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1

Tang, Yong. "Maintenance and Dynamics of Rainforest Edges". Thesis, Griffith University, 2008. http://hdl.handle.net/10072/367442.

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Deforestation and fragmentation of rainforest has become one of the major threats to global biodiversity and the massive loss of rainforest during the past decades has pushed the global biota to the edge of the global species extinction crisis. Despite the increasing public awareness and tremendous efforts made internationally to save the remaining rainforest, the deforestation rate continues to accelerate in many rainforest areas. This trend is due mainly to increasing human population and local or regional economical or political crises creating increased needs and demands on land use and rainforest products. In addition to the loss of large areas of wildlife habitat, a direct consequence of rainforest fragmentation is the increase in the extent of edges, through which “hostile” edge effects can have a profound impact on the dynamics of remaining rainforests. There is an urgent need to understand the underlying mechanisms that drive the dynamics of the rainforest edges and more important, the subsequent long-term impact on the local and regional rainforest. The main objective of the study described in this thesis has been to compare the patterns with which rainforest plants respond to the edge environment at different types of edges involving rainforests. The study was conducted within a fragmented subtropical rainforest complex in Lamington National Park, Southeast Queensland. Rainforest trees, lianas, seedling banks and soil seed banks were investigated at eucalypt forest/ rainforest, pasture/ rainforest and roadside rainforest edges. For each edge type, nine 100 m transects were established from the edge to rainforest interior and transects were extended 50 m into eucalypt forest and pasture for additional sampling of surrounding matrices. Vegetation surveys were conducted along the edge transects for the study of trees, lianas and seedlings. Soil seed banks were investigated by germination experiments conducted in a shade house, using soil samples collected along the edge transect. The results from the edge studies were compared with corresponding studies in a 1 ha rainforest reference plot located in a relatively undisturbed area within the rainforest interior...
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment
Faculty of Environmental Sciences and Engineering
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2

Burns, Shannon. "Rainforest action network green campaign /". Click here to view, 2009. http://digitalcommons.calpoly.edu/artsp/30.

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Thesis (B.F.A.)--California Polytechnic State University, 2009.
Project advisor: Kathryn McCormick. Title from PDF title page; viewed on Jan. 21, 2010. Includes bibliographical references. Also available on microfiche.
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3

Prescott, T. A. K. "Antimicrobial compounds from tropical rainforest plants". Thesis, University of Edinburgh, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.660747.

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Ethnobotanical fieldwork was carried out in New Guinea. An antibacterial field assay kit was developed using freeze-dried strains of S. epidermidis and E. coli which allowed plants used in traditional medicines to be screened in situ without having to take them back to a laboratory. This approach identified Lunasia amara (Blanco) as a candidate species; the use of its bark by tribes of the Whitman Range to treat tropical ulcers, supported by clear zones of inhibition with S. aureus. Samples of the bark were collected for analysis and through activity-guided fractionation, the anti- S. aureus activity of the bark extract was pinned down to a single well resolved HPLC peak (MIC S. aureus NCTC 6571 64μg/ml) which subsequent NMR analysis revealed to be the quinoline alkaloid lunacridine; 2’-O-trifluoroacetyl lunacridine was found to be a more stable derivative however. Lunacridine’s planar cationic structure suggested it might act as a DNA intercalator; 220μM giving 50% binding in an ethidium bromide displacement assay. This in turn suggested DNA topoisomerase II as a likely target for the compound which was confirmed with a kDNA decatenation assay revealing complete inhibition of the enzyme at 5μM. Cell viability assays with MRC-5, H226 and HELA cells showed the compound to be cytotoxic in a time dependent manner producing non-linear dose response curves indicative of a topoisomerase poison mode of action. Activation of the apoptosis pathway enzymes caspase 3/7 was also detected, reaching maximal activity between 24 and 48 hours for the H226 cell line. Thus, lunacridine does not represent a selective antibiotic but with the right structural modifications could be developed as an antineoplastic agent.
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4

Ericsson, Linda-Mari. "Mountain Rainforest Management in Babati District, Tanzania". Thesis, Södertörn University College, School of Life Sciences, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-634.

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This paper deals with Community Based Forest Management in Mountain rainforests in Babati. This form of management is when the Communities are managing the forest with some help from the Government.

I have made a field study to see how the managing is working the mountain forests. I made interviews with chairmen, guards and district council. The purpose with the interview is to give answers to my questions about CBFM and how it is working. I want to see if the CBFM is sustainable in Babati and know if the villagers are satisfied with it. To answer the sustainability questions, studies in Ostroms eight principles for sustainable forest management is made.

The main conclusions of the study are: Babati will have a sustainable management if they follow the rules and laws that are made for Community Based Forest Management, if the community gets some kind of benefits for being the manager and they want to take care of the forest in a good way when they are the owners. If there are threats against the villagers like pressure from others villages or corruptions this sustainability can be destroyed.

CBFM needs supporting systems, help from the Government, clearly defined boundaries and the basic needs like food and shelter is fulfilled before they can think of the ecosystem health and sustainability.

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5

Healey, John Robert. "Regeneration in a Jamaican montane tropical rainforest". Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335160.

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6

Lucey, Jennifer Marie. "Insect diversity across rainforest-oil palm ecotones". Thesis, University of York, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.547326.

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7

Skoglund, Björn. "Diffusive gas fluxes in neotropical rainforest streams". Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-105692.

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Rainforests are of great importance to global carbon cycling, but the importance of deforestation and change in land use is poorly understood due to a lack of studies quantifying the difference in carbon fluxes between original rainforest and agricultural land. Furthermore, the aquatic outgassing of neotropical systems have been proven to have greater impact on global carbon cycling than previously anticipated (Richey et al 2002).In this study we investigated the aquatic concentration and daily diffusive gas flux of CO2 and CH4 from 4 pristine sites and 4 impacted sites, respectively, in 4 streams running along a gradient of anthropological impaction in the Atlantic Rainforest, Brazil. Statistically significant differences between pristine and impacted sites were found in all streams for both CO2 and CH4. On average, the impacted sites were found to be emitting almost three times as much C into the atmosphere as the pristine sites, mainly owing to CO2 emissions (14172±5226 mg C m-2 d-1). Exploring an area of the neotropical carbon cycle that is not yet fully understood, the study draws attention to the significant difference in aquatic outgassing from rivers observed at different impaction levels and highlights the need for further field studies.
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8

Hou, Yanpeng. "Antiproliferative Natural Products from the Madagascar Rainforest". Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/39467.

