Dynamics And Influencing Factors Of Vegetation Disturbance Index In Resource-based Urban Agglomeration

Vegetation is an important part of ecosystem,and it can indicate the change of ecological environment.Climate and human activities are two of the most important factors affecting vegetation status.The resource-based urban agglomeration area is a typical socio-economic and ecological coupling sensitive area,and the land use and mining development have a stronger impact on the vegetation.The study on the dynamic and influencing factors of the vegetation interference in the resource-based urban agglomeration area can enrich the research on the response of the vegetation in the resource-based city,provide a reference for dealing with the ecological environment problems caused by the development of resources,and have a reference value for formulating reasonable policies protection of resources and environment and The development planning for source.The vegetation disturbance index(VDI)can not only reflect the vegetation dynamics,but also reflect the influencing factors of vegetation.In this paper,the spatial and temporal dynamics of vegetation interference index in growth season in Hohhot,Baotou,Ordos and Wuhai,which are typical resource-based urban agglomeration areas,are analyzed based on the 320 phase mod13q1 evi data from Terra satellite MODIS sensor from 2000 to 2015.The spatial differentiation characteristics of vegetation interference index are described by spatial analysis,centroid analysis and trend analysis.The daily mean temperature and precipitation data of 18 meteorological stations,as well as the distribution of land use and open-pit mines are used as data sources.And the spatial correlation analysis was used to characterize the correlation between climate change,land use and vegetation disturbance index,and the to characterize heterogeneity of impact mechanism.1.vegetation interference index value of 0 is the Open pit mines,and the proportion is increasing from 2005 to 2015,with an increasing rate of 0.17%,mainly distributed in Wuhai City,Ordos and Baotou;0-1 is characterized the negative interference,and the overall proportion is increasing with an increasing rate of6.84%,mainly distributed in Baotou,Ordos and Hohhot;1-positive infinite is positive interference,the area and proportion of1-positive infinity are decreasing as a whole,with a decrease rate of 7.01%,mainly distributed in Ordos City.From 2001 to 2015,the average value of vegetation interference index was 0.5-1.5,showing an increasing trend.According to the analysis of the centroid in 2001-2015,the three-year distribution is close to each other.It can be seen from the profile analysis that the vegetation interference index fluctuates in the East,West,North and South profiles.2.The analysis of slope trend of vegetation interference index from 2001 to2015 shows that the increasing trend is mainly distributed in most of Ordos,the middle of Baotou and the north of Hohhot.The analysis of evi trend from 2000 to2015 shows that the increasing trend is mainly distributed in most of Ordos and Hohhot.Based on the analysis of vegetation interference index trend and evi trend from 2000 to 2015,it can be known that human factors such as afforestation can improve vegetation to a certain extent,and mining development can inhibit it.3.The spatial correlation analysis between the vegetation interference index andthe temperature from 2000 to 2015 shows that the correlation coefficient between the vegetation interference index and the temperature is between-0.81-0.89,and the proportion of the vegetation promoted by the temperature is 78.14%,and the proportion of the vegetation inhibited by the temperature is 19.26%.Most areas in the whole region are not significantly positively correlated or negatively correlated.The correlation coefficient between vegetation interference index and precipitation is-0.97-0.85.The spatial correlation analysis between the vegetation interference index and precipitation in 2000-2015 shows that the proportion of precipitation has inhibition effect on the vegetation interference index is 89.56%,and the proportion of precipitation has promotion effect is 7.8%.From the correlation coefficient significance diagram of vegetation interference index and precipitation,it can be seen that most areas in the region are in extremely significant negative correlation,not significant negative correlation.4.On the scale of urban agglomerations,the land use in the study area changed little from 2000 to 2015,and the proportion of construction land increased was relatively the largest,while that of unused land decreased the most.In 2015,the vegetation interference index 0,0-1,1-infinity corresponds to all land use types;in2000-2015,the change of land use types and the trend of vegetation interference index are not significant.Through the analysis of typical sample buffer zone,the relationship between vegetation interference index and open pit mine is analyzed.It can be seen that within a certain range,the vegetation interference index increases with the distance from the open pit mine.It shows that the open-pit mine has a certain impact on the vegetation interference index.