Impacts of climate and land-cover changes on water resources in a humid subtropical watershed: a case study from East Texas, USA

摘要

This study investigates the response of water resources regarding the climate and land-cover changes in a humid subtropical watershed during the period 1970-2009. A 0.7 degrees C increase in temperature and a 16.3% increase in precipitation were observed. Temperature had a lower increase trend, and precipitation showed definite increasing trend compared to previous studies. The main trend of land-cover change was conversion of vegetation and barren lands to developed and crop lands affected by human intervention, and forest and grass to bush/shrub which considered to be caused by natural climate system. Hydrologic responses to climate and land-cover changes resulted in increases of surface run-off (15.0%), soil water content (2.7%), evapotranspiration (20.1%) and a decrease in groundwater discharge (9.2%). We found that surface run-off is relatively stable with precipitation, whereas groundwater discharge and soil water content are sensitive to changes in land cover, especially land cover brought about by human intervention.