Spatial and Temporal Variation of NDVI in Qiandongnan Prefecture,Guizhou Province in Recent 20 Years
To explore the change characteristics of vegetation cover in Qiandongnan prefecture,Guizhou province,in order to provide scientific reference for ecological environmental protection and high-quality forestry development in Qiandongnan prefecture.Based on MODSI data of medium resolution remote sensing products,Theil-Sen Median trend analysis,Mann-Kendall test,coefficient of variation and other methods were adopted.The temporal and spatial changes of vegetation cover in southeast Guizhou province in recent 20 years were studied.The results showed as follows:The annual mean variation of NDVI in southeast Guizhou was stable(R2=0.4285),and showed an overall increasing trend,with an average growth rate of 0.0026/a.The annual variation of NDVI showed obvious seasonality,high in summer and low in winter;The mean NDVI of Qiandongnan prefecture in recent 20 years was 0.69,the overall vegetation coverage was higher,and the spatial distribution was higher in southeast and lower in northwest.The distribution was highest in Jianhe county and lowest in Kaili city.The spatial variation of NDVI in Qiandongnan prefecture was relatively stable during the study period,and the average CV was 0.06.Conclusion:The results of returning farmland to forest and grassland in Qiandongnan prefecture in recent 20 years are remarkable.It is suggested that the government should make reasonable planning of project construction land while continuing to consolidate the work of returning farmland to forest and grassland,and avoid occupying no or less forestry land.
NETL
NSTL
万方数据
