中国生态农业学报2017，Vol.25Issue(12)：1832-1841,10.DOI:10.13930/j.cnki.cjea.170996
无人机搭载数码相机航拍进行小麦、玉米氮素营养诊断研究
Diagnosis of nitrogen nutrition of winter wheat and summer corn using images from digital camera equipped on unmanned aerial vehicle
摘要
Abstract
The large number of population and scarce land resources require crop yield per unit area to be increased greatly to ensure the food supplies and food security in China. To meet this requirement, chemical fertilizer application is an important and simple measure. Consequently, the agricultural non-point pollution caused by chemical fertilizer is becoming more and more serious. Precision fertilization is one of the important technologies to control agricultural non-point source pollution, while soil nutrient testing and crop nutrition diagnosis are indispensable works of precision fertilization. With the increasing of agriculture scale management, it is urgent to develop fast, economic and nondestructive techniques of the nitrogen nutrition diagnosis of crops. In this study, in the light of related researches of diagnosis of nitrogen nutrition in winter wheat and sum-mer corn using digital photographs, cost-effective unmanned aerial vehicle (UAV) system was introduced and digital camera mounted on its platform was used to obtain the canopy photographs of crops. To determine the appropriate aerial heights and sensitive color parameters of aerial photographs for the diagnosis of nitrogen nutrition of winter wheat and summer corn, the relationships between a variety of color parameters retrieved from the aerial photographs obtained at different heights and the status of nitrogen nutrition of winter wheat and summer corn measured in situ in 2015 were analyzed. It was indicated that VARI (visible atmospherically resistant index based on digital photography) and B/(R+G+B) were the most sensitive color parameters for the diagnosis of nitrogen nutrition in winter wheat and summer corn, respectively. For the winter wheat, 16 m was the suitable aerial height at jointing stage, and the diagnosis model was: stem sap nitrate concentration =2.103 4e18.874VARI. 50 m was the best aerial height for summer corn at big trumpet stage, and the diagnosis model was: vein nitrate concentration = 1.526×1032×[B/(R+G+B)]50.445. The established diagnose models were verified at the same field in 2016. The results showed that the determination coefficients of relationship between predicted and observed nitrate nitrogen concen-trations of stem sap of winter wheat and vein of summer corn were 0.80 and 0.85, respectively, with significant levels of P <0.01. In 2017, the method was applied to the diagnosis of nitrogen nutrition of winter wheat and summer corn in Nanpi County, Hebei Province, and the prescription maps of top-dressing nitrogen fertilizer for winter wheat and summer corn were made. The nitrogen fertilization rates of winter wheat and summer corn given by the prescription maps were fitting well with the growth status of crops. As shown in this study, diagnosis of nitrogen nutrition of winter wheat and summer corn using photo-graphs from digital camera equipped on UAV was a cost-effective way to achieve precision management of fertilization. Be-yond the achievements of this study, there were still problems should be solved to enhance the practicability and applicability of this method.关键词
精准施肥/无人机/数码相机/色彩参数/航拍高度/硝酸盐浓度/氮素营养诊断/冬小麦/夏玉米Key words
Precision fertilization/Unmanned aerial vehicle (UAV)/Digital camera/Color parameters/Aerial height/Nitrate nitrogen concentration/Diagnosis of nitrogen nutrition/Winter wheat/Summer corn分类
农业科学引用本文复制引用
李红军,李佳珍,雷玉平,张玉铭..无人机搭载数码相机航拍进行小麦、玉米氮素营养诊断研究[J].中国生态农业学报,2017,25(12):1832-1841,10.基金项目
国家重点研发计划(2016YFD0200307)、河北省科技计划项目(14227423D)和渤海粮仓现代农业区域科技示范(KFJ-STS-ZDTP-001)资助 This study was supported by the National Key Research and Development Plan of China (2016YFD0200307), the Science and Technology Plan Project of Hebei Province (14227423D) and the Science and Technology Demonstration of Modern Agriculture in Bohai Granary Region (KFJ-STS-ZDTP-001). （2016YFD0200307）
