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Tesi sul tema "Rain forests"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 30 luglio 2024

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1

Manokaran, N. "Population dynamics of tropical forest trees". Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources, 1988. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=59678.

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2

Ramdass, Indarjit. "Modelling forest dynamics and management of natural tropical rain forests". Thesis, University of Edinburgh, 1987. http://hdl.handle.net/1842/11890.

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3

Nascimento, Marcelo T. "A monodominant rain forest on Maraca Island, Roraima, Brazil : forest structure and dynamics". Thesis, University of Stirling, 1994. http://hdl.handle.net/1893/21893.

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A forest type dominated by Peltogyne gracilipes Ducke (Caesalpiniaceae) occurs on Maraca Island on a range of soil types. Maraca is located in Roraima State (Brazil) in the Rio Uraricoera and has an area of about 100,000 ha. This study compares the structure and floristic composition of the Peltogyne forest with the most widespread lowland forest type on Maraca and investigates some factors that could be involved in the persistent monodominance of Peltogyne. Three 0.25 ha plots were set up in each of three forest types: Peltogyne-rich forest (PRF), Peltogyne-poor forest (PPF) and forest without Peltogyne (FWP). Within each plot all trees (~ 10 cm dbh) were recorded. Seedlings and saplings were sampled in sub-plots of 2 m x 1 m (seedlings) and 4 m x 4 m (saplings). In the PPF and FWP, Sapotaceae were the most important family with the highest dominance and relative density values. Caesalpiniaceae showed high values in the PRF and PPF. Licania kunthiana, Pradosia surinamensis and Simarouba amara occurred in the forest types. Peltogyne dominated had 20% of stems and 53% of the trees ~ 10 cm dbh, and 91% of the canopy layer the canopy in total basal stems and 97% in all the the PRF and area of all of the total basal area of individuals > 50 cm dbh. In PPF, Lecythis corrugata and Tetragastris panamensis were the most abundant species, followed by Peltogyne. In the FWP the most abundant trees (~ 10 cm dbh) were L. kunthiana and P. surinamensis. In general, Peltogyne had low rates of seed predation and herbivory, but suffered locally high levels of damage to its seeds by leaf-cutter ants and was once observed to have an infestation of larvae of the moth Eulepidotis phrygionia on its young leaves. Peltogyne had no allelopathic effects on tested species and had VA mycorrhizal associations. Its occurrence remains unexplained but is most clearly correlated with soil magnesium.

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4

Valencia, Niels. "Ecology of forests on the western slopes of the Peruvian Andes". Thesis, University of Aberdeen, 1990. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=128343.

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Dry cloud forests on the western slopes of the Peruvian Andes were mapped from aerial photographs, 306 stands being recorded from 4^o50'S to 12^o47'S. The frequency and area of these stands, as well as most parameters analyzed in the eight sample sites, show a steep decreasing latitudinal trend and are strongly correlated with the latitudinal rainfall gradient. The mean area of the forest stands decreases from 115 ha in northern Peru to 42 ha in central Peru. The number of species recorded decreases along the study area from 52 to 13 and there is a well defined latitudinal sequence of species. Mean density and basal area per hectare of stems ≥10 cm gbh decreases from 2995 individuals and 79.91 m^2 in the north to 500 individuals and 17.27 m^2 in central Peru. The vertical structure is similar throughout the study area, emergent trees reaching on average 22 m and the main canopy 12 m in the north and 13 m and 7 m respectively in central Peru. Regeneration is very active in northern Peru. Juveniles have been found for a high proportion of species, including all common ones, and most species show a logarithmic decline in number of stems with increasing girth. There is a steep decreasing trend towards central Peru, where few species regenerate, mostly shrubs. The pattern found may be the result of the combined effect of grazing and a climatic change towards drier conditions evidenced in the regeneration pattern of most sites.

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5

Poels, R. L. H. "Soils, water and nutrients in a forest ecosystem in Suriname". Wageningen : Agricultural University, 1987. http://catalog.hathitrust.org/api/volumes/oclc/23819734.html.

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6

Latifah, Sitti. "Inventory and quality assessment of tropical rainforests in the Lore Lindu National Park (Sulawesi, Indonesia) /". Göttingen : Cuvillier, 2005. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=013215823&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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7

Luizao, Regina C. C. "Soil biological studies in contrasting types of vegetation in central Amazonian rain forests". Thesis, University of Stirling, 1994. http://hdl.handle.net/1893/2274.

