农业干旱遥感监测的原理、方法与应用

Principle，method and application of remote sensingmonitoring of agricultural drought

关键词:  农业  干旱  遥感监测  原理  方法  应用

Key words:  agriculture  drought  remote sensing monitoring  principle  method  application

摘要:

目的 干旱遥感监测是卫星遥感技术的重要应用和研究方向之一，是对气象、地面调查等技术手段开展农作物干旱监测的重要补充和参考。方法 在总结国内外目前主要的干旱遥感监测方法基础上，将农业干旱遥感监测方法概括为7个大类，即基于热惯量、冠层温度、作物长势状况、综合冠层温度与作物长势、蒸发（腾）、微波、作物生长模型的干旱遥感监测方法，并对各类方法的主要形式进行了系统性总结。结果 同前主要的干旱遥感监测方法中，除作物生长模型的反演的监测是土壤含水量外，其他方法大多数是基于遥感度量的干旱程度指标，需要结合地面水分观测值等的标定转化为土壤的水分含量。结论 从监测原理上看，农业干旱可以认为是光照条件、土壤质地、作物长势、冠层温度4个物理量的函数。在自然条件下，当某个或几个物理量相对一致时，就可以将该理论模型进行简化，使用特定的干旱指数形式对干旱进行量度，这也是当前遥感监测技术监测作物干旱的主要思路。同时，该文对当前国内和国际上的主要干旱遥感监测业务化运行系统进行了介绍，并在此基础上，结合当前遥感监测方法区域适用能力存在的局限性，提出模型区域适应性改进是当前旱情遥感监测业务应用的关键点。同时，随着中高分辨率遥感数据的日益增多，利用中高分辨率卫星数据进行定量化干旱遥感监测技术也是当前干旱遥感监测的重要趋势。此外，干旱遥感监测的不确定性研究也是业务化应用中需要加强的一个方向。

Abstract:

Purpose Drought remote sensing monitoring is one of the important applications and study directions of satellite remote sensing technology，and is an important supplement and reference of crop drought monitoring of technological means such as weather and ground survey，etc.Method The paper，based on the existing drought remote sensing monitoring methods both in China and abroad，classifies the agricultural drought remote sensing monitoring methods into 7 major groups，namely，the drought remote sensing monitoring methods based on thermal inertia，canopy surface temperature，crop growth condition，combination of canopy surface temperature and crop growth condition，evaporation （transpiration），microwave，and crop growth model，respectively.The paper also provides a systematic summarization on the major forms of these methods.Result Among these methods，except for the inverse of crop growth model，which monitors soil water content，most methods are based on the drought indexes measured by using remote sensing technology，which needs to be converted into soil water content by combining the observation values of ground water contents，etc.Conclusion From the perspective of monitoring principles，agricultural drought can be taken as a function of 4 physical quantities of light condition，soil texture，crop growth，and canopy surface temperature.Under natural conditions，when one or several physical quantities are relatively consistent，the theoretical model can be simplified，and the drought can be measured by using specific drought index form，which is also the main idea of current remote sensing monitoring technologies to monitor crop drought.Meanwhile，the paper systematically introduces the major business operations of drought remote sensing monitoring both in China and abroad，and based on this，the paper proposes the key point of current drought condition remote sensing monitoring，which is the improvement of adaptability of the model area by considering the limitation of current remote sensing monitoring method on the adaptability of the specific area.Meanwhile，along with the gradual increase of remote sensing data with medium and high resolution，using medium and high resolution satellite data to conduct drought remote sensing monitoring with quantitative drought remote sensing monitoring technology is an important trend of drought remote sensing monitoring.In addition，researches on uncertainties of drought remote sensing monitoring need to be reinforced in the business operations.