Optimal Land Use Structure for Sustainable Agricultural Development——A Case Study in Changsha County,South Central China

Environmental and social problems caused by overfertilization,excessive pesticides,and encroachment on farmland are increasingly serious in agricultural settings,especially in suburban agricultural areas and highly intensive agricultural areas.Hence,modern agriculture not only pursues economic benefits,but it also pays more attention to ecological functions and social stability.This paper proposes a set of methods which are designed to realize optimal agricultural benefits and sustainable development by scientifically adjusting the land use structure.Taking Changsha County in South Central China as a case study,this paper first built an index system and adopted the information entropy-TOPSIS method to assess the economic,social,and ecological benefits of agricultural land use.Next,a coupled coordination model and an obstacle model were chosen to diagnose those factors that remained as obstacles to achieving the sustainable and coordinated development of the benefits of agricultural land use.Finally,based on the analysis of the changes in the benefits and obstacles over time,socio-economic and ecological constraints were established,and the multi-objective linear programming method(MOLP)was used to determine the comprehensive benefits and optimal land use structure.The results indicate that:(1)The agricultural benefits were stably increasing from 0.20 in 1996 to 0.79 in 2016.(2)The economic benefit index is no longer the main obstacle,while the social benefit index,which includes components such as the food security index,has become the principal influencing factor.(3)The optimal land use structure and comprehensive benefits were presented by taking into consideration the economic development,environmental protection,and social needs.This study emphasizes economic development,but it also seeks coordinated development with comprehensive benefits.The results of the study could provide scientific recommendations for optimizing the agricultural land use spatial patterns and sustainable land use.

Land Use Allocation Based on Interval Multi-objective Linear Programming Model: A Case Study of Pi County in Sichuan Province

Adjusting and optimizing land use structure is one of the essential approaches to solve the conflict between land supply and demand. In this study,an uncertain interval multi-objective linear programming model was established and applied to analyzing the suitability of land use structure in Pi County of Sichuan Province. An adjustment scheme for optimizing land use structure was proposed on the basis of development planning drawn up by the local government. The results are summarized as follows: 1) the optimal adjustment scope for cropland area ranges from 27 976.75 ha to 31 029.08 ha,and the current area is less than the lower limit of the scope; 2) the optimal adjustment scope for garden land area ranges from 4 736.49 ha to 12 967.11 ha,and the current area is less than the lower limit; 3) the optimal adjustment scope for construction land ranges from 7 761.95 ha to 10 393.18 ha,and the current area is greater than the upper limit; 4) the optimal adjustment scope for industry and mining land ranges from 557.29 ha to 693.54 ha,and the current area exceeds the upper limit; and 5) the areas of forest land,grassland and other agricultural land are within the optimal adjustment scope. In order to maximize comprehensive benefit with the limited resources and the demand of sustainable development,the areas of cropland and garden land are supposed to be expanded properly,while the construction land should be controlled and reduced gradually,and the forest land and other agricultural land can be maintained at the current level in short period.

An Uncertain Programming Model for Land Use Structure Optimization to Promote Effectiveness of Land Use Planning

Land use structure optimization(LUSO) is an important issue for land use planning. In order for land use planning to have reasonable flexibility, uncertain optimization should be applied for LUSO. In this paper, the researcher first expounded the uncertainties of LUSO. Based on this, an interval programming model was developed, of which interval variables were to hold land use uncertainties. To solve the model, a heuristics based on Genetic Algorithm was designed according to Pareto Optimum principle with a confidence interval under given significance level to represent LUSO result. Proposed method was applied to a real case of Yangzhou, an eastern city in China. The following conclusions were reached. 1) Different forms of uncertainties ranged from certainty to indeterminacy lay in the five steps of LUSO, indicating necessary need of comprehensive approach to quantify them. 2) With regards to trade-offs of conflicted objectives and preferences to uncertainties, our proposed model displayed good ability of making planning decision process transparent, therefore providing an effective tool for flexible land use planning compiling. 3) Under uncertain conditions, land use planning effectiveness can be primarily enhanced by flexible management with reserved space to percept and hold uncertainties in advance.