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Studies were carried out in a lowland evergreen rain forest (LERF), on an ultisol, in the 'Reserva da Campina', 45 km north of Manaus, and in two facies of the highly distinct formation called heath forest, on spodosols. The spodosols had a layer of mor humus of thickness varying from nil in some parts in the smaller facies of heath forest (SHF) to 35 cm in the taller facies (THF). The overall aim was to investigate the forest soil biota and its role in nutrient turnover by comparing the SHF, THF and LERF. Microbial biomass, soil respiration and nitrogen transformation rates were measured in the three forest types in both wet and dry seasons. Field and laboratory fertilization experiments were made to investigate potential limiting nutrients for microorganisms and plants. The role of fine roots in decomposition and litter animal colonization was assessed in litter bag studies. SHF soils have a small microbial population with no net nitrification in any season. THF soils showed a variable microbial population adapted to high acidity, which immobilises nitrogen during the wet season, but which allows a net release during the dry season. LERF showed the most diverse population which causes mineralization and nitrification in both seasons. A bioassay with nutrient addition showed that the low pH, and nitrogen and sulphur supply were likely to be limiting nitrogen dynamics in all forest types, but especially in THF and LERF. The ingrowth bags showed that despite the lower values of fine root growth in the SHF (particularly when the white sand of the spodosol was used as the substrate), the roots showed in all plots an increased production with added calcium as carbonate or sulphate. In the decomposition bioassay to evaluate the role of roots in the nutrient turnover it was shown that in all forest types there was no effect of roots on the mass loss of Clitoria leaves but there was a significant effect on concentrations of some nutrients. In general, roots contributed to the accumulation of aluminium and iron and to a faster release and uptake of calcium, magnesium and zinc. A survey of the mycorrhizal associations in all forest types showed that both VAM and ECM fungi with some unknown VAM fungal species are common. VAM and ECM adaptation to low pH and high phenolic compounds in the soils may be important in the maintenance of these ecosystems.

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8

Abebe, Tarekegn. "The influence of selective logging on residual stand and regeneration in a rain forest in southwestern Ethiopia /". Umeå : Swedish University of Agricultural Sciences, 2003. http://diss-epsilon.slu.se/archive/00000213/.

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Thesis (doctoral)--Swedish University of Agricultural Sciences, 2003.
Thesis documentation sheet inserted. Appendix includes five manuscripts submitted for publication elsewhere, four co-authored with others. Includes bibliographical references.

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9

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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10

Tomlinson, Francis J. "Do harvesting impacts determine patterns of non-forest vegetation in Dipterocarp Forest in Sabah 15 years post logging?" Available from the University of Aberdeen Library and Historic Collections Digital Resources, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=59623.

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11

Brown, David W. "Why governments fail to capture economic rent : the unofficial appropriation of rain forest rent by rulers in insular southeast Asia between 1970-1999 /". Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/10754.

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12

Hogan, Anthony David. "Australia's native forest and rainforest timber usage and the plantation strategy alternative /". Title page, table of contents and abstract only, 1992. http://web4.library.adelaide.edu.au/theses/09ENV/09envh714.pdf.

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13

Silva, J. N. M. "The behaviour of the tropical rain forest of the Brazilian Amazon after logging". Thesis, University of Oxford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.276556.

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14

Bellingham, Peter John. "The effects of a hurricane on Jamaican montane rain forests". Thesis, University of Cambridge, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283931.

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15

Costanzo, Angela J. "A quantitative survey of riparian forest structure along the Quebrada Grande in La Cangreja National Park, Costa Rica /". Thesis, Connect to this title online, 2006. http://www.ranchomastatal.com/docs2/php5pk7ty%5FRiparianForestStructure%5FCostanzo.pdf.

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16

Brinkley, Nancy Jane. "Rain forest curriculum for upper elementary and middle grades". CSUSB ScholarWorks, 1996. https://scholarworks.lib.csusb.edu/etd-project/1267.

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17

Samsoedin, Ismayadi. "Biodiversity and sustainability in the Bulungan Research Forest, East Kalimantan, Indonesia : the response of plant species to logging". Thesis, University of Stirling, 2007. http://hdl.handle.net/1893/224.

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This study reports forest structure, regeneration and the soil properties from unlogged and logged forest in the Bulungan Research Forest, Malinau District, East Kalimantan, Indonesia. Four sites were compared by using four 1-ha replicate plots in each of primary forest (PF), 5, 10 and 30-yr old logged forest (LF-5, LF-10, LF- 30). The tree species composition differ among forest types, as it was shown that the mean value of similarity indices for all pairs were 0.215 (for the Jaccard index) and 0.353 (for the Sorensen index). The low values for similarities among forest types were most probably caused by low numbers of species shared between each forest type. Both correlation values, r = 0.023 for Jaccard index and r = 0.031 for Sorensen index, showed no strong correlation between the similarity index (C) and the distance between forest types. This supports the use of a chronosequence approach. A total of 914 tree species with ³ 10 cm dbh were recorded from 223 genera and 65 families. There were no significant differences in mean species numbers (166 – 180/ha) among treatments. Mean density of species was lower in LF-5 and LF-10 (501/ha) than in PF or LF-30 (605/ha and 577/ha); similarly to mean basal area (LF-5, 28.5 m2/ha; LF-10, 32.6 m2/ha) vs. PF (45.8 m2/ha) and LF-30 (46.9 m2/ha). Dead wood on the forest floor was significantly higher in LF-10 (75 m3/ha) than in the other treatments. Seedlings (< 2 cm dbh) of 1,022 species were recorded from 408 genera and 111 families. The mean number of tree seedling species ranged between 170-206; the mean density of seedlings was about two-fold lower in LF-10 (2790/ha) than in the other treatments. Saplings (>2 – 9.9 cm dbh) of 802 species belonged to 241 genera and 65 families. There was a high variability in species richness across treatments (89 – 191/ha), but not in stem numbers. The Dipterocarpaceae family was dominant in all treatments, followed by the Euphorbiaceae. The soils were acidic, low in nutrients and had low to very low fertility. Both primary and logged forest areas are marginal or not suitable for sustained production of plantation crops. Logging caused soil compaction in LF-30. Although in terms of number of species and trees, amount of BA, number of saplings and seedlings LF-30 appeared to have satisfied prescriptions for a second harvest, ecologically the forest is far from mature. The Indonesian Selective Cutting and Replanting (TPTI) system may need to be revised to a 35 – 45 year cycle to ensure long-term forest productivity in terms of not only timber but other goods and ecosystem services, the value of which are never quantified in monetary terms, but can be higher than the timber revenue.

