Effects of Grassland Degradation on Air and Soil Temperature in Songnen Plain of Northeast China

Grassland degradation due to human activities is a critical problem in Songnen plain of northeast China, but the possible regional climate changes, especially air and soil temperature changes because of grassland degradation, are still not clearly known. From May to September of 2014, we simulated a Leymus chinensis degradation experiment in Songnen plain to study the effects of grassland degradation on air temperature, soil temperature and the difference between soil and air temperatures. The results demonstrated that grassland degradation will increase both the growing season surface air and soil temperature by 0.49-1.49°C and 0.6-2.27°C respectively. The difference between soil and air temperatures also increases with the reduction of L. chinensis vegetation cover, implying that the increase in soil temperature will be much faster than air temperature with the degradation of the grassland in Songnen plain.