Study On Varation Mechanism Of Land Use Pattern And Its Optimization Model In Songnen High Plain

Land use pattern is an important element to analyze and explain spatial phenomenon,process and mechanism of regional land use.Land use pattern can influence regional ecological environment.Land use pattern is an important basis for the diagnosis of regional land use.Whereas the existing research on the understanding of connotation of land use pattern,present studies most confined the distribution of quantitative change of certain social and economic attributes of the short term land use,and explained the land use spatial framework,of static macroscopic.On various natural factors and social economic factors,the mechanism of the effect of land use pattern change,stay in driving force analysis and selection index evaluation level.The results have little guidance.Regional food production and ecological safety and social and economic development are threatened.The change characteristics and mechanism of regional land use pattern need to be resolved deeply.In view of this,the optimization target of regional land use pattern based on food production,ecological security and social and economic development.Identifing the decision-making behavior of various land use subjects,and optimizing regional land use pattern,designing and constructing the optimization model of regional land use pattern,and proposing regulation countermeasures of land use pattern optimization model.To provide scientific basis for realizing the sustainable utilization of regional land and social and economic development,and to provide important reference for land use planning.This research takes Bayan County as the empirical study area,using GIS and RS technology,programming by Matlab,and the connotation of scientific problems such as land use pattern and land use pattern optimization model involved in this study are defined.This research puts box-counting dimension model into the field of land use,and uses the second derivative to improve the model.The model realized from traditionally artificial recognize to automatic identification of a major shift in land use pattern on the spatial scale method.This research applies fast Fourier transform improves the wavelet analysis model,explores appropriate time scale of the study of land use pattern change in study area.The model realizes from empirically determined to automatic identification in the change of land use pattern on the time scale method,and then clears the volatility characteristics of land use pattern changes in appropriate in time and space scales.On the basis of the determining optimal spatial and temporal scale,creates database of land use patterns in different time points(1979,1991,2003 and 2015)in the study area,and calculates land use transfer matrix in different periods(1979 to 1991,1991 to 2003 and 2003 to 2015),then measures comprehensive dynamic degree of land use,single dynamic degree of land use and frequency of land use relatively changes in different time points,and estimates land use intensity,land use diversity degree and locational index of land use types in different periods.To reveal the spatial and temporal distribution characteristics and its differentiation laws of land use pattern change in study area from 1979 to 2015,setting up land use information Tupu in Semi-variogram.By using the method of spatial correlation dimension and extended Moore configuration,analyzes and interprets the spatial combinations and mutual relationship of different land use type changes in different periods in study area,and then revealing spatial association relationship in each other and its change law of land use pattern in study area.By using wavelet coherence method,sifting and discriminates the key factors of spatial and temporal differentiation of land use patterns in different periods in study area.By using cross wavelet method,defining the influence of key factors on spatial and temporal changes of land use pattern in different periods,determining the relationship between key factors and various land use types.Analysis the impact of key factors on various land use types,elucidating the mechanism of land use pattern change in study area under the influence of key factors.According to the catastrophe theory,we determined the threshold of land use pattern by the wigwan catastrophe model as the basis of land use pattern optimization.Based on multi-agent improved particle swarm optimization algorithm,we build the optimization model of land use pattern,and determined the reasonable optimal allocation of land use type structure and spatial layout on temporal and spatial in study area,and proposing the optimization schemes of land use pattern in study area.Combined with land planning ideas,structuring the optimization model of regional land use pattern.Feedforward control and process control of land use pattern optimization model in study area,we proposed regulation countermeasures of land use pattern optimization model.There are seven aspects we can conclude from the results.Firstly,the optimal temporal and spatial scale of land use pattern change in study area is determined.On one hand,the spatial scale of land use pattern change can be used as the minimum sample unit to analyze the change of land use pattern as an independent geographical unit.Automatic identification of effectively the optimal spatial scales of land use pattern is 900m×900m.The land use pattern has obvious fractal characteristics in the study area in this scale.On the other hand,in the time zone of land use pattern change in the study area from 1979 to 2015,the optimal time analysis of land use pattern change is 36 years.Land use pattern has obviously volatility characteristics around 12.33.The temporal of study area can be divided into three development stages:the early stages of development from 1979 to 1991,the medium term development from 1991 to 2003,the recent development from 2003 to 2015.The global time scale and the localized time scale of land use pattern changes has a high level of consistency in space in study area.Secondly,the quantitative change characteristics of natural and socio-economic attributes of land use types in the study area are measured,and the spatial combination and relationship distribution characteristics of different land use types in the study area are explained.To begin with,in the year of 1979?1991?2003 and 2015,the main types of land use change dry land,woodland and construction land has undergone an obvious trend of conversion.The results verify the accuracy of the improved wavelet analysis method