Spatio-temporal Pattern Evolution And Driving Forces Of Net Primary Productivity Of Vegetation In Guangdong Province From The Perspective Of "Production-Living-Ecological Space"

Guangdong Province is one of the most economically developed provinces in China,and also one of the provinces with the most obvious regional differences.Studying the spatial and temporal variation patterns of vegetation Net Primary Productivity(NPP)in this region from the perspective of"Production-Living-Ecological space"and the driving forces behind them can provide an in-depth understanding of how the degree of human activities affects the regional differences of ecological and environmental problems in Guangdong Province,further understand the carbon sink pattern in Guangdong Province,and provide a scientific basis for promoting the construction and sustainable development of ecological civilization in Guangdong Province.This paper provides a scientific basis for promoting the construction and sustainable development of ecological civilization in Guangdong Province.In this paper,based on the climatic and NDVI data within Guangdong Province,a Carnegie-Ames-Stanford Approach(CASA)model is used to estimate the long time series vegetation NPP in Guangdong Province from 2000 to2020,analyze its temporal and spatial variation patterns and explore its influencing factors using a geographic probe.Based on the topographic,meteorological,vegetation and land use data,we delineated the"Production-Living-Ecological space"in Guangdong Province,representing the regional differences in the degree of human activities in Guangdong Province,and conducted a zoning study to further explore the spatial and temporal evolution patterns of vegetation NPP and the influencing factors under different degrees of human activities.The results of the study are as follows:(1)The"Production-Living-Ecological space"in Guangdong Province is dominated by"ecological space",with an area of 128962.02km~2,accounting for about72.4%,mainly distributed in the north and east of Guangdong."Living space"is the least distributed,with an area of 9609.54km~2,accounting for about 5.4%,which is mainly distributed in the Pearl River Delta(PRD)region.The"production space"covers an area of 39,487.55 km~2,accounting for about 22.2%.It is mainly distributed in the"living space"around the the PRD region,and has contiguous distribution in the flat areas of East,west and North Guangdong.(2)Most of the regions in Guangdong Province have good vegetation growth and high vegetation NPP values,with an overall distribution trend of medium-low week-high.2000-2020 showed a fluctuating growth trend of vegetation NPP in Guangdong Province,with a multi-year average vegetation NPP value of 833.55 g C/(m~2·a)in 21 years,the lowest vegetation NPP value of 640.84 g C/(m~2·a)in 2004,and the highest vegetation NPP value of 881.15 g C/(m~2·a)in 2016.640.84 g C/(m~2·a)in 2004,and the highest vegetation NPP value of 881.15 g C/(m~2·a)in 2016.(3)In terms of"three-life space",the annual mean vegetation NPP value of"ecological space"in Guangdong province was the highest,which was1016.82g C/(m~2·a).This was followed by"production space",with an average annual vegetation NPP value of 813.28g C/(m~2·a).The average annual vegetation NPP value of"living space"was the lowest,511.41g C/(m~2·a).The lowest NPP values of"three living space"vegetation all appeared in 2004,the highest NPP values except"living space"appeared in 2017,and the other two types of space appeared in 2016.(4)The spatial differentiation influence factors of vegetation NPP were detected by using geographic detectors,and the results showed that the vegetation NPP in Guangdong Province was strongly influenced by land use type,elevation,slope,soil type and population density,and less influenced by per capital GDP,road network density and night lighting,and slope direction had almost no influence on vegetation NPP.(5)Spatial differentiation factors of vegetation NPP in different spaces of Guangdong Province are different.The results of the geodetector detection of vegetation NPP in the"Production-Living-Ecological space"show that in the"production space",vegetation NPP is strongly influenced by land use type,soil type,per capital GDP,road network density,and the slope direction.In the"production space",vegetation NPP is strongly influenced by land use type,soil type,per capital GDP,road network density,and less influenced by population density,night lighting,and elevation slope.In"living space",vegetation NPP is strongly influenced by land use type,soil type,population density,night lighting,per capital GDP,and road network density,and less influenced by elevation and slope.In"ecological space",it is strongly influenced by elevation and land use type,and less influenced by slope,soil type,population density,night lighting,per capital GDP,and road network density.The influence of slope direction on vegetation NPP in each space is negligible.(6)Comparing the q-values of geographic exploration results of"Production-Living-Ecological space"in Guangdong Province,it is found that vegetation NPP in"production space"and"living space",where human activities are more intensive,is mainly affected by human activities.And in"ecological space"is mainly influenced by topography,the q-values of elevation,slope and slope direction are higher than those in"production space"and"living space".