Hyper-spectral estimation method of total nitrogen content of rice leaves and estimation model constructing method

Abstract

An embodiment of the invention discloses a hyper-spectral estimation model constructing method of total nitrogen content of rice leaves. The method comprises steps as follows: multiple experimental plots are selected, and multiple sampling points are selected in each experimental plot; canopy spectral measurement is performed at the critical growing stage of rice; multiple sampling spectrums are recorded at each sampling point, and an average value is taken as a spectral measurement value of the sampling point; a hyper-spectral image of each experimental plot is acquired by an airborne imaging spectrometer; multiple function leaves at different parts are collected at each sampling point, and the total nitrogen content of the rice leaves is measured; the hyper-spectral estimation model of the total nitrogen content of the rice leaves is constructed with the adoption of spectral indexes or a partial least-squares regression method. The embodiment of the invention further discloses a hyper-spectral estimation method of the total nitrogen content of the rice leaves. The total nitrogen content of the rice leaves is estimated according to the model constructed with the method. The scientific and technical basis can be provided for space inversion of the nitrogen content of regional-scale rice and efficient implementation of precision agriculture.

Description

technical field [0001] The invention relates to the field of rice monitoring, and more specifically, the invention relates to a method for hyperspectral estimation of total nitrogen content of rice leaves and an estimation model construction method. Background technique [0002] Nitrogen is the nutrient element most closely related to crop photosynthesis, yield and quality, and also the mineral element with the largest demand and application amount of crops. When crops are deficient in nitrogen, it will not only affect crop yield but also reduce its quality. On the contrary, if nitrogen nutrition is excessive, it will cause certain non-point source pollution to water and atmosphere [1] . In the practice of farmland production, nitrogen fertilizer should be used efficiently to reduce environmental pollution in order to achieve high quality and high yield of crops. Therefore, it is an urgent need for modern agricultural production to quickly and accurately obtain crop nitro...

AI Technical Summary

Problems solved by technology

At present, the estimation of rice nitrogen content in China is mainly aimed at southern paddy fields, and the established prediction model may not be applicable to rice in Northwest China; previous studies may not have been optimized for the richness and continuity of hyperspectral data. The inversion of rice nitrogen content in regional scale by man-machine hyperspectral imagery is rarely involved

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