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As part of an International Cooperative Biodiversity Groups (ICBG) program and a continuing search for anticancer natural products from the Madagascar rainforest, twenty extracts from Madagascar were selected for investigation based on their antiproliferative activity. Bioassay-guided fractionation of five of the extracts yielded sixteen new compounds, and their structures were determined using a combination of 1D and 2D NMR experiments, including COSY, HSQC/HMQC, HMBC, and ROESY/NOESY sequences, mass spectrometry, and chemical conversion. In addition, ten known compounds were obtained from five of the extracts. Studies on the remaining extracts were suspended due to various reasons. A multi-step synthesis of the sesquiterpenoid, (7R*)-opposite-4(15)-ene-1beta,7-diol, was also described. The first chapter of this dissertation reviews the new compounds isolated from Malagasy plants and marine organism in the last two decades. Chapters II to VI discuss the isolation, structure elucidation and bioactivities of new compounds from Scutia myrtina, Cordyla madagascariensis ssp. madagascariensis, Elaeodendron alluaudianum, Cassipourea lanceolata, and Sclerocarya birrea subsp. caffra. Chapter VII describes the synthesis and bioactivity of the sesquiterpenoid,(7R*)-opposite-4(15)-ene-1beta,7-diol. The isolation of known compounds is discussed briefly in the last chapter.
Ph. D.
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9

Robinson, Niall Hamilton. "Aerosols in and above the Bornean rainforest". Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/aerosols-in-and-above-the-bornean-rainforest(0418d0eb-4a42-41d0-97ab-555cbb803c1e).html.

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Atmospheric aerosols affect climate directly by scattering and absorbing solar radiation, and indirectly by affecting the albedo and lifetime of clouds through their role as cloud condensation nuclei. Aerosol sources, and the processes that govern their evolution in the atmosphere are not well understood, making the aerosol effects a significant source of uncertainty in future climate predictions. The tropics experience a large solar flux meaning that any radiative forcing in this region is particularly important. Despite this, there is a paucity of data from the tropics, with the majority of previous studies performed in the northern mid-latitudes. The few in-situ studies of aerosol composition that have been performed are all in the continental settings of Amazonia or Africa. Until now the 'maritime continent' region of South East Asia has remained unstudied. Presented here are Aerosol Mass Spectrometer composition measurements from the Oxidant and Particulate Processes Above a South East Asian Rainforest project, performed from ground and airborne measurement platforms in and around the rainforest of Borneo, South-East Asia. Unlike the previous tropical studies, this allows for the characterisation of a region of mixed terrestrial and marine biogenic emissions. The region is also undergoing rapid land use change, with forest being converted for agriculture, particularly the cultivation of oil palms. This study also allows for the characterisation of a region that is beginning to undergo land use change, providing insight into emissions from different land use types, and providing a benchmark to measure the effects of land use change against in the future.Total sub-micron aerosol loadings were found to be lower than studies in the northern mid-latitudes, similar to previous tropical studies. However, aerosol composition was different to that observed in Amazonia, with much greater sulphate loadings in Borneo. A regional background of sulphate and highly oxidised organic aerosol was identified, with organic aerosol that is less oxidised originating inland. Aerosol confined to a shallow marine boundary layer upwind of Borneo is lofted higher into the troposphere as it advects across the island, with regional aerosol being removed and biogenic terrestrial aerosol added. The lofting of this aerosol is expected to extend its atmospheric lifetime and change its role in the Earth's radiative budget. A novel organic aerosol signal was identified which correlated with gas phase isoprene oxidation products, strongly suggesting that it was significant of isoprene SOA. Aerosol associated with this signal made up a substantial fraction of the organic aerosol loading. This opens up the opportunity for future studies to make isoprene SOA measurements using the Aerosol Mass Spectrometer in other studies. A substantial amount of the organic aerosol in Borneo was attributed to isoprene oxidation.
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10

Kroc, Jonathan Fleming. "Tucson's Rainforest: Data Processing for Tracing Carbon in Soil, Plants, and Atmosphere in the Tropical Rainforest of Biosphere 2". Thesis, The University of Arizona, 2014. http://hdl.handle.net/10150/323455.

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11

Lemky, Kim M. K. "The Amazon rainforest ecotourism industry of Napo, Ecuador". Thesis, University of Ottawa (Canada), 1992. http://hdl.handle.net/10393/7716.

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The two types of ecotourists have different impacts on both the local economy and the environment. The resort ecotourists are isolated to resorts. Each night is spent in the same place and tours consist of day hikes to local Indian villages and to the primary rainforest. These tourists aid the economy less than budget ecotourists because the employees that serve them are hired from outside the region and food goods for the tourists are imported into the region. In contrast, the budget ecotourists are spatially dispersed and travel each night to a new tourist camp. The budget ecotourists are essential to the economy of Pto. Misahualli. Only inhabitants of Pto. Misahualli are employed in the ecotourism industry, and all food for jungle trips is bought at local stores. Although the budget ecotourists are much more important for the local economy than resort tourists, the infrastructure of the resort ecotourists has a place in promoting the rainforest at the international level. The current ecotourism industry in Napo is sustainable within its own parameters, but the infringement of the oil industry and the small farm colonization on the primary rainforest will ultimately lead to its downfall. (Abstract shortened by UMI.)
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12

Burn, Michael James. "Palynological characterisation of Amazonian rainforest communities, northeast Bolivia". Thesis, University of Edinburgh, 2008. http://hdl.handle.net/1842/29481.

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Descriptive and morphometric methods are used to identify and differentiate key pollen types of the Moraceae family (Brosimum, Helicostylis, Pseudolmedia, Sorocea and Pourouma) that are well represented in Amazonian rainforest communities of Noel Kempff Mercado National Park (NKMNP). Using multivariate and cluster analyses applied to modern-pollen and floral-biometric data obtained from study plots situated within rainforest communities of the park, it is demonstrated that terra firme (well-drained) evergreen, terra firme liana, seasonally inundated, and riparian rainforests are readily characterised by their pollen rain. Analogue matching techniques are employed to numerically compare the resulting signatures with core-top pollen assemblages taken from the Quaternary sedimentary record of two lakes within the park, and of three others situated in the floristically distinct Llanos de Moxos ecoregion. Such comparisons demonstrate that riparian forest communities represent the closest modern analogue for pollen assemblages obtained from surface sediment samples from lakes with NKMNP; however, elements of terra firme forests also constitute a significant proportion of these assemblages. There is a clear separation of pollen trap and surface sediment spectra obtained from NKMNP from those obtained from outside the park reflecting floristic differences between rainforests of the Madeira-Tapajós ecoregion and gallery forests of the Llanos de Moxos ecoregion. These results not only provide the potential for much more detailed and reliable Neotropical palaeovegetation reconstructions but also enable a more precise estimation of past carbon storage from Amazonian fossil pollen records.
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13

Raheem, Dinarzarde Chirantenne. "Land-snail diversity in Sri Lankan rainforest fragments". Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.613834.