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18

Ellis, Alexander 1972. "Global change and tropical forests : functional groups and responses of tropical trees to elevated CO". Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=27312.

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The paradox of tropical forests is that they are simultaneously the most diverse, the least understood, and the most imperiled terrestrial ecosystem in the world. Dramatic increases in the atmospheric carbon dioxide (CO$ sb2$) concentration threaten to adversely affect fundamental climatic and ecosystem processes, gradually changing many things which we do not yet understand. Although the impacts of this rise have been studied in temperate areas, little research has investigated tree responses in the tropics, especially under natural frost conditions. This thesis examines three central issues in tropical ecophysiology and global change. First, it investigates the feasibility of in-situ measurements of several physiological traits under heterogeneous environmental conditions in a Panamanian rainforest. Second, it studies whether physiological traits differ among species and which traits are most consistent with ecological niche. Finally, it explores how variable species are in response to elevated CO$ sb2$. If ecologically-defined functional groups were to remain physiologically similar under increased CO$ sb2$, they could be used in accurately representing the variation at the species level in a global change model of system-level responses. (Abstract shortened by UMI.)

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19

Floyd, William Charles. "Snowmelt energy flux recovery during rain-on-snow in regenerating forests". Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/42977.

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Rain-on-snow (ROS) is a major contributor to flooding and landslides in many temperate coastal watersheds around the world. Research has shown that forest harvesting can increase melt rates during ROS at both the stand and watershed scale. Because of this, post disturbance hydrological recovery is of interest in watersheds where forest management is prevalent. Recent research that pairs events by frequency rather than chronologically has indicated that forest cover removal can have a significant effect on the magnitude and frequency of extreme events, which is counter to the dominant view in forest hydrology. Hydrological modelling provides a means to apply frequency based analysis in watersheds with short data records, but models must be tested and validated in coastal watersheds before they can be applied extensively. A key challenge to testing models is the inherent difficulty with collecting data in ROS environments. Therefore, the objectives of this research were to design a methodology that recorded previously unobserved processes, use these data to validate model simulations and assess stand level energy flux recovery during ROS. Data were collected at a range of elevations within recently harvested, regenerating and old growth forests. The Cold Regions Hydrological Model generally performed well at capturing the dynamics of snow accumulation and melt, however, snow water equivalent was generally over-predicted. Depths of transient snowpacks were generally under-predicted, however, once a snowpack was established model performance improved. Clear-cut forests had higher mean and greater variability of energy inputs resulting in large events occurring more frequently than in old or second growth forests. Energy flux recovery was evident within the regenerating forests; however, both the rates of recovery and differences among stands depended on the location and the variables compared. When either the mean or standard deviation of energy inputs differed from that of old growth forests, energy flux recovery was reduced as events became larger and less frequent. It is probable that results obtained from this study will translate to stream flow in watersheds with steep slopes, shallow soils and extensive preferential flow networks (i.e. high run-off coefficients), especially when run-off generating areas are synchronized.

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20

McConkey, Kim Rachelle. "Gibbons as seed dispersers in the rain-forests of central Borneo". Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.431300.

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21

Echeverría, Cristian Mauricio. "Fragmentation of temperate rain forests in Chile : patterns, causes and impacts". Thesis, University of Cambridge, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.615028.

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22

Debski, Igor. "Mechanisms of coexistence among Aporosa species in two Malaysian rain forests". Thesis, University of Aberdeen, 2000. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU602015.

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Tropical forests contain the greatest biotic diversity of any biome, and those of South-east Asia are amongst the most diverse and tree species rich. I studied the speciose understorey tree genus, Aporosa (Euphorbiaceae), at two c. 50 ha plots in Malayisa, at Lambir Hills National Park, Sarawak, and at Pasoh Forest Reserve Peninsular Malaysia, where 17 and 12 species co-occur, respectively. The aim of this study was to determine which factors influence the spatial distribution of Aporosa species, what limits their abundance, and ultimately what are the mechanisms of coexistence among the species of this genus. Using a method of second-order spatial pattern analyses based on Ripley's K function to test for non-random spatial distributions, and to test for spatial associations between species (using a bivariate method) I found that Aporosa species formed spatially distinct assemblages at both sites. A randomization procedure suggested that these assemblages were explained by biases in the distribution of species in relation to habitat types. Soil type, as determined by parent material, was an important determinant of habitat preferences, although topography and forest stmcture also accounted for some variation. I found measurable effects of position on soil and especially topographic types on mortality and recruitment rates of many Aporosa species. Growth rates over a 5-8 year period varied between species, but, perhaps due to the short time interval and the correlation between abiotic variables, they were a poor indicator of habitat preference as defined by bias in a species' distribution. Aporosa species exhibit a range of morphological, anatomical and biochemical properties, and I found evidence that both habitat partitioning and density-dependent mortality of juveniles occurred. These are both mechanisms contributing to the maintenance of species richness. A severe drought had differential effects on mortality rates of Aporosa species and may be important in determining species' spatial distributions and abundance. Therefore disturbance events are also likely to be important mechanisms, as are non-equilibrium random population fluctuations, between ecologically similar species.

