Spatio-temporal Evolution Of Vegetation Coverage And Its Driving Forces In Taihang Mountains

As the main component of terrestrial ecosystem,vegetation has the functions of soil and water conservation,atmospheric climate regulation and ecosystem maintenance.A great quantity of studies have shown that there is an inevitable relationship between vegetation change and natural and social factors.It has important scientific significance to study the spatiotemporal evolution of vegetation and its driving forces for regional vegetation restoration and ecological environment protection.Based on the GIMMS NDVI data from 1982 to 2015 in Taihang Mountain,combined with potential influencing factors such as temperature and precipitation,this paper systematically analyzed the temporal and spatial distribution and evolution characteristics of vegetation cover,discussed the main driving forces of vegetation cover in the study area,and revealed the correlation between vegetation and main driving forces in different time scales.The main conclusions are as follows:(1)Analyze the temporal and spatial evolution characteristics of vegetation coverage in the study area,and the results showed that: The spatial distribution of vegetation cover in the study area has obvious regional differences,showing the characteristics of low in the north section,high in the south section,and cross distribution of high and low values in the middle section.During the 34 years,the vegetation coverage in the study area showed a fluctuating rising trend,of which the extremely significant increase area accounted for 54.42% were mainly distributed in the north and midwestern parts of the study area,the main vegetation type was cultivated vegetation,and only 2.63% of the areas with a decreasing trend were scattered in cities,towns,industrial and mining areas.The vegetation coverage increases with the increase of slope,but has the opposite relationship with elevation.The growth rate of vegetation in low slope area is higher,and the improvement of vegetation in high altitude area is better.(2)The main driving forces of vegetation cover in 34 years in the study area were explored from the perspective of spatial distribution by using geographic detector and correlation analysis methods.The results show that temperature has the strongest explanatory power,followed by slope aspect,sunshine duration,soil type and precipitation,which all have more than 10% explanatory power,while other influencing factors have less than 10% explanatory power.However,the explanatory power of the interaction of any two factors is greater than that of a single influencing factor.When correlation analysis was used,vegetation cover was negatively correlated with relative humidity,slope aspect,sunshine duration,elevation and population,and positively correlated with other factors.(3)Based on the time series,the relationship between vegetation and meteorological factors in the study area was discussed by using correlation analysis and statistical method.The results show that: Vegetation is positively correlated with temperature and precipitation,and negatively correlated with sunshine hours.In the north of the study area,vegetation is negatively correlated with relative humidity,while in the south of the study area,the correlation is not significant.On the whole,the correlation between vegetation and meteorological factors is not significant,and the impact of meteorological factors on vegetation coverage is lagging.Grassland is mainly affected by temperature and precipitation,and other vegetation types are highly correlated with temperature and sunshine hours.