Full-Text Search:
Home|Journal Papers|About CNKI|User Service|FAQ|Contact Us|中文
《Journal of Northwest A & F University(Natural Science Edition)》 2016-05
Add to Favorite Get Latest Update

Estimating chlorophyll density of soybean under monoculture and relay intercropping by hyperspectral remote sensing

HUANG Shan;YANG Feng;ZHANG Yong;WANG Rui;DENG Jun-cai;YONG Tai-wen;LIU Wei-guo;YANG Wen-yu;College of Agronomy,Sichuan Agricultural University,Key Laboratory of Crop Ecophysiology and Farming System in Southwest,Ministry of Agriculture;  
【Objective】Hyperspectral data were used to build a chlorophyll density model,which can may provide basis for soybean growth monitoring under monoculture and intercropping systems.【Method】In this research,chlorophyll density and canopy spectral characteristics of soybean at different growth stages were analyzed under monoculture and intercropping system using Nandou 12 as species.The correlation between original spectrum,derivative spectrum,vegetation index,combination of more bands and chlorophyll density was also analyzed.The model for estimating chlorophyll density was built by comparing the relationship between hyperspectral feature parameters and chlorophyll density.【Result】The chlorophyll density in the whole growth period displayed an trend that increased first and then decreased under mono-culture and intercropping system.The maximum value of chlorophyll density appeared in the pod stage,and the monoculture system was 5.5% higher than relay intercropping system.Similar results were found in the canopy spectral reflectance of soybean in the near infrared region(700-1 000nm)with the highest reflectance spectral value of up to 70%in the pod stage.In addition,the position of red edge appeared a red shift with the increasing growth stage before the pod stage.The ratio vegetation index(507/697)had the highest correlation with chlorophyll density(r0.962,P0.01)compared with others.Compared to other models,the quadratic function model could estimate the canopy chlorophyll density better with the determination coefficient of0.75 and RMSEof 0.25.【Conclusion】The quadratic function model built with vegetation index RVI(507/697)could be used to estimate soybean chlorophyll density under monoculture and intercropping system.
【Fund】: 国家自然科学基金项目(31571615);; 农业部公益性行业科研专项(201203096)
【CateGory Index】: S565.1;S344.3
Download(CAJ format) Download(PDF format)
CAJViewer7.0 supports all the CNKI file formats; AdobeReader only supports the PDF format.
©2006 Tsinghua Tongfang Knowledge Network Technology Co., Ltd.(Beijing)(TTKN) All rights reserved