宁夏不同植被类型NDVI变化特征及其对气候的响应.

It is important to quantitatively analyze the driving mechanisms of vegetation cover changes and explore the relationship between vegetation and climate factors for regional ecological environment evaluation and soil and water conservation. Based on the normalized difference vegetation index(NDVI)in Ningxia from 1998 to 2019, the trend analysis, partial correlation analysis and variance decomposition of RDA were used to investigate the spatial-temporal variation characteristics of NDVI of different vegetation types and their driving factors. The results show that ① the annual growth rate of NDVI is 0.007 1 a-1, with the lowest NDVI growth rate in spring(0.002 3 a-1)and the highest NDVI growth rate in autumn(0.007 5 a-1); the NDVI growth rates of coniferous forests, shrub and desert are the highest in summer, and the NDVI growth rates of broad-leaved forests, farmland, grasslands and meadows are the highest in autumn; ② on the annual scale, 93.4% of the regional NDVI show an improving trend; within different seasons, the vegetation degradation is serious in spring, 16.6% of the vegetation area show a decreasing trend, which mainly occur in the yellow irrigation area of northern Ningxia, and the degraded areas in other seasons are concentrated around Yinchuan city; ③ climate is the main factor affecting the vegetation change, NDVI is positively correlated with temperature throughout the year and in spring, while NDVI and temperature are negatively correlated in summer, and NDVI and precipitation are positively correlated in different seasons. [ABSTRACT FROM AUTHOR]