Tropical peatlands have some of the highest carbon densities of any ecosystem and are under enormous development pressure. This dissertation aimed to provide better estimates of the scales and trends of ecological impacts from tropical peatland deforestation and degradation across more than 7,000 hectares of both intact and disturbed peatlands in northwestern Borneo. We combined direct field sampling and airborne Light Detection And Ranging (LiDAR) data to empirically quantify forest structures and aboveground live biomass across a largely intact tropical peat dome. The observed biomass density of 217.7 ± 28.3 Mg C hectare-1 was very high, exceeding many other tropical rainforests. The canopy trees were ~65m in height, comprising 81% of the aboveground biomass. Stem density was observed to increase across the 4m elevational gradient from the dome margin to interior with decreasing stem height, crown area and crown roughness. We also developed and implemented a multi-temporal, Landsat resolution change detection algorithm for identify disturbance events and assessing forest trends in aseasonal tropical peatlands. The final map product achieved more than 92% user’s and producer’s accuracy, revealing that after more than 25 years of management and disturbances, only 40% of the area was intact forest. Using a chronosequence approach, with a space for time substitution, we then examined the temporal dynamics of peatlands and their recovery from disturbance. We observed widespread arrested succession in previously logged peatlands consistent with hydrological limits on regeneration and degraded peat quality following canopy removal. We showed that clear-cutting, selective logging and drainage could lead to different modes of regeneration and found that statistics of the Enhanced Vegetation Index and LiDAR height metrics could serve as indicators of harvesting intensity, impacts, and regeneration stage. Long-term, continuous monitoring of the hydrology and ecology of peatland can provide key insights regarding best management practices, restoration, and conservation priorities for this unique and rapidly disappearing ecosystem.

We study whether the \"China shock\'\", defined as China\'s rapid emergence in global markets, caused environmental impacts in Brazilian municipalities, since previous evidence points to effects on real wages and formal sector employment over the period of 2000 to 2010. Building on recent theoretical developments, we implement a shift-share strategy to explore variation in economic specialization between municipalities and find that China\'s direct influence on the deforestation of the Amazon and Cerrado was on average insignificant, which is supported by the literature. On the other hand, China\'s demand for commodities seemed to increase pollution-related mortality of children in mining municipalities, a result obtained by comparing it to mortality caused by other factors. However, we show that this is most likely explained by a municipality\'s degree of specialization in mining activities rather than its exposure to trade with China. We conclude that the environmental effects of the China shock on Brazilian municipalities were small, if not negligible. / Investigamos se o \"choque China\'\", definido como a rápida ascensão da China nos mercados internacionais, causou impactos ambientais em municípios brasileiros, uma vez que estudos anteriores identificaram efeitos sobre o salário real e emprego formal ao longo do período de 2000 a 2010. Orientados por avanços recentes na teoria, nós usamos uma estratégia shift-share para explorar diferenças na especialização econômica de municípios e encontramos que a influência direta da China sobre o desmatamento da Amazônia e do Cerrado foi na média insignificante, o que vai ao encontro da literatura. Por outro lado, a demanda por commodities da China pareceu elevar a mortalidade infantil causada por doenças relacionadas à poluição em municípios mineradores, um resultado obtido ao se compará-la com mortes por outras causas. Todavia, nós mostramos que a explicação mais provável é o grau de especialização do município em atividades de mineração, e não o quanto ele estava exposto ao comércio com a China. Concluímos que os impactos ambientais do choque China sobre municípios brasileiros foram pequenos, senão negligenciáveis.

Thesis (M.Phil. (Environmental law and Management)) --University of Limpopo, 2009 / Refer to document

The effects of deforestation and biomass burning in tropical dry forests (TDF) remain a little studied phenomenon. We quantified total aboveground biomass (TAGB), carbon and nutrient (N,S,Ca,P,K) loss under two separate fire severity scenarios; one early when the fuels were higher in moisture content, one later when the slash fuels were drier and then compared the loss and the regrowth of the sites. The TAGB and nutrients were measured (1993-1995) after the forest was cut, after a forest slash fire, one year after pasture establishment and, two years after the slash fire, biomass was quantified before and after a pasture fire. The treatments were based upon time from slash to burn. The low severity fires (Baja) were burned 65 days and the higher severity fires (Alta) were burned 95 days after the initial slash of TDF on ��� 3.5 ha near the Chamela Biological Research Station on the Ejido San Mateo, Jalisco, Mexico. As a result of the 1993 slash fire, TAGB declined from 118.2 to 43.6 Mg ha����� (62%) in the Baja treatment and from 134.9 to 26.8 Mg ha����� (80%) in the Alta treatment. Nutrients pools declined 57-88% with ��� 10% higher combustion of the Alta pools. In 1995, after the pasture fires, TAGB declined from 40.3 to 14.8 Mg ha����� (63%) and from 29.0 to 7.6 Mg ha����� (75%) in the Alta treatment and nutrient pools declined 57-88%. Total aboveground biomass loss from 1993-1995 was 103.4 Mg ha����� (87%) in the Baja treatment and 127.3 Mg ha����� (94%) in the Alta treatment. Carbon and nutrient losses ranged from 87-96% over the three-year study. We found little ash retention after fire, no increase in nutrient soil concentrations and, highly volatized nutrients (i.e. Ca and P) were essentially lost due to wind and water erosion on 40 to 60% slopes. Wood decomposition between fires reduced TAGB and nutrient pools by 15% in the Baja treatment and 3% in the Alta treatment. / Graduation date: 2000

