基于垂直干旱指数(PDI)的灌区实际灌溉面积遥感监测方法

Remote sensing monitoring methods of actual effective irrigation area based on Perpendicular Drought Index(PDI)

灌溉面积及其分布的准确信息对于灌区的现代化管理非常重要,传统获取灌溉面积的方式并不能满足现在的需要,而卫星遥感技术则为获取灌溉面积和分布提供了新的方法与途径。构建了基于干旱指数差异阈值的灌溉面积遥感监测模型,并以宁夏地区秦汉灌区作为研究区域,进行模型的应用研究。根据实际需要,选取了环境减灾卫星(HJ1A/1BCCD)数据,计算和分析了研究区域内的垂直干旱指数(PDI)的分布和变化,通过实地考察当地情况确定了差异阈值为0.082,计算出灌区春灌第一次灌水时期各阶段的灌溉面积。经与地面监测和统计数据校验,计算结果准确率可以达到75%以上,说明了遥感干旱指数用于灌溉监测的可行性。

Irrigation area and the accurate information of its distribution are very important for the modern management of irrigation area,while the traditional way to get irrigated area cannot meet the present needs.Satellite remote sensing has provided a relatively inexpensive,accurate,rapid,large-scale,and effective way by which nationwide survey irrigated area can be repeated and distributed.In recent years,more and more satellite remote sensing data sources have provided,and data quality has improved.Using remote sensing technology in the modern management of the irrigation area is the trend of the future.This paper investigated the feasibility of monitoring the drought index of remote sensing for irrigation,and built a remote sensing monitoring model for irrigation area based on drought index difference threshold.Taking the Qinhan Irrigated Area in Ningxia Province as a research area,the application research of the model was carried out.The environmental mitigation satellite(HJ1A /1BCCD)data were selected to calculate and analyze the distribution and change of the Perpendicular Drought Index(PDI)of the study area of.The difference threshold was 0.082 by on-the-spot investigation of local conditions.Then the first spring irrigation and its changes over time scales of irrigated area were calculated.Compared and verified with the ground monitoring and statistical data,the accuracy of result could reach above 75%.The paper provided a new approach for irrigation area monitoring.