in the time scales recognition of the change of land use pattern.In addition,there are three action forms that caused the spatial heterogeneity of single dynamic degree of land use,comprehensive dynamic degree of land use,frequency of land use relatively changes,land use intensity,land use diversity degree and locational index of land use types,the one is structure factors,the others are random factors and the interaction of structure factors and random factors.The land utilization procedure is not only affected by natural factors but also by human interferences.The effects are different.The temporal and spatial differences and changes of various natural and socioeconomic factors are different.Last but not the least,land use pattern was manifested as space forces between different land use types,distribution and internal association,which showed the complexity of relationships of spatial associations in study area.The spatial association relationships of land use pattern have the obvious variation,which showed the differences of the competition intensity strength of land use pattern in study area.The spatial contiguity of land use pattern is complex in study area.The highest frequency of land use in the neighborhood type is dry land and forest land.The collection rate of land use pattern increased year by year in study area.The frequency of the land use type occurs around the center grid that dominant land use types in the study area,which closely related to the spatial distribution of land use types.Thirdly,the key factors influencing the change of land use pattern in study area are screened and identified.The influence of various key factors on the temporal and spatial changes of land use pattern is remarkable in study area from 1979 to 2015.There are eighteen key factors which temporal and spatial variation of land use pattern in study area.They are soil organic matter,soil total nitrogen,soil available phosphorus,soil available potassium,soil texture,thickness of plow layer,elevation,geographical feature,NDVI,DVI,year sunshine hours,annual average temperature,annual precipitation,heavy metal pollution,land use intensity,GDP,population,policy and law.The key factors of temporal and spatial changes of land use pattern at different time points are different.The impact of different land use types is significantly different.Especially,the impact of dryland,paddy field,forest land and construction land is most obvious,and the impact of key factors on these four land use types is more significant than the other land use types in the region.Fourth,the effect mechanism of natural factors and human factors on land use pattern change in study area is expounded.On one hand,there are significant differences in the relationship between the key factors affecting the temporal and spatial changes of land use pattern and various land use types,and the effect of various key factors on the temporal and spatial changes of land use pattern is significant from 1979 to 2015.The correlation between key factors and dryland and forest land is strong in 1979.The correlation between key impact factors and dryland,forest land and construction land is strong in 1991 and 2003.The correlation between key impact factors and drylands,paddy field,forest land and construction land is strong in 2015.On the other hand,the effect mechanism of various key factors on the temporal and spatial changes of land use pattern is obvious.Agricultural cultivation dominates in study area in 1979.Agricultural production and economic development dominate in study area in 1991,2003 and 2015.Fifth,the land use pattern of study area is optimized.On one hand,the security threshold of land use pattern in different spatial regions is changed from the safe state to dangerous state gradually.Generally,the current land use of the study area tends to be dangerous.Therefore,the problem of land use pattern security would become more and more serious if we do not take concrete measures to prevent the worsening trend.The adjustment of land use pattern is urgent,and the land use pattern security as the basis of land use pattern optimization.On the other hand,four land use pattern optimization schemes were proposed in the study.Different optimization schemes have different preferences for the decision-making of food production,ecological security,social and economic development of land use pattern optimization.There are different benefits of land use pattern optimization of sub-goals for grain production,land ecological carrying capacity,land ecological compatibility,land use economic output and the total cost of land use type conversion.Various optimization schemes have obvious optimization of the quantitative structure and spatial layout of land use types.Sixth,the optimization model of land use pattern in study area is designed and constructed.The land use pattern optimization model is dominated by group layout.Take the main traffic road as the development axis.Form the spatial structure as 'four development nodes,four development axis and five functional zones'.Construct land use pattern optimization model as 'suitable for cultivating to farm,suitable for planting to plant,suitable for pasturing to pasture,suitable for building to build'.Finally,regulation countermeasures of land use pattern optimization model are proposed.the regulation goals of optimization model of land use pattern are grain production,ecological security and social economic development.From three levels of government agent,department agent and individual agent of land use pattern proposed to optimize the mode of regulation.From five aspects of law,administration,socio-economy,technology and ecology of land use pattern proposed to optimize the mode of protection measures in study area.From aspects of feedforward control and process control to achieve the study area of land use pattern optimization model of regulation.Seeking the harmonious unity of food production,ecological security and social and economic development,to ensure the normal operation of land use pattern optimization model in study area.The results of this research will build a scientific system to safeguard national food security and improve the regional ecological environment,and will provide basis for land use planning,it also has important both theoretical and practical significance to achieve regional sustainable land use and promote sustainable socio-economic development.Besides that,the study on optimization model of land use pattern and its regulation countermeasures in study area will provide reference for related research of similar areas.