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14

Marsh, Charles John. "Spatial turnover of insect communities at rainforest edges". Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/11100.

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Rainforest fragmentation is leading to huge increases in the quantity of forest in close proximity to edges. Edge effects may cause multiple alterations to ecological processes, however we do not know their impacts on the spatial turnover of communities, β-diversity. Using a dung beetle community in the north-east Brazilian Amazon, I addressed the problem in four, systematic steps. First, as β-diversity is spatially dependent it is essential to sample at small through to broad scales, presenting us with a limitation of sampling over large areas at fine scales. I present a scalable sampling design based upon a fractal series of equilateral triangles that proved in simulations to be more efficient at recovering accurate estimates of β-diversity than classical sampling designs. Second, I investigated optimal bait choice for accurately sampling the dung beetle community. A human-pig dung mix was found to be as effective as pure human dung baits, whilst removing possible dung source limitations. Third, I investigated the drivers of β-diversity based upon traits that govern foraging strategies. Wing and body morphology was found to be a significant predictor of the spatial scales at which species populations were structured. I then partitioned the variation attributed to environment and space for each morphological subset at three spatial scales. The drivers, and the scales at which they were most important, were dependent upon morphological traits, which further interacted with habitat modification. Finally, I investigated if β-diversity was greater in dung beetles at the forest edge. Linearising the fractal design, I estimated turnover within communities at set distances from the edge. Results were mixed: there was no elevation at a primary-Eucalyptus forest edge, but significantly higher turnover within communities at a primary-secondary forest edge than interior communities. This work increases our knowledge of how fragmentation and edge effects impact the underlying processes governing diversity.
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15

Cunningham, Michael. "Vicariance, speciation and diversity in Australopapuan rainforest frogs /". [St. Lucia, Qld.], 2001. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16280.pdf.

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16

Jensen, Mari N. "Amazon Rainforest Greens Up in the Dry Season". College of Agriculture, University of Arizona (Tucson, AZ), 2006. http://hdl.handle.net/10150/295884.

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17

Eaton, Sally. "Achieving landscape-scale conservation for Scotland's rainforest epiphytes". Thesis, University of Glasgow, 2018. http://theses.gla.ac.uk/8854/.

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Within the UK, the continuing biodiversity crisis has led to a policy driven shift in the conservation sector; moving away from localized site scale conservation to a landscape-scale. This approach encourages fragmented habitat patches to be integrated into a much larger habitat network. Epiphytic lichens provide an ideal model system for studying the effectiveness of conservation initiatives within fragmented habitats, due to their metapopulation structures whereby individual trees within woodlands (and woodland stands within wooded landscapes), represent isolated habitat patches. Old-growth woodland in particular provides suitable habitat to a suite of lichens known as the Lobarion community, which are declining throughout Europe. Regeneration within these old growth areas, though essential for future habitat persistence, causes shading and ultimately leads to local extinctions of shade intolerant lichen epiphytes. A landscape scale conservation strategy that relies on habitat permeability to balance colonisation of post-regeneration woodland patches with extinctions in ageing woodland patches elsewhere in the landscape has been proposed as a management strategy to meet the needs of both lichen epiphytes and their woodland habitat. The unique conditions found in western Scotland, combining a relative abundance of high quality old growth habitat (in a European context) coupled with robust populations of some members of the Lobarion community, could provide an ideal opportunity to test such a management strategy. In this thesis, the plausibility of landscape-scale conservation as a management strategy for epiphytic lichens is explored, using a suite of nine target epiphytes of contrasting ecological traits set within Glen Creran, a temperate rainforest on the west coast of Scotland: 1. The habitat requirements of nine target epiphytes were identified and predictions of species distribution made over an entire glen using a species distribution modelling (SDM) approach. The SDM’s were found to apply more generally within the wider biogeographic area for five of the nine species, providing an evidence base for future conservation plans in Scotland’s rainforest zone. 2. A novel method to determine dispersal distance in lichen epiphytes was developed, combining a mechanized propagule trap with molecular techniques. This methodological advance allowed the first direct comparative study of lichen epiphytes in a natural context. 3. An agent based model was developed combining the results of 1. and 2. above to investigate the effect of habitat connectivity on colonisation in six contrasting lichen epiphytes, enabling inferences of species response to landscape-scale conservation scenarios within the study system to be made.
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18

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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19

Cozza, John. "Sex Expression in a Rainforest Understory Herb, Begonia urophylla". Scholarly Repository, 2008. http://scholarlyrepository.miami.edu/oa_dissertations/186.

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Monoecy, the production of distinct male and female flowers on the same plant, is an important, though little studied, sexual strategy in the rainforest understory. This study of a monoecious plant discovered a cue to induce flowering, explored the interplay of gender constraint vs. plasticity in a natural population, and tested possible causes of gender in two laboratory experiments. An experiment in the lab found that reduced photoperiod for three weeks is an unambiguous cue for flowering. The remarkably long inductive period is followed by a long and variable period of floral initiation. This results in only partial synchronization of flowering among plants in a patch, which enhances mating opportunities in this protandrous plant. Inflorescence architecture is highly constrained, and ideally produces a phenotypic gender (proportion female) of about 0.5. However, in the forest at Las Cruces, Costa Rica, most plants were less female than predicted, mostly through abortion of female buds. Plants showed gender plasticity between and within years. Large plants produced more flowers and were more female in gender, and less variable in gender, than small plants. Reproduction was poorly correlated with environmental resource availability, measured as canopy openness, soil moisture, pH, and soil phosphorus, ammonium and nitrate. Phenotypic selection analysis on seed production suggests an optimal gender of 50-60% female, yet plasticity to be less female than this optimum, and in particular to express only male function, has been maintained. In a factorial experiment in the lab, high light or high nitrogen caused plants to produce more flowers and to be proportionally more female, and larger in weight, than low light or nitrogen. The effects of light and nitrogen on reproduction, plant size, and leaf greenness suggest an energy based determination of gender. Gender may be mostly influenced by plant size, but sometimes also opportunistically by environment. Inoculation with mycorrhizas caused plants to be less female in gender, and smaller in weight, than plants that were not inoculated. This suggests a net cost of mycorrhizas under experimental conditions, and supports the emerging view of the mycorrhizal symbiosis as not necessarily mutualistic under all circumstances.
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20

Labor, Felicia. "Deforestation patterns and hummingbird diversity in the Amazon rainforest". Thesis, Stockholms universitet, Institutionen för naturgeografi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-140513.

