Showing papers by "Timothy O. Randhir published in 2014"

Resilience of Watershed Systems to Climate Change

Abstract: Climate change can have significant impact on watershed systems. These impacts are expressed in the form of impairment in water supplies, increase in natural disasters, increased exposure to waterborne contaminants, water quality issues, species extinction, biodiversity loss, economic losses, and rapid resource exploitation. The intensification of the hydrologic cycle resulting from climate change result in increased storm flows, intensity of droughts and floods, and changes to the Eco hydrologic processes of watershed systems. Impacts vary depending on the geographic location and state of the watershed system. For example, some watersheds in dry regions of sub-Saharan Africa face threats of severe droughts and desertification, while other watersheds with high moisture regime like northeast India face increased intensity in precipitation and higher flood regime. These impacts result in changes to the Social and Ecological Systems (SES) [1] of watershed and create transitory or permanent changes in watershed systems. The magnitude of impacts varies depending on the resilience [2] of the SES [3] of the watershed system. Resilience of watersheds reflects the ability of the SES to absorb climatic disturbances and to reorganize itself to maintain itself within the current domain or transform to another new stable domains in both ecological and social dimensions [4]. This is specified resilience as this reorganizational ability is specific to climate change and not to other stressors that watersheds face.

Spatial Risk Assessment of Farming on Wetland Habitats in Watershed System

Abstract: Natural resource habitats, which are isolated from the surface water bodies, are often unregulated and face a higher risk of degradation. Vernal pools, habitats for amphibians, are vulnerable to external stressors that often lead to decline in biodiversity. There is a need to protect these through conservation measures at a spatially targeted level. This study is conducted in the Middle Connecticut River Watershed of Massachusetts State. We evaluate the risk faced by isolated vernal pools at the subwatershed scale. The assessment involves the impact of agricultural intensity and vernal pool distribution in proximity to agriculture parcels. This is performed using geoprocessing techniques within a geographic information system (GIS). The spatial data are used in a nonlinear regression model to evaluate potential stressors to vernal pool existence. The model included land use, geographic features, and hydrographic factors. Agriculture and open land positively influence vernal pool existence, because of vernal pool association with low-lying areas. In addition, elevation showed a negative influence on the number of vernal pool habitats. The results of the spatial risk evaluation of habitat are helpful to target efforts on specific subwatersheds in conserving vernal pool habitats.