Temporal And Spatial Variation And Driving Forces Of Land Use In Hulunber Grassland Area

It is of great significance to study the temporal and spatial variation of land use and its driving mechanism in grassland area for maintaining grassland health,optimizing land management and promoting sustainable development of grassland.This article choose Hulunber grassland area with the typical characteristics as study area,the land use spatial pattern and dynamic changes in the study area from 1990 to 2015 is analyzed,the economic and social and climate database is constructed from 1990 to2019.This research deeply analyzes the driving mechanism of land use change in the study area and identifies the key driving factors combined with traditional statistics and structural equation model.Furthermore,it studies the influence of land use change and grassland utilization on the grassland animal husbandry in Chenbaerhu grassland,and combines the land use change and the grassland animal husbandry management,which puts forward to countermeasures and suggestions for the reasonable planning of land resources in grassland area.The main research conclusions are as follows:(1)From 1990 to 2015,the cultivated land,forest land and artificial surface area increased,while the grassland,wetland and other land use type decreased in Hulunber grassland area.Among them,the cultivated land and forest land area increased greatly,while the other types were relatively few.Grassland decreased greatly from 1990 to 2000,which was 1 309.79 km~2;cultivated land increased greatly from1990 to 2000,which was 1 212.08 km~2;forest area continued to increase;water area decreased significantly from 2000 to 2010,which was 363.76 km~2;artificial surface area increased most from 2000to 2010,which was 162.52 km~2;other land types showed net decrease of 213.15 km~2,which was 21.52%.(2)The driving mechanism of land use change in the research area is the result of the interaction of"regional economy+agricultural and livestock factors+climate change",in which the driving mechanism of agricultural and livestock factors is dominant(path coefficient is-0.84 at most).The driving factors that significantly affect land use change are mainly urbanization rate(the maximum factor load is 0.95),added value of tertiary industry(the maximum factor load is 0.83)and number of live stocks(the maximum factor load is 0.95 and 0.90 respectively).The change of cultivated land and forest were mainly affected by population distribution and structure,grassland was significantly affected by animal husbandry,and building land was significantly affected by urbanization and economic factors.(3)The case study showed that since the implementation of the grassland ecological reward and subsidy mechanism,the grassland area of Chenbaerhu had basically remained stable,with grazing and mowing areas of 83.00×10~4 hm~2?80.29×10~4 hm~2 respectively.The average biomass of grassland and pasture lands increased from 8.72×10~3 kg/hm~2 and 7.68×10~3 kg/hm~2 in 2010 to 12.93×10~3 kg/hm~2 and11.12×10~3 kg/hm~2 in 2019 respectively,and the growth trend of grassland vegetation became better.In2019,all counties in Chenbaerhu except Baorixili reached the balance of grass and livestock.The main reason for the imbalance of grass and livestock in Baorixili were the limited grassland area and the seasonal imbalance caused by the failure of forage grass to meet the demand in winter and spring.(4)The main problems of land use in Hulunber grassland area include grassland degradation,human activity enhancement and wetland atrophy.In view of grassland protection and construction,this paper proposes the spatial layout of"five districts and one belt",combines land use change with grassland animal husbandry management,puts forward targeted sustainable management suggestions and countermeasures,and provides reference for regional land use policy formulation and grassland management.In this paper,the main innovation is overcoming the defects of traditional statistical method based on the structural equation model to research driving mechanism of land use change,at the same time,dealing with latent variables and multiple independent variables and dependent variables.The three driving factors of land use including regional economy,agricultural animal husbandry factor and climate change has been identified clearly under different time and space scales,the causal relationship of different driving factors has been researched quantitatively,which provides a new perspective and breakthrough point to study driving force of land use change in grassland area.