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23

Mitchell, Thomas Carly. "The ecology of Macaranga (Euphorbiaceae) trees in primary lowland mixed Dipterocarp forest, Brunei". Thesis, University of Cambridge, 1994. https://www.repository.cam.ac.uk/handle/1810/251702.

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24

Coomes, David Anthony. "The effects of root competition on saplings and seedlings in Amazonian caatinga forest in southern Venezuela". Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361641.

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25

Zakaria, Maziah. "Colletotrichum diseases of forest tree nurseries in Malaysia". Thesis, University of Bristol, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295495.

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26

Pendry, Colin A. "Ecological studies on rain forests at three altitudes on Bukit Belalong, Brunei". Thesis, University of Stirling, 1994. http://hdl.handle.net/1893/3502.

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Altitudinal zonation of rain forests was investigated on Bukit Belalong (913m), Brunei. Mean annual rainfall was 4100mm at 45m and 5500mm at 913m. Mean annual temperatureswere 25.7°C (45m) and 21.8°C (913m). Three 0.25ha plots were set up at each of three altitudes. At 200m and 500m there was evergreen lowland rain forest and at 850m there was lower montane rain forest (LMRF). The Dipterocarpaceae had the highest proportion of basal area throughout, but their importance declined in the LMRF where the Fagaceae, Myrtaceae and Lauraceae were increasingly important. Soils in the LMRF were more organic and had higher concentrations of total nitrogen and phosphorus and the soils from 500m were the most acid and least base saturated. Rates of nitrogen mineralisation and soil concentrations of inorganic nitrogen did not differ significantly among altitudes. The rates (t ha-1 yr-1) of total small litterfall and leaf litterfall were significantly lower in the LMRF (10.6 and 7.9 at 200m; 10.5 and 7.9 at 500m; 8.3 and 6.0 at 850m). Litterfall nutrient concentrations were similar among altitudes, but smaller quantities of litterfall nutrients were cycled at 850m. The mass (t ha-1) of the small litter layer was similar throughout (5.2 at 200m; 6.1 at 500m; 5.2 at 850m) but leaf litter kL values were lower at 850m (2.4 at 200m; 2.4 at 500m; 2.0 at 850m). Fine root (<5mm) mass (t ha-1) in the top 100cm of soil was 8.3 (200m); 12.0 (500m); 10.6 (850m). Rates (t ha-1 yr-1) of fine root growth (estimated by ingrowth bags) were 0.9 (200m); 2.2 (500m); 0.5 (850m). A bioassay experiment using rice was made at 30m and 913m. Nutrients were more limiting in the montane soil, but climate was of overriding importance for rice growth. It seems that the LMRF is not nutrient limited and the lower temperatures at 850m are the primary cause of the change in species composition and reduction of stature there.

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27

Wilebore, Rebecca. "Valuing forests in tropical landscapes in the context of REDD+". Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709048.

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28

Cunningham, Shaun Cameron 1971. "Comparative ecophysiology of temperate and tropical rainforest canopy trees of Australia in relation to climate variables". Monash University, Dept. of Biological Sciences, 2001. http://arrow.monash.edu.au/hdl/1959.1/9040.

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29

Baker, Timothy Russell. "Spatial and temporal patterns of growth in Ghanaian tropical rain forest". Thesis, University of Aberdeen, 2000. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU603191.

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This thesis tests the hypothesis that variation in water supply, nutrient availability and irradiance determined variation in tree growth along local and regional gradients of resource availability, and over time, in Ghanaian forests. Regional variation in soil water availability determined seasonal patterns of diameter change of Celtis mildbraedii and Strombosia glaucescens in semi-deciduous and evergreen forest, over two years. However, in a semi-deciduous forest, annualized diameter increment of Celtis mildbraedii was higher in summit and slope, compared to valley, positions after two years, even though trees in valley positions experienced a shorter effective dry season. Growth was also greater in the semi-deciduous than the evergreen forest in the second year of the study. These patterns suggest that concentrations of N in soil over topographic gradients, and concentrations of available P and the base cations over regional scales, may be important determinants of growth. Dry season stem shrinkage in semi-deciduous forest can comprise up to 0.5% of tree diameter, and varies between years. Re-enumeration of forest plots in seasonal climates should be carried out over whole year intervals, during the wet season, to minimise bias derived from variation in tree water status. In a semi-deciduous forest, no relationship was found between topography and six year growth rates of two common species or of six functional types defined on the basis of regeneration strategy and regional distribution pattern. However, within this forest, and in a comparison within five different forests across the regional gradient of rainfall and soil fertility, pioneer species with distributions biased towards drier forests had significantly higher growth rates than pioneer species associated with wetter forests. Variation in growth of dry forest pioneer species explained more than half the total variation in stand-level growth rates, demonstrating that it is the presence of abundant, potentially large, fast growing pioneer species in more seasonal forest types that generate regional scale variation in forest growth. These results indicate that the environmental variables found to determine growth are dependent on the scale of the study and the magnitude of the gradient in resources being compared. Variation in soil fertility over regional rainfall gradients in tropical forests has a significant impact on variation in tree growth, within and between species, and at the stand-level.

