作物学报2018,Vol.44Issue(7):1043-1054,12.DOI:10.3724/SP.J.1006.2018.01043
GF-1和MODIS影像冬小麦长势监测指标NDVI的对比
Comparison of Growth Monitoring Index NDVI between GF-1 and MODIS Images in Winter Wheat
摘要
Abstract
Crop growth status is one of the major contents of agriculture remote sensing monitoring. For a long time, crop growth status remote sensing monitoring has been mainly based on related vegetation parameters inverted from satellite images, such as normalized difference vegetation index (NDVI), leaf area index (LAI). In this study, we made an attempt to set up a quantitative relation between remote sensing monitored crop growth indices and ground observation indices of actual crop growth, by com-parative study of NDVI based on the GF-1 satellite image with resolution of 16 m and the MODIS image with the resolution of 250 m and comprehensive stalk number (CSN), plant height (PH), and leaf chlorophyll concentration (LCC) of winter wheat. GF-1 NDVI had the highest correlation with CSN (R2= 0.8961), while other indices had relatively low correlation. In contrast, MODIS NDVI had relatively lower correlation with CSN of winter wheat (R2= 0.4432), and the accuracy in crop growth remote sensing monitoring was relatively low. The average NDVI value of GF-1 pixels within MODIS winter wheat pixels was measured and found to be weakly correlated with MODIS NDVI (R2= 0.3944). However, the wheat growth monitoring accuracy by MODIS images was improved (R2= 0.4633) after eliminating the sensor spectral response function difference and scale effects. By ranking the standard deviations of GF-1 NDVI within the MODIS pixels, we found that higher winter wheat growth consistency within MODIS pixels resulted in higher monitoring accuracy of MODIS remote sensing. The NDVI from GF-1 or MODIS image mainly represented CSN, and the NDVI value from higher solution image had a better reflection of actual winter wheat growth. When the winter wheat growth consistency within MODIS pixels was high, the difference of NDVI between MODIS and GF-1 data was small. From the perspective of long term regional growth monitoring, although spectrum and scale normalization can further im-prove the consistency of monitoring result, the overall accuracy of MODIS NDVI growth monitoring is relatively low. In order to meet the demand of precise monitoring on crop growth, it is necessary to use high-resolution remote sensing data to replace mid-dle- or low-resolution data for crop growth remote sensing monitoring, and take it as the research focus of the business operation of crop growth monitoring.关键词
归一化植被指数/MODIS影像/GF-1影像/遥感监测/冬小麦Key words
NDVI/MODIS image/GF-1 image/remote sensing/winter wheat引用本文复制引用
王利民,杨玲波,刘佳,杨福刚,姚保民..GF-1和MODIS影像冬小麦长势监测指标NDVI的对比[J].作物学报,2018,44(7):1043-1054,12.基金项目
本研究由国家重点研发计划项目(2016YFD0300603)资助.This study was supported by the National Key R&D Program of China (2016YFD0300603). (2016YFD0300603)