Distribution Pattern And Controlling Factors Of Deciduous Broad-leaved Forest In China

Deciduous broad-leaved forest is an important zonal vegetation in China.Studying the distribution pattern of deciduous broad-leaved forest in China and analyzing the control factors affecting its distribution can provide important reference for vegetation regionalization,planning and ecological construction,and is of great significance to the protection,restoration and reconstruction of mountain vegetation.In this paper,based on the national land cover data,China’s annual vegetation index(NDVI)spatial distribution data and climate data(temperature,precipitation),and widely collected at home and abroad published on deciduous broad-leaved forest research related books,journal papers and other information,using literature retrieval method,center of gravity migration model analysis,correlation analysis and regression analysis,using Arc GIS,Matlab and SPSS software,study the horizontal and vertical distribution pattern of deciduous broad-leaved forest in China,and analyze the main control factors affecting its distribution.The main conclusions are as follows:(1)Deciduous broad-leaved forest has the largest distribution area in Northeast China,accounting for about 36.69%,and Heilongjiang Province accounts for about21.02%.The proportion of North China ranks second,about 21.85%,and Inner Mongolia Autonomous Region accounts for the largest proportion,about 14.25%.Southwest,northwest and south-central regions accounts for about 13.77%,13.17% and11.17%,respectively.East China accounts for only 3.29%.(2)From 2001 to 2015,the distribution center of the deciduous broad-leaved forest in the middle temperate zone moves northwestward,with a migration distance of about47.98 km and a migration angle of clockwise about 359.02° starting from the north coordinate.The distribution center of the deciduous broad-leaved forest in the warm temperate zone migrats northeastward,with the migration distance of about 44.86 km and the migration angle of about 1.11°.The distribution center of subtropical deciduous broad-leaved forest migrates northeastward,with the migration distance of about48.56 km and the migration angle of about 1.39°.(3)The upper and lower elevation ranges of vertical distribution of deciduous broad-leaved forest in China are 400-3000 m and 54-2300 m,respectively.In the third step,the relative contribution rate of latitude to the vertical distribution boundary of deciduous broad-leaved forest is the largest,which is the dominant factor.In the first and second step,mountain base height(mountain effect)plays a leading role.(4)The proportion of areas with weak correlation between NDVI value and annual average temperature in deciduous broad-leaved forest in China is about 65.38%,moderately positive correlation is about 23.27%,highly positive correlation is about8.62%,and moderately negative correlation is about 2.58%.The proportion of area with weak correlation between NDVI value of deciduous broad-leaved forest and annual precipitation in China is about 70.88%,with moderate positive correlation of about5.70% and moderate negative correlation of about 18.16%.(5)The mean temperature and annual mean temperature of the coldest month(January)in the vertical distribution of deciduous broad-leaved forest are-17.6-1.02°C and 2.32-13.86°C,respectively.From southeast to northwest,with the increase of latitude,and the terrain transited from the third step to the second step,with the increase of altitude,the mean temperature and annual mean temperature of the coldest month(January)gradually decrease.The mean temperature of the hottest month(July)is15.25-25.31°C.The average annual precipitation in the vertical zone of deciduous broad-leaved forest is 157.97-1879.85 mm.From the southeast coast to the northwest inland,the precipitation gradually decreases.