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30

Tinambunan, Djaban. "Strategic planning models for timber harvesting operations in the tropical rain forests of Indonesia /". Thesis, Connect to this title online; UW restricted, 1986. http://hdl.handle.net/1773/5525.

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31

Still, Margaret Jean. "Population dynamics and spatial patterns of Dipterocarp seedlings in a tropical rain forest". Thesis, University of Stirling, 1993. http://hdl.handle.net/1893/26682.

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Population dynamics and spatial pattern of dipterocarp seedlings were investigated in lowland dipterocarp forest in Danum Valley Conservation Area, Sabah, East Malaysia. Seedlings (< 10 cm gbh) were enumerated in two areas (2.0 and 0.48 ha) within the tree enumeration plots established by the University of Stirling project, and surveyed over 22 months. Seedlings of the major canopy and emergent dipterocarps in the area were common: Shorea johorensis (Red Meranti); S. argentifolia, S. leprosula, S. parvifolia (Light Red Merantis, LRM) and Parashorea maleanonan, all light demanding species; S. fallax,S. pauciflora (Dark Red Meranti, DRM), more shade tolerant emergent species; and Hopea nervosa, Vatica dulitensis and V. sarawakensis, shade tolerant canopy species. Total seedling densities were 2000-2500 ha-1. Mortality rates varied from 0 to 16% yr-1 in different species, and were highest in the LRMs and lowest in the canopy species. Temporal and spatial variation in mortality rates was greatest in the LRMs. In both plots, seedling mortality rates were significantly positively correlated with basal area of conspecific trees ≥10cm gbh. Net growth rates were very variable, even within size classes in the same species. Median growth rates were highest in the LRMs and lowest in canopy species. Frequency distributions of growth rates were strongly leptokurtic in slow-growing species, with most seedlings having growth rates around zero, although individual seedlings could produce large increments. In fast-growing species, more seedlings achieved high growth rates. A significant proportion of seedlings suffered height loss due to falling debris, and almost half the seedlings showed evidence of previous stem damage. Large growth increments were recorded in most species in response to canopy openings, usually very small gaps caused by branch falls. Individual increments exceeded 1 m yr-1 in seven species. Growth and mortality rates were significantly positively correlated across species in Plot 1, but not in Plot 2. Seedling spatial patterns were examined in eleven species in Plot 1, and covered a wide range of degrees of aggregation. Seedlings of the light-demanding emergent species were we1l-distributed throughout the study area, though some showed aggregation at a small scale. DRM seedlings were strongly clumped around adult trees. Seedlings of two of the canopy species were very strongly aggregated around adult trees, while the third species, V. sarawakensis, had randomly distributed seedlings.

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32

Morris, Michael William. "Amazopoly a game of survival in a tropical rain forest". CSUSB ScholarWorks, 1996. https://scholarworks.lib.csusb.edu/etd-project/34.

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33

Rembold, Katja [Verfasser]. "Conservation status of the vascular plants in East African rain forests / Katja Rembold". Koblenz : Universitätsbibliothek Koblenz, 2011. http://d-nb.info/101343739X/34.

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34

Cavelier, Jaime. "Root biomass, production and the effect of fertilization in two tropical rain forests". Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.257466.

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35

Hidaka, Amane. "The pattern and mechanisms of phosphorus-use efficiency of Bornean tropical rain forests". 京都大学 (Kyoto University), 2011. http://hdl.handle.net/2433/142420.

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36

Orlando, Heloisa Helena R. V. "The fragmented forest : environmental conservation and legal protection in reserve areas in the Brazilian Amazon rain forest". Thesis, University of Nottingham, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284285.

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37

Pearson, Audrey F. "Natural disturbance patterns in a coastal temperate rain forest watershed, Clayoquot Sound, British Columbia /". Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/5513.

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38

Sioh, Maureen Kim Lian. "Fractured reflections : rainforests, plantations and the Malaysian nation-state". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0018/NQ48715.pdf.

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39

Evans, David Paul. "Biological indicators of forest dieback". Thesis, University of South Wales, 1992. https://pure.southwales.ac.uk/en/studentthesis/biological-indicators-of-forest-dieback(514886c2-00a0-4280-aca2-a500e3e794cb).html.

