扎鲁特旗山地草地土壤含水量动态与气候因子的关系

Dynamic change of soil moisture and their relationship with climatic factors in the Jarud Banner of Inner Mongolia

通过对内蒙古通辽市扎鲁特旗巴雅尔吐胡硕牧业气象站1983-2012年气象数据和山地草地土壤含水量数据分析,揭示土壤含水量的动态变化及其与气候因子之间的相关关系。结果表明,1983-2012年山地草地土壤各层（0-10、10-20、20-30、30-40、40-50和0-50cm）含水量均呈现逐渐降低的变化趋势,草地逐渐旱化;土壤含水量下降过程可以分为3个阶段,第1阶段为1983-1987年,该阶段土壤含水量在15%～30%之间波动,属于土壤含水量的较高阶段;第2阶段为1988-1999年,该阶段土壤含水量在5%～15%范围内波动,属于土壤含水量高（15%～30%）向低（2%～10%）过渡阶段;第3阶段是2000-2012年,该阶段土壤含水量在2%～10%范围内波动,属于土壤含水量较低阶段;土壤含水量与温度和日照时数呈负相关,与降水量、相对湿度、蒸散量呈正相关。

In order to reveal the dynamic change of grassland soil moisture and the effects of climate chan- ges, the inter annual variations of soil moisture and the relationships between soil moisture and climatic factors were analyzed using historical climate date and soil moisture from 1983 to 2012 in the Jarud Banner of Inner Mongolia. The results showed the soil moisture in all the soil layers including 0-10, 10-20, 20-30, 30-40, 40-50 and 0-50 cm gradually decreased from 1983 to 2012 which suggested that grass- land become more and more drought. The decrease of soil moisture included 3 stages. The first stage was from 1983 to 1987 when the soil moisture ranged from 15% to 30% which was the higher moisture stage. The second stage was from 1988 to 1999 when the soil moisture ranged from 5% to 15% which was transi- tion stage from higher moisture to lower moisture stage. The third stage was from 2000 to 2012 when the soil moisture ranged from 2% to 10% which was the lower moisture stage. There was negative relationship between temperature, sunshine hours and soil moisture and positive relationship between precipitation, relative humidity, evapotranspiration and soil moisture.