| Vegetation is very important for protecting ecology and improving human living environment.It is one of the current important methods to evaluate ecological changes by establishing a long-term sequence vegetation coverage remote sensing data set of a certain area to monitor the vegetation coverage changes in the selected area.The growth and development of vegetation in the natural world is mainly influenced by two main factors,natural and human factors in the area.Natural factors affect the natural differences and evolution of vegetation ecology in a region in a short period of time.However,due to subjectivity and uncertainty,human activities have a dramatic impact on the vegetation ecological changes within a short period of time.In recent years,the local vegetation ecological succession and change process has been restricted by both natural and human factors in the region.Therefore,to study the vegetation cover succession and change and analyze the influencing factors of vegetation cover changes in this area,clarify that natural and human factors are affecting The proportion in the ecological process can provide scientific basis for vegetation ecological maintenance and management in this area,and has important theoretical significance.In terms of research methods,the vegetation coverage reflectance data on the surface of Hulunbuir grassland animal husbandry four banners were used as data sources to construct the research area normalized gimmsndvi3 G from 1982 to 2015 In the V1 vegetation index data set,trend analysis method,reverse distance difference method,residual analysis method and quantitative detection of vegetation cover trend change and its influencing factors in different time scales in Hulunbuir grassland animal husbandry four banners were used.In terms of research content,the spatial and temporal evolution trend of NDVI and analysis of its influencing components in Hulunbeier Grasslandduring April September of 34 years were discussed.The height of the grass layer,the coverage,the aboveground biomass and the proportion of the best grass were collected through the field observation for 12 years.The availability of 34 year vegetation coverage remote sensing data in Hulunbuir grassland was verified by field investigation.It can be seen from the research that:1.The vegetation coverage in xinbaluyou banner tends to be better,and the improvement is most significant after 2004.The change trend of xinbalhuzuo banner,chenbalhuqi banner and Ewenki Autonomous Banner is the same.The change trend of inter vegetation coverage from 1982 to 1999 is relatively stable,without significant fluctuation.The inter vegetation coverage from 2000 to 2007 decreased,and then showed a stable upward trend.It can be seen that the change trend of vegetation cover in the four banners of animal husbandry is synchronous with that in each banner.On the time scale,NDVI increased slowly in the growth period of the study area from 1982 to 2015;on the space scale,NDVI showed the overall low,especially the low vegetation coverage trend in xinbaluyou banner and xinbaluzuo banner.2.The relationship between vegetation cover change and climate factors in the study area showed a positive correlation with precipitation,a more negative correlation with temperature,a closer relationship with accumulated precipitation in the growing season,and a positive correlation with humidity.3.Quantitative analysis of the relative role of climate factors and human factors in the process of regional vegetation ecological evolution by using the actual NDVI and potential NDVI in the study area shows that the impact of the two factors on the ecological environment of the study area is two-way,and the contribution percentage of climate change to the growth of NDVI in the study area is gradually increasing,while the human factors are gradually decreasing The influence of natural factors on Vegetation Ecology in the study area is gradually increasing. |
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