利用地面遥感仪器对土壤水分的监测试验

在陇东黄土高原对西峰农业气象试验站内的裸地、生长茂盛的小麦、玉米地、草地4类地物进行了CE312热红外辐射计及CE313可见光、近红外辐射计的同步观测和土壤水分的实测,试验观测数据的初步分析结果表明:热红外辐射计各通道的亮温变化与土壤水分的变化呈非线性相关,由于影响各地物亮温的因素较为复杂,主要表现为对裸地的监测效果较好,在有植被覆盖的情况下关系不明显。此外通过比较各地物亮温与植被指数发现二者有较好相关性。实践证明,利用地面遥感监测土壤水分从理论上是可行的,可进一步通过亮温和植被指数来建立试验区的土壤水分监测模型。

A Test on the Monitoring of Soil Moisture with CE312 Infrared and CE313 Visible and Near Infrared Radiometers

A test on the soil moisture monitoring with the CE312 thermal infrared radiometer and CE313 visible and near infrared radiometers was conducted at Xifeng Agrometeorological Experimental Site on the loess plateau in the east part of Gansu province.Four kinds of samples,the bare area,the wheat field,the maize field and the grassland,were selected to monitor the soil moisture synchronously with above remote sensing instruments,and carry out observation at the same time.The result indicates that the change of the brightness temperature of each channel of the CE312 is connected with the change of the soil moisture,especially they are more sensitive to the moisture of bare area and not sensitive to that of vegetation covering area,the correlation is nonlinear and its impact factor is complex.The comparison between the brightness temperature and vegetable index showed that there is a good correlation.The test proved that the ground remote sensing is available for monitoring soil moisture and the model could be set up according to the relation between the brightness temperature and vegetable index in further practice.