基于MODISEVI的左江流域耕地利用效率评价

选取左江流域多年中分辨率成像光谱仪（MODIS）增强植被指数（EVI）时间序列数据进行研究，利用最佳坡度系数截取法（BISE）和Savitzky-Golay滤波法对数据进行平滑去云处理，设计二次差分算法，提取耕地EVI在1 a内时间序列峰值频数。将峰值频数图像与土地利用现状图叠加分析，得到左江流域耕地的利用效率。抽取样本进行线性回归分析，R值达到0.734 9，表明取得了理想的结果，丰富了耕地利用效率研究的方法。

Evaluation on Cultivated Land Use Efficiency in Zuojiang River Basin Based on MODIS EVI

The MODIS/EVI time series data in Zuojiang River basin were selected to be analyzed. It removed cloud contaminated images by BISE and Savitzky-Golay algorithm. By using two times differencing, this paper extracted the number of peaks of time series of EVI profile. Moreover, it made overlay analysis with images of peaks and the actual land use map to obtain cultivated land use efficiency in Zuojiang River basin. The R value of selected samples was up to 0.734 9 by linear regression analysis, which illustrated the good result, and enriched the methods of analysis on cultivated land use efficiency.