This dissertation comprises four chapters. The unifying theme is the evaluation of environmental programs. Specifically, each chapter examines some facet of the impacts of protected areas. The first chapter examines the heterogeneous environmental and economic impacts of protected areas in Costa Rica. Previous studies suggest that Costa Rica's protected area system induced both reduced deforestation and alleviated poverty. We demonstrate that these environmental and social impacts were spatially heterogeneous. Importantly, the characteristics associated with the most avoided deforestation are the characteristics associated with the least poverty alleviation. In other words, the same characteristics that have limited the conservation effectiveness of protected areas may have improved the social welfare impacts of these areas. These results suggest that `win-win' efforts to protect ecosystems and alleviate poverty may be possible when policymakers are satisfied with low levels of each outcome, but tradeoffs exist when more of either outcome is desired. The second chapter explores in more detail the heterogeneous impacts of protected areas in Costa Rica and Thailand. In particular we investigate the potential for protected areas to act as a mechanism for poverty traps and use semiparametric models to identify the spatial congruence of environmental and economic outcomes. We find no evidence that protected areas trap historically poorer areas in poverty. In fact, we find that poorer areas at baseline appear to have the greatest levels of poverty reduction as a result of protection. However, we do find that the spatial characteristics associated with the most poverty alleviation are not necessarily the characteristics associated with the most avoided deforestation. We demonstrate how an understanding of these spatially heterogeneous responses to protection can be used to generate suitability maps that identify locations in which both environmental and poverty alleviation goals are most likely to be achieved. In the third chapter we address the mechanisms through which protected areas affect economic outcomes. Using recently developed quasi-experimental methods and rich biophysical and demographic data, we quantify the causal post-treatment mechanism impacts of tourism, infrastructure development and ecosystem services on poverty, due to the establishment of protected areas in Costa Rica prior to 1980. We find that nearly 50% of the poverty reduction estimated in a previous study can be attributed to tourism. In addition, although the mechanism estimates for the infrastructure and ecosystem services proxies are negligible, we argue that the results provide evidence that enhanced ecosystem services from the establishment of protected areas has likely helped to reduce poverty. The results provide additional information to policy makers that wish to enhance the future establishment of protected areas with complementary policy. The final chapter studies the economic impacts of protected areas in Bolivia. We find that municipalities with at least 10% of their area occupied by a protected area between 1992 and 2000 exhibited differentially greater levels of poverty reduction between 1992 and 2001 compared to similar municipalities unaffected by protected areas. We find that the results are robust to a number of econometric specifications, spillover analyses and a placebo study. Although the overarching results that Bolivia's protected areas were associated with poverty reduction are similar to previous studies , the underlying results are subtly, but significantly, different. In previous studies it was found that controlling for key observable covariates lead to fundamentally antithetical results compared to naive estimates. Conversely, these results indicate that naive estimates lead to an over-estimation of the poverty reducing impacts of protected areas. The results expose the heterogeneity of protected area impacts across countries and, therefore, underscore the importance of country-level impact evaluations in order to build the global knowledge base regarding the socioeconomic impacts of protected areas.

This study evaluates the effectiveness of the ecological ICMS (ICMS-e) in the Brazilian Amazon, an intragovernmental transfer for incentivizing biodiversity conservation. Tax funds are passed from state governments to municipalities in proportion to the amount of protected area within their borders; biological reserves, sustainable use areas, and indigenous lands are all considered. Econometric analysis using a fixed effects model found that the policy had little positive effect on increasing protected areas compared to the significant negative influence of poor land tenure, agricultural influences, and lack of monitoring for illegal deforestation. However, the policy may increase municipal governments' acceptance of and support for protected areas, especially if combined with institutional support.

