A Study On Temporal And Spatial Evolution And Mechanism Of Land Use Structure In The Limited Development Of Ecological Zones In Ningxia

The research of Land Use/Cover Change(LUCC)and its driving force is the key content in the field of regional Land Use/Cover Change(LUCC).With the rapid development of human society and economy,the land use structure is constantly changing,and the driving force of Land Use/Cover Change(LUCC)is more and more strong.Taking the limited development of ecological zones in Ningxia as an example,the paper used 4 Landsat TM images in 2000,2005,2010 and 2015 to interpret and research by ENVI 5.1 and ArcGIS 10.1.The land use types in the study area were classified into 7 categories.Supported by the landscape analysis software Fragstats4.2,this paper explored the evolution characteristics of land landscape pattern of the limited development of ecological zones in Ningxia.And then,Principal Component Analysis(PCA)method and multivariate linear regression model were used to analyze the natural factors,social economic factors and policy factors how to affect the land use change in the study area,which provided the theoretical basis for further optimizing the land use structure.Research results showed that:(1)The land use structure of the limited development of ecological zones in Ningxia has significant temporal and spatial differences.Grassland is the main land use type in the central arid zone,while cultivated land is the main land use type in the loess hilly-gully region.Cultivated land,sandy land and other land in the study area are gradually decreasing,Woodland,grassland and construction land are increasing gradually,Woodland and grassland area increase dramatically,the increasing trend of construction land is relatively stable,water changes unstably,since 2010,water area increases gradually and keeps stably.The main transfer process occurs between cultivated land,construction land,grassland.Woodland and other land.(2)The transfer degree of the land use structure of the limited development ecological zones in Ningxia is less intense,it was the most intense in 2000-2005,and then slowed down gradually.The area transferred out of cultivated land,sandy land and other land is larger than the transfer area,so it's mainly transfer out,cultivated land is mainly converted into woodland and grassland,sandy land and other land are mainly transformed into grassland and cultivated land.The conversion area of woodland,grassland and construction land is larger than the area transferred out,woodland mainly comes from cultivated land,the grassland in the central arid zone mainly comes from sandy land,other land and cultivated land,the grassland in loess hilly-gully region mainly comes from cultivated land,other land and woodland,construction land mainly comes from cultivated land and grassland.(3)The fragmentation of land use in the limited development of ecological zones in Ningxia is becoming more and more serious,the heterogeneity of landscape is increasing,and the land landscape is more and more broken.The landscape heterogeneity of the central arid zone and the loess hilly-gully region is increased,while the degree of landscape fragmentation in the central arid zone tends to decrease,the degree of landscape fragmentation in loess hilly-gully region shows an increasing trend,which shows that the land use types in the central arid zone tend to be more neat and consistent,while the land use types in the loess hilly-gully region tend to be complicated and fragmented,this has to do with the topography and landform of the two regions themselves.(4)Natural factors,such as climate,hydrology,soil,slope and elevation,affect the land use structure of the limited development of ecological zones in Ningxia.Drought agriculture with strong drought resistance is mainly developed in the central arid zone,and forestry and animal husbandry should be developed in loess hilly-gully region.All kinds of land use types are mainly distributed in low slope and low elevation ranges.In terms of socio-economic factors,population growth and rural development are the primary factors affecting the land use structure in the limited development of ecological zones in Ningxia.The social economic development and the urbanization level is the second factors,and the ecological environment is the last factor.Among them,crop planting area has the greatest impact on land use change,which regression coefficient is 1.758;The second most influential factor is agricultural output value,which regression coefficient is 1.649;Afforestation area is the third influencing factor,which regression coefficient is 1.016;Total investment in fixed assets and population density are the fourth and fifth influencing factors,each 1%increase of total investment in fixed assets,0.799%increase of land use degree,each one percent increase of population density,0.693%increase of land use degree;Urbanization rate is also an important index to influence the comprehensive change of land use degree.The water resources in the limited development of ecological zones in Ningxia are relatively lacking,so the weight of its influence on land use is low.Policy factors play a macro-guiding role in land use.