UMD Theses and Dissertations
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Item SPATIAL EFFECTS OF LOCAL GOVERNANCE INSTITUTIONS ON ILLEGAL DEFORESTATION IN DEVELOPING COUNTRIES(2019) Kraus Elsin, Yoanna; Lichtenberg, Erik; Agricultural and Resource Economics; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Deforestation worldwide is a major concern. In developing countries, it is a merciless and devastating reality. My thesis addresses how local governance institutions' strength influences this phenomenon, focusing on the Colombian Andes. The theoretical analysis examines spatial patterns of illegal deforestation when enforcement is costly, and costs rise with distance from governmental centers. Those spatial patterns depend on the interaction between transportation costs incurred by farmers growing crops on deforested land and enforcement costs incurred by government officials conducting on-the-ground monitoring of deforestation. Areas closer to governmental centers can be monitored effectively and are thus less subject to illegal deforestation. Illegal deforestation is, therefore, more likely in areas where monitoring costs are high, but farmers' transportation costs are not. The calibration exercise then shows, that in this context, patches of deforestation might arise within the forest, causing unwanted forest fragmentation. Based on these results I study empirically, first, if the effect of access difficulty on deforestation may be non-monotonic in accessibility, causing forest fragmentation; and second, if this fragmentation is more likely to occur when enforcement is more costly. I approach this question in two manners: (1) using a cubic function of access difficulty interacted with measures of enforcement capacity and (2) non-parametrically using indicators for discrete ranges of access difficulty, again interacted with measures of enforcement capacity. I construct for this purpose a panel data set for the Colombian Andes from a variety of sources. Data on deforestation comes from satellite imaging at a 30mx30m resolution in two periods (2000-2005) and (2005-2010), this data was matched with biophysical variables such as, altitude, slope, precipitation, soil type, and roads using geographical information systems (GIS), as well as with socioeconomic variables which vary by municipality and time. The regressions show a significant non-monotonic effect of access difficulty on deforestation. The evidence shows that deforestation probability first decreases with access difficulty, and it then increases in remoter places. This evidences forest fragmentation as one moves away from roads. Moreover, this pattern is affected by the fiscal performance index (a proxy for enforcement capacity) of the municipalities, showing that municipalities with lower enforcement capacity have a higher probability to present illegal deforestation at remote places. This research adds to the deforestation literature, by studying the spatial reach of governance capacity and how it affects deforestation patterns. The findings highlight the importance of taking enforcement and monitoring costs as well as their spatial variation into account when designing land-use policies and defining the institutional arrangements, funding and monitoring processes to implement them.Item Changes in Amazon Forest Structure from Land-Use Fires: Integrating Satellite Remote Sensing and Ecosystem Modeling(2008-11-17) Morton, Douglas; DeFries, Ruth S; Geography; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Fire is the dominant method of deforestation and agricultural maintenance in Amazonia, and these land-use fires frequently escape their intended boundaries and burn into adjacent forests. Initial understory fires may increase forest flammability, thereby creating a positive fire feedback and the potential for long-term changes in Amazon forest structure. The four studies in this dissertation describe the development and integration of satellite remote sensing and ecosystem modeling approaches to characterize land-use fires and their consequences in southern Amazon forests. The dissertation contributes three new methods: use of the local frequency of satellite-based active fire detections to distinguish between deforestation and maintenance fires, use of satellite data time series to identify canopy damage from understory fires, and development of a height-structured fire sub-model in Ecosystem Demography, an advanced ecosystem model, to evaluate the impacts of a positive fire feedback on forest structure and composition. Conclusions from the dissertation demonstrate that the expansion of mechanized agricultural production in southern Amazonia increased the frequency and duration of fire use compared to less intensive methods of deforestation for pasture. Based on this increase in the frequency of land-use fires, fire emissions from current deforestation may be higher than estimated for previous decades. Canopy damage from understory fires was widespread in both dry and wet years, suggesting that drought conditions may not be necessary to burn extensive areas of southern Amazon forests. Understory fires were five times more common in previously-burned than unburned forest, providing satellite-based evidence for a positive fire feedback in southern Amazonia. The impact of this positive fire feedback on forest structure and composition was assessed using the Ecosystem Demography model. Scenarios of continued understory fires under current climate conditions show the potential to trap forests in a fire-prone structure dominated by early-successional trees, similar to secondary forests, reducing net carbon storage by 20-46% within 100 years. In summary, satellite and model-based results from the dissertation demonstrate that fire-damaged forests are an extensive and long-term component of the frontier landscape in southern Amazonia and suggest that a positive fire feedback could maintain long-term changes in forest structure and composition in the region.Item The Economics of Fallow: Evidence from the Eastern Amazon(2007-08-01) Klemick, Heather; Lopez, Ramon; Agricultural and Resource Economics; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)With tropical deforestation a major contributor to greenhouse gas emissions and biodiversity loss, the land use decisions of small-scale farmers at the forest margins have important implications for the global environment. In some tropical forests, such as the Eastern Brazilian Amazon, farmers practice a shifting cultivation system that maintains large amounts of land under forest fallow. I examine whether local benefits of fallowing such as soil restoration, erosion mitigation and