新疆焉耆盆地土壤湿度时空分布特征

本文以新疆焉耆盆地为研究区，首先利用实测数据和Landsat 8 OLI遥感数据获取土壤调查植被指数（MSAVI）和地表温度（Ts），构建Ts-MSAVI特征空间，拟合特征空间的干湿方程；然后利用该特征空间计算温度植被干旱指数（TVDIm），反演9-11月的土壤湿度，探讨土壤湿度时空分布特征。试验结果表明：①遥感影像反演的TVDI与实地考察的土壤湿度显著相关（a=0.05）；不同土层中，TVDIm与10~20 cm土层湿度相关性最高（R=0.588）；②焉耆盆地湿度总体以半干旱为主（0.60.8）；土壤湿度空间分布上，焉耆盆地南侧为干旱区，西部和北部地区偏干旱，中部为湿润区域，对于该地区滨湖湿地和博斯腾湖附近小湖土壤湿度最高，博斯腾湖南部的沙地区土壤湿度最低，Ts与土壤湿度呈负相关；③10月湿地的TVDIm值最低，9月沙地的TVDIm值最高。TVDI模型应用于焉耆盆地取得较好的结果，可用于正确地估算土壤湿度，研究结果可为焉耆盆地生态环境和水资源提供重要的参数。

Yanqi basin soil moisture spatial and temporal distribution characteristics in Xinjiang

This study takes Xinjiang Yanqi basin as the research area,using field data and Landsat 8 OLI data to obtain soil vegetation index MSAVI and land surface temperature (Ts) to construct Ts-MSAVI feature space combined with dry and wet space equations. The temperature vegetation drought index (TVDIm) is calculated using this feature space, retrieve soil moisture in September, October, and November, analyzes the temporal and spatial distribution characteristics of soil moisture. The result shows that:① The TVDI retrieved from remote sensing images is significantly correlated with soil moisture (a=0.05). TVDIm has the highest correlation with 10~20 cm soil moisture (R=0.588) in different soil layer. ② Humidity level in Yanqi basin is featured with semi-arid(0.60.8). Spatial distribution of soil moisture denotes that the arid area is mainly distributed the southern side of the Yanqi basin, the western and northern part of the Yanqi basin is arid, and the humid area is the middle of the Yanqi basin. For this area, the lake side wetland and the small lake of Bosten Lake have the highest soil moisture, and the sandy area of the southern Bosten Lake has the lowest soil moisture.③ The wetland showes the lowest TVDIm value in October. The TVDIm value of the sandy land is the highest in September. The TVDI model has been applied in Yanqi basin to obtain good results, which can be used to accurately estimate soil moisture. The research results can provide important parameters for the ecological environment and water resources of Yanqi basin.