SMAP土壤水分产品在淮河流域的适用性评估  

Applicability Assessment of SMAP Soil Moisture Products in the Huaihe River Basin

作　　者：王皓 郝莹 袁松[1] 陈光舟[2] 靳莉莉[2] Wang Hao;Hao Ying;Yuan Song;Chen Guangzhou;Jin Lili(Anhui Provincial Meteorological Observatory,Hefei 230000,China;Huaihe River Basin Meteorological Center,Hefei 230000,China)

机构地区：[1]安徽省气象台,安徽合肥230000 [2]淮河流域气象中心,安徽合肥230000

出　　处：《遥感技术与应用》2021年第5期1009-1021,共13页Remote Sensing Technology and Application

基　　金：中国气象局预报员专项(CMAYBY2018-032)。

摘　　要：选取淮河流域为研究区域,利用2016年6月至2019年5月流域内的313个土壤水分观测站0~10 cm土壤体积含水量数据,使用多种指标分析SMAP卫星(Soil Moisture Active Passive)9 km分辨率土壤水分产品(L2_SM_P_E)精度的空间和时间(年、月、日尺度)特征,并讨论植被、土壤、地形等对精度影响。结果表明:①整体来看,L2_SM_P_E在淮河流域达不到0.04 m^(3)/m^(3)的预期精度,存在湿区高估、干区低估的现象,但可以较好地反映流域土壤水分的空间分布特征,也能较为准确地指示高湿区和低湿区。②L2_SM_P_E的精度存在明显的区域差异和季节差异。冬季精度明显优于其他季节,流域大部分地区的无偏均方根误差(ubRMSE)均接近预期精度,且在流域北部的部分地区、伏牛山区和大别山区达到了预期精度。在春秋季,流域北部和大别山区的精度较高。夏季L2_SM_P_E的可用性较差。③L2_SM_P_E和降水有较好的一致性,对降水的响应比土壤水分观测值敏感。在降水过程中和降水结束后,L2_SM_P_E的误差以随机误差为主;当土壤相对干燥,则以系统性负偏差为主。④L2_SM_P_E的精度与采样点的土壤类型关系并不密切,山地地区的精度要优于其他地区。The Huaihe River Basin is selected as the research area.Based on the daily average data of 313 soil moisture observation stations in the Huaihe River basin from June 2016 to May 2019,the soil moisture products(L2_SM_P_E)of SMAP(Soil Moisture Active Passive)with 9 km resolution were assessed by using a variety of indicators.In addition,the influence of vegetation,soil,topography on accuracy were discussed.The results show that:(1)Generally,L2_SM_P_E cannot reach the expected accuracy of 0.04 m^(3)/m^(3) in Huaihe River Basin,which has the characteristic of overestimating in wet area and underestimating in dry area,but it can better reflect the spatial distribution characteristics of soil moisture in the basin,and also can indicate the high wet area and low wet area.(2)There are obvious regional and seasonal differences in L2_SM_P_E accuracy.The accuracy in winter is obviously better than that in other seasons,the unbiased root mean square error(ubRMSE)in most areas of the basin is close to the expected accuracy.In some northern parts of the basin and Funiu Mountains and Dabie Mountains,it has reached the expected accuracy.In spring and autumn,the accuracy of the northern part of the basin and Dabie Mountains is higher.In summer,the availability of L2_SM_P_E is poor.(3)L2_SM_P_E have good consistency with precipitation,and its response to precipitation is more sensitive than the observed value of soil moisture.During and after precipitation,the error of L2_SM_P_E is mainly random error;when the soil is relatively dry,it is mainly negative systematic error.(4)The accuracy of L2_SM_P_E is not closely related to the soil type at the sampling point.The accuracy of mountain areas is better than other areas.

关 键 词：SMAP 土壤水分 淮河流域 评估 

分 类 号：S152.7[农业科学—土壤学] TP79[农业科学—农业基础科学]