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1

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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2

Dumbrell, Alexander Joseph. "Impacts of selective logging on tropical-forest butterflies of Borneo." Thesis, University of York, 2006. http://etheses.whiterose.ac.uk/14076/.

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3

Tippett, Mark Donovan. "Impacts of timber harvesting on soil physical properties in wetlands." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-09292009-020154/.

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4

Ivers, Amanda J. "Modeling the hydrological impacts of logging in the Castle River watershed." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ64962.pdf.

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5

Karlsson, Daniel. "Logging impacts on catchment biogeochemistry: A review : with emphasis on northern boreal ecosystems." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-90175.

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Анотація:
The impacts of current forest management methods on surface water quality, especially in northern parts of Sweden, are largely unexplored. In this review reports linked to logging impacts on catchment biogeochemistry, (with special emphasis on boreal ecosystems) has been assessed. Logging disturbances in boreal forest catchments can change biogeochemical processes in soils by alter transpiration, soil conditions, temperature, soil microbial activities and water fluxes. Combined these changes can cause increased soil nutrient leaching to receiving waters. In the studies reviewed, dissolved organic carbon (DOC) concentrations and export generally increased after logging. Similar responses followed for phosphorous (P), but to a lesser extent for nitrogen (N). Streamflow and peakflow and the export of suspended matter (SM) can also be altered after logging. Removal of streamside vegetation may result in increased stream water temperatures and potentially affect lake water temperature, deepen the epilimnion and deplete oxygen (O2) concentrations. Increased wind exposure can resuspend sediments and potentially release bioavailable P. Affected lake water concentrations of N can be considered negligible after logging, whereas tot-P concentrations has shown to increase to an almost twofold level in some studies. The overall impact on the pelagic productivity are therefore most likely those connected to increased DOC and SM concentrations. The general impact on fish biomass can be considered insignificant. In conclusions, to improve future forest management and for further understanding concerning the biogeochemical environmental impacts that forestry might have on freshwaters, additional studies are still required.
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6

Lacerda, Andre Eduardo Biscaia de. "Ecological and genetic impacts of reduced-impact logging in the Brazilian Amazonian Forest : the case of Hymenaea courbaril L." Thesis, University of Reading, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487107.

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This study explores the present forest management systems in place and their impact on the genetic diversity and the ecology of Hymenaea courbaril in the Brazilian Amazon forest, specifically in the Tapaj6s National Forest. As part of the Dendrogene Project (EMBRAPAIDFID), this study has as its main objective to evaluate the effects of Reduced Impact Logging on the species' genetic variability and ecological processes and to predict the likely impacts in the short- and long-term. The specific objectives of this thesis are to verify the quality of the. forest inventory used in RIL at Tapaj6s National Forest, to determine impacts of harvesting on forest structure and the species' reproductive population and spatial pattern, to determine Hymenaea . courbarifs genetic diversity, spatial genetic structure, pollen flow and mating system, and assess the impact of logging on these processes, and finally to infer on the impact of logging on Hymenaea courbarifs sustainability in the long-term using the modelling software Eco-gene. The results demonstrate the critical importance of correct botanical identification for the sustainability of forest management. The assessed forest inventory was highly inaccurate in relation to botanical identification and severely underestimated trees diversity which might compromise the capacity of accurately analysing species' spatial distribution and forest timber stock. The results also show that current forest management practices have negative impacts on the H. courbaril species including a reduction in reproductive population, spatial distribution and demography. The results of logging scenarios run through Eco-gene suggest that the harvesting cycle for Hymenaea courbaril should be between 120 and 150 years in order to reach pre-logging levels. More importantly, the model suggests that current logging practice strongly affect the species' population both ecologically and genetically in the long-term. These impacts were also observed for scenarios up to 90 years unless logging intensity is very low (10 - 30%). Moreover, the model results indicate that the current practise is not economically viable as the volume to be logged in future harvests will be acutely reduced. The results of this thesis provide forest planning and management with specific scientific criteria from a heavily logged species which can help to more effectively manage not only H. courbaril, but can also be used to move toward the sustainability of other tree species in the Amazon forest.
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7

Osika, Mary Isabel. "Potential impacts of clearcut logging on lake trout (Salvelinus namaycush) reproduction in northwestern Ontario lakes." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0012/MQ33427.pdf.

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8

Barrett, Scott M. "A Computer Simulation Model for Predicting the Impacts of Log Truck Turn-Time on Timber Harvesting System Productivity." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/31170.

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A computer simulation model was developed to represent a logging contractorâ s harvesting and trucking system of wood delivery from the contractorâ s in-woods landing to the receiving mill. The Log Trucking System Simulation model (LTSS) focuses on the impacts to logging contractors as changes in truck turn times cause an imbalance between harvesting and trucking systems. The model was designed to serve as a practical tool that can illustrate the magnitude of cost and productivity changes as the delivery capacity of the contractorâ s trucking system changes. The model was used to perform incremental analyses using an example contractorâ s costs and production rates to illustrate the nature of impacts associated with changes in the contractorâ s trucking system. These analyses indicated that the primary impact of increased turn times occurs when increased delivery time decreases the number of loads per day the contractorâ s trucking system can deliver. When increased delivery times cause the trucking system to limit harvesting production, total costs per delivered ton increase. In cases where trucking significantly limits system production, total costs per delivered ton would decrease if additional trucks were added. The model allows the user to simulate a harvest with up to eight products trucked to different receiving mills. The LTSS model can be utilized without extensive data input requirements and serves as a user friendly tool for predicting cost and productivity changes in a logging contractorâ s harvesting and trucking system based on changes in truck delivery times.
Master of Science
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9

DiGennaro, James H. "An expert system for the prediction of environmental impacts of a logging operation in southeast Alaska." NSUWorks, 1992. http://nsuworks.nova.edu/gscis_etd/966.

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A computerized expert system was constructed for the prediction of environmental impacts resulting from a single clear-cut logging operation in Southeast Alaska. The knowledge base for the system was derived from the pertinent literature and from practicing professionals in the fields of forestry, wildlife, hydrology, soils, and biology. The system contains 62 if –then rules and operates on MS-DOS personal computers with at least 640 K of random access memory and a high-density disk drive. The system gathers input information about the proposed clear-cut operation by asking 22 yes or no questions to which it responds with qualitative predictions of the environmental impacts in the areas of soils, streams, fisheries, biodiversity, and wildlife. The system was validated by additional experts and prospective users to be accurate and easy to use, specific predictions are limited so however, the depth of the system may be inappropriate for intensive environmental impact assessment. The system was determined by the reviewers to be very appropriate for educational uses and broad-based initial management decision-making.
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10

Clark, Chase. "THE IMPACTS OF LOGGING WITH CURRENT AND MODIFIED BEST MANAGEMENT PRACTICES ON WATERSHED CHARACTERISTICS IN EASTERN KENTUCKY." UKnowledge, 2015. http://uknowledge.uky.edu/forestry_etds/25.

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In Kentucky, Best Management Practices (BMPs) were developed to protect the integrity of water resources during and after silvicultural operations, but their effectiveness is largely unknown. The study objectives were to (1) quantify the extent to which current BMPs minimized logging-related changes in stream water quality, channel morphology, and the content of woody debris and (2) quantify the extent to which modified BMPs influenced these characteristics. Six watersheds in eastern Kentucky were commercially logged in 2008-2009. In each watershed, one of three treatments was implemented (each replicated once). Treatment 1 (BMP) was based on current Kentucky BMPs. In treatments 2 (BMP+) and 3 (BMP++), current BMPs were modified with additional protective measures. Before the harvest, sampling sites were established in each watershed. Channel morphology and woody debris data were collected at each site in 2006 and again 2014. Data for water chemistry were retrieved from ongoing sampling records. BMP watersheds were compared to one another and to unharvested control watersheds in each year independently. Data within each individual watershed were also compared across years. The results indicate that current BMPs were effective in minimizing changes in the watershed characteristics examined here, and the benefits of modified BMPs were highly variable.
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11

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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12

McCarthy, James H. "Brook trout (Salvelinus fontinalis Mitchell) movement, habitat use, and potential impacts of forest harvesting activity in the Copper Lake Watershed, Corner Brook, Newfoundland /." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq23158.pdf.

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13

Sugar, Alissa. "The long-term impacts of clear-cut logging on insect communities in the boreal mixedwood forests of northeastern Ontario." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0018/MQ53456.pdf.

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14

Altizer, Clayton Bruce. "The wood supply system of the eastern United States an analysis of the socioeconomic impacts on local and regional value chains /." Diss., Mississippi State : Mississippi State University, 2008. http://library.msstate.edu/etd/show.asp?etd=etd-10152008-104659.

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15

Abe, Hitofumi. "Forest management impacts on growth, diversity and nutrient cycling of lowland tropical rainforest and plantations, Papua New Guinea." University of Western Australia. School of Plant Biology, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0098.

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[Truncated abstract] Globally, tropical rainforests are noted for their high biodiversity and key roles in carbon storage and influence on climate. Nevertheless, tropical deforestation in many parts of the world continues at an alarming rate. In Papua New Guinea (PNG), tropical rainforest is relatively well maintained, with about 70 % of the land area still covered by primary forest. However, PNG's native forests are coming under increasing pressure, particularly from selective logging for high quality timber. While the forests of PNG, and more broadly the entire New Guinea Island, are recognised as of high conservation and ecological significance, they remain grossly understudied with little knowledge of key ecosystem processes within lowland forests in particular. Such knowledge is urgently required if the impacts of logging and other land-use change are to be assessed and in order to develop sustainable management systems. This thesis investigated the impacts of logging on diversity and nutrient cycling in a lowland tropical rainforest growing on limestone soils in the area of the Mongi-Busiga Forest Management Agreement (FMA, which is a logging concession area), in northeastern PNG. These forests are on relatively young soils and provide a useful contrast to the majority of tropical forests. The research includes a four-year study of the recovery of diversity and structure after logging, and quantified forest structure, tree species diversity, forest biomass and productivity, and nutrient distribution and cycling. This thesis also examines the ecological sustainability of Eucalyptus deglupta plantations in Wasab, PNG as an alternative resource for timber and biomass energy. The thesis concludes with a discussion of long-term forest recovery and sustainable forest management in north-eastern PNG. Two adjacent one-hectare plots were established in lowland tropical rainforest at Mongi-Busiga FMA. One of these plots was subsequently selectively logged, one year after establishment. Before logging, the two one-hectare plots contained a total of 37 families, 70 genera and 110 tree species that were >5 cm in diameter at breast height. Mean basal area was 42.4 m2 ha-1. Two tree species, Madhuca leucodermis (Sapotaceae) and Pometia pinnata (Sapindaceae) accounted for ~60% of the total basal area. Gymnacranthera paniculata (Myristicaceae) was the most common species and accounted for 13% of individuals. ... This study concludes that the Mongi-Busiga forest has many unusual characteristics for a tropical forest, including relatively low diversity of tree species, high accumulation of P in the biomass, and N limitations, compared to other tropical rainforests. However, those extraordinary characteristics may be explained well by the underlying geology of young, marine-derived limestone. Sustainable management of the lowland tropical forests of PNG should consider the consequences of logging on nutrient cycling processes, with the possible significant removal of P from site with repeated logging, as well as the interactions between N and P in these systems. Establishment of Eucalyptus plantations on previously cleared land also has the potential to meet some of the timber and biomass energy requirements of northern PNG in ecologically sustainable manner.
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16

Schwenke, Sherri Kay. "A comparison of computer simulation techniques in depicting and communicating the visual impacts of timber harvesting in the Jefferson National Forest." Thesis, Virginia Polytechnic Institute and State University, 1994. http://hdl.handle.net/10919/94511.

