Experimental study on ecological water use in a gully catchment of the loess plateau: effects of climate and land use change

Based on the data from the map of climate,soil water and land use(1982 and 2002)in Anjiagou catchment in the loess plateau,this paper studies the change of land use,the evapotranspiration,the ecological water use for the different plant species and the catchment,and its the correlation with the change of the climate and the land use. The results indicate that (1)the the structure of land use in Anjiagou catchment had significant change from 1982 to 2002. The cropland(especially the terraces)increases while the woodland decreases significantly because of the deforestation and the expansion of the waste-land;(2)The ecological water use for all the vegetation types is controlled by the climate,and had significant variability in the study period;(3)The evapotranspiration and the ecological water use for the woodland and the shrubland was higher than those for the cropland and the natural grassland;(4)The water consumption for cropland was close to that for the natural grassland,but the water consumption for the woodland and the shrubland was significantly higher than that for the natural grassland;And(5)the ecological water use in Anjiagou catchment decreased from 1982 to 2002 due to the decrease of the woodland,which had increased the water balance of the catchment.