Uphill or downhill?Cropland use change and its drivers from the perspective of slope spectrum

The continuous decrease of low-slope cropland resources caused by construction land crowding poses huge threat to regional sustainable development and food security.Slope spectrum analysis of topographic and geomorphic features is considered as a digital terrain analysis method which reflects the macro-topographic features by using micro-topographic factors.However,pieces of studies have extended the concept of slope spectrum in the field of geoscience to construction land to explore its expansion law,while research on the slope trend of cropland from that perspective remains rare.To address the gap,in virtue of spatial analysis and geographically weighted regression(GWR)model,the cropland use change in the Yangtze River Basin(YRB)from 2000 to 2020 was analyzed and the driving factors were explored from the perspective of slope spectrum.Results showed that the slope spectrum curves of cropland area-frequency in the YRB showed a first upward then a downward trend.The change curve of the slope spectrum of cropland in each province(municipality)exhibited various distribution patterns.Quantitative analysis of morphological parameters of cropland slope spectrum revealed that the further down the YRB,the stronger the flattening characteristics,the more obvious the concentration.The province experienced the greatest downhill cropland climbing(CLC)was Shannxi,while province experienced the highest uphill CLC was Zhejiang.The most common cropland use change type in the YRB was horizontal expansion type.The factors affecting average cropland climbing index(ACCI)were quite stable in different periods,while population density(POP)changed from negative to positive during the study period.This research is of practical significance for the rational utilization of cropland at the watershed scale.

Welfare effects of rural-urban land conversion on different aged land-lost farmers:exemplified in Wuhan city

Rural-urban land conversion is a universal phenomenon in the rapid process of economic development and urban growth.The welfare of farmers who lost their farmland attracted a widespread concern within the society and academia.However,further research about differentiated policies according to the characteristics of different farmer groups is still need to be conducted.This article divides the land-lost farmers into three age groups:younger than 45,45-65,and more than 65.It proposes a welfare index system including eight functional areas based on different age groups of affected farmers,taking four districts of Wuhan City as case study area.Fuzzy mathematics method is used to derive the aggregated welfare effect index.Our analysis show that the overall welfare levels of land-lost farmers of all age groups declined,but with a varying degree,with the level of welfare in those farmers who are 45-65 years old,younger than 45 years old,and older than 65 years old decreased by 18.7%,16.6%,and 12.7%,respectively.The direction and degree of effects on the functional activity index varies among different groups.Economic conditions,living environment,health,and social participation of all age groups decrease while social security and housing conditions increase.On the other hand,development opportunities,social communication,and leisure have different changing directions in different age stages.These results call for differentiated and tailor-made compensation policies for land-lost farmers,towards improving the welfare levels of all farmers and reduce the disparity among them.

Life satisfaction approach to farmers' compensation for land acquisition:empirical study from the suburbs of Wuhan City

Farmers' compensation for land acquisition is not only critical to increasing their income and to playing a pivotal role in maintaining rural stability,but also to the promotion of sustainable land use.Based on analysis of Chinese land acquisition policy under the Land Management Law,which provides principles or guidelines for determining compensation according to agricultural land use in regard to farmers' previous quality of life,the Life Satisfaction Approach is introduced in this article to evaluate farmers' compensation for land acquisition.Employing data from a questionnaire survey on 346 farming households in Wuhan Suburbs,this article examined the influence of farmland on farmers' life satisfaction and evaluated the level of compensation for land acquisition.Results show that farmland has a significantly positive impact on life satisfaction,which fell by 0.033 on a five-point scale following a reduction farmland by of 1 mu.Respondents were willing to accept approximately RMB 3066.44 annual household income for the loss of 1 mu farmland;the level of compensation after discounting by 6.2%is RMB 750,000 per hectare.It was found in a further comparative study that the level of farmers' compensation for land acquisition is decidedly low,and it was also shown that their compensation standards,as well as the actual compensation,could be substantially improved by expanding economic compensation to non-economic compensation to embody farmland multifunction in terms of production and non-production against farmers' previous quality of life.This article proposes a compensation model that enriches the content of land acquisition compensation,extends the current literature on measuring compensation,and provides economic theory bases for increasing compensation standards and improving policies related to land acquisition.We consider that if this compensation model is applied,it could raise the cost of land acquisition and improve usage of land,reduce the speed of rural-urban land conversion,and improve farmers' well-being.