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In recent decades expanding land-use change has caused extensive deforestation of the tropical rainforestinducing large-scale transformation of the landscape patterns across the South American continent. Landscapechange is a modification process of the natural forest cover into fragments which generate various ecologicalimpacts. Habitat loss is identified to be a major threat to biodiversity, as it exposes species to the risk ofextinction. This study investigates 80 locations within tropical rainforest biomes to examine the landscape changewhich has occurred from 1993 – 2014. The intention is to identify the impacts of landscape fragmentation onhummingbird species diversity by spatial landscape analysis in GIS and regression modeling. The analysis foundthat there is no relationship between deforestation and reduction of hummingbird diversity. The results indicatethat hummingbird species are not particularly sensitive to landscape change as they have high resilience in regardto forest fragmentation. A potential threshold value of deforestation degree could be identified, up to whichhummingbird species richness increased, but locations subjected to over 40% fragmentation were estimated tohave lower hummingbird diversity. However, by using the spatial explicit biological data, the analysis indicatethat an extinction debt may exist in the landscape, and that future extinctions may be expected to occur in thefollowing decades as consequence of deforestation. Other factors may be as important determining variables forspecies richness: the spatial scale of the study, the habitat connectivity, hummingbird generalist tendencies.Conclusively, identification of the key factors of deforestation impacts on species diversity is essential for futureefficiency in conservation planning and sustainability of the tropical rainforest biodiversity.
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21

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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Berry, Nicholas J. "Impacts of selective logging on biodiversity in Bornean rainforest". Thesis, University of Leeds, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.496551.

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Malhado, Ana Claudia Mendes. "The Functional Biogeography of Leaves of the Amazonian Rainforest". Thesis, University of Oxford, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.504111.

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Massignan, Rinaldi Gouveia Francine. "The representation of the Amazonian Rainforest in British Newspapers". Thesis, Malmö universitet, Fakulteten för kultur och samhälle (KS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-24029.

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This paper analyses the representation of the Amazonian rainforest as reported by British newspapers in August 2019. Through a combination ofFairclough's Critical Discourse Analysis Approach and the news values theory of Galtung and Ruge, The CDA analysis examined the discourse as a text, as a discourse practice and as a social practice. The second theory of Galtung and Ruge used in this study identified newsworthy values in the articles from the different newspapers. The results have showed that the Amazonian rainforest is perceived as being an important resource worldwide, while it evokes concern in climate change and in the increase of deforestation. Further, the results based on the theory of news values showed how the greater distance of a nation from the topic leads to greater attention given to elite people or negative events.
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25

Bito, Darren. "Structure and Dynamics of Herbivore Assemblages Along an Altitudinal Gradient: Indicators of Climate Change". Thesis, Griffith University, 2011. http://hdl.handle.net/10072/366400.

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Herbivory is one of the major ecosystem processes, as are pollination and seed dispersal, which drives ecological changes in both the phytophagous fauna and their host plant assemblages. The amount of herbivory damage on a host species represents not only the amount of herbivory pressure due to phytophagous insects but also the predatory pressure due to predators at higher trophic levels. Furthermore, additional interactions of climate and environmental factors determine the conditions of the host species and subsequently the assemblage of herbivorous insects that colonize them. All these direct and indirect, positive and negative influence of climate and environmental factors combined with the requirement to propagate themselves cascades to through the higher trophic levels down to assemblage of herbivorous insects and their host species at the lower trophic levels. This study considered the host specificity of caterpillars, herbivory pressure and herbivory damage on trees and shrubs along an altitudinal gradient within subtropical and temperate rainforest. The work has attempted to show how a selected ecological process (herbivory) is being influenced by various factors including altitude, ant predation pressure and host plant species, canopy strata and physical properties of leaves.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Arts, Education and Law
Science, Environment, Engineering and Technology
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26

Stockdale, Mary Caitrin. "Inventory methods and ecological studies relevant to the management of wild populations of rattans". Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240446.

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Leite, Edson Junqueira. "Forest genetic conservation in Brazil : a review of priority taxa for the 'Cerrado'". Thesis, Bangor University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385734.

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28

Dalling, James William. "Regeneration on landslides in the Blue Mountains, Jamaica". Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240015.

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29

Odell, Erica. "Lianas, trees and insect herbivory". Thesis, Griffith University, 2018. http://hdl.handle.net/10072/380989.