Exploring Smart Growth Boundaries of Urban Agglomeration with Land Use Spatial Optimization:A Case Study of Changsha-Zhuzhou-Xiangtan City Group,China

Urban agglomeration is the main spatial organization mode used by the Chinese government to promote the policy of new urbanization strategy.Hence,a better understanding of the urban growth boundary(UGB)has profound theoretical and practical significance regarding sustainable urban development.This study devised a raster-based land use spatial optimization(LUSO)framework,and utilized ant colony optimization(ACO)algorithm to delimit the smart growth boundaries of the Changsha-Zhuzhou-Xiangtan city group(CZTCG)in China.The aim of this study is to design a LUSO model to explore an optimal pattern of urban agglomeration for sustainable growth.Multi growth scenario including a single development center,multipolar development and balanced development patterns are generated by the LUSO model for the year of 2050,and the optimum spatial pattern is chosen based on objectives comparison and the present stage of economic and social development in CZTCG.The main results are listed as the following.1)It is feasible to identify the growth boundaries of the urban agglomeration using the land use spatial optimization model,and the optimal form of the spatial pattern can be defined.2)With the growth trend of the urban agglomeration gradually spreads from a single center to multi-centers and even small towns,the total optimization target performance gradually increases,which means that the traditional pie-shaped development does not meet the maximum comprehensive benefit of the city group.3)Subject to the regional social and economic development stage,absolute fair development or simply developing the central city is not conducive to promoting the coordinated development of the urban agglomeration.Gradient equalization and gradual advancement are the best choice for UGB delineation of urban agglomeration.The findings of this study would be useful to identify the UGB in CZTCG for more sustainable urban development in the future.

Land use optimization for sustainable development of mountain regions of western Serbia

This study analyses the possibilities for optimal land use structure in mountainous areas of rural Serbia, which is faced with problems such as unfavorable terrain characteristics and inadequate land use patterns causing economic underdevelopment and increasing population migration. In the case of a small privately owned farm in Western Serbia, optimal land use pattern is determined using the linear programming model. The objective function-cost-effectiveness or soil erosion reduction, as well as constraints, are formulated using the benefit-cost ratio(BCR) for a 15-year production period and soil losses data calculated using the Universal Soil Loss Equation(USLE). The best results are achieved using the scenario with the aim to minimize soil erosion, considering the BCR in the constraints. This scenario is proposed since it was registered that the benefit for landowners would increase by five times, while the losses of land would decline about 80%. The sensitivity analysis of investments is performed to check whether the price variation affects the cost-effectiveness of proposed land use. Results show that market changes(nine cases are considered) do not lead to significant changes in land use allocation. Proposed land use pattern improves the environmental condition, strengthens the rural economy and thus offers the greatest potential for sustainable development of mountainous rural areas.

Optimization and Regulation Policy for Land Use Changes Based on Low-carbon Emission in Developed Regions of China

Land use and cover change(LUCC) is one of the important causes of the Earth’s carbon cycle imbalances resulting from failure in optimizing land use. The solution to this problem has been the hotspot of research in land and environmental science. We took 'low carbon', 'energy saving' and 'high-efficiency' as the goals of land use optimization,and integrated Markov-CA(Cellular Automaton),the Grid-Fractal model and GIS,in order to study carbon emission objective function,to establish a simulation method for land use spatial allocation optimization,to evaluate the effect of the method on carbon emissions. Regulation policy on three types of land use spatial allocation was proposed,including 'low-carbon type', 'low-carbon-economic type' and 'economic type'. We applied the method to analyze the land use spatial allocation in Taixing City of the 'Yangtze River Delta' regions in China,and obtained the following results:(i) The three optimization types would improve carbon emissions by 3. 21%,1. 80% and 0. 36% respectively in 2020,compared with 2010;(ii) The actual planning for 2020 was close to the 'low-carbon-economic type';(iii) The optimization method and regulation policy,combining local optimization and global control,could meet the sustainable multi-objective requirements for low-carbon constraints of land use spatial allocation. The result of this research could also serve as a reference for exploration into patterns of regional low-carbon land use and measures for energy saving and emission reduction.

