A Remote Sensing Monitoring Method for Agricultural Drought

Abstract

The invention discloses an agricultural drought remote sensing monitoring method, which comprises the following steps: 1) calculating enhanced vegetation index and land surface temperature according to surface reflectance and thermal infrared remote sensing images; 2) constructing an ETVDI model through the surface temperature and the enhanced vegetation index calculation result, and obtaining maximum value and minimum value of the surface temperature under the same enhanced vegetation index value and the number of pixel points at the points of same surface temperature values corresponding to different enhanced vegetation index values; and 3) carrying out polynomial fitting on the maximum value and minimum value corresponding to the same enhanced vegetation index value to obtain wet and dry boundary equations in the ETVDI model, and obtaining fitting parameters. The method overcomes the defect that a conventional TVDI model has vegetation index saturation easily in a dense vegetation area and the defect of uncertainty of wet and dry boundary equation fitting, thereby improving fitting precision; precision is higher in the expression aspect of temporal and spatial development of the drought; and the method can reflect the process of drought growing, development and elimination more truly, and provides reference for early warning and monitoring of the agricultural drought.

Description

technical field [0001] The invention relates to the field of remote sensing technology and vegetation monitoring research, in particular to a remote sensing monitoring method for agricultural drought. Background technique [0002] Drought has the characteristics of being difficult to detect at the initial stage, having a long cycle and spreading widely, which seriously affects regional security and social stability. Therefore, it is very important to do a good job in early warning and prediction of drought and to study drought monitoring methods suitable for the region. [0003] At present, in the study of soil moisture monitoring, the inversion research of regional soil moisture based on remote sensing technology has become an important research direction due to its advantages of wide range, high efficiency and time continuity, and many soil moisture inversion models have been established. Among them, the most widely used monitoring model is the TVDI (Temperature Vegetatio...

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Problems solved by technology

[0010] The main purpose of the present invention is to overcome the shortcomings and deficiencies of the prior art, and provide a remote sensing monitoring method for agricultural drought, which makes up for the inaccurate defect of the traditional TVDI model in the drought monitoring results in areas with high vegetation coverage, and improves the dryness and humidity. The fitting accuracy of the edge equation is good for drought monitoring in areas with high vegetation coverage, and has the advantages of fewer parameters, easy data acquisition, and accurate results

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