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Advances in computer technology have made it possible for designers to manipulate realistic images on a computer screen. Previously, most computer generated images consisted of line drawings or distorted grid perspectives. A program known as PC/NewPerspectives, which generated distorted grid perspectives, has been in use by US Forest Service Landscape Architects who use it to determine the visual impact of a proposed harvest unit and manipulate the layout to reduce the impact. New programs in video imagery offer the opportunity to design harvest layouts on a more realistic format, which may also be used as a communication tool to relay to members of the public what the proposed alteration would look like. This study compares the two media in terms of landscape preference and acceptability of activity to determine the difference in the two media as communication tools and how this would influence their effectiveness.
M.L.A.
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17

MATEUS, CRISLENE. "Radônio como indicador de contaminação ambiental por hidrocarbonetos em fase livre." reponame:Repositório Institucional do IPEN, 2016. http://repositorio.ipen.br:8080/xmlui/handle/123456789/26610.

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Submitted by Marco Antonio Oliveira da Silva (maosilva@ipen.br) on 2016-08-26T11:02:10Z No. of bitstreams: 0
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As áreas contaminadas por NAPL (Non-Aqueous Phase-Liquids ou fase líquida não aquosa ou ainda fase livre) podem causar riscos à saúde humana e aos ecossistemas, restrições para o desenvolvimento urbano e diminuição do valor imobiliário das propriedades. Este trabalho utilizou o gás radônio como um indicador para a análise de gás subsuperficial do solo, uma vez que este gás nobre apresenta boa solubilidade em uma ampla gama de NAPL, sendo parcialmente retido na contaminação NAPL. Portanto, uma diminuição da atividade de gás radônio no solo contaminado pode ser esperada, devido à elevada capacidade de particionamento do radônio em NAPL, o que permite que o NAPL retenha uma parte do radônio anteriormente disponível nos poros do solo. O levantamento foi realizado em uma indústria abandonada, contaminada por NAPL pouco volátil, localizada na zona sudeste da cidade de São Paulo, entre junho de 2014 e maio de 2015. A concentração de radônio foi avaliada pela metodologia de detecção passiva com detectores sólidos de traços nucleares (SSNTD) tipo CR-39 em dez estações de monitoramento instaladas na área contaminada investigada e nomeadas de A até J. A média das concentrações de atividade de radônio para as oito estações de monitoramento em locais supostamente não contaminados variou de (22 ± 4) kBq.m-3 a (39 ± 4) kBq.m-3. Para as duas estações de monitoramento supostas como locais contaminados, as concentrações de radônio foram (1,4 ± 0,4) kBq.m-3 e (13 ± 9) kBq.m-3. Os resultados demonstraram que o método utilizado foi consistente com as técnicas convencionais de investigação ambiental para a maioria das estações de monitoramento em diferentes estações do ano. Resultados obtidos com CR-39 variam ao longo dos períodos de exposição, devido à sazonalidade. Não foi observada relação entre as oscilações das concentrações de atividade de radônio e o volume de chuva acumulada nos diferentes períodos de exposição dos detectores CR-39. As menores concentrações de atividade do 222Rn ocorreram nas estações de monitoramento G e H e verificou-se por espectrometria gama, que a baixa atividade não está relacionada à concentração de atividade de seu pai 226Ra na série do decaimento radioativo do 238U, reforçando a teoria de retenção do gás radônio nos locais contaminados por NAPL. Resultados da etapa de remediação comprovaram que a técnica utilizada neste trabalho foi mais eficiente que as técnicas convencionais de investigação ambiental, especialmente para as estações de monitoramento D e G na área contaminada investigada.
Dissertação (Mestrado em Tecnologia Nuclear)
IPEN/D
Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
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18

Wang, Qing. "Impacts of climate, topography, and weathering profile on vadose zone hydrology and coastal pine plantation management : a multi-scale investigation, Southeast Queensland, Australia." Queensland University of Technology, 2008. http://eprints.qut.edu.au/20657/.

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Exotic pine plantations are a major landuse within the coastal lowlands of southeast Queensland, extending from close to the shoreline to the hinterland ranges. These plantations are within a sub-tropical climatic zone, and in most years, the summers are appreciably wetter than the winters. This terrain, in general, has been highly weathered and the soils are poor in nutrients. Environmental factors such as the climate, topography and weathering profile (including soil) are found to be important controls on vadose zone hydrology, which, in turn, has a great impact on tree growth and consequently on the design of management practices. This research project takes a holistic approach to investigate the influence of these environmental factors at different scales, and is designed to fulfil the following objectives: (1) To build a spatial model of forest productivity for the entire Tuan Toolara State Forest (TTSF), southeast Queensland, by analysing the spatial patterns of many environmental variables that may have controls on soil water distribution. (2) To determine how some of these environmental factors are responsible for the development of water-logging and soil salinisation by examining in detail an area of low site index that is severely affected by these two processes. (3) To develop a model to assess the risks of water-logging spatially and temporally. A multiple regression model was constructed to predict the forest productivity (measured by the value of site index, the average dominant tree height at 25 years of age). The independent variables were derived from a digital elevation model (elevation, slope, curvature, hillshade, flow accumulation and distance to streams), γ-ray spectrometry (potassium, thorium and uranium), and interpolated rainfall. The model explained up to 60% of the variance in the site indices and produced predictive maps of site index for two species: P. elliottii Engelm. and Queensland hybrid, a P. elliottii × P. caribaea Morelet hybrid. The model also identified the lowest site index area at the northern Tuan State Forest (NTSF), likely due to a greater risk of water-logging and salinisation. The NTSF area is of low relief and, therefore, the focus has been on the vertical controls of deep weathering profile. The methodology included setting up a network of groundwater bores screened at different depths within the weathering profile, characterising the profile (mineralogy, EC, and pH) and the groundwaters within it (water levels, physico-chemical parameters, major and minor ions). It is found that water-logging is caused by perched groundwater formed on top of the ferricrete or mottled saprolite after prolonged rainfall. Localised salinisation is related to the discharge of brackish groundwater occurring within the mottled saprolite. The deep aquifer within the coarse saprolite is fresh and not responsible for salinisation, a situation that differs from many other settings in Australia. The ability of using the Soil and Water Assessment Tool (SWAT) computer model to simulate soil water balance and to assess the risks of water-logging was tested in a selected catchment in the TTSF. The model successfully simulated stream flow at 2 weirs for a period of 6 years; the achieved R2 were 0.752 and 0.858, respectively. Long-term simulation for a 30-year period showed that there are pronounced seasonal patterns in rainfall and evapotranspiration as well as in soil water. For mature plantation with slopes of 3-15%, the mean annual duration of water-logging ranged from 161 days in the humus podzols, to 110 days in the gleyed podzolic, and to 90 days in the yellow podzolics. The outcomes of this research suggest that forest management can be strongly supported by understanding the impacts of these environmental factors (e.g. climate, topography and weathering profile) on vadose zone hydrological processes; the selection of optimum approach will depend on the research objective or purpose. The models and analytical tools that were developed or tested here have the potential to be successfully applied elsewhere if the input data are available.
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19

Cardona, Miguel Angel Quimbayo. "Efeitos do manejo florestal na estrutura da avifauna na floresta Amazônica de Paragominas (Pará)." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-11032013-165828/.

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Анотація:
O Pará é o estado Amazônico mais visado pela atividade madeireira. Possui a maior gama de serrarias da Amazônia, e produze mais de 50% da madeira em tora do Brasil. A zona Leste do Estado é a responsável por 45% da produção de madeira em tora. Nessa zona se localiza o município de Paragominas, onde o 56% da população urbana depende diretamente da indústria madeireira para sua subsistência. Esta região faz parte da chamada área de endemismo Belém, cuja perda de floresta nativa é de 67,48% devido ao desmatamento. Historicamente as explorações madeireiras foram desenvolvidas com técnicas convencionais, que produzem danos tanto na floresta quanto no solo, e com impactos diretos sobre a fauna que depende da floresta. Na última década estabeleceram-se uma série de diretrizes técnicas para promover o manejo florestal em florestas de terra firme da Amazônia Brasileira, recomendadas pelo Conselho de Manejo Florestal (FSC) para todas as operações de exploração em florestas nativas. O presente trabalho teve como objetivo avaliar os efeitos do manejo florestal, incluída a exploração de impacto reduzido, em áreas exploradas em diferentes temporadas (1997, 2000, 2003, 2006 e 2009) e uma área não explorada sob a comunidade de aves, comparando a riqueza, abundância de espécies e de grupos funcionais e outros grupos ecológicos vulneráveis a distúrbios naturais e antrópicos. As aves foram usadas neste estudo devido à sua importância nos processos ecológicos da floresta como polinização, e dispersão e predação de sementes. As amostragens de campo foram feitas na temporada de seca (outubro de 2010) e chuva (abril de 2011) mediante observação direta por pontos fixos em seis transectos de 1 km de distância, com pontos marcados a cada 200 m, e distância de 150 m entre transectos, para um total de 36 pontos por área de manejo florestal. A análise das informações coletadas em campo mostra que: a) registraram-se 235 espécies entre as áreas de manejo florestal; b) existem diferenças significativas de riqueza de espécies entre a as áreas de manejo florestal e entre as temporadas de amostragem; c) a área de manejo florestal com maior riqueza de espécies e abundância de grupos funcionais foi a área explorada em 2000, contraste evidenciado com a área não explorada que teve a menor riqueza e abundâncias de grupos funcionais; d) As espécies do interior da floresta, espécies que requerem de cavidades de árvores para ninho e os grupos funcionais insetívoros (seguidores de formigas), insetívoros de sub-bosque e nectarívoros-insetívoros de sub-bosque foram os grupos cológicos mais afetados pelo manejo florestal, especialmente na área não explorada que teve atividades de pré-exploração e a área explorada em 2003 que foi afetada por distúrbios naturais antes da amostragem de campo; e) os grupos que se viram afetados pelas atividades de manejo florestal podem e devem ser usados como indicadores em programas de monitoramento durante as etapas de manejo florestal, principalmente as etapas de pré-exploração, exploração e pós-exploração, na área de manejo florestal Rio Capim.
Para is the most important state from the Amazon region in wood activities. It has the greatest sawmill of the region and produce more than 50% of the Brazilian wood. The Easte zone of the State is responsible of the 45% of wood production. In this zone is located Paragominas, a town where 56% of the urban human population depends directly on the wood industries to survive. This town is into the endemism area called Belem, whose forest loss is almost 67,48%. Historically wood explorations were made with conventional techniques that produced damages in the forest structure and into the soil, and have direct impacts on the forest fauna. In the last ten years they were established some technique guidelines to promove forest management in terra firme forests of the Brazilian Amazon, recommended by the Forest Stewardship Council (FSC) to all the exploration activities in native forests. The principal aim of this study was to assess the effects of forest management, including reduced impact logging, in areas that were logged in different seasons (1997, 2000, 2003, 2006 and 2009) and an unlogged area, on the community of birds, comparing richness, species and guilds abundance, and other ecological groups that are vulneravel to the natural and antropic disturbances. Birds were used because of its importance in forest ecological process like pollination, and seed dispersion and predation. Fieldwork was made in dry season (October 2010) and rain season (abril 2011) by direct observations in pointcounts into 1 km transects; six transects were sampled with pointcounts at each 200 m with a total of 36 pointcounts per area. Information analysis demonstrate that: a) were registered 235 species into the all six forest management areas; b) there were significative differences in species richness between forest management areas and sampled seasons; c) species richness and guild abundances had their major value in the area logged in 2000, contrasting with the unlogged area that had lower values in this items; d) species of the forest interior, cavity nesters, and understorey ant follower insectivores, insectivores and nectarivores were the most affected ecological groups by the forest management, specially in the unlogged area that had pre-logged activities and the area logged in 2003 that was affected by natural disturbances before fieldwork; e) Ecological groups named above that were the most affected by the forest management could and should be used as indicators in monitoring programs during the forest management steps, principally pre-logging, logging and pós-loggingin the Rio Capim Forest Management Area.
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20