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Insect herbivory is a key ecological process which mediates the structure, functioning and maintenance of forests. Studies of insect herbivory in tropical forests typically focus on trees whereas the contributions of other plant types, particularly climbing plants, remains undervalued and under studied. Lianas, or woody climbing plants, are important ecosystem contributors. Per unit basal area, lianas support substantially more leaves than trees and typically comprise 20-40% of the above ground leaf biomass in rainforests. This indicates a likely function in insect herbivory. Little data, however, exists which quantifies the importance of their contribution to overall ecosystem dynamics, particularly in contrast with trees. Information on the contributions of other plant types to herbivory are necessary if we are to fully appreciate the role of lianas in herbivory and understand the ways in which forests and associated processes may shift given anticipated environmental and vegetation changes. This thesis aims to address this knowledge gap and demonstrate the value of lianas in supporting herbivory and associated insect assemblages. I aim to establish the need for a better understanding of liana-supported insect herbivory, quantify the trophic link among different plant types and insects in two contrasting rainforests, and determined the influence of structural and chemical leaf traits. First, I determine the need for liana focussed herbivory research by providing a comprehensive review of the literature. Second, I examine the temporal changes in liana and tree communities over two decades in a 1 ha plot of Australian subtropical rainforest. It is firmly established that lianas are increasing in Neotropical rainforest. In other bioregions, however, the pattern is less clear and derived from few sources. In Australia, where the factors influencing vegetation dynamics may differ, no such studies exist. I found liana abundance and biomass increased substantially from 2005 to 2015 while tree abundance remained stable from 1995 to 2015. Tree biomass also rose considerably, but at approximately half the rate of lianas. Based on the structure of liana and tree communities, I suggest increasing atmospheric CO2 to be the most probable explanatory hypothesis over changes in rainfall or tree mortality. Given the results presented here and other documented increases in liana abundances globally, it is concerning we do not know more about the ecosystem services they provide. Third, theoretical and empirical evidence suggests lianas may be an important food source for phytophagous insects. I address this hypothesis by two methods. First, in a literature-based study I assess the relative use of lianas as host plants for Australian butterflies. Second I make quantitative assessments Insect herbivory is a key ecological process which mediates the structure, functioning and maintenance of forests. Studies of insect herbivory in tropical forests typically focus on trees whereas the contributions of other plant types, particularly climbing plants, remains undervalued and under studied. Lianas, or woody climbing plants, are important ecosystem contributors. Per unit basal area, lianas support substantially more leaves than trees and typically comprise 20-40% of the above ground leaf biomass in rainforests. This indicates a likely function in insect herbivory. Little data, however, exists which quantifies the importance of their contribution to overall ecosystem dynamics, particularly in contrast with trees. Information on the contributions of other plant types to herbivory are necessary if we are to fully appreciate the role of lianas in herbivory and understand the ways in which forests and associated processes may shift given anticipated environmental and vegetation changes. This thesis aims to address this knowledge gap and demonstrate the value of lianas in supporting herbivory and associated insect assemblages. I aim to establish the need for a better understanding of liana-supported insect herbivory, quantify the trophic link among different plant types and insects in two contrasting rainforests, and determined the influence of structural and chemical leaf traits. First, I determine the need for liana focussed herbivory research by providing a comprehensive review of the literature. Second, I examine the temporal changes in liana and tree communities over two decades in a 1 ha plot of Australian subtropical rainforest. It is firmly established that lianas are increasing in Neotropical rainforest. In other bioregions, however, the pattern is less clear and derived from few sources. In Australia, where the factors influencing vegetation dynamics may differ, no such studies exist. I found liana abundance and biomass increased substantially from 2005 to 2015 while tree abundance remained stable from 1995 to 2015. Tree biomass also rose considerably, but at approximately half the rate of lianas. Based on the structure of liana and tree communities, I suggest increasing atmospheric CO2 to be the most probable explanatory hypothesis over changes in rainfall or tree mortality. Given the results presented here and other documented increases in liana abundances globally, it is concerning we do not know more about the ecosystem services they provide. Third, theoretical and empirical evidence suggests lianas may be an important food source for phytophagous insects. I address this hypothesis by two methods. First, in a literature-based study I assess the relative use of lianas as host plants for Australian butterflies. Second I make quantitative assessments Insect herbivory is a key ecological process which mediates the structure, functioning and maintenance of forests. Studies of insect herbivory in tropical forests typically focus on trees whereas the contributions of other plant types, particularly climbing plants, remains undervalued and under studied. Lianas, or woody climbing plants, are important ecosystem contributors. Per unit basal area, lianas support substantially more leaves than trees and typically comprise 20-40% of the above ground leaf biomass in rainforests. This indicates a likely function in insect herbivory. Little data, however, exists which quantifies the importance of their contribution to overall ecosystem dynamics, particularly in contrast with trees. Information on the contributions of other plant types to herbivory are necessary if we are to fully appreciate the role of lianas in herbivory and understand the ways in which forests and associated processes may shift given anticipated environmental and vegetation changes. This thesis aims to address this knowledge gap and demonstrate the value of lianas in supporting herbivory and associated insect assemblages. I aim to establish the need for a better understanding of liana-supported insect herbivory, quantify the trophic link among different plant types and insects in two contrasting rainforests, and determined the influence of structural and chemical leaf traits. First, I determine the need for liana focussed herbivory research by providing a comprehensive review of the literature. Second, I examine the temporal changes in liana and tree communities over two decades in a 1 ha plot of Australian subtropical rainforest. It is firmly established that lianas are increasing in Neotropical rainforest. In other bioregions, however, the pattern is less clear and derived from few sources. In Australia, where the factors influencing vegetation dynamics may differ, no such studies exist. I found liana abundance and biomass increased substantially from 2005 to 2015 while tree abundance remained stable from 1995 to 2015. Tree biomass also rose considerably, but at approximately half the rate of lianas. Based on the structure of liana and tree communities, I suggest increasing atmospheric CO2 to be the most probable explanatory hypothesis over changes in rainfall or tree mortality. Given the results presented here and other documented increases in liana abundances globally, it is concerning we do not know more about the ecosystem services they provide. Third, theoretical and empirical evidence suggests lianas may be an important food source for phytophagous insects. I address this hypothesis by two methods. First, in a literature-based study I assess the relative use of lianas as host plants for Australian butterflies. Second I make quantitative assessments of herbivore damage in the canopy of a tropical Chinese rainforest and the understory of a subtropical Australian rainforest based on new, primary data. Lianas, and vines alike, are hypothesised to be important food plants for butterflies. This speculation, however, has never been formally tested. Based on available food plant information of Australian butterflies, I found lianas to be an important food source for butterfly caterpillars in rainforests and their use as host plants to be greater than what simple plant diversity would predict. Interestingly, butterflies feeding on climbing plants had significantly greater incidences of monophagy than those feeding on trees. The patterns of host plant use and specialisation on trees and lianas are similar to those found in phytophagous rainforest beetles elsewhere. If lianas support greater diversity and abundances of foliar feeding insects than trees, we would expect this to be reflected by asymmetrical incidences of herbivore damage across the two plant types. I found no overall significant difference across plant types in neither the canopy of a tropical Chinese rainforest or the understory of a subtropical Australian rainforest, providing further support for this hypothesis. I did however observe that; 1) lianas influence their host’s leaf traits, most likely through inputs of nitrogen rich leaf litter around the base of their hosts, 2) under drought conditions lianas may reduce the amount of herbivory occurring on their host trees, and 3) leaf traits important for predicting herbivory are not consistent across plant types. Through the combination of studies, I have shown that lianas are an important food source for herbivorous insects at least as much so as trees. The results of this thesis have helped close the knowledge gap in our understanding of herbivory and demonstrate the importance of lianas in supporting insect assemblages. Without understanding the contributions of other plant types to herbivory (and the associated insect faunas they support) we are unable to make accurate models and predictions about their future. Given lianas are increasing in many tropical rainforests, including those studied here, it is concerning that not more is known about their contributions to herbivory and their relationships with the insect herbivores they support – this thesis goes part way to allay this concern.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Sc
Science, Environment, Engineering and Technology
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30

Fernandez, Maria y Sebastian José Caballero. "The grieving forest; the social-environmental degradation in Amazonian Rainforest". Thesis, Mälardalen University, School of Sustainable Development of Society and Technology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-739.