Integrated Approach to the Vital Mechanism Theory and Ant Colony Algorithm for Optimized Land Use Allocation: A Case Study of the Liangjiang New Area in Chongqing

Optimal allocation of land use is essential to promote regional economic and social development.However,research on such allocations in development zones is limited.This paper proposes a new land use allocation method for development zones and tests its feasibility.Based on prior research,this study predicts the developmental stage of a development zone and sets the objective functions and constraint conditions accordingly.This paper then measures the conversion relationship between the land use types in an unit according to the land use suitability results and the vital mechanism theory and uses the ant colony algorithm to construct a land use optimization model on the basis of this conversion relatonship.The model is then applied successfully to a case study of the Liangjiang New Area,Chongqing,China.The results show that the vital mechanism theory better reflects the relationship between land use types.The economic benefits increase 3.5 times and compactness improves by 46.5%between the initial year(2009)and the optimized year(2020),after the proposed model is applied.

Current Research Situations,Problems and Recommendations of Land Use Structure and Layout Optimization

Land is the foundation for human survival and development,and all human social and economic activities are inseparable from the land as a space carrier.With the continuous development of China's social economy,China is facing new social development needs such as urban-rural integration and rural revitalization.At the same time,China starts to attach great importance to ecology and has proposed the concept that lucid waters and lush mountains are invaluable assets.In this situation,the rational use of land resources,the optimization of land use structure and layout are also facing new challenges and problems,and more comprehensive consideration is required to make relevant optimization.Using the method of literature comparative analysis,from the conceptual connotation,basic theory,method model,and specific practice of land use structure and layout optimization,this paper analyzed and summarized the current research situations and problems,and finally came up with recommendations for the future research.

Sustainability Assessment and Land Use Optimization of Oasis Agro-economic System Based on Emergy Analysis

Oases are important habitats for human survival and development in northwest arid China;however, they are fragile. To realize ecological construction and sustainable development in northwest China, an analysis of the economic and ecological benefits of the oasis system with a focus on sustainability and land use optimization of oasis agro-economic systems are needed. This paper selects Fukang City as a study area. It is located on the northern slope of Mt Tianshan, Xinjiang Uygur Autonomous Region. The authors discuss the ecological and economic benefits of the oasis system, annual variation and establish an optimized allocation scheme of oasis land use structure in Fukang City based on emergy analysis and linear programming modeling. From 1996 to 2006 the oasis system was in a weak sustainable development state. Ecological and economic benefits analysis of the oasis system based on emergy analysis shows that the development of an oasis system in Fukang City is restricted by land, climate and water resources, being a typical example of the high-input and low-output type. The comparative advantage analysis of oasis cropping based on economics and ecological economics shows that the farming structure will vary across different goals. If the maximum ecological efficiency is pursued, farming structure is determined by emergy density;and if the maximum ecological and economic benefits with limited water resources are pursued, farming structure is determined by the emergy value per unit area of irrigation.

Towards the sustainable intensification of agriculture——a systems approach to policy formulation

The sustainable intensification of agriculture involves providing sufficient food and other ecosystem services without going beyond the limits of the earth’s system.Here a project management approach is suggested to help guide agricultural policy to deliver these objectives.The first step is to agree measurable outcomes,integrating formal policy goals with the often much less formal and much more diverse goals of individual farmers.The second step is to assess current performance.Ideally,this will involve the use of farm-scale metrics that can feed into process models that address social and environmental domains as well as production issues that can be benchmarked and upscaled to landscape and country.Some policy goals can be delivered by supporting ad hoc interventions,while others require the redesign of the farming system.A pipeline of research,knowledge and capacity building is needed to ensure the continuous increase in farm performance.System models can help prioritise policy interventions.Formal optimization of land use is only appropriate if the policy goals are clear,and the constraints understood.In practice,the best approach may depend on the scale of action that is required,and on the amount of resource and infrastructure available to generate,implement and manage policy.