水稻冠层光谱反射特性的动态变化研究

A STUDY ON DYNAMIC CHANGES OF RICE REFLECTIVE CHARACTERISTICS IN GROWTH PERIOD

通过对早稻整个生长期内冠层反射光谱特性动态变化的系统研究表明：①在整个水稻生长期内，水稻冠层反射光谱的比值植被指数（ＲＶＩ）值呈有规律的变化，在抽穗前，随移栽后天数增加，ＲＶＩ值也逐渐增大，至抽穗前达到最大值；而抽穗后，则随着移栽后天数的增加，ＲＶＩ值逐渐下降，至收割前降至最低值；②积温与ＲＶＩ之间存在着较密切的关系，通过对不同生育期积温与ＲＶＩ之间进行的线性回归分析表明，在抽穗前，积温与ＲＶＩ值之间呈极显著正相关；而抽穗后，积温与ＲＶＩ之间呈极显著的负相关。在遥感估产中。

With the systematic research of canopy reflective alternation during early rice growth period, the results could be summarised as follows: 1.The RVI value varied regularly during growth period. Before heading, with days increasing after trasplanting, RVI value increased straightly, and it reached the maximum value just before heading; howerver, after heading, RVI value decreased with the days increasing after trasplanting. 2.There existed closely relation between accumulated temperature and RVI value. According to linear regression analysis about accumulated temperture and RVI value, it was found that: Before heading, they had marked positive relation, and in the other hand, they had notable negative relation after heading. These results maybe useful to correct the error of growth stage and improve the accuracy of yield estimation in yield estimation by remote sensing.