基于光谱指数的伊犁绢蒿荒漠草地恢复状况的判定

Estimation of the Restoration Status of Seriphidium transiliense Desert Grassland Based on Spectral Index

为了从光谱角度探讨退化伊犁绢蒿封育的适宜年限,对未封育、封育2年、7年和10年的草地从群落数量指标、群落光谱特征及特征植物光谱进行研究。通过对植被数据与光谱数据进行回归分析,对比群落和特征植物光谱指数随封育年限的变化趋势,探讨植被高光谱对伊犁绢蒿荒漠草地恢复状况的响应及最佳封育年限判定的可行性。结果表明:随着封育年限的增加,草地的盖度、密度及生物量呈先增加后降低的趋势;对群落的数量指标、群落光谱指数及建群种光谱指数回归均指示在5年左右达到最大值,表明可以通过植物光谱来对草地恢复状况及封育最佳年限加以判定。

In order to explore the suitable fencing years for degraded Seriphidium transiliense desert grassland from the perspective of spectrum index,the quantitative indices of the community,the spectral characteristics of the community,and the spectrum of the typical plants of grassland were studied for the unenclosed,fenced for 2,7 and 10 years.Through the regression analysis of vegetation data and spectral data,and the trend analysis of the spectral indices of the community and characteristic plants with the extension of the enclosure years,the response of the vegetation hyperspectral to the restoration and the feasibility of the determination of the best enclosure period were explored.The results showed that with the increase of the fencing time,the coverage,density and biomass of the grassland increased firstly and then decreased.The community quantity indices,community spectral indices and the spectral index of the typical plants were all indicated that the maximum value was in about 5 years,which indicated that it was possible to judge the restoration status of the grassland and the optimal period of enclosure by using the plant spectrum index.