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The Amazonia is the biggest rainforest in the world, home also to probably the largest amount of different bio diversity species in our planet. Notwithstanding these incredible attributes, it is also one of the most threatened regions earth that extends to the whole planet. This thesis analyzes just a small segment of the interrelation of different human actors reacting to environmental problems. Theoretical frame works of different nature are used in this thesis in an effort to combine with synergy the strengths and potential benefits of political ecology, the stakeholder model, local institutionalisms, and the political and economical role of persons just to mention the most significant. This combination of these different scientific and empirical disciplines offers us a chance to apply the full potential for the analysis of the environmental problems related to human actions in the regional settings with the capability of gaining in depth knowledge that can be applied later in the design and implementation of potential alternatives seeking s the welfare of all human and biological stakeholders as our knowledge allows us currently. The thesis is structured on three study cases that cover a vast area of the Amazonia: the first case is located in Bolivia where we analyze the situation of Santa Maria de Maravilla, regarding the problems of land property and land use; the second case is located in Brazil in the Santarém region, where an important intensive production of soybean is affecting the environment as well as confronting the local communities; the third case is located in Ecuador analyzing the situation of the Block 15 region; an area deeply affected by the petroleum companies and the generic concepts of investment in extractive industries as a tool for regional and national development.

Local actors are of the highest importance despite the different nature of the case studies, in order find commonalities which might allow us to make hypothetical counteracting models to decrease the devastating of environmental degradation in the Amazonia; some of the external actors (like the NGOs) can play an influential role in order to improve the collaboration and trust with local members.

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31

Hocknull, Scott Alexander Biological Earth &amp Environmental Sciences Faculty of Science UNSW. "Late Cainozoic rainforest vertebrates from Australopapua: evolution, biogeography and extinction". Awarded by:University of New South Wales. Biological, Earth & Environmental Sciences, 2009. http://handle.unsw.edu.au/1959.4/44580.

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Understanding the evolution, biogeography and extinction of Australopapuan vertebrate lineages is fundamental to determining baseline responses of those groups to past environmental change. In light of predicted climatic change and anthropogenic impact, it is imperative to determine the trajectories of Australia???s modern flora and fauna. In particular, mesothermic rainforest faunas are among Australia???s most vulnerable terrestrial biota under threat from both natural and anthropogenic causes. There is a gap in knowledge of past patterns of change and, in particular, a conspicuous lack of direct evidence of response of rainforest faunas to past climatic change. This study documents the late Cainozoic Australopapuan rainforest vertebrate record and its response to environmental change via adaptive radiation, biogeographical change and extinction. In particular, it provides the first detailed systematic appraisal of Quaternary fossil sites and local faunas from northern Australia. The study documents the only known Quaternary mesothermic rainforest fauna in Australia and its transition to a xeric-adapted fauna during the middle Pleistocene. The fossil assemblages analysed are comprised of dozens of species, including several new genera and species. Each fossil taxon shares a close phylogenetic relationship with others either known only from the Australian Tertiary record or from Quaternary-Recent New Guinea and Wet Tropics rainforests. The presence of many species is evidence of previously much larger distributions followed by subsequent massive range retractions. Detailed documentation of this rare fauna testifies to rainforest stability in central eastern Queensland until approximately 280,000 years ago, when the development of an El Nino dominated climate generated variable climatic patterns that could not support aeseasonal rainforest. Extinction of this late Pleistocene rainforest fauna serves as one of only two examples of major rainforest faunal turnover in Cainozoic Australia, the other occurring in the late Miocene. These two major extinction events are compared. The late Pleistocene faunal extinction differs from the late Miocene event in being biased towards large-bodied, terrestrial herbivores and carnivores (both reptile and mammal). This study also combines fossil and phylogenetic data with latest understanding of palaeogeography, tectonics and sea level history along Australia???s northern margin to provide hypotheses of faunal dispersal between New Guinea and mainland Australia throughout the Neogene.
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32

Cansari, Rogelio. "Cultivation of wild palms in the rainforest of Darién, Panamá". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ50731.pdf.

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33

Thomas, Raquel Simone. "Productivity and resource availability in lowland tropical rainforest in Guyana". Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404769.

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34

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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35

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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36

Cudjoe, Anthony Richmond. "Biocontrol of cassava mealybugs in the rainforest zone of Ghana". Thesis, Imperial College London, 1990. http://hdl.handle.net/10044/1/47832.

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37

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.
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38

Leveridge, Max Carter. "Evaluating attitudes towards large carnivores within the Great Bear Rainforest". Miami University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=miami1556726212319148.

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39

Gilman, Alex Caroline. "Biodiversity patterns in tropical montane rainforest flora of Costa Rica". Diss., Restricted to subscribing institutions, 2007. http://proquest.umi.com/pqdweb?did=1472126481&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.

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40

Parracho, Luciane Ceolato. "The representation of the brazilian rainforest in recent mainstream films". Florianópolis, SC, 2003. http://repositorio.ufsc.br/xmlui/handle/123456789/86303.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão. Programa de Pós-Graduação em Letras/Inglês e Literatura Correspondente.
Made available in DSpace on 2012-10-21T05:37:52Z (GMT). No. of bitstreams: 0
Este estudo tem por objetivo analisar a maneira pela qual a floresta Amazônica é representada nos filmes Medicine Man (1992) dirigido por John McTiernan, e At Play in the Fields of the Lord (1991) dirigido por Hector Babenco. Através da análise de elementos como enredo, ponto de vista, e a construção do espaço da narrativa, foi possível identificar a relação entre os protagonistas e a floresta e também entre o enredo e a floresta; o tipo de espaço construído; e como a voz dos Índios é apresentada. A comparação entre os dois filmes revelou que ambos retratam a floresta Amazônica como um espaço politicamente aberto, onde qualquer entidade pode desenvolver pesquisa e que os personagens americanos são apresentados como heróis que tentam ajudar os índios.
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41

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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42

Nakamura, Akihiro. "Development of Soil and Litter Arthropod Assemblages in Rainforest Restoration". Thesis, Griffith University, 2008. http://hdl.handle.net/10072/367553.