Inada, Tomoya. "Evaluation of the sustainability of a logging system consisting of selective logging and line planting in Indonesia." Kyoto University, 2015. http://hdl.handle.net/2433/199361.

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Анотація:
Kyoto University (京都大学)
0048
新制・課程博士
博士(農学)
甲第19037号
農博第2115号
新制||農||1031(附属図書館)
学位論文||H27||N4919(農学部図書室)
31988
京都大学大学院農学研究科森林科学専攻
(主査)教授 神﨑 護, 教授 北島 薫, 教授 北山 兼弘
学位規則第4条第1項該当
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21

McDonald, Heather Noel. "The impact of logging on aquatic salamander communities." [Johnson City, Tenn. : East Tennessee State University], 2001. http://etd-submit.etsu.edu/etd/theses/available/etd-0711101-121822/unrestricted/mcdonaldh0730.pdf.

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Анотація:
Thesis (M.S.)--East Tennessee State University, 2001.
Title from electronic submission form. ETSU ETD database URN: etd-0711101-121822 Includes bibliographical references. Also available via Internet at the UMI web site.
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22

Castro, Tito Nunes de. "Modelagem do crescimento e produção aplicado ao manejo florestal na Amazônia brasileira." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-05072016-144318/.

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Анотація:
A floresta Amazônica possui um papel ambiental, social e econômico importante para a região, para o país e para o mundo. Dessa forma, técnicas de exploração que visam a diminuição dos impactos causados à floresta são essenciais. Com isso, o objetivo dessa tese é comparar a Exploração de Impacto Reduzido com a Exploração Convencional na Amazônia brasileira através de modelos empíricos de árvore individual de crescimento e produção. O experimento foi instalado na fazenda Agrossete, localizada em Paragominas - PA. Em 1993, três áreas dessa fazenda foram selecionadas para exploração. Na primeira área, 105 hectares foram explorados através da Exploração de Impacto Reduzido. Na segunda área, 75 hectares foram submetidos à Exploração Convencional. E, por fim, a terceira área foi mantida como área testemunha. A coleta de dados de diâmetro à altura do peito e a identificação das espécies dentro de uma parcela de 24,5 hectares, instalada aleatoriamente em cada área, foi realizada nos anos de 1993 (antes da colheita), 1994 (seis meses depois da colheita), 1995, 1996, 1998, 2000, 2003, 2006 e 2009. Dessa forma, as três áreas foram comparadas através do ajuste de um modelo de incremento diamétrico, considerando que efeito estocástico podia assumir outras quatro distribuições além da distribuição normal, de um modelo de probabilidade de mortalidade e de um modelo de probabilidade de recrutamento. O comportamento do incremento diamétrico indicou que as áreas que foram submetidas a exploração possuem o mesmo comportamento em quase todos os grupos de espécies, com exceção do grupo de espécies intermediárias. Os indivíduos que são submetidos a exploração possuem um maior crescimento em diâmetros quando comparados com área que não sofreu exploração. Além disso, assumir o efeito estocástico com distribuição Weibull melhorou o ajuste dos modelos. Em relação à probabilidade de mortalidade, novamente as áreas que sofreram exploração possuem comportamento semelhante quanto à mortalidade, mas diferente da área que não foi explorada, sendo que os indivíduos localizados nas áreas exploradas possuem uma maior probabilidade de morte em relação aos presentes na área não explorada. Os modelos de probabilidade de recrutamento indicaram diferença apenas entre as áreas exploradas e a área controle. Sendo que, as áreas exploradas apresentaram uma maior taxa de recrumento em comparação a área não explorada. Portanto, o comportamento individual das árvores após a exploração é o mesmo na Exploração Convencional e na Exploração de Impacto Reduzido.
The Amazon forest has an important environmental, social and economic role for the region, the country and the world. Thus, logging techniques aimed the mitigation of impacts caused to the forest are essential. Hence, the purpose of this thesis is to compare the Reduced Impact Logging to the Conventional Logging in the Brazilian Amazon through individual tree empirical yield and growth models. In 1993, three areas of this farm had selected for logging. In the first area, 105 hectares were harvested by Reduced Impact Logging. In the second area, 75 hectares underwent Conventional Logging. Finally, the third area was kept as a control area. The diameter at breast height and the species identification were collect inside a 24.5 hectares plot, located randomly in each area. The data were collect in 1993 (before harvest), 1994 (six months after the harvest ), 1995, 1996, 1998, 2000, 2003, 2006 and 2009. Therefore, the three areas were compared by adjusting a diameter increment model, whereas stochastic effect may take five different distributions, a survival probability model, and a recruitment probabil- ity model. The behavior of the diameter increment indicated the areas were subject to logging have the same behavior in almost every successional groups of species, except in the interme- diate species group. Individuals who are undergoing harvest have a greater diameter growth compared with the area that has not logged. Also, assume the stochastic effect with Weibull distribution improve the fit of models. Regarding the probability of survival, logged areas have similar behavior, but different from another area that has not harvest. The individuals located in the logged areas have an increased mortality rates. Recruitment probability models indicated a difference only between the logged area with not logged area. The logging areas presented a bigger recruitment rates than not logged area. Then, the individual behavior of trees after logging is the same for Reduced-Impact Logging and Conventional Logging.
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23

Tay, John. "Economic assessment of reduced impact logging in Sabah, Malaysia." Thesis, Bangor University, 1999. https://research.bangor.ac.uk/portal/en/theses/economic-assessment-of-reduced-impact-logging-in-sabah-malaysia(f0662486-ee81-46d6-95cc-3542b4337268).html.

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Анотація:
The economics of two selective logging systems were investigated in Sabah, Malaysia. Both logging systems employed chainsaws and bulldozers to extract timber. Reduced impact logging (RIL) differed from conventional logging (CL) in that it included comprehensive preharvest planning, pre-harvest climber cutting, stock mapping, tree marking, directional felling, and a set of environmentally-friendly skidding guidelines. RIL has been widely recognised as the logging technique to achieve sustainable utilisation of tropical forest. The main objective of this research was to compare the immediate and long term (60 years) economic costs and benefits of RIL with those of conventional logging (CL) practice in terms of timber and nontimber values. The suit of non-timber benefits included carbon, soil, non-timber forest product namely, rattan, water and wildlife values. The study was carried out in Sabah, Malaysia within the Sabah Foundation forest concession. The primary source of data for this research came from a commercial project that was initiated between Innoprise Corporation Sdn Bhd (Malaysia) and the New England Electric Supplies (USA). The RIL project was aimed at reducing logging damage using RIL, hence, increase carbon sequestration potential in forest biomass. The economic analysis comprised two parts, namely (i) an assessment of the logging impacts on the ecological parameters, and (ii) carrying out an economic cost-benefit analysis. Primary data were collected for the timber, carbon, soil values and rattan values using a system of rectangular plots. The water and wildlife values were based on secondary data from published information. To determine the timber harvest for the second cut, a forest growth model (DIPSIM) was adopted for this purpose. Similarly, the potential future carbon in the logged forest was projected using a carbon recovery model (C-REC). The valuation of the timber and non-timber values was based on the market price and opportunity costs techniques. Future costs and benefits were discounted at rates between 2% and 10 % using standard method except where costs and benefits were not derived on annual basis. The findings of this study showed that using RIL to harvest timber had reduced logging damage on the forest vegetation and soils by 50 % compared with CL techniques. Timber production per area logged was comparable with conventionally logged forest, but differed significantly when compared on per management unit basis. There were fewer skid trails and log landings in RIL forest. In addition, soil disturbances was lower on skid trails and log landings, hence, the negative effects of off-site sedimentation was reduced. The lower disturbance in the RIL forest resulted in higher timber stock for timber and non-timber product such as rattan. The timber yield for the second harvest from RIL forest was also higher compared with CL forest. However, RIL was more expensive than CL techniques under some assumptions and constraints. Non-timber benefits other than carbon in the cost-benefit analysis were relatively unimportant. Carbon prices were variable, ranging from negative prices, through prices quite comparable with other results, to very high prices. The study concluded with justifications to relax the RIL harvesting guidelines that were pertinent to the area left unlogged in RIL. There was also a case for exploring alternative logging technologies such as helicopter logging to harvest the unlogged area. These airborne technologies were conceivably costlier than ground based logging system, but the international community could share this burden in a united stand to strive towards sustainable utilisation of tropical forests.
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24

Galante, Michael Victor. "Climate change mitigation through reduced-impact logging : a framework approach." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/20439.