Analysis of the Management Policy and Comprehensive Benefit of Agriculture in the Rural Area:A Case Study on Pujiang County,China

To solve the problems of the poverty in rural areas and raise the output efficiency of agriculture,policy is the primary factor. Guiding by good policies,the design of agricultural structure and management technology are the two main technical supports for agricultural development. The authors apply the model to determine the consequences of four so-called poverty alleviation strategies:(i) intensification of production,(ii) diversification of livestock production,(iii) land expansion,and (iv) an exit from agriculture,with a set of regional poverty and biodiversity indicators. Diversification seems to be the most promising poverty reduction strategy,but requires an efficient use of animal manure in cropping systems to avoid environmental problems. Improved nutrient management in cropping systems is effective in reducing the regional nitrogen surplus,but less effective in increasing per capita income. The exit strategy is beneficial for reducing poverty and achieving biodiversity goals,but may have important social consequences,which are not addressed in this study. Further reduction of rural poverty is hampered by labor constraints during the harvesting period of high value crops,such as vegetables and fruits,which calls for research and development in the field of agricultural mechanization.

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.

Welfare Balance of Different Interest Groups During Rural-urban Land Conversion

Rural-urban land conversion is currently a common social economic phenomenon during the process of economic development and rural urbanization in China. Rural-urban land conversion is positively effective as far as social and economic benefits are concerned (Yang, 2002), but its negative effect is also evident, resulting in such problems as low efficiency of rural land configuration and loss of social welfare. Consequently, farm-ers should also have an equal chance to enjoy the social welfare enhanced by land conversion. Based on the theories of welfare economy, this paper puts forward policy suggestions by discussing the welfare changes of various interest groups, builds the model of welfare distribution, and analyzes the conditions of maximizing social welfare. The absolute and opposite value of social welfare is closely related with the speed of rural-urban land conversion, and governments should give farmers and collectives fair compensa-tion to make up for the utility loss caused by land expropriation, which are conclusions drawn from this paper. This study aims to provide a theoretical basis for regulating targets and evaluation criteria, realizing the mechanism and implementation of public po-lices during rural-urban land conversion.

Performance Evaluation of Land Use Regulation

This article makes a quantitative study on economic performance of arable land protection and land use regulation with dummy variable model.It is shown that land use regulation is favorable for economic growth and protection of arable land and that there are still some problems in the implementation of land use regulation.Thus,it puts forward corresponding suggestion.

Multi-objective Programming and Social Welfare Analysis of Rural–urban Land Conversion Decision-making

Rural–urban land conversion is an inevitable phenome non in urbanization and industrialization. And the decision-making issue about this conversion is multiobjective because the socia decision maker (the whole of central government and local author ity) has to integrate the requirements of different interest groups (rural collective economic organizations, peasants, urban land us ers and the ones affected indirectly) and harmonize the sub-objects (economic, social and ecological outcomes) of this land allocation process. This paper established a multi-objective programming model for rural–urban land conversion decision-making and made some social welfare analysis correspondingly. Result shows tha the general object of rural–urban land conversion decision-making is to reach the optimal level of social welfare in a certain state of resources allocation, while the preference of social decision makers and the value judgment of interest groups are two crucia factors which determine the realization of the rural–urban land conversion decision-making objects.

Evaluation of Intensive Land Utilization based on Anti-planning Concept

Based on the gist of anti-planning,evaluation standards and methods of intensive land utilization were re-examined according to the inverse planning procedures.Significant role of compulsory non-development zone(similar to the traditional"non-construction land")among the planning fruits in the intensive utilization of urban land resources and relevant index weights in the evaluation system were re-weighed.In land evaluation,relevant control indexes of compulsory non-development zone were first calculated and evaluated,healthy and sustainable development coefficients of land were obtained and regarded as the core content of the whole evaluation system.

