Variation of temperature, precipitation and runoff depth enfluencing water contamination in Liao River basin, China

Temporal and spatial variation in temperature, precipitation and runoff depth in Liao River basin, China, during the period of 1969-2009 was investigated. The analysis results revealed a general pattern of increase in temperatures, and decreases in precipitations and runoff depths in Liao River basin. As a result of the reduction of runoff depth coupling with the increase of pollutants discharging, water contamination was exacerbated. Therefore, runoff depth was one of the important factors influencing the water contamination. The spatial variation of annual mean temperature was more obvious from the west to the east, especially in the central plain, and the temperature in the middle of the region was higher than that in the sides of the region. The spatial variation of annual mean precipitation was increasing from the west to the east, and the runoff depth had a similar pattern with the precipitation.