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Анотація:
The implementation of reduced-impact logging (RIL) in Sabah is recognised in the literature as an activity to reduce the environmental impact of timber harvest activities, thus reducing carbon entering the atmosphere. With the adoption of the Paris Agreement in 2015, modalities for its application as a project-based activity under the Climate Convention have yet to be developed. Investigations on both, its potential to reduce carbon from being released into the atmosphere in Sabah, specifically, and its modalities as a project-based activity under the Climate Convention in Malaysia, broadly, are warranted. This thesis addresses a set of research questions related to modalities for its inclusion under the Climate Convention, temporal and spatial responses of the forest after its implementation, to the investigation of activity-specific modalities, and their effectiveness, and its associated finance under the Climate Convention in Malaysia. The improvement of the forest activities under the Climate Convention are conceptualised through the Hierarchy of Production Forest Management (HoPFM), i.e., a modular framework defining the progression of the forest industry through demonstrable benefits. The conceptual framework begins from the basic legal and regulatory frameworks that govern forest management activities, towards sustainable forest management as the ideology of the Framework, designed to recognise both local, and global, approaches to forest management, while highlighting the need for balanced considerations of environmental, social and economic values. Through the Framework, the components of RIL in Sabah are discussed, relative to the modalities of the Climate Convention. Since he inception of the GIZ programme to improve forest management systems in the Deramakot forest reserve, there has been limited research on its recovery after RIL activities. Data on aboveground alive tree biomass and deadwood necromass was collected, and tested against 'harvest intensity', and 'time since harvest', to assess the temporal and spatial variability of forest responses, both within diameter classes, and major functional species classes of 'dipterocarp' and 'non-dipterocarp'. It was identified that 'harvest intensity' was found to be affecting forest recovery, relative to 'time since harvest', which was similarly identified for 'dipterocarp' species, relative to 'non-dipterocarp', respectively. The few significant changes detected indicate that long-term periods of analysis are required to identify consistent trends over-time. Since the mandate of the RIL policy in Sabah, conventional harvest activities are no longer eligible to be practiced in commercial production reserves. Therefore, to measure changes in carbon between the practices under the Climate Convention, a baseline needs to be developed, where conventional harvest activities were historically, the only form of harvest practice. An analysis of the literature was undertaken to estimate the difference between the practices, whereby broad impact classes of ‘infrastructure created’, and ‘harvest damage’, were identified. In its application, the ‘crediting’ approach is applied, whereby a benchmark is set, counterfactually, to estimate carbon that would be released without RIL activities. A number of carbon reductions are withheld from issuance into the market, to create a buffer between actually and potential issuance. The approach is conservative, to account for changes in policy and project-based circumstances, which may impact the number of carbon reductions issued in a project timeframe. RIL is currently implemented in the commercial production reserves, however it its effectiveness to reduce carbon from entering the atmosphere under the Climate Convention in Malaysia is unclear. Representing extremes along a range of anthropogenic disturbance through RIL activities, data from RIL activities was collected in a lower montaine forest harvested once, and a lowland forest, harvested multiple times. Both areas were tested against the carbon baseline, to represent conventional harvest practices in Sabah. The estimates were comparable to literature values, with RIL activities found to reduce carbon from entering the atmosphere. The variability in the accumulation of carbon stocks of aboveground alive tree biomass was identified as an important consideration in the trends observed. The condition of the forest at the time of harvest, i.e., primary or severely degraded logged-over forest, was found to impact carbon stocks immediately after harvest and the rate of carbon accumulation over time. The variability of the result supports the concept of conservativeness, as advocated for project-based activities, under the Climate Convention. As a signatory Party, Malaysia is developing the necessary institutional infrastructure to facilitate project-based activities under the Climate Convention. Investigating RIL as a nationally appropriate mitigation action is undertaken, where distinctions are made between its integration at the national level, and its implementation at the sub-national level. Drawing on experiences from Sabah, implementing RIL as a project-based activity under the Climate Convention is broadly applicable to all States in Malaysia, whereby monitoring, reporting and verification at the sub-national level may be implemented through the existing domestic forest certification standard in Malaysia. At the current price of carbon over a 35-year harvest cycle, RIL is estimated to be approximately at the break-even price for its implementation in Sabah. Relative to the cost of restoring severely degraded forests harvested through conventional practices in Sabah, implementing RIL is financially viable. The knowledge gained by investigating RIL as a sub-national approach may be useful to assist Malaysia to meet their intended national emission reduction targets under the Climate Convention. This thesis aims to improve our knowledge of the application of RIL in logged-over forest of Sabah, and its applicability as a project-based activity under the Climate Convention in Malaysia. Several research questions were raised, to contextualise the modalities of RIL in Sabah and the institutional framework in Malaysia, relative to the architecture of the Climate Convention. It highlights the need for a systematic approach to gather observations on forest carbon dynamics and their integration into larger carbon accounting frameworks, to improve our understanding of the potential of RIL to contribute to reduce carbon emissions into the atmosphere from the forest sector.
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25

Naves, Rafaela Pereira. "Dinâmica da diversidade de florestas manejadas através da abordagem de ajuste e seleção de modelos para distribuição de abundância entre espécies." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-21032018-155252/.

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Анотація:
As florestas na Amazônia tem sido exploradas para a provisão de madeira. A exploração era feita sem planejamento das atividades (Exploração Convencional ou EC), resultando em grandes áreas de florestas degradadas. A partir da década de 90, foram estabelecidas técnicas para minimizar os danos da exploração à vegetação remanescente, visando ciclos sequenciais de corte, sem prejuízo à produção, através da Exploração de Impacto Reduzido (EIR). Embora muito tenha sido discutido sobre o quão mais eficiente a EIR seja em relação a EC, ainda existem lacunas, principalmente acerca da organização e manutenção da diversidade dessas áreas. A exploração é, de maneira muito resumida, o corte de algumas árvores de interesse comercial e a morte acidental de outras árvores que não as de interesse, pela queda e arraste das toras, construção das estradas e dos pátios de estocagem. As clareiras formadas, em geral, são maiores que as que ocorrem naturalmente na floresta. Essas clareiras são ocupadas por espécies de rápido crescimento, potencialmente mudando a organização da comunidade. Assim, são necessárias abordagens para detectar e então caracterizar quais os impactos que a exploração tem na diversidade de comunidades arbóreas. É importante ressaltar que muitas decisões sobre a sustentabilidade do manejo são tomadas considerando como essas comunidades respondem a distúrbios. Diante do apresentado, esta tese teve como objetivo analisar a dinâmica da diversidade de florestas submetidas à exploração florestal. A distribuição de abundância entre espécies (DAE) é uma abordagem paramétrica para caracterização de comunidades, baseada em um dos poucos padrões que se mantem em todas as comunidades: muitas espécies raras e poucas espécies abundantes, sendo também o reflexo de como as espécies partilham recursos. Distúrbios mudam a identidade das espécies dominantes, podendo ser refletido em alterações nos parâmetros e/ou curvas da DAE. Nós analisamos a DAE de áreas submetidas ao manejo florestal (EIR e EC) e uma área Controle, antes do manejo e ao longo de 16 anos em Paragominas, Pará, Brasil. Antes da exploração, em 1993, foram estabelecidas três parcelas permanentes, onde os indivíduos arbóreos com DAP ≥ 25 cm foram cadastrados. Indivíduos menores (DAP ≥ 10 cm) foram mensurados em sub-parcelas. Após essa primeira medição, foi conduzida exploração em duas parcelas (EIR e EC) e a terceira parcela foi mantida como Controle. As parcelas foram medidas novamente em 1994, 1998, 2000, 2006 e 2009. Para testar se a DAE muda devido ao manejo, usamos a distribuição Poisson Lognormal (PLN) para descrever cada ano e cada tratamento. Para detectar mudanças na similaridade, em termos de composição de espécies e abundância relativa de cada espécie, nós usamos o parâmetro de correlação da PLN bivariada para comparar a comunidade antes da exploração com os outros anos. Ao contrário do esperado, não foram encontradas mudanças estatisticamente relevantes nos parâmetros da DAE ao longo do tempo em nenhum dos três tratamentos. Entretanto o parâmetro de correlação diminui para a comunidade com o menor critério de inclusão de DAP, nas últimas medições das áreas exploradas. Nós também analisamos a DAE dessas mesmas áreas considerando como medida de abundância a área basal de cada espécie. Não foram encontradas mudanças relvantes na DAE, apenas diminuição do parâmetro de correlação. Embora o manejo tenha resultado na diminuição de até 22% dos indivíduos e 27% da área basal, ele não é imediatamente detectado na DAE pois as mortes acidentais são a maioria no manejo. Para cada árvore explorada, em média 19 árvores com DAP ≥ 10 cm são mortas acidentalmente. Essa morte acidental é de certa forma independente da espécie, assim todas as espécies tem suas abundâncias diminuídas. A distribuição PLN considera os efeitos da amostragem através do processo Poisson, então mesmo que a porcentagem de indivíduos mortos fosse maior, dificilmente seria detectável na DAE. No entanto, a diminuição do parâmetro de correlação ao longo do tempo nas áreas exploradas é devido ao aumento da abundância e da área basal de espécies de rápido crescimento como as do gênero Cecropia. A DAE da Ilha de Barro Colorado (BCI), Panamá, também foi analisada (28 anos de medições, DAP ≥ 1 cm). Nós dividimos o conjunto de dados em quatro critérios de inclusão de DAP (1, 10, 25 e 45 cm). Visto que a área não é submetida a grandes distúrbios e, como era esperado, não foram encontradas mudanças relevantes nem na DAE nem na identidade das espécies dominantes. Muitos indivíduos morreram durante esse período, devido a elevada mortalidade, comum para árvores pequenas (DAP < 10 cm), e outra grande parcela da comunidade não atingiu os critérios de DAP que geralmente são amostrados (10, 25 e 45 cm). Mesmo os indivíduos considerados ingressantes, de acordo com esses critérios, já estavam presentes na parcela na primeira medição, apenas eram menores que esses critérios. Diante do apresentado, um distúrbio pode demorar décadas para aparecer nas classes de DAP que geralmente são amostradas, por exemplo DAP ≥ 10 cm. Assim, reiteramos que efeito ou falta de efeito de distúrbios na diversidade de comunidades arbóreas deve ser interpretado com muita cautela.
Amazon tropical forests in Brazil have been exploited for the provisioning of timber, mainly using conventional logging (CL) practices. Little operational planning has been considered and, as a result, large forest areas in the Amazon have become highly degraded over time. Since the 1990\'s, reduced impact logging (RIL) has been adopted as a means of reducing the damage caused by timber exploitation and of establishing more sustainable practices, trying to make sequential logging cycles possible. Much has been discussed about the higher efficiency of RIL or CL, but there are still important knowledge gaps, mainly regarding tree diversity and forest functioning in logged areas. The logging of commercial species and the accidental death of non-targeted trees may alter environmental conditions, leading to higher abundance of some species and to the reduction of others, thus modifying forest structure and diversity. These changes promoted by exploitation have a signature in the structure of the remaining community and tracking them at the community level is still a great challenge, but important decisions are mainly taken considering tree diversity. The development of tools is crucial to quantify the effects of disturbance and to predict its consequence over communities. The main goal of this thesis was to analyze the temporal dynamics of tree diversity in the context of forest management. Species abundance distribution models (SAD) are a parametric approach, based on the most strong pattern in community ecology: few species have high abundance and rarity is the rule. It is also independent of sampling size and related to how species share resources. Species dominance change as a result of disturbances, and these changes may be detectable by changes on the parameters and/or curves of the SAD. We used inventory data from three permanent plots established in 1993 in Paragominas, Pará, Brazil. All the trees with Diameter at Breast Height (DBH) ≥ 25 cm were determined and measured and smaller individuals were measured within subplots (DBH ≥ 10 cm). After this first survey, we harvested two plots using different techniques (RIL and CL) and a third plot was kept as Control. The plots were surveyed again in 1994, 1998, 2000, 2006 and 2009. To test if it is possible to detect changes in the SAD due to logging we used the Poisson Lognormal distribution (PLN) to describe the data from each year. To detect changes in species similarity, we compared species composition and abundance over time, using the correlation parameter of the bivariate PLN. We compared the same plots in 1993 (before exploitation) and in the years that followed. We observed no relevant changes in SAD, but only small changes in the correlation parameter in the last surveys. We also analyzed species\' basal area distribution, and found no statistically relevant changes apart from small changes in the correlation parameter in harvested areas. After exploitation, we observed a reduction of as much as 22 % of the number of trees and 27% of the basal area, and mortality was mainly attributed to the accidental death of non-targeted trees. For each tree harvested, an average 19 trees died accidentally. Because of the dominant role of these random accidental deaths, the signature of management operations could not be detected immediately after logging, using SAD or the correlation parameter. Since SAD models consider sampling effects (Poisson process), any disturbance which causes the random death of trees may not be detected in the short run. However, the start of small changes could be noticed within a couple of decades. The relative abundance of some species has been altered in exploited forests, which was detected by changes in the correlation parameter. Pioneer species of the genus Cecropia have become the most abundant trees in the last survey, considering DBH ≥ 10 cm. We also evaluated species abundance distribution in the Barro Colorado Island, Panama (28 years, DBH ≥ 1 cm). We established four different inclusion criteria (DBH 1, 10, 25 and 45). The area was not subject to major disturbances and, as expected, we observed no relevant changes in the SAD during this period. A large number of individuals died during this period, due to the high mortality common to small trees (DBH ≥ 10 cm), and many others have not reached the used inclusion criteria (10, 25 and 45 cm). Using these inclusion criteria, we showed that the community recruited during this period was already present in the forest in the first survey, but those trees just did not reach the size to be measured. Therefore, a recent disturbance may take decades to be detected within the DBH classes usually sampled. We highlight the role of time scale in the interpretation of tree diversity dynamics.
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26