hydrological regulation are of sufficient value to farmers to stem the expansion of permanent cropland at the expense of forest. I quantify the value of ecosystem services provided by fallow to agriculture and test whether local forest externalities are economically significant, using farm survey and GIS data from the Eastern Amazon. I estimate a production function to determine the contribution of on-farm and upstream fallow to income, using an instrumental variables approach to address endogeneity. I find that on-farm and upstream fallow are both associated with higher farm income. This result both confirms the agronomic evidence that fallow boosts yields and suggests that fallow provides positive hydrological externalities to downstream farms. I also examine whether farmers respond strategically to their neighbors' land use, taking advantage of ecosystem services provided by upstream farms. I use a spatial econometric model to estimate the effect of upstream farms' fallow on downstream land allocation. I find no evidence that farmers alter their fallowing based on land use upstream. I then investigate whether market failures encourage fallowing. If farmers cannot purchase inputs used in cultivation due to liquidity constraints, they may keep more land under fallow than optimal. I use the estimated production function parameters to determine whether each farm's allocation of land between cropping and fallow is efficient from an individual perspective. I then estimate the effect liquidity indicators on land use efficiency. I find that over-fallowing is negatively associated with commercial credit use and off-farm income, suggesting that liquidity constraints do hinder agricultural intensification. Because I find evidence to support the existence of positive externalities to fallow, the loosening of liquidity constraints that encourage fallowing has ambiguous implications for community-level welfare.Item HISTORICAL AND COMPUTATIONAL ANALYSIS OF LONG-TERM ENVIRONMENTAL CHANGE: FORESTS IN THE SHENANDOAH VALLEY OF VIRGINIA(2005-08-01) Wilson, James W.; Geores, Martha E; Geography; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)The increase and decrease of forests is a major factor of land cover change. This study of forest change in the Shenandoah Valley builds upon the rich historiography of the region through the analysis of generalized and spatially explicit primary and secondary sources covering the period of 1700 to 2000. Combining geo-historical and geo-computational approaches produced a more robust picture of land cover change than would be possible using only one method. Comparing modern and historical reports on the timing of forest clearance and re-growth revealed that a discrepancy existed between the spatially explicit sources and existing historical interpretations regarding the timing and location of forest clearance and re-growth. Understanding this discrepancy is important for the interpretation of forest change and its implications in the Shenandoah Valley and beyond. Two main aspects of the study are the thorough interrogation and comparison of different data sources, and the subsequent analysis and interpretation of the data. Historic maps (1864, 1906, and c. 1945) and digital data sets derived from remotely sensed images (c. 1974 and c. 1992) were analyzed in a geographic information system (GIS) and compared to agricultural census data and published reports of land use and land cover change. Three major findings came out of this study. First, the spatially explicit sources produced values for the amount of cleared area that were within 0.5 to 2.7% of the same information derived from the agricultural census. Second, the maximum amount of forest clearance occurred 25 - 50 years later than existing published reports indicated. Third, the commonly held explanations of federal land acquisition and the abandonment of farms on steep slopes did not account for the observed patterns of forest re-growth. The documented variations in spatial and temporal patterns and reasons for the variations have impacts on our understanding of cultural and physical processes that took place in the region.Item INTEGRATED ECOLOGICAL ECONOMIC MODELING OF ECOSYSTEM SERVICES FROM THE BRAZILIAN AMAZON RAINFOREST(2004-10-26) Portela, Rosimeiry G.; Costanza, Robert; Marine-Estuarine-Environmental Sciences; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)This dissertation links the natural and social sciences, using modeling techniques to enhance understanding of the functioning of a complex ecosystem and its relevance to humans. For this purpose, I developed a Regional Unified Metatomodel of the Brazilian Amazon (RUMBA) to simulate the Amazon forest provision of ecosystem goods and services and their contribution to human economy and welfare. The model was also used to simulate the potential effect of an incentive to reduce deforestation in return for a payment for avoided releases of carbon into the atmosphere. Simulation was done from 1975 to 2100, with calibration performed for the first 25 years, and for four scenarios: a baseline scenario, based on historical trends, and four alternative scenarios based on different assumptions and policy choices. The baseline scenario shows deforestation proceeding at high rates, leading to decreasing provision of forest goods and services and increasing economic growth. The growth of GRP per capita, on the other hand, remains much smaller than that of GRP. Regional welfare decreases significantly over the simulated period. The overall monetary contribution of ecosystem goods and services to the regional economy is estimated as 5 times the GRP in year 2100. Scenarios of increased investment in development yielded higher economic growth accompanied by lower levels of welfare, while opposite trends were found for scenarios of higher investment in human, knowledge and natural capital. Finally, results also show that in order for a monetary compensation to represent a significant incentive to land owners to reduce deforestation, higher prices for avoided carbon emissions would have to be set than current prices of the emerging carbon market. Main research findings are that increasing land use change in the Brazilian Amazon incurs significant losses of ecosystem services without this being adequately offset by increasing monetary income or welfare of people. This reseach has also found that in the absence of significant incentives from global beneficiaries for any one ecosystem service, or a combination of incentives addressing several types of ecosystem services, rational land uses at the local level lead to sub-optimal provision of these services from the global perspective.