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This study involved the determinations of the foliar levels of chlorophyll a and b and metal levels in the year 1, year 2 and year 3 needles of Sitka spruce. A survey was made of nineteen sites in the Afan 1 forest in South Wales. The results obtained indicates that there are two distinct types of site, namely good growth sites and poor growth sites. The poor growth sites were found to be at higher elevations. Further analyses of the results show that there is possibly an increased loss of nutrients from the trees at the poor growth sites. This may be due to increased pollution that may be present at the higher elevations. In 1987 a survey was made of the one year old epicormic tissues that were compared with the normal tissues at the 19 sites of the Afan 1 Forest There were no statistically significant differences in the levels of the chlorophylls or in any of the metals that were looked at. At the Afan 1 Forest there are observed pairs of trees that are growing quite close together, but they exhibit quite a marked difference in growth. One of the pair shows vigorous healthy growth, whilst the other is stunted and shows symptoms of decline. One such pair is found at Site 15. They are of the same age and from the same seed stock. It was found that over an eight month period, the stronger growing of the pair had significantly higher levels of chlorophyll a and b, potassium, calcium and magnesium. This may indicate increased leaching and foliar damage from the poorer growing of the pair. Three more pairs of trees together with their grafts were examined from sites' 1,5 and 6, for their levels of peroxidase enzymes. Peroxidase has been used to determine possible genetic differences in cultivars. The work yielded very little useful information. The SCOR-UNESCO equations have been widely used as a means of determining chlorophyll levels from plant extracts. A multivariate calibration method was used in conjunction with HPLC to determine the accuracy of these equations for determining the levels of chlorophyll and b. The results show revealed that the equations appear to be underestimating the chlorophyll a levels. Leading on from the HPLC work, a novel method for the separating a mixture of chlorophyll a and b was developed using packed column SFC. The method appears to be quite promising with its better resolution and faster analysis times as compared to FIPLC methods. Sitka spruce seedlings were grown in COIR (coconut husk) and were used in and were used in a central composite design to determine the effects of cadmium and copper, both singly and in combination would have upon their growth. Response surface methodology was used to determine the effects and it was found from the experiment that high levels of cadmium appeared to have an effect upon the elongation of the needles of the new shoots.

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40

Ndam, Nouhou. "Tree regeneration, vegetation dynamics and the maintenance of biodiversity on Mount Cameroon : the relative impact of natural and human disturbance". Thesis, Bangor University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285517.

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41

Matos, Dalva Maria da Silva. "Population ecology of Euterpe edulis Mart. (Palmae)". Thesis, University of East Anglia, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296949.

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1- The ecology of a population of the tropical palm tree Euterpe edulis Mart. was studied at the Municipal Reserve of Santa Genebra, Campinas (Sao Paulo, Brazil). This palm has been intensively exploited due to the quality of its heart of palm (palmito). The heart of palm corresponds to the apical meristem of the plant together with the developing new leaves. 2- The indiscriminate exploitation that this palm has been subject to over recent years in southern Sao Paulo may result in it becoming extinct in many forest fragments. The biodiversity of large animals in these forests has declined as a consequence of hunting, and the overexploitation of E. edulis has also led to a decline in the number of large frugiverous birds. The financial benefits generated by the sustainable exploitation of palmito can exceed those from a single extraction or those from forest conversion to agriculture. 3- The seed and seedling ecology of the population of E. edulis was examined. On average each plant produced approximately 1500 fruits and, there was a tendency for plants of intennediate size to be slightly more fecund. Most seeds were found in close proximity to adult plants; the distance of dispersal could be described by a negative power curve. Five species of birds belonging to the Family Turdidae were observed to feed on the fruits of E. edulis while on the tree, while subsequent dispersal along the gro':lnd was found to occur by water. The probability of surviving and growing to the next Sl~ class was inversely related to the number of seedlings. The maximum survival of seedlIngs and growth to the next size class occurred approximately 4 m from adult plants, indicating that the survival and growth of seedlings was suppressed in the immediate vicinity of conspecific adults. 4- The spatial pattern of the population of E. edulis, in the Municipal Reserve of Santa Genebra, was significantly clumped. The data indicate that the spatial distribution of individuals becomes less clumped with time as individuals develop. 5- The transition matrix analysis of the population revealed that the population is increasing at a rate of 14% year-I. The highest sensitivity was observed in the transition from size-class 1 (0-10 mm diameter) to class 2 (10.1 - 20 mm). According to the elasticity analysis, most of the value of the finite rate of population increase is accounted for by the probability of surviving and remaining in the same size class. The results from the haryesting simulations, indicate that it is possible to harvest E. edulis sustainably when harvesting is restricted to size class 6 plants (Le. reproductive adults). 6- The density-dependence observed for survival and growth of plants in the smallest size class was s~ong enough to affect the population dynamics of E. edulis. Elasticity analysis of the transItion matrix shows that the position of populations of E. edulis in G-L-F space moves towards the L apex of the demographic triangle as the density of plants increases.

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42

Kaye, Maria Ellen. "The role of functional traits and phylogeny in assembly of tropical forest communities in Danum Valley, Sabah". Thesis, University of Aberdeen, 2016. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=231264.

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Tropical forests have been studied by community ecologists since the earliest days of the field because of their diversity and complexity and much of the theory behind community assembly has been developed in the tropics. However, the processes that act to assemble species in tropical forest across a very fine scale are still poorly understood. This study investigates community structure in 20ha area of hyper diverse tropical rainforest in Sabah, Malaysia. In order to examine community phylogenetic structure, I reconstructed a molecular phylogeny for all species in the study site using DNA barcoding loci. From this, I calculated phylogenetic diversity metrics for each community and then used a null model to compare observed phylogenetic diversity with that which would be expected if communities were randomly assembled with respect to phylogeny. The analyses showed that communities are more closely related than predicted by the null model. I also collected species functional trait data and showed that species assemblages and community weighted mean trait values correlate with environmental gradients on the plot. I also compared functional diversity to data simulated from null models. This showed that communities are on average more functionally similar than predicted at random. Finally, I performed a multivariate analysis with environmental, spatial, phylogenetic and trait data from communities across the plot. The analyses recovered an elevational and soil gradient that correlated strongly with community composition. Species occupying different ranges along this gradient had differing trait values and were phylogenetically distinct. These analyses demonstrate that even fine scale environmental variation is influential in assembling communities over a small area of forest. A soil nutrient gradient is consistently recovered that correlates with topography, suggesting that soil nutrient distribution is mediated by the downslope movement of water leaching soils on ridge tops and leading to accumulation of nutrients in valleys. This gradient is associated with species compositional variation and also with community weighted mean functional traits, indicating that the environment is influencing species distributions even over very small areas. Communities were both functionally and phylogenetically clustered, adding further support to this conclusion.