Castro, Tito Nunes de. "Comparação de diferentes formas de colheita florestal na Amazônia brasileira através da modelagem da produção e do crescimento." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-16042012-165725/.

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A exploração madeireira na floresta Amazônica tem sido bastante discutida nos últimos anos. Novas técnicas de exploração que visam a redução do impacto proveniente da exploração têm sido criadas almejando o uso sustentável da floresta. Dessa forma, essa dissertação tem o objetivo de avaliar o período de recuperação da floresta tropical amazônica depois da Exploração de Impacto Reduzido e da Exploração Convencional, comparando-as. O experimento foi instalado na fazenda Agrossete em Paragominas, estado do Pará, no ano de 1993 com a exploração madeireira da área. Foram alocadas parcelas na área de exploração convencional, exploração de impacto reduzido e na área de preservação permanente que totalizam em cada área 24,5 hectares. Os dados de diâmetro a altura do peito, nome da espécie e características qualitativas foram coletados antes da exploração no ano de 1993, e depois da exploração nos anos de 1994, 1995, 1996, 1998, 2000, 2003, 2006 e 2009 nas árvores de interesse comercial com diâmetro a altura do peito (DAP) maior que 10 cm e nas árvores sem interesse comercial com DAP maior que 25 cm. Foi realizada a modelagem, a nível de povoamento, da produção a fim de determinar o incremento em volume das explorações, assim como, a modelagem da distribuição diamétrica através de matrizes de transição após a exploração, definindo o padrão temporal de seu crescimento. A modelagem da produção indicou uma rápida recuperação do volume da floresta para ambas as explorações, em contrapartida, considerando apenas o volume comercial passível de corte, a área de Exploração de Impacto Reduzido não recuperou dentro do ciclo de corte e a área de Exploração Convencional não alcançará os mesmo níveis que possuía antes da exploração em um médio prazo. Na modelagem da distribuição dos diâmetros, a Exploração de Impacto Reduzido alcançou a mesma estrutura diamétrica após o período do ciclo de corte, diferentemente da área de Exploração Convencional, sendo que as classes diamétricas com os maiores diâmetros são favorecidas na Exploração de Impacto Reduzido, diferentemente do que ocorre na Exploração Convencional.
Logging in Amazon forest has been much discussed in recent years. New logging techniques aiming the reduction of impacts from logging has been developed trying to reach the sustainable use of forest resources. In this way, this project aims to asses and compare the recuperation time of Amazon rainforest after the Reduced Impact Logging and the Conventional Logging. The experiment was installed in Agrossete farm, localized in Paragominas - PA, in 1993 through of loggings area. Plots, with 24.5 ha each, were allocated in the Reduced Impact Logging area, Conventional Logging area and Permanent Preservation area. Diameter at breast height (DBH), specie name and qualitative characteristics were collected for commercial interest trees with DBH bigger than 10 cm and for trees without commercial interest with DBH bigger than 25 cm, before the logging in 1993 and after the logging in 1994, 1995, 1996, 1998, 2000, 2003, 2006, 2009. The volume increment and the diameter distribution, was shaped for the purpose of determine the forests yield and growth after the logging, so, defining temporal pattern of growth. The yield modeling showed a fast recovery of the forest volume for both logging system, however, considering only the commercial volume able to be harvest, the Reduced Impact Logging did not recover the volume in a 30 years period (cutting cycle) and the Conventional Logging will not recover the volume in a medium term. Modeling the diameter distribution, the Reduced Impact Logging reached the same diameter structure after the period of the cutting cycle, unlike Conventional Logging, and the diameter classes with larger diameters are favored in the Reduced Impact Logging, unlike what happens in conventional exploration
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27

Ibrahim, Shamsudin. "Impact of logging on peat swamp forest vegetation in peninsular Malaysia." Thesis, Bangor University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.396273.

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28

Achet, Shiva Hari. "An integrated approach to modeling : the impact of timber harvest on streamflow : a GIS based hydrologic model /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/5545.

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29

Peters, Susan Heidi. "The impact of small mammals on natural regeneration of white spruce after logging." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0008/MQ59864.pdf.

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30

Chaves, Didier Willandia. "Reduced-impact logging and hunting patterns in the southwestern Brazilian Amazon implications for wildlife /." [Gainesville, Fla.] : University of Florida, 2009. http://purl.fcla.edu/fcla/etd/UFE0041350.

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31

Silva, Edson José Vidal da. "Dinâmica de florestas manejadas e sob exploração convencional na Amazônia Oriental." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/18/18139/tde-12022016-113125/.

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Esta tese compara as dinâmicas de uma floresta explorada com exploração de impacto reduzido (EIR) com outra explorada convencionalmente (EC) numa propriedade denominada Fazenda Agrosete (3º S, 50º W), em Paragominas, no nordeste do Estado do Pará. Os estudos foram realizados numa área de 210 ha, dos quais 75 ha foram explorados convencionalmente, 105 ha foram explorados com exploração de impacto reduzido e 30 ha não explorados (testemunha). A área foi explorada em 1993 e monitorada até 2000. A avaliação da dinâmica das espécies madeireiras nesses três tratamentos foi feita em 10 clareiras selecionadas em cada tratamento. A análise dos efeitos dos tratamentos silviculturais sobre a regeneração de valor madeireiro foi feita em 60 clareiras selecionadas aleatoriamente em cada tratamento. A análise da diversidade de espécies arbóreas foi feita numa área de 5,25 ha delimitada em cada tipo de exploração. E, finalmente, para analisar a dinâmica de espécies arbóreas estabeleceram-se 49 parcelas de 0,5 ha em cada tratamento. Os resultados demonstraram que: i) considerando a regeneração abaixo de 10 cm de DAP não existiram diferenças significativas na dinâmica da regeneração entre as clareiras de exploração de impacto reduzido e as de exploração convencional; ii) os tratamentos silviculturais causaram efeitos positivos sobre o crescimento de espécies de valor comercial presente nas clareiras crescendo de 75% a 115% a mais do que as não tratadas; iii) considerando as espécies arbóreas acima de 10 cm de DAP, a diversidade de espécies reduziu com a colheita e tem apresentado uma boa recuperação, inclusive na área explorada de madeira convencional; iv) a mortalidade de árvores foi menor e o recrutamento foi maior no tratamento de exploração de impacto reduzido em comparação com os tratamentos de exploração convencional e com a testemunha; v) a taxa anual de mortalidade na área de exploração convencional foi 70% superior ao da área com exploração de impacto reduzido; e vi) o crescimento das árvores no tratamento exploração de impacto reduzido foi 5,5 vezes maior do que o crescimento no tratamento de exploração convencional. Esses resultados demonstram que a exploração de impacto reduzido reduz bastante os efeitos negativos sobre a diversidade de espécies, além de promover o crescimento das árvores. Dessa maneira, as florestas exploradas com técnicas de exploração de impacto reduzido se recuperarão num período relativamente menor do que as florestas exploradas convencionalmente, ao mesmo tempo em que estarão mantendo a conservação da biodiversidade florestal. Nossa conclusão é que a exploração de impacto reduzido pode ser uma alternativa ao modelo de exploração atualmente praticado na Amazônia.
This thesis compares the dynamics of forest harvested using reducing impact logging (RIL) and conventional logging forest (CL) at the property known as Fazenda Agrosete (3º S, 50º W), in Paragominas, in the north-east of the State of Pará. The studies were carried out in an area of 210 ha, of which 75 ha were conventional logging, 105 ha were logged using reducing impact logging (RIL) and 30 ha was an unlogged control. The area was harvested in 1993 and monitored until 2000. The evaluation of the dynamics of timber species in these three treatments was carried out in 10 gaps selected in each treatment. The analysis of the effect of silvicultural treatments on regeneration of timber value was done in 60 randomly selected gaps were for each species. The analysis of tree species diversity was done in an area of 5.25 ha delimited for each type of logging. And, finally, to analyse the dynamics of tree species 49 lots, each measuring 0.5 ha were established in each treatment. The results demonstrate that: i) considering regeneration below 10 cm DBH there were no significant differences in regeneration dynamics between the gaps in the reducing impact logging (RIL) area and those in the conventional logging area; ii) the silvicultural treatments caused positive effects on growth of commercially valuable species present in the gaps; grew 75% a 115% more than non-managed regeneration; iii) considering tree species above 10 cm DBH, species diversity was reduced with harvest and has shown good recovery, including in the conventional harvested area; iv) tree mortality was lower and recruitment was higher in the reducing impact logging (RIL) treatment in comparison with conventional logging and witness treatments; v) the annual mortality rate in the conventional logging area was 70% higher than that of the area under reducing impact logging (RIL); and vi) growth of trees in the management treatment was 5.5 times higher than growth under the conventional logging treatment. These results demonstrate that reducing impact logging (RIL) considerably reduces negative effects on species diversity, besides promoting tree growth. In this way, forests logged using reducing impact logging (RIL) techniques will recover in a relatively shorter period than forests that are conventional logging, while at the same time maintaining forest biodiversity. Our conclusion is that reducing impact logging (RIL) can be an alternative to the logging model currently practised in Amazon.
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32

Anwar, Syaiful. "The impact of different logging treatments on streamflow and suspended sediment concentration in Central Kalimantan, Indonesia." Thesis, University of Edinburgh, 2001. http://hdl.handle.net/1842/14747.