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Broadscale forest clearance is a major human-induced disturbance with devastating consequences for biodiversity. With a rise in public awareness of biodiversity, the last few decades have seen an increasing number of reforestation activities aimed at recreating natural habitat. To date, research on the outcomes of reforestation for biodiversity have mostly focused upon the recovery of vegetation structure and composition, with relatively little attention being paid to the recovery of fauna, especially invertebrates. Arthropods inhabiting soil and leaf litter constitute a considerable proportion of the biomass and diversity of a given faunal community, and exhibit strong associations with ecological functioning (i.e. soil formation, decomposition). The recovery of soil and litter arthropods in restored landscapes is therefore important, not only for the recovery of biodiversity but also for the re-development of a functioning ecosystem, a goal of most types of reforestation programs. However, we know little about the patterns of development of arthropod assemblages in reforested landscapes or the mechanisms underpinning any such patterns. The broad objective of this study was to investigate the effects of selected factors on the colonisation patterns of restored rainforest patches by soil and leaf litter arthropods. Criteria for selecting factors for study included their potential influence on the development of arthropod assemblages and their potential for manipulation by restoration practitioners. The study was conducted on the Blackall Range near Maleny, a mid-elevation (250-530 m a.s.l.) basaltic plateau in subtropical eastern Australia (26°S, 152°E). The plateau supported subtropical rainforest until European settlement in the 19th century, when most of the rainforest was cleared for pasture. The factors selected for study, in relation to the colonisation of restored habitat patches by soil and litter arthropods, were as follows: 1. the isolation of restored habitat patches from remnant forest; 2. the efficacy of inoculation (re-introduction of rainforest soil and litter arthropods) to restored habitat patches; 3. the quality and quantity of substrate (i.e. mulch) used during the initial stages of rainforest restoration; 4. the degree of shading and depth of substrate, and their interaction; and, 5. the short- and longer-term impacts of glyphosate herbicide on arthropod assemblages. To test explicitly the effects of these factors on arthropod colonisation of restored habitat patches, an experimental approach was adopted in this study. The first four factors were addressed by means of a manipulative field experiment. Small-scale habitat patches were created by adding sterilised mulch to an area previously treated with glyphosate herbicide, and covered with shadecloth, to simulate various conditions of forest restoration which may be experienced by colonising arthropods. In order to test for the impacts of a glyphosate herbicide on rainforest arthropods, I carried out a separate field experiment in which experimental patches were established within remnant rainforests. The experimental approach adopted in this study allowed for the construction of replicated units, while controlling for extraneous factors (e.g. heterogeneity of litter composition, habitat area, age of restoration), to enable robust examination of the effects of selected factors. To monitor assemblage composition, arthropods were collected using two methods: pitfall traps and extraction from litter. Responses of arthropods were analysed at two main levels of taxonomic resolution: ‘coarse’ arthropods (all arthropods sorted to Order/Class) and ants, identified to species. Before the field experiments, a survey was carried out to collect reference information on the distribution of soil and litter arthropods in remnant rainforests (undisturbed reference sites) and cleared pasture (disturbed reference sites) in the study region. Regardless of the sampling method (pitfall or litter extraction) or taxonomic resolution employed (coarse arthropods or ant species), the composition of arthropod assemblages clearly differed between rainforest and pasture. The information obtained from this survey generated potential bio-indicators of forested and cleared habitats, assisting interpretation of the data obtained from the field experiments. The effects of habitat isolation and inoculation were tested using ‘restored’ habitat patches which were established within cleared pasture at increasing distances (0, 15, 100 and ca. 400 m) from the edges of rainforest remnants. After nine months, rainforest-dependent taxa were found to have only colonised the habitat patches closely adjacent to rainforest remnants. Attempts to increase the extent of arthropod establishment by inoculation were unsuccessful: the majority of rainforest arthropods from the raw inoculum failed to persist within the isolated plots. The results indicated that many forest-dependent soil and litter arthropods may have a limited capacity to colonise isolated restoration sites, and/ or small experimental plots in the short term. Inference from the experiment was potentially limited by the relatively small temporal and spatial scales of restoration treatments. Avoiding these limitations in future research may require controlled and replicated efforts in experimental restoration over larger areas, based on collaborations between researchers and practitioners. To test the effects of quality and quantity of substrate on arthropod colonisation, habitat patches were established by adding either sterilised hay (a conventionally used mulching material in restoration projects) or woodchip mulch (a structurally more complex alternative), each at two depths (3-5 cm, 10-15 cm). Habitat patches were positioned within pasture adjacent to the edges of rainforest remnants to minimise the effect of isolation, and were all unshaded to create conditions similar to those during the initial stages of rainforest restoration. Despite its simple composition, hay performed better than woodchips in facilitating colonisation by arthropods characteristic of rainforest. However, neither hay nor woodchip mulch inhibited arthropods invading from the surrounding pasture. Shallow hay was favoured by ants characteristic of rainforest, but other groups of arthropods (e.g. Coleoptera, Isopoda) were associated with deep hay (10-15 cm). The optimum amount of hay may therefore vary among different groups of arthropods. The effects of shading and mulch depth, and potential interactions between them, were tested using habitat patches created with varying degrees of shading (none, 50% or 90% shading) and two depths of woodchip mulch (3-5 cm or 10-15 cm deep). The presence of shading, at both 50% and 90%, encouraged colonisation of habitat patches by arthropods characteristic of rainforest. However, only the more complete shading treatment (90%) inhibited re-invasion of restored patches by arthropods from the surrounding pasture habitat. Effects of mulch depth were significant only for rainforest-associated ant species which responded positively to shallow mulch within shaded plots. These results suggest that moderate levels of canopy closure, as produced by tree spacings typical of timber plantations, may be sufficient to facilitate colonisation of reforested land by rainforest arthropods. However, greater canopy shading (90%) is likely to be needed to inhibit re-invasion of arthropods from surrounding pasture habitat. Using deeper woodchip mulch does not necessarily create more suitable conditions for rainforest arthropods or offset the deleterious effects of the lower levels of shading. Paired herbicide-treated and control plots were created within rainforest remnants to test the short- (approximately three days) and long-term (approximately three months) impacts of herbicide application on soil and litter arthropod assemblages on the floor of the remnant rainforests. The results found no deleterious effects of glyphosate herbicide formulated as Roundup® Biactive™ on rainforest soil and litter arthropods; hence, this herbicide appears suitable for the control of unwanted plants in rainforest restoration projects, from the perspective of arthropod biodiversity. The outcomes of this study also have a number of important implications for the monitoring of the development of soil and litter arthropod assemblages in restored rainforests. First, pitfall traps (a commonly used sampling technique) can provide sufficient information on the state of arthropod assemblages in the context of subtropical rainforest restoration projects, although samples collected by this method alone do not necessarily represent the whole suite of soil and litter arthropods (e.g. cryptic arthropods that live in soil and litter). Second, a combination of higher-taxon sorting of all arthropods, together with species-level sorting of a significant major taxon (ants), provides a feasible compromise between comprehensiveness and detail in monitoring responses of arthropods. Third, ‘composite habitat indices’, such as those developed in this study to quantify the extent to which a site resembles rainforest or pasture in terms of its arthropod assemblage, can help alleviate problems associated with the patchy distribution of arthropod taxa in monitoring samples. The experimental approach adopted in this study provided information that would otherwise have been limited by post-hoc empirical studies alone. This study’s results demonstrated that the selected aspects of different restoration techniques and management affect the colonisation of soil and litter arthropod assemblages in rainforest restoration of old fields.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Faculty of Science, Environment, Engineering and Technology
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Grainger, A. "The future role of the tropical rain forests in the world forest economy". Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377888.