This study examines whether aquaculture has the potential to reduce deforestation in the Peruvian Amazon. The natural resources of the Peruvian Amazon are subject to extreme pressures due to increases in subsistence farming, cattle ranching, and logging in the region. The resulting loss of biodiversity has affected the delicate soil balance that is characteristic of the Amazon, and has contributed to water pollution as well as erosion (Guerra et al. 2001). One of the highest rates of deforestation in the Amazon basin can be found at the foothills of the eastern Andes (Lepers et al. 2005), which includes the area in this study, located in the Peruvian state of Amazonas. In this part of the Amazon, deforestation is mainly caused by small-scale subsistence agriculture (Achard et al. 1998) such as that found in the communities of Condorcanqui. Fishing is an essential part of the socio-economic system that functions in the Peruvian Amazon. Fish meat is the most important source of animal protein in the Amazon, and the main generator of cash for indigenous people (McDaniel, 1997). However, freshwater Amazonian fisheries have been subject to extreme overexploitation in the past few decades (Rainforest Conservation Fund, 1999). Boats with technological equipment and large-scale capacities have threatened stocks in local rivers and oxbow lakes, which has affected the ability of small-scale, native fisherman to support themselves (Rainforest Conservation Fund, 1999). The Instituto de Investigaciones de la Amazonia Peruana (IIAP) has assisted the development of fish farming in the Condorcanqui region as a way to augment diets and decrease the ecological impact of subsistence farming. Fish farming can also be seen as a way to substitute for the loss of traditional river fishing. IIAP has become the leading governmental organization in fisheries research and aquaculture in the Peruvian Amazon, and works to provide native-species fingerlings, and educational courses to native aquaculturists. This study surveys the subsistence villages along road and river communities to determine the impact of fish farming on deforestation in the Condorcanqui region. This region is populated by small communities of indigenous Awajún and Wampí tribesmen, who practice subsistence agriculture. Data was collected from a sample of 184 families in ten different communities. Five of the villages were situated along the banks of the Nieva or Santiago river systems, while the other five were accessible by road, travelling southwest from the town of Santa Maria de Nieva. Data was collected with the assistance of the Research Institute of the Peruvian Amazon (IIAP), which provided a guide who had relations with all of the communities. All of the families in the sample practice subsistence agriculture, while 104 of the respondents supplement their agricultural crops with fish from aquaculture ponds integrated into their farmland. The participants answered a range of questions about the size of their farms, and the productivity of their land. We use a variety of regression-based approaches to determine how incorporating aquaculture into subsistence farmlands affects deforestation rates after controlling for socioeconomic and farm characteristics. Our study suggests that an extra square meter of aquaculture reduces the area deforested for crops on approximately a one for one basis. However, aquaculture should maintain its productivity for much longer than cropping, as it does not depend on soils whose fertility can be exhausted in a few years. Our simulations, based on our survey results, indicate that over time aquaculture should reduce deforestation significantly, especially in areas where soils provide only a few years of subsistence crops. These should be regarded as interesting but preliminary results. Because we used a convenience-based sampling approach, our results could be affected by selection bias. In addition, we do not have enough information to test whether selection bias in the implementation of fish farming affect our results. Therefore, these results suggest that aquaculture could be useful in limiting deforestation, but additional work should use experimental methods or more in-depth surveys to measure the effect of aquaculture on deforestation.

With an increased human impact, natural resources are under great pressure.  Deforestation is one effect of this, and the largest threat against biodiversity.. Changes in tropical habitats is a major concern for conservation biologists, due to its high biodiversity and rapid decreased area. Recently, developmental activities and habitat destruction have caused a major decline in the abundance of the terrestrial mega-fauna.This is especially evident in areas with a high human population and a rich mega-fauna as in India. The purpose of this project was to determine the land-use cover change (LUCC) in the area of Karbi Anglong, which lies in the middle of Assam, India. This was done by identifying different vegetation types from satellite images, from the years 1992, 2002 and 2011 using a remote sensing application (ERDAS) and ArcGIS. Interviews in the area werealso operated, and data about how animal use the corridors were used along with registered human-tiger conflicts. The results show that during the first period, a total of 360 km2 of the area changed vegetation type, mostly due to an increase of agricultural areas. The second largest change (79 km2) was an increase of moist mixed deciduous forest which seems to have taken over some of the semi evergreen forest’s previous area. If that is the case it is most likely an effect of selective logging from the local people, who use fire wood as fuel.All in all, there has been a great habitat loss along withfragmentation of the landscape. The conflict data shows that tigers are present between the core areas, and the interviews show that the migrations of other animals are also common.To maintain the high ecological values in Karbi Anglong, it is of great importance to maintain connectivity between core areas and stop further habitat loss and fragmentation.

<p>The construction of roads, either as an economic tool or as necessity for the implementation of other infrastructure projects is increasing in the tropical forest worldwide. However, roads are one of the main deforestation drivers in the tropics. In this study we analyzed the impact of road investments on both deforestation and jaguar habitat loss, in the Mayan Forest. As well we used these results to forecast the impact of two road investments planned in the region. Our results show that roads are the single deforestation driver in low developed areas, whether many other drivers play and important role in high developed areas. In the short term, the impact of a road in a low developed area is lower than in a road in a high developed area, which could be the result of the lag effect between road construction and forest colonization. This is consistent since roads resulted to be a significant deforestation driver for at least two decades. Roads significantly affect jaguar's habitat selection; however males showed a higher tolerance than females. From 1980 to 2000 female jaguars lost 36% of their habitat wile males lost 22%. Our forecasting of the impact of the proposed road, shows that it will promote the deforestation of approximately 16,851 has, and the jaguar habitat loss of 146,929, during the first decade; meanwhile the alternative route will have and impact of 2519 hectares and the habitat loss of 899 hectares.</p> / Dissertation

Thesis (Ph. D.)--University of California, San Diego, 2004. / Vita. Includes bibliographical references.