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Reduced Impact Logging (RIL) introduced in some places has been reported to improve harvesting efficiency and environmental impact e.g. better design of skidtrails, less waste wood, reduces forest damage and cost. In this study, the effect of RIL on hydrological aspects was examined to assess its impact on direct runoff, streamflow, suspended sediment and unit hydrograph of the catchment, comparing RIL with conventional logging (CL) and an unlogged (UL) control. Compared to the control, the ratio of water yield to rainfall increased by about 53% with RIL and 98% with CL treatment after a period of 3 to 4 months following logging. Direct runoff with RIL remained similar to the control but increased by about 140% with CL treatment. Compared to CL treatment, the mean maximum suspended sediment concentration (Cmax.) levels can be reduced by more than six times and the daily suspended sediment load (S) by almost half if RIL treatment is implemented. The ratio of Cmax and S under UL, RIL and CL treatments are about 1 : 5 : 32 and 1 : 6 : 11 respectively. The main cause of erosion and sedimentation was soil damage due to compaction by harvesting machinery and soil cover reduction. RIL treatment is capable of reducing the runoff coefficient about half than that of CL: mean runoff coefficients for UL, RIL, and CL treatments are 0.027, 0.045 and 0.095 respectively. Unit hydrograph models for the two replications of each treatment showed shape consistency (e.g. time to peak is shorter with UL than RIL and CL treatments) and could be used to predict direct runoff from the related catchments. Finally, the study showed that supervision of harvesting - including planning and post logging treatment has an important role in reducing logging impact on hydrological behaviour.
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33

Arnhem, Eric. "Eco-ethological response of great apes and other rainforest mammals to selective logging in Cameroon." Doctoral thesis, Universite Libre de Bruxelles, 2008. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210369.

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

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

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

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

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

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

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

/

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

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

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

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

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

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

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

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34

McCarthy, Megan Elaine. "The impact of forest harvesting on forest floor coleoptera of balsam fir forests of Western Newfoundland /." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1996. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq23159.pdf.

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35

Martana, Kadim. "Modelling socio-economic effects of implementing reduced-impact logging : a case study of Berau District East Kalimantan Province Indonesia." Thesis, University of Canterbury. School of Forestry, 2013. http://hdl.handle.net/10092/9434.

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Reduced-impact logging (RIL) was identified as a measure, complementary to other identified measures, which can contribute to Indonesia reducing emissions from forestry and forest degradation (REDD+). In this light, the research was aimed to investigate the economy-wide impact of implementing RIL on the economy, which was studied at the district level. For this purpose, an expert opinion survey method was integrated with Berau computable general equilibrium (CGE) model. The expert opinion survey was utilised to: (i) generate information and confirm the impact of implementing RIL on logging costs, and (ii) obtain an estimate of the incentive required by logging companies to maintain the practice of RIL. Results of this approach provided input to the Berau CGE model. In addition, multiple ways of data gathering were employed to develop the dataset required for the general equilibrium analysis. Simulation results suggest that the economic impact of implementing RIL policy is negative but small on the Berau economy compared to a situation where the RIL is not implemented. Worker households (particularly agricultural worker households) are worse off and non-agricultural households are better off. Furthermore, providing compensation, which was simulated as a logging output- based subsidy, can improve the Berau economy, although to only a lesser degree. The RIL policy causes a significant negative impact on logging output which further leads to output reduction in forest-based and pulp & paper industries. The policy implementation, however, simulates production increase in other agricultural activities, notably in oil palm plantation. Furthermore, results simulations with the logging output-based subsidy suggest the magnitude of economic impacts is reduced from what would otherwise occur in the scenario of implementing RIL only (no subsidy is provided). The RIL policy also seems to result in ̳unexpected‘ emissions leakage indicated by increases in output of some agricultural-based activities such as oil palm plantation, other estate crops, and food crops. Increase in emissions is also expected to occur outside the Berau District stimulated by the increase in the District‘s import of timber.
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36

Sartori, Roberto Scorsatto. "Avaliação econômica de uma operação de impacto reduzido em uma propriedade privada no estado amazônico de Rondônia." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-15052012-092443/.

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As florestas desempenham funções econômicas, ecológicas e sociais insubstituíveis, e muito se especula e experimenta sobre a possibilidade desses recursos poderem simultaneamente gerar renda e serem conservados por meio de técnicas de exploração de impacto reduzido. No Brasil, um novo marco regulatório foi estabelecido em 2006 para ordenar o manejo de florestas públicas e os processos de concessões dessas áreas para o setor privado. Todavia, ainda não se observa redução significativa na dinâmica predatória e ilegal de exploração dessas florestas naturais, principalmente em biomas como o Amazônico. Este trabalho descreve o processo de estabelecimento e execução de um plano de manejo, os gargalos do processo e a avaliação econômica de um projeto no estado de Rondônia. A avaliação utilizou a simulação Monte Carlo e indicadores financeiros para avaliar, sob condições de aleatoriedade, o desempenho econômico do referido projeto. Conceitos baseados no valor presente líquido e na taxa interna de retorno foram aplicados para avaliar esse desempenho. Os resultados mostraram que a exploração de impacto reduzido e a venda de toras para serrarias no estado de Rondônia é viável técnica e economicamente. Em uma área de 560ha de manejo anuais e com um investimento de aproximadamente R$ 800.000,00 no início do projeto é possível obter lucro anual de R$ 150.000,00 a R$ 300.000,00 já a partir do terceiro ano. A simulação Monte Carlo mostrou que há 90% de probabilidade que o projeto tenha uma TIR maior que 13,80%.
Forests have economic, ecological and social irreplaceable functions, and much is speculated and investigated about the possibility of these resources simultaneously generate income and be preserved by means of reduced impact logging. In Brazil, a new regulatory framework was established in 2006 to regulate the management of public forests and the processes of concessions in these areas to the private sector. Since then no significant reduction in the dynamics of predatory and illegal exploitation of these natural forests has been observed yet, particularly in biomes like the Amazon. This paper describes the process of submitting and implementing a forest management plan, refers to obstacles of the process and presents an economic evaluation of a real project in Rondônia state. The economic evaluation used Monte Carlo simulation and financial indicators to assess, under conditions of randomness, the economic performance of the project. Concepts based on net present value and internal rate were applied to evaluate the economic performance. Results have shown that reduced-impact logging and the sale of logs to local sawmills in the state of Rondônia is technically and economically feasible. Harvests in an area of 560 hectares and an initial investment of approximately $ 800,000.00 at the beginning of the project resulted in net revenues in between R$ 150.000,00 and R$ 300,000.00 at the beginning of the third year. Monte Carlo simulation showed that there is a 90% probability that the project has an IRR greater than 13.80%.
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37

Sontag, Vanessa Erler. "Alterações na legislação brasileira de manejo florestal e seus efeitos na distribuição espacial e polinização de espécies madeireiras amazônicas." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-13032018-155634/.

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Conhecer o comportamento espacial e demográfico e a dinâmica genética das espécies madeireiras e manter uma distância entre as árvores que permita sua reprodução é essencial para o desenvolvimento de procedimentos de manejo que visem a conservação das espécies e garantia de estoques futuros de madeira. No entanto, quando uma área é explorada para fins madeireiros, as árvores remanescentes podem não ficar a uma distância viável a polinização. A legislação brasileira atual limita a exploração de espécies com baixa densidade de ocorrência e define alguns critérios para a escolha das árvores remanescentes, porém, eles levam em consideração apenas o número de indivíduos e não os fatores ecológicos e genéticos das espécies além de serem os mesmos aplicados a toda Amazônia. O objetivo deste trabalho foi analisar o comportamento espacial de três espécies madeireiras, a Manilkara huberi, a Hymenaea courbaril e o Handroanthus serratifolius, em quatro áreas de estudo na Amazônia brasileira a partir de inventários de empresas florestais e verificar a implicação das últimas mudanças ocorridas na legislação no processo de polinização dessas espécies. O trabalho foi dividido em duas partes. A primeira verificou se essas três espécies possuem o mesmo padrão espacial em diferentes regiões da Amazônia e discutiu a questão da raridade presente na legislação. Foi calculada a densidade e a matriz do vizinho mais próximo para todos os indivíduos antes do corte das três espécies em cada área de estudo e as distâncias plotadas em um gráfico quantil-quantil. Os resultados mostraram que a Manilkara huberi é uma espécie que pode ser encontrada em alta ou baixa densidade e em agregados ou não dependendo da região de ocorrência, diferente do Handroanthus serratifolius que apresenta uma densidade e padrão de distribuição semelhante independente da região de ocorrência. A Hymenaea courbaril permeia entre essas duas situações. Notou-se uma semelhança na distribuição das espécies entre as áreas próximas. A segunda parte analisou as consequências da alteração da legislação na distância entre as árvores remanescentes das três espécies e verificou se essa distância era viável para o processo de polinização. Foi simulado o corte a partir de cenários legislativos, em que apenas o diâmetro mínimo de corte (DMC) foi alterado. Os resultados mostraram que houve uma diminuição na distância entre árvores. A diminuição favoreceu o processo de polinização visto que os polinizadores precisam percorrer menores distâncias na busca por alimento. A legislação tem tomado um caminho mais conservativo, porém há muito o que ser desenvolvido, visto que cada espécie possui sua própria ecologia reprodutiva mas são manejadas da mesma forma.
The information about the spatial and demographic behavior and the genetic dynamic of timber species and maintaining a distance between trees that allows their reproduction is essential for the development of management procedures to conserve species and guarantee future wood stocks. However, when an area is harvested for timber purposes, the remaining trees may not stay at a feasible distance for pollination. Current Brazilian legislation limits the exploitation of low-density species and defines some criteria for choosing the remaining trees. However, they take into account only the number of individuals and not the ecology and genetic aspects of the species. Besides, the same criteria are applied to the entire Amazon. The aim of this study was to analyze the spatial behavior of three timber species, Manilkara huberi, Hymenaea courbaril and Handroanthus serratifolius, in four study areas in the Brazilian Amazon Forest. Companies inventories were used to verify the implication of the latest changes in the Brazilian legislation on the pollination process of these species. The study was divided into two parts. The first one verified if these three species have the same spatial pattern in different regions of the Amazon and discussed the rarity issue in the legislation. The density and the nearest neighbor distance matrix were calculated for all individuals before cutting for the three species in each study area and the distances were plotted on a quantile-quantile plot. The results showed that Manilkara huberi can be found in high or low density and aggregated or not depending on the region of occurrence. On the other hand, other than Handroanthus serratifolius populations present similar densities and distribution patterns despite region of occurrence. Hymenaea courbaril permeates between these two situations. The distribution of this species among nearby areas showed similarity. The second part of this work analyzed the consequences of changes in Brazilian forest management legislation on the distance between the remaining trees of the three species and verified whether this distance was feasible for the pollination process. The cutting was simulated based on two legislative scenarios, in which only the minimum cut diameter (MCD) was changed. The results showed that there was a decrease in the distance between trees due to the increase of the density of remaining individuals. The distance decrease favored the pollination process, since pollinators need to travel shorter distances searching for food. Brazilian forest legislation has taken a more conservative path, but there is still much to be developed, since each species has its own reproductive ecology, even so are managed the same way.
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38

Herselman, Charlene. "From ‘logging capital’ to ‘tourism phenomenon’ : the impact of literary tourism on Forks, WA., United States of America." Diss., University of Pretoria, 2014. http://hdl.handle.net/2263/45925.

