Spatial And Temporal Variations Of Vegetation Coverage In Urad Rear Banner And Analysis Of Influencing Factors

This paper analyzes the spatial and temporal characteristics of the annual and inter-annual variations in the vegetation coverage of the Rear Urad county and the patterns of the changes by using the NDVI data from 1996 to 2015 in the past 20 years and the data of average annual precipitation and monthly precipitation,annual mean temperature,and monthly temperature over the past 20 years in Rear Urad County,Inner Mongolia.Additionally,the residual analysis method was used to study how human activities and climate change effect the vegetation and contribution of single element to the change in vegetation.The main conclusion of this study can be summarized as:1.Due to human activities,living cattle and climate change,the coverage rate of vegetation in Rear Urad County is gradually deteriorating from the initial lush stage.However,by the time of 2006,the government issued effective policies to rectify the local ecological environment and protect the vegetation.The restoration of pastures in the local pastures has greatly improved the coverage of the vegetation,and the fluctuation of vegetation coverage as a whole has been slightly larger in the past two decades.The linear trend of the average vegetation coverage in spring,summer,autumn and winter during the year is positive.The results of the study showed that the vegetation of the Rear Urad County was mostly centered in the southeast,that is,in the Hetao Plain,south of Yinshan Mountains,and it was high in the southeast and northwest in the southwest.2.According to the temperature and rainfall data of the Rear Urad Rear County,the two parameters of temperature and rainfall are interpolated by local thin disk spline smooth function method.And using the linear regression method to analyze the temporal and spatial changes under climate factors and rainfall factors from 1996 to 2015 in Rear Urad County.The annual precipitation declines insignificantly,moreover the amount of rainfall in spring,summer and autumn seasons also show an inessential downward trend.In contrast,the downtrend of precipitation in summer is much larger.Annual average temperature in Rear Urad County,however,shows a significant upward trend and the average temperature in the four seasons is increasing.Temperatures in spring and summer reached a significant(p<0.01)upward trend.The climate tends to be slightly warmer.3.According to the temporal and spatial characteristics of vegetation coverage and climatic factors in the Urad Rear Banner of the study area,the vegetation type scale was used to conduct partial correlation analysis between the vegetation coverage in the inter annual and seasonal variation of the study area and the climatic factors in the corresponding time period,and the vegetation cover was studied.The correlation between climatic factors and the two,and the degree of response between the two.At the same time,the correlation between the vegetation coverage of the Urad Rear Banner and the climatic factors in the previous season was analyzed to compare the lag time of the climatic factors with the growth trends of the vegetation in the previous and current research regions.The results of the study showed that the overall vegetation coverage of the Urad Rear Banner from 1996 to 2015 was on the upward trend,with bare land and micro-vegetation coverage significantly decreasing,and low vegetation coverage and high vegetation coverage slowly increasing,showing a gradual increasing trend and presenting southeast The coverage of the Ministry is high in the northwest;the climate change makes the vegetation growth period of the Urad Rear Banner show a prolonged trend;the vegetation growth of the Urad Rear Banner has a negative correlation with the annual average temperature,and shows a significant positive correlation with the annual average precipitation.The correlations are not significant in relation to annual average wind speed,average annual sunshine duration,and annual average humidity.4.1n the study,the residual analysis method was used to quantitatively analyze the response of vegetation changes in the Urad Rear Banner to climatic factors and human factors,and to study the contribution of climate and human factors to the impact of vegetation changes.The results show that the residual value of vegetation coverage between 2007 and 2015 is positive,and there is a non-significant upward trend,indicating that Urad Rear Banner improved the coverage of vegetation coverage due to human factors,and the growth of vegetation exists.Good effect.The research results show that the contribution of human factors to the impact of vegetation cover changes in Urad Rear Banner is about 45%,while the contribution of climate factors to the impact of vegetation cover changes is 55%.The reduction of vegetation often presents many problems to the ecology.As people attach more importance to the environment,for a city,vegetation is an indispensable and important element in its ecosystem,and it is indispensable for the protection of the region's ecological environment.The important role of neglect,through the study of vegetation coverage,can understand the local environmental conditions and timely grasp the dynamic changes in the ecological environment of the study area.Therefore,the use of remote sensing images and GIS technology to calculate the vegetation coverage has an important significance for the effective study of the vegetation coverage changes in the Urad Rear Banner.