Feasibility of Field Evaluation of Rice Nitrogen Status From Reflectance Spectra of Canopy *1  

Feasibility of Field Evaluation of Rice Nitrogen Status From Reflectance Spectra of Canopy

作　　者：WANG RENCHAO, WANG KE and SHEN ZHANGQUAN Institute of Agricultural Remote Sensing and Information Application, Zhejiang Agricultural University, Hangzhou 310029 (China) 

出　　处：《Pedosphere》1998年第2期121-126,共6页土壤圈（英文版）

摘　　要：Techniques for measurement of the N status of rice can be an aid to making management decisions with economic and environmental implications. A field experiment was conducted to identify spectral variables most sensitive to N deficiency detection in rice canopy with the possibility for their use as a management tool. Spectral and agronomic measurements were collected in the evaluation experiment of N status from rice canopy under five N treatments in a silt loam soil. Nitrogen fertilization effects were seen across the entire wavelength measured. Red reflectance decreased and near infrared reflectance increased with increasing N fertilizer application. Spectral differences between treatments were seen throughout the test period. The near infrared reflectance/red reflectance ratio (RVI) differed more between treatments than between single bands. Variations in canopy reflectances due to other environmental factors were reduced by the use of RVI. In the spectral variables examined, the RVI separated the treatments most effectively, and three or four treatments can be separated. Differences in spectral responses between the treatments were attributable to leaf area index, leaf chlorophyll concentration and phytomass, which all changed with N fertilization.ＩＮＴＲＯＤＣＴＩＯＮＲｉｃｅｉｓｏｎｅｏｆｔｈｅｍａｉｎｃｒｏｐｓｉｎＣｈｉｎａ．Ｎｉｔｒｏｇｅｎｆｅｒｔｉｌｉｚｅｒｍａｎａｇｅｍｅｎｔ，ｅｓｐｅｃｉａｌｙｔｏｐｄｒｅｓｓｉｎｇｗｈｉｃｈｒｅｓｕｌｔｓｉｎｈｉｇｈｅｒｙｉｅｌｄｗｉｔｈｏｕｔｌ...

关 键 词：canopy spectra nitrogen fertilizer nitrogen status evaluation RICE 

分 类 号：S511[农业科学—作物学] S143.1