Abstract: Ningxia is located in the Loess Plateau, the trend of vegetation change directly affects the ecological protection in this place. This paper uses MODIS NDVI monthly synthetic products from 2005 to 2015 to get annual NDVI data with the maximum synthetic method, and adopts the unitary linear regression method and the Sen+Mann Kendall method to analyze the vegetation change trend and spatial difference in Ningxia in recent ten years. The results show that the monthly mean value of NDVI presents Gauss distribution, and the best stage of vegetation growth is from July to September. The yearly NDVI value increases significantly in 2005—2007, the yearly NDVI value increases steadily in 2008—2012, and the yearly NDVI value decreases in 2013—2015. The trends in vegetation change obtained by the one-dimensional linear regression method and the Sen+Mann-Kendall method are almost the same, with both the overall improvement of vegetation in the north, but local urban vegetation degradation is more serious; slight improvement in the central region, local obvious improvement. The vegetation in the south is significantly improved and the area of vegetation improvement was larger. The difference between the two methods by differential analysis is only 22.95%, and the Sen+Mann-Kendall method is better for monitoring of areas of slight variation and the trends are more accurate.

Key words: Ningxia, NDVI, maximum value composite, univariate linear regression, Sen+Mann-Kendall