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Literary tourism refers to any travel inspired by literature. This dissertation considers literary tourism from the perspective of a contemporary literary tourism attraction. It investigates the origins of literary tourism both in the historical context as well as in academic writing as interdisciplinary research between geography and literature. The current state of literary tourism research is also considered and the main research themes at present are identified, that is, authenticity and who the literary tourists are. This study also considers what the future might hold for literary tourism by looking at popular contemporary examples, including the works of J.K. Rowling, G.R.R. Martin, J.R.R. Tolkien, Dan Brown, Stieg Larsson and L.J. Smith. In this context, literary tourism’s reciprocal relationship with film tourism is unpacked. This dissertation then moves on to discuss the main focus of this investigation. A mere decade ago, the world was unaware of a book series called The Twilight Saga by Stephenie Meyer. Yet in a few short years, the literary tourism associated with this series has turned a small town in northwest Washington State into a tourism phenomenon. This study considers the development, extent and impact of literary tourism on this town, called Forks. It also considers other literary and film tourism sites associated with The Twilight Saga to show the vast range of the impact literature can have on tourism.
Dissertation (MHCS)--University of Pretoria, 2014.
tm2015
Historical and Heritage Studies
MHCS
Unrestricted
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39

Md, Noor Nur Supardi. "The impact of logging on the community of palms (Arecaceae) in the lowland dipterocarp forest of Pasoh, Peninsular Malaysia." Thesis, University of Reading, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298516.

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40

Vinson, Christina C. "Impact of selective logging on inbreeding and gene flow in two Amazonian timber species with contrasting ecological and reproductive characteristics." Thesis, University of Oxford, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.510253.

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41

Taufik, Agustinus Winanto. "Study on the impact of selective logging on the abundance of anurans in the rain forests of Central Kalimantan, Indonesia." Thesis, University of Edinburgh, 1998. http://hdl.handle.net/1842/27507.

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Anurans (amphibians) have also been identified as potentially valuable indicators of some environmental changes. The small home ranges and relatively limited dispersal ability may render amphibians useful for monitoring the effects of local environmental pertubations. In addition, their moist permeable eggs and skin also make them good 'bioindicators' of environmental stress. Given both the important roles and functions of amphibians in forest ecosystems and the significant impacts of logging on forest ecosystems, an understanding of amphibians in relation to forestry practices is required. Relatively few studies have focused on the impact of logging on amphibians especially in the tropics. Those that have been undertaken have related mainly to temperate regions where the logging is usually clear felling and they have concentrated either on single species or on single genera. Therefore, this study will attempt to address this gap of knowledge about the impacts of selective logging on the abundance of anurans in the rain forests of Kalimantan, Indonesia. The study was undertaken from November 1994 to July 1996 at Camp 92, Central Kalimantan. Three sampling methods were used in this study e.g. pitfall traps, searched quadrats and night riparian transects. The results demonstrate that logging had a significant effects on the abundance of anurans and anuran species composition. Logging had a strong influence on vegetation cover, which in turn affects the temperature and humidity. Logging also affects the physical characteristic of the streams especially the bottom substrates. Logging also affects the physical characteristic of the streams and abundance of anurans. The challenge in research for future researchers of amphibian-forestry relationships is to identify realistic timber harvest prescriptions that best maintain those components of the forest's biological legacy that are essential for healthy amphibian populations and forest ecosystem as a whole.
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42

Brummel, Kenneth R. "The impact of group selection silviculture on timber harvesting cost in the southern Appalachians." Thesis, Virginia Tech, 1992. http://hdl.handle.net/10919/42747.

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National Forest timber management in the southern Appalachians is changing from traditional even-aged management and clearcutting to uneven-aged management and group selection silviculture. Group selection, with its small 1/2-to-2-acre patch cuts widely dispersed throughout a timber stand, has the potential to substantially increase timber harvesting costs over traditional clearcutting. This could exacerbate the below-cost timber sale issue. The objective of this study was to assess the impact of groups election silviculture on timber harvest productivity and cost in hardwood stands of the southern Appalachians. This was accomplished by collecting and analyzing field production and cost data from typical Appalachian loggers operating on group-selection timber sales. Three logging systems were chosen for the study: (1) cable yarder ,(skyline) system; (2) feller-buncher/cable skidder system; and (3) motor-manual chainsaw felling/cable skidding system. At least one full week of time-study production data was collected at each location. cost information was obtained from the cooperating loggers' records, as well as historic production and cost data from previous clearcut sales for comparison purposes. study results show that production was reduced and unit cost increased for all three logging systems when operating on group-selection timber sales as compared to clearcutting. unit cost per ton for the cable yarder system was $40.18, a 29 percent increase over their previous average clearcutting cost. The fellerbuncher/cable skidder system unit cost per ton was $14.79, a 19 percent increase over this system's average clearcutting cost. The chainsaw felling/cable skidder system cost of $16.15 per ton was 33 percent above their normal clearcutting cost. A large increase in delays and unproductive time as a result of specific group-selection timber sale characteristics appears to be the major cause of reduced logging productivity and increased costs.
Master of Science
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43

Muhamad, Harbe. "Geophysical studies in the western part of the Siljan Ring Impact Crater." Doctoral thesis, Uppsala universitet, Geofysik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-312022.

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This thesis utilizes several geophysical methods to study the Siljan Ring impact structure, focusing on the western part of the structure. This thesis, and the three papers upon which it is based, reports on attempts to delineate the Paleozoic rocks at depth within the annular ring graben and characterize their structure. In addition, the nature of the basement, which underlies these sedimentary rocks is investigated. Papers I and III focus on analysis of the down-hole logging and borehole core data. As well as the acquisition, processing and interpretation of 2D high-resolution reflection seismic data from the Mora area. The borehole log responses were compared with the core lithology from the Mora 001 borehole and information from two other cores (Mora VM 2 and Mora MV 3) in order to interpret the logs. The logs reveal significant changes in the lithology between boreholes, indicating a very high level of structural complexity, which is attributed to impact tectonics. In addition, the log data revealed a high sonic velocity contrast between the Silurian and Ordovician successions and a higher apparent temperature gradient than in the northern part of the structure. The interpretation of the high-resolution 2D seismic data suggest that the Mora area has been significantly affected by the impact. Several potential faults were identified in the area and interpreted to be post depositional and related to the impact. In paper II, a 2D seismic profile from the Orsa area (12 km) located in the northwestern part of the Siljan Ring was re-processed. To compliment this seismic line, first break traveltime tomography results, vintage seismic OPAB profiles, new and pre-existing gravity data, aeromagnetic data and the bedrock geological map were used to present a geological model along the Orsa profile. Reprocessing of the seismic data resulted in improved stacked and migrated sections and better imaging of the top of the crystalline basement than the original processing. Integrated interpretation of the seismic profiles suggests that the area has been significantly affected by faulting and that the depth to the basement varies greatly along the different profiles.
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44

Harrison, Carolynn A. "The impact of fire and clear cut logging on the vegetation dynamics of black spruce peatlands in the Manitoba Model Forest." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ45055.pdf.

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45

Kachamba, Daud Jones. "Impact of harvesting machinery on soil physical parameters : evaluation of ProFor model in three main forestry regions of South Africa /." Link to the online version, 2007. http://hdl.handle.net/10019/648.

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46

Savill-Smith, Carol A. "Introducing information and communications technology (ICT) into the secondary school classroom : pupils' experiences of data logging and its impact on their learning." Thesis, Brunel University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.394792.

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47

Reis, Cristiano Rodrigues. "Mapeamento das restri??es operacionais e ambientais numa ?rea de Floresta Amaz?nica por meio do escaneamento laser aerotransportado." UFVJM, 2018. http://acervo.ufvjm.edu.br/jspui/handle/1/1789.

