses.fr/2014AGUY0802/document.

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En 2013, Le Groupe d'experts Intergouvernemental sur l'Evolution du Climat (GIEC) publie son cinquième rapport concernant les changements climatiques. Il y est souligné que le réchauffement climatique est sans équivoque, et que de nouvelles émissions de gaz à effet de serre impliqueront une poursuite du réchauffement et des changements affectant toutes les composantes du système climatique. En région tropicale, une hausse de la température, ainsi qu'une intensification des événements de sécheresse et de pluviométrie extrêmes sont à prévoir. C'est dans ce contexte que s'inscrit ce travail, dont le but est d'étudier la réponse de la forêt tropicale à ces changements climatiques prédits en Guyane Française. Pour ce faire, j'ai utilisé les données du dispositif de suivi forestier de Paracou pour construire un modèle de dynamique individuel basé sur les traits fonctionnels des arbres. Un modèle de mortalité a d'abord été réalisé puis couplé à un modèle de croissance.Le modèle couplé ainsi construit permet de modéliser la croissance et la mortalité des arbres sur un pas de temps de 2 ans tout en tenant compte de leur ontogénie et de leurs traits fonctionnels. Ce modèle a d'abord été appliqué aux essences commerciales de Guyane Française en forêt naturelle et exploitée en y ajoutant un indice de stress hydrique. Ceci permet de montrer que le stress hydrique fait baisser la croissance et augmenter la mortalité, tandis que l'exploitation a l'effet inverse. Malgré le signal commun, différentes réponses sont observées selon les espèces. Le modèle a ensuite été appliqué à la communauté en forêt naturelle pour identifier les drivers climatiques et les processus impactés. Il ressort que la croissance est impactée par le stress hydrique et la température, et que la mortalité est impactée par le stress hydrique et la pluviométrie totale.Ces résultats ont enfin permis de construire un modèle complet de dynamique forestière climat dépendant, et de simuler l'évolution d'une communauté pendant un siècle selon différents scénarios correspondant aux prédictions du GIEC. Les simulations mettent en évidence une très forte diminution de la croissance, ainsi qu'une plus faible diminution de la mortalité. Ceci entraine une diminution notable de la surface terrière, du diamètre quadratique et de la biomasse fraiche. Une analyse de sensibilité montre que ces changements sont principalement dus à l'augmentation sévère des températures prédites pour le siècle à venir. Des pistes de réflexion sur les enjeux de modélisation et les échelles considérées sont proposées en discussion de ce travail
In 2013 the intergovernmental panel on climate change (ipcc) publishes its fifth report. This report underlines that an increase of temperature and a strengthening of drought and extreme rainfall are expected in tropical regions. This work was made in this context of climate changes, and aimed to study the response of the rainforest to predicted climate changes. To do this, i used the data from the study site of Paracou French Guiana to build an individual based dynamics model based on the functional traits of trees. This model was first applied to species with a commercial interest in French Guiana, in natural and logged forest and adding a water stress index as predictor. Water stress decreases growth and increases mortality, while logging had the opposite effect. The model was then applied to the community in natural forest for identifying potential climate drivers and impacted processes. Growth is impacted by the water stress and temperature and mortality is imp acted by the water stress and the total rainfall. These results allowed us to build a climate dependent model of forest dynamics and to run simulations of the evolution of a community under different scenarios for the next century. Simulations showed a decrease of growth and a small decrease of mortality. This resulted in a substantial decrease of basal area, squared diameter and fresh biomass
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