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43

Babweteera, Fred. "Interactions between frugivores and fleshy-fruited trees in primary and secondary tropical rain forests". Thesis, University of Oxford, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433409.

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44

Schaumann, Friederike. "Terricolous bryophyte vegetation of chilean temperate rain forests : communities, adaptive strategies and divergence patterns /". Berlin : J. Cramer, 2005. http://catalogue.bnf.fr/ark:/12148/cb401353009.

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45

Butt, Nathalie. "Patterns and trends in climate and ecosystem composition and dynamics in lowland Amazon rain forests". Thesis, University of Oxford, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.508755.

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46

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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47

Richards, Michael. "Economic incentives for the sustainable management and conservation of tropical forests". Thesis, University of South Wales, 2007. https://pure.southwales.ac.uk/en/studentthesis/economic-incentives-for-the-sustainable-management-and-conservation-of-tropical-forests(eb11e629-42d7-4fbf-924c-769ac6a42471).html.

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This PhD by Publication traces through 13 of my publications on economic incentives for forest management and conservation in tropical countries (with a regional bias towards Latin America), including several papers focused on participatory forest management or community-based conservation. The papers show how my thinking has evolved from a focus on market and nonmarket incentives, to an increasing emphasis on governance and regulatory incentives in explaining stakeholder behaviour to the forest resource, as well as the equity impacts. They reveal that positive incentives and win-win (environmental and poverty reduction) outcomes will only emerge when the underlying market, policy and institutional failures are tackled. Because of their public good values, the survival of tropical forests is contingent on the actions of the international community and governments. Sustainable forestry, therefore, depends on a combination of domestic governance progress to control illegal logging and the rent-seeking powers of vested interest groups, global governance regulations which create markets for environmental services, secure property rights for resident stakeholders and extra-sectoral policies that moderate land use opportunity costs. The current main hope for tropical forests is 'avoided deforestation' since this will need to tackle the forest governance problems and underlying multi-sectoral drivers of deforestation if it is to be successful. It represents a balanced market (payments for ecosystem services) and supply-side (improved governance) response to what is essentially a 'public goods' management problem, but will need to overcome some major political economy challenges.

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48

Rezende, Andreia Alves. "Comunidade de lianas e sua associação com arvores em uma floresta estacional semidecidual". [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315445.

