GLDAS-NOAH土壤湿度资料在中国区域的适用性分析

Applicability Analysis of GLDAS-NOAH Soil Moisture Data in China

本研究利用中国观测土壤湿度和GLDAS-NOAH土壤湿度资料,通过对比分析,研究了GLDAS-NOAH土壤湿度资料在中国区域的适用性。结果表明GLDAS-NOAH的土壤湿度模拟结果可以较好的反映中国观测土壤湿度的空间分布状况和时间变化趋势。模拟的土壤湿度呈现出由西北向东南递增的分布格局,低值区位于新疆南部和内蒙古中部,和高值区位于湖南东部,江西中部。观测土壤湿度从浅层(0~10 cm)到深层(0~50 cm)显著增大,而模拟土壤湿度随深度无明显变化。在时间变化上,模拟和观测土壤湿度都在东北平原、河套地区和新疆南部呈现出减小的趋势,在河套地区、辽宁土壤湿度都有增加的趋势。在对东北、河套和江淮三个地区进行详细模拟效果分析中,在江淮地区模拟的效果最好,河套次之。GLDAS-NOAH土壤湿度资料存在不足之处,即对深层(0~50 cm)土壤湿度的模拟效果较差。

In this study, the applicability of GLDAS-NOAH soil moisture data in China was studied by comparing the observed soil moisture with GLDAS-NOAH. The results show that GLDAS-NOAH simulation results of soil moisture can better reflect the spatial distribution and temporal trend of soil moisture observed in China. The simulated soil moisture showed an increasing distribution pattern from northwest to Southeast. The low value areas were located in the south of Xinjiang and the middle of Inner Mongolia, and the high value areas were located in the east of Hunan and the middle of Jiangxi. The observed soil moisture increased significantly from the shallow layer (0 - 10 cm) to the deep layer (0 - 50 cm), while the simulated soil moisture did not change significantly with the depth. In terms of time variation, the simulated and observed soil moisture showed a decreasing trend in the Northeast Plain, Hetao region and the south of Xinjiang, and an increasing trend in Hetao region and Liaoning Province. Among the detailed simulation results of northeast, Hetao and Jianghuai areas, Hetao is the best, followed by Hetao. GLDAS-NOAH soil moisture data has shortcomings: the simulation effect of deep (0 - 50 cm) soil moisture is poor.