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Ofori, Daniel Aninagyei. "Genetic diversity and its implications for the management and conservation of Milicia species". Thesis, University of Aberdeen, 2001. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU142070.

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This study describes the population genetic structure of Milicia species sampled from different provenances distributed over 5 countries (Sierra Leone, Cote d'Ivoire, Ghana, Cameroon and Tanzania). Random amplified polymorphic DNA (RAPD) and inter sample sequence repeats (ISSR) variation in 41 accessions from 5 different populations were consistent with each other. Analysis of molecular variance partitioned RAPD and ISSR variation into within- and between-population components. The between-population variation component was large, accounting for 62.2% and 71.5% for RAPD and ISSR respectively. Dendrogram analysis produced 2 major clusters separating dry zone accessions (mainly M. excelsa) from moist/wet zone accessions (mainly M. regia). Sub-clustering further separated accessions by forest type and/or geographic region. Phylogenetic analysis of chloroplast genes involved the use of nucleotide sequencing, restriction fragment length polymorphism (RFLP), and microsatellites. Only one region (5' to trnS) out of 6 regions analysed was polymorphic and revealed 3 different cytotypes. The distribution of the cytotypes matched with the 2 major clusters produced by the dominant markers. Wet/moist and dry zone bands were identified with little evidence of gene flow between populations. Seed mediated gene flow estimated from the chloroplast analysis was small (Nm = 0.23). To relate these molecular information with Phytolyma resistance, field provenance and progeny trials were conducted. Accessions from wet/moist zones were more tolerant to Phytolyma than accessions from dry zone. The data also suggest that accessions bearing the wet/moist zone specific markers have a high probability of being tolerant to Phytolyma. The approaches outlined and the results have general applicability in the sustainability of Milicia spp. and are discussed in relation to germplasm sampling, management and conservation of genetic recourses of Milicia species.
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Nik, Abdul Rahim H. "The effects of selective logging methods on hydrological parameters in Peninsular Malaysia". Thesis, Bangor University, 1990. https://research.bangor.ac.uk/portal/en/theses/the-effects-of-selective-logging-methods-on-hydrological-parameters-in-peninsular-malaysia(9ed5e3d1-33ab-4cb1-91b0-7c043891921f).html.

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An experimental forest watershed, consisting of three small catchments at Berembun, Negeri Sembilan, in Peninsular Malaysia has been monitored from 1979 to 1987. Adequate instruments were installed for continuous collection of hydrologic and climatic data. The calibration and post-treatment phases lasted for three and four years respectively. Two types of treatments were imposed -namely commercial selective logging and supervised selective logging in catchment 1 and catchment 3 whilst catchment 2 remained as a control. Pertinent logging guidelines were prescribed and assessed in C3 in terms of hydrological responses. Significant water yield increases were observed after forest treatment in both catchments amounting to 165 mm (70%) and 87 mm (37%) respectively in the first year; increases persisted to the fourth year after treatment. Magnitude and rate of water yield increase primarily depended on the amount of forest removed and the prevailing rainfall regime and the increase was largely associated with baseflow augmentation. Interestingly, both types of selective loggings produced no significant effect on peak discharge while the commercial logging resulted in a significant increase in stormflow volume and initial discharge. Such responses can be explained by the extensive nature of selective logging which normally left a substantial area of forest intact and minimal disturbance to flow channels. Thus, conservation measures introduced in this study - the use of buffer strips, cross drains, an appropriate percentage for the forest road network,- were found to be effective and beneficial in ameliorating the hydrological impacts.
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Krause, Alena [Verfasser]. "Changes in trophic niches of oribatid mites with transformation of tropical rainforest systems - from rainforest into rubber and oil palm plantations in Sumatra, Indonesia / Alena Krause". Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2021. http://d-nb.info/1224681703/34.

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Robinson, Nicole. "The influence of light environment on nitrogen assimilation in Rainforest species /". St. Lucia, Qld., 2003. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17329.pdf.

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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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Torrico, Albino Juan Carlos. "Balancing natural and agricultural systems in the Atlantic Rainforest of Brazil". [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=98299589X.

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Hero, Jean-Marc y n/a. "Predation, Palatability and the Distribution of Tadpoles in the Amazon Rainforest". Griffith University. Division of Australian Environmental Studies, 1991. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20050902.155749.

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A variety of aquatic habitats with different levels of potential predators are available to larval amphibians in Central Amazon rainforest. The anuran community at Reserva Florestal Adolfo Ducke, 25 km east of Manaus, Amazonas, Brasil, was studied to determine which species have eggs and/or larvae in water and how those larvae are distributed in time and space. The temporal and spatial distribution of potential predators as well as abiotic characteristics of these waterbodies were determined simultaneously to test for correlations with the distribution of tadpoles. The distribution of tadpoles was strongly related to fish predation pressure. Several tadpole species were found only in waterbodies with high fish abundance and thus have the ability to survive with fish. Most of these tadpoles were found to be unpalatable in controlled experiments. Unpalatability is the major adaptation allowing the coexistence of tadpoles and fish and is thus a major factor affecting tadpole community composition in this system. Controlled experiments showed that fish do not eat anuran eggs while the tadpoles of Leptodacrylus knudseni and Osteocephalus taurinus ate all types of eggs offered. The percentage of anurans with aquatic oviposition was positively related to fish abundance and negatively related to the occurrence of species of tadpole that ate eggs in experiments. These findings suggest that the present patterns of anuran distribution represent an evolutionary response to predation on the eggs and larvae. Contrary to the models of Heyer et al. (1975) and Wilbur (1984), desiccation and predation-pressure were not the major factors affecting species richness within waterbodies of the RFAD rainforest. In support of the model of Heyer et al. (1975), anuran species richness was correlated with the size of the waterbody. This could be because the size of the waterbody is related to increased complexity and availability of microhabitats. The range of volumes of waterbodies was also found to directly affect species richness of the RFAD community. While predation appeared to have a limited effect on species richness of individual ponds, predation-pressure was found to have a major influence on species composition. Anuran eggs and larvae survived with specific predators by possessing particular survival-traits (e.g. unpalatability and oviposition strategies). However, survival-traits were not effective against all predators in all habitats. The distribution of different predators among ponds provides a patchy environment on a local scale (i.e. within ponds). When combined with the variety of survival-traits exhibited by the anuran species, this spatial patchiness in predation contributes towards species richness within the anuran community of the RFAD rainforest.
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