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Orientador: Neusa Taroda Ranga
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-04T02:57:19Z (GMT). No. of bitstreams: 1 Rezende_AndreiaAlves_D.pdf: 680315 bytes, checksum: 35c8e450ad258314b9f2c48dbcf0cd7a (MD5) Previous issue date: 2005
Resumo: Lianas são plantas que germinam no solo, mantêm-se enraizadas durante toda a vida e necessitam de suporte físico para alcançarem o dossel. Elas são membros característicos das florestas tropicais, onde contribuem com cerca de 25% da diversidade vegetal. Às vezes, dominam a vegetação, principalmente em áreas perturbadas. Lianas competem com árvores por nutrientes e luz, e influenciam a taxa de crescimento e a mortalidade de sua árvore hospedeira. Embora as lianas iniciem sua escalada a partir do chão, muitas colonizam árvores vizinhas pelo dossel da floresta, ¿amarrando-se¿ às outras, podendo ocasionar a queda de várias árvores quando uma delas cai. Devido a sua abundância e o seu impacto sobre as árvores, é de grande importância conhecer os fatores que governam a distribuição e dinâmica das lianas na floresta tropical e, assim, desenvolver estratégias de uso sustentável. Assim, os objetivos desta tese foram: (1) avaliar a riqueza e abundância das lianas e (2) a relação das lianas com as características do hospedeiro e com a estrutura da floresta. O trabalho foi realizado em um fragmento de floresta estacional semidecidual, com cerca de 435,73 ha, na Estação Ecológica de Paulo de Faria, SP. Foram amostradas 100 parcelas de 10 x 10 m (1 ha). As lianas com diâmetro ³ 1 cm e as árvores ³ 3 cm enraizadas nas parcelas foram medidas no DAP (diâmetro à altura do peito - 1,30m) e identificadas. Amostrou-se 1427 indivíduos de 45 espécies de lianas, pertencentes a 14 famílias, sendo as mais ricas: Bignoniaceae (14 espécies), Sapindaceae (nove) e Malpighiaceae (seis), e as mais abundantes Bignoniaceae, Sapindaceae e Apocynaceae. A riqueza de lianas foi aproximadamente igual à metade (razão 0,51) da riqueza de árvores (87 espécies). A densidade média de lianas e árvores foi semelhante, cerca de 1400 indivíduos/ha. Melloa quadrivalvis (Bignoniaceae) foi a espécie mais comum na área estudada. Do total de indivíduos de lianas amostrados, 57,6% apresentaram diâmetros entre 1 - 2,5 cm, correspondendo a 95% da riqueza total amostrada. Das 1419 árvores amostradas, 53% carregavam pelo menos uma liana. As espécies menos infestadas que a média geral foram Inga marginata, Piper amalago, Trichia catigua e T. claussenii, e somente uma, Machaerium paraguariense, foi mais infestada que a média, considerando todas as espécies. Os resultados, de modo geral, não apoiaram a hipótese de especificidade entre espécies de lianas e espécies de árvores, pois a riqueza e a diversidade de espécies de lianas aumentaram com a proporção de infestação. Se houvesse especificidade, esperar-se-ia que uma espécie de árvore fosse mais infestada por uma determinada espécie de liana. O mecanismo de escalada das lianas não influenciou o número de árvores que cada liana escalou, embora tenha ocorrido associação positiva entre árvores com casca rugosa e lianas com gavinhas. Considerando-se as características individuais do hospedeiro, as árvores com diâmetros maiores apresentaram maior densidade de lianas. Com relação às características da vizinhança, as diferenças encontradas provavelmente se devem as condições de luminosidade do ambiente. As parcelas com maior proporção de árvores com DAP > 30 cm apresentaram relação negativa significativa com a densidade de lianas. A relação foi positiva em parcelas com maior proporção de árvores com copas £ 3 m de altura. Assim, as evidências deste estudo sugerem que a distribuição das lianas foi mais influenciada por características da comunidade do que pelas características das espécies de árvores presentes
Abstract: Lianas are soil-germinating plants, perennially rooted and which need support to reach the canopy. They are characteristically from the rain forests, where they contribute with near 25% of vegetal diversity. Lianas compete with trees for nutrients and light, influencing growth and mortality rates of its host tree. Although lianas begin their life on the ground, many of them colonize vicinity trees through the forest canopy, ¿tying¿ themselves to the others, and may cause the fall of many trees. Due to their abundance and impact over other trees, it is important to know the factors governing distribution and dynamics of the lianas in order to better understand the rain forest and to develop sustainable strategies. Thus, the aims of this study were: (1) to assess the richness and abundance of lianas, and (2) to establish the relation of lianas with the characteristics of the hosts and the structure of the forest. The research was carried out in a fragment of a Semideciduous Stational Forest with 435.73 ha, at the Paulo de Faria Ecological Station. The sampling consisted of 100 plots of 10 x 10 m (1 ha), allotted in an area of 4 ha. Lianas with a diameter ³ 1 cm and trees ³ 3 cm rooted in the plots were measured in DBH (diameter at breast height ¿1.30m) e identified. In the study area, 1427 individuals were sampled from 45 species of lianas, belonging to 14 families, the richest ones being Bignoniaceae (14 species), Sapindaceae (nine) e Malpighiaceae (six), and the more abundant Bignoniaceae, Sapindaceae e Apocynaceae, adding up to 80% of the sampled individuals. The liana richness was approximately equal to half (ratio 0.51) the tree richness (87 species). Average density of lianas and trees was similar, around 1400 individuals/ha. Melloa quadrivalvis (Bignoniaceae) was the most common species in the study area. From the total number of the sampled liana individuals, 57.6% presented diameters between 1- 2.5 cm, corresponding to 95% of the total sampled richness. Only 26 individuals presented diameter higher than 10 cm. From the 1419 trees with diameter ³ 3 cm, 53% carried at least one liana, with the higher rate of infestation (79%) occurred in the individuals with diameters > 10 cm. Species less infested than the expectation were Inga marginata, Piper amalago, Trichia catigua e T. claussenii. One species, Machaerium paraguariense, was more infested than the expectation. In general, results did not support the hypothesis of species-specificity between lianas and trees, since the richness and diversity of liana species increased with the infestation rate. Climbing mechanism did not influence the number of trees climbed by each liana, although we have found positive association between wrinkled bark and tendrils. Considering the individual characteristics of the host, trees with larger diameters showed higher density of lianas. In relation to the vicinity characteristics, the plots with higher rate of big trees (DBH > 30 cm) showed significant negative relation with the density of lianas. The relation was positive in plots with higher rate of trees with small crown (£ 3 m). Thus, our study showed the association between tree and vicinity characteristics with infestation and density of lianas
Doutorado
Biologia Vegetal
Mestre em Biologia Vegetal

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49

Ilstedt, Ulrik. "Soil degradation and rehabilitation in humid tropical forests (Sabah, Malaysia) /". Umeå : Swedish University of Agricultural Sciences, 2002. http://diss-epsilon.slu.se/archive/00000233/.

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Thesis (doctoral)--Swedish University of Agricultural Sciences, 2002.
Abstract inserted. Appendix reprints four papers and manuscripts co-authored with others. Includes bibliographical references. Also partially issued electronically via World Wide Web in PDF format; online version lacks appendix.

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50

Romell, Eva. "Artificial canopy gaps and the establishment of planted dipterocarp seedlings in Macaranga spp. dominated secondary tropical rain forests of Sabah, Borneo /". Umeå : Dept. of Forest Ecology and Management, Swedish University of Agricultural Sciences, 2007. http://epsilon.slu.se/10322511.pdf.

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