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Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq)
Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)
Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG)
Como defendido na explora??o de impacto reduzido, o planejamento ? fundamental para o manejo sustent?vel de florestas tropicais. Novas tecnologias, como o LiDAR, t?m permitido a constru??o de mapas e obten??o de estimativas que auxiliam tanto no planejamento quanto nas etapas de explora??o e monitoramento do impacto. Com o intuito de reunir os diversos produtos do escaneamento laser aerotransportado (ALS) dispersos na literatura e ?teis no manejo florestal, o objetivo deste trabalho foi apresentar uma sequ?ncia metodol?gica para determinar e monitorar as restri??es ambientais e operacionais em uma ?rea sob manejo na Amaz?nia. A ?rea de estudo encontra-se na fazenda Cauaxi, munic?pio de Paragominas, estado do Par?. Foram sobrevoados 1214 hectares de Floresta Amaz?nica submetidas a manejo de impacto reduzido. Foram gerados os modelos digitais de terreno (MDT), hidrol?gicos e topogr?ficos. A vegeta??o foi mapeada por meio dos modelos de densidade relativa (MDR), de biomassa, de localiza??o de ?rvores dominantes e codominantes, de clareiras e gerado o mapa da infraestrutura existente. Por fim, a estrutura vertical da floresta foi analisada pela descri??o do perfil vertical do dossel. A resolu??o do MDT foi de 1 metro e foi poss?vel observar a varia??o da eleva??o local e os divisores de ?gua. A densidade de drenagem foi de 1,7 km/km? e as ?reas de preserva??o permanente (APP) de cursos d??gua e nascentes somaram 137,7 ha. Mapas pouco utilizados como os de microbacias e dist?ncias vertical e horizontal poderiam ser considerados na divis?o da ?rea em unidades de produ??o anual e na delimita??o de APP, respectivamente. A declividade variou de 0 a 30?, n?o apresentando APP por declividade, caracter?stica de um relevo predominantemente suave ondulado. As ?reas com restri??o ao trator skidder n?o ultrapassaram 1 km? e, as restritas aos caminh?es carregados somaram 1,9 km?. A densidade de estradas na ?rea foi de 23,42 m.ha-1 e o n?mero de p?tios por hectare foi de 0,04. A ?rea total impactada pela abertura de estradas, trilhas e p?tios foi de 30,77 hectares, correspondendo ? 2,54% da ?rea total. Foi poss?vel observar menores valores de biomassa nas unidades de produ??o anual j? exploradas. O mesmo ocorreu entre os valores de porcentagem de clareiras. O valor de biomassa m?dio, considerando pixels de 50 m?, foi de 35,5 kg. Os menores valores dos par?metros de forma e escala da fun??o Weibull para o sub-bosque mostraram rela??o com as ?reas impactadas pela abertura de infraestrutura, sendo uma alternativa ao MDR no monitoramento do impacto. J? o par?metro de escala para o estrato da copa teve rela??o com o modelo de m?ximo dossel, indicando a localiza??o das ?rvores emergentes. Foi poss?vel mapear de maneira precisa as ?reas com restri??es ambientais e operacionais a partir do ALS, bem como, obter outros produtos interessantes para o manejo florestal. Este trabalho apresentou um roteiro metodol?gico para a inser??o do ALS no planejamento de todas as etapas do manejo florestal.
Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2018.
The reduced impact logging refers to the forest planning as a critical step to the sustainable tropical forest management. New technologies, such as LiDAR, have made possible to obtain maps and estimates which help on the planning, exploitation and impact monitoring phases. In order to gather the useful products of airborne laser scanning (ALS) in forest management, the objective of this work was to present a methodological sequence to determine and monitor the environmental and operational constraints in an area under management in the Amazon. The overflown area is located at the Cauaxi farm, municipality of Paragominas, state of Par?, Brazil. The ALS covered 1214 hectares of amazon forest submitted to reduced impact logging. Then, models such as digital terrain model (DTM), hydrological and topographic were extracted. Furthermore, the vegetation was mapped through models of relative density (MDR), biomass, localization of dominant and codominant trees, and clearing and map of the existing infrastructure. Finally, the forest vertical structure was analyzed by the description of the canopy height profile. The 1meter resolution DTM allowed to observe the variation of elevation and water dividers. The drainage density was 1.7 km/km? and the permanent preservation areas (PPA) related to water courses and springs comprised 137.7 ha. Underused maps such as micro-basins and vertical and horizontal distances could be considered in the division of the area into annual production units and in the PPA delimitation, respectively. The slope ranged from 0 to 30 ? and did not present PPA by slope, characteristic of a predominantly soft wavy relief. The areas restricted to the skidder tractor does not exceed 1 km?, and those restricted to loaded trucks generated a total of 1.9 km?. The density of roads inside the area was 23.42 m.ha-1 and the number of the storage yards per hectare was 0.04. The area impacted by the opening of roads, trails and yards was 30.77 hectares, corresponding to 2.54% of the total area. It was possible to observe lower values of biomass in the annual production units already exploited. The same occurred with the percentage values of clearings. The average biomass value considering pixels of 50 m? was 35.5 kg. The lower values of shape and scale parameters of the Weibull function for the understory were related to the areas impacted by the infrastructure opening. The maps obtained with the Weibull parameters for understory can be an alternative to the RDM on the impact monitoring. The canopy scale parameter was related to the tall canopy model, indicating the location of the emergent ones. It was possible to accurately map the areas with environmental and operational restrictions from the ALS, as well as obtaining other interesting products for forest management. This work presents a methodological guide for the insertion of ALS in the planning of all stages of forest management.
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48

Cloutier, Dominic. "Conservation genetics of exploited Amazonian forest tree species and the impact of selective logging on inbreeding and gene dispersal in a population of Carapa guianensis." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=102969.

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The Amazon region is one of the richest areas on the planet in terms of its biodiversity and natural resources. The large scale harvesting of trees in this region is a relatively new activity, and it is uncertain whether the exploitation of timber species will result in depletion of forest genetic resources. To examine this, I have assessed levels of inbreeding, gene flow, and genetic diversity in populations of Amazonian forest trees undergoing logging. Because of their high variability within populations, microsatellite genetic markers were chosen for the study, and it was verified through an initial sampling experiment that this class of markers is sufficiently stable within somatic tissue of large and long-lived trees such that population studies could be undertaken with them. By sampling adult trees and seed progenies at several microsatellite loci, high levels of gene flow and low levels of inbreeding were found within populations of Sextonia rubra and Carapa guianensis, two important insect-pollinated Amazonian forest tree species. Comparing seed progeny collected before versus after selective logging of a population of Carapa guianensis, no measurable evidence was found that that the population genetic dynamics is impacted by logging. In particular, levels of inbreeding, gene flow, and population substructure were the same before and after logging. Comparing different populations distributed over the Amazon basin, a phylogeographical structure in the chloroplast DNA of Carapa guianensis that corresponds to major tributaries of the Amazon river was discovered, suggesting that seed dispersal through rivers may contribute to genetic connectivity among populations. Overall, the results of this thesis suggest that the large effective population sizes, the high levels of gene flow, and the low levels of inbreeding in exploited Amazonian tree populations may allow them to counteract potential negative genetic impacts of selective logging, at least at the levels of harvesting carried out during this study, and for the Carapa guianensis population investigated.
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49

Konopik, Oliver [Verfasser], and Ingolf [Gutachter] Steffan-Dewenter. "The impact of logging and conversion to oil palm plantation on Bornean stream-dependent frogs and their role as meso-predators / Oliver Konopik. Gutachter: Ingolf Steffan-Dewenter." Würzburg : Universität Würzburg, 2015. http://d-nb.info/1109750358/34.

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50

Darrigo, Maria Rosa 1978. "Ecologia populacional de sete espécies arbóreas em áreas de exploração seletiva de madeira de impacto reduzido na Amazônia Central." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315904.

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Orientadores: Flavio Antonio Maës dos Santos, Eduardo Martins Venticinque
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Exploração de madeira realizada sob manejo de impacto reduzido tem sido considerada uma forma de auxiliar a refrear o desmatamento na Amazônia. No entanto, poucos dados estão disponíveis para verificar o impacto dessa atividade sobre a floresta, e assim, avaliar o potencial das áreas sob manejo para conservação de habitats. Nessa tese investigamos o impacto da exploração seletiva de madeira na regeneração e dinâmica de cinco espécies comerciais (Goupia glabra, Manilkara huberi, Manilkara bidentata, Minquartia guianensis e Zygia racemosa) e duas não exploradas (Pouteria anomala e Protium hebetatum). Instalamos parcelas permanentes em áreas sem exploração e em talhões com diferentes idades de regeneração após a exploração (2, 5 e 12 anos). Verificamos ocorrência de efeitos da exploração de madeira sobre fatores abióticos, e a relação desses com a regeneração de indivíduos pequenos (10 a 100cm de altura, Capítulo I). Através de modelos e simulações, avaliamos a sustentabilidade dos parâmetros (como ciclo de corte e intensidade de extração) atualmente utilizados nos principais planos de manejo propostos para a Amazônia (Capítulo II). Por fim, avaliamos se variações nas condições luminosas, encontradas nas áreas exploradas, podem alterar a interação herbívoro-planta, resultando em efeitos sobre a mortalidade de jovens (Capítulo III). Nossos resultados apontam para maior luminosidade e fertilidade do solo nas áreas exploradas. Em função do aumento da luz, verificamos também aumento no crescimento, mas que deve persistir apenas até aproximadamente 5 anos após a exploração. Já o aumento da fertilidade do solo encontrado nas áreas exploradas não contribuiu para aumento do crescimento. As taxas de mortalidade foram maiores nas áreas exploradas, mesmo em locais com 12 anos de regeneração. Tais variações nas taxas vitais foram verificadas para espécies comerciais e não comerciais indicando que as alterações ambientais proporcionadas pela exploração afetam também a regeneração das espécies sem valor madeireiro. Encontramos maiores taxas de herbivoria e crescimento nas clareiras e nas áreas exploradas, em função da maior luminosidade. No entanto, enquanto nas áreas controle a herbivoria foi maior nas clareiras que no sub-bosque, respondendo, então, a um aumento de luminosidade, nas áreas exploradas não ocorreu diferença, indicando que as taxas de herbivoria são independentes da intensidade luminosa. A herbivoria foi um fator importante como condicionante da mortalidade dos jovens, mas aparentemente essa interação está influenciando a mortalidade de maneira análoga entre áreas exploradas e controle. Portanto, essa interação não deve ser responsável pela maior mortalidade de jovens encontrada nas áreas exploradas (Capítulo I). As taxas assintóticas de crescimento (ls) encontrados nas áreas controle indicam estabilidade ou crescimento populacional, dependendo da espécie. Já nas áreas exploradas encontramos ls que indicam declínio das populações, com exceção de P. hebetatum, espécie não explorada. Deste modo, concluímos que a exploração de madeira não é sustentável, mesmo considerando as melhores técnicas de extração praticadas no Brasil. Aparentemente, a mortalidade de jovens (verificada no Capítulo I) e a intensidade de corte são fatores determinantes das taxas de crescimento populacional encontradas nas áreas exploradas
Abstract: Reduced-impact logging systems have been considered one way to diminish deforestation rate in Amazonia. However, we do not have enough knowledge about the effects of such systems, due to a lack of data about regeneration and dynamics of tree species. In this thesis we investigated the impact of selective logging on regeneration and dynamics of five commercial species (Goupia glabra, Manilkara huberi, Manilkara bidentata, Minquartia guianensis and Zygia racemosa) and two non-exploited species (Pouteria anomala and Protium hebetatum). We investigated effects of selective logging on the abiotic factors as well as in the regeneration of small individuals (10 to 100cm tall, Chapter I). Through models and simulations, we verified the sustainability of the parameters currently used in the major management plans, proposed for logging activities in Amazon (Chapter II). Finally, we assessed whether variations in light conditions found in the exploited areas could change herbivore-plant interactions, resulting in effects on the mortality of small individuals and their regeneration. Our results pointed to higher light and soil fertility in the exploited areas. We also found an increment in growth rate, due to canopy opening, which should last five years after exploitation. The higher soil fertility found in the exploited areas did not increase the growth rate. The mortality rate was higher in the exploited areas, even in those after 12 year regeneration period. The variation in the vital rates was verified in both exploited and non exploited species, which indicates that logging environmental alteration might also affect the regeneration of noncommercial species. We found higher herbivory and growth rates in gaps and in exploited areas, due to higher light intensity. However, in the control areas the herbivory was higher in the gaps than in the understory, thus responding to the increase in light conditions. In the exploited areas, the herbivore rate was the same in gaps and understory. Herbivory was an important factor conditioning the mortality of small individuals, but this interaction has equally influenced mortality in exploited and non-exploited areas. Therefore, this interaction should not be considered a cause of higher small individuals mortality rates found in the exploited areas. Population growth rates indicate stability or population growth of the tree species in the control areas, but in the exploited ones we found a shrinking population (exception to P. hebetatum, non-exploited species). We concluded that the reduced impact selective logging is not sufficient to warrant sustainability. Higher mortality of small individuals and logging intensity seems to be an important factor that contributes to the lower population growth rates verified in the exploited areas
Doutorado
Ecologia
Doutor em Ecologia
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