Impact of Land use Change on Precipitation and Temperature Trends in an Arid Environments

چکیده مقاله

Precipitation and temperature are the major variables in climatological and hydrological systems, especially in arid regions. The main aim of this study was to investigate the trend of precipitation and temperature of an arid area in the monthly and annual time scales. The possible relation of these climate change with anthropogenic behavior was also investigated. Observational data for temperature (12 stations) and precipitation (22 stations) have been obtained from Iran Water Resource Management Company during 1986-2012. The non-parametric method and remote sensing (RS) technology was used to analyze the possibility effects of land use and climate change on precipitation and temperature trends. The trends in precipitation and temperature were detected using Man-Kendall and Spearman's Rho tests. The LULC maps for the study area were produced using remote sensing and satellite images for the years of 1987 and 2013. The results of this study indicate that monthly precipitation had an increasing and decreasing significant trend, however monthly temperature was increased significantly in the study period. Annual Tmax exhibited a significant increasing trend for six stations in the study area. The main increasing in LULC were irrigation farming and residential area. According to the land use maps, some parts of rangeland area changed to bear soil area. We conclude that increase in urban area can be linked to higher temperature, also increasing and decreasing in irrigation farming and rangeland may influence groundwater and surface water, respectively. So, the impacts of both land use and climate change must be included in hydrological modeling and watershed management.