Agricultural land loss in China's urbanization process

In China, urbanization of agricultural land around city agglomerations increases rapidly. Rapid urbaniza-tion of agricultural land affects food supply, land value and ecological balance in the society. In China, the urban built-up area had increased by 40% from 1996 to 2003. This increase came predominantly from farmland surrounding thecities. How the ongoing urbanization of China affects its agricultural land is the focus of this paper. In current studies, wehave found that population density; urbanization degree and personal income are key factors that influence the urbaniza-tion process. Based on this, relation model has been established and to predict the general trends of the urban areaexpansion in China in 2020. In 2020, the constructed urban area of China would be increased by 1.3 times compared with2003. In 2020, this study anticipates the conversion of about 32,562 sq. km. agricultural land of China for urban use.

Non-agricultural Population, Employment and Land:An Econometric Study in an Integrated Framework

This paper explored the relationships among non-agricultural population, employment and land in an integrated framework, taking account of rural-urban land conversion into Carlino-Mills's model on the regional growth. Two-stage-least-squares and ordinary-least-squares were employed. Recent data for district (grade) cities in China (from 1999 to 2005) were used. Our results showed that: first, urban population in-fluenced non-agricultural employment, and vice versa, but the evidence that non-agricultural employment influenced urban population was stronger than the evidence that urban population influenced non-agricultural employment; second, urban popula-tion and nonagricultural employment both influenced rural-urban land conversion, but the evidence that urban population influenced rural urban land conversion was more stronger than the evidence that non-agricultural employment did. We also found that: first, the employment from the secondary industry influenced urban population in a positive way, and vice versa, but the employment from the tertiary industry influenced urban population in a negative way, and vice versa; second, the em-ployment from the secondary industry influenced rural-urban land conversion in a positive way, but the employment from the tertiary industry influenced rural-urban land conversion in a negative way. We can conclude that the key of urbanization is to speed up the process of non-agricultural employment, espe-cially the employment from the tertiary industry, which might promote non-agricultural population, employment and land har-moniously.

Analysis of the Impact of the Growing Area of Food Crops on Farmers' Income in Yunnan Province

As a major agricultural province,Yunnan has always attached great importance to food production,and the proportion of the growing area of food crops to the growing area of total crops is more than one half in Yunnan Province,but the grain production efficiency has been low in recent years.Therefore,under the guidance of stabilizing food production and adjusting structure proposed by Yunnan provincial government,we analyze the impact of the growing area of food crops on farmers' income,based on the recent trends of the growing area of food crops.Finally we put forth the following recommendations:developing the food production based on market; rationally making overall arrangement of planting structure; paying attention to the agricultural science and technology progress.

Dynamics of the eco-environmental quality in response to land use changes in rapidly urbanizing areas: A case study of Wuhan, China from 2000 to 2018

The dramatic land use changes that occur in rapidly urbanized areas are important inducement to changes in the eco-environmental quality.Investigating urban land use changes and their eco-environmental quality responses can provide theoretical support and a decision-making basis for sustainable and high-quality development in rapidly urbanizing areas.Taking Wuhan,China,as the study area,this paper extracts land use information using Landsat satellite remote sensing images and a support vector machine classification.Based on this,a remote sensing-based ecological index evaluation model including humidity,greenness,dryness and heat is constructed to explore the changes in land use and their eco-environmental quality responses from 2000 to 2018.The results show that(1)the structure,extent and spatial layout of land use in Wuhan from 2000 to 2018 have undergone tremendous changes under rapid urbanization,and the change of construction land is the greatest among all land use types;(2)the overall quality of eco-environment in Wuhan continues to improve as the scale of the improved eco-environment areas is greater than that of the deteriorated areas.The direction and magnitude of the impact of each indicator on the eco-environmental quality are different;(3)the improvement or deterioration of eco-environmental quality is closely related to the changes of different land use types within the study area.The eco-environmental quality shows significant spatial heterogeneity,especially between the main urban areas and the suburban areas.This paper argues that reasonably adjusting the land use structure can serve to maintain or even improve the quality of the regional eco-environment.Finally,this study puts forward suggestions for the coordinated development of land use and the eco-environment in rapidly urbanizing areas.

Simulating Sustainable Urban Development by Incorporating Social-ecological Risks into a Constrained CA Model

A key solution to urban and global sustainability is effective planning of sustainable urban development, for which geo-techniques especially cellular automata(CA) models can be very informative. However, existing CA models for simulating sustainable urban development, though increasingly refined in modeling urban growth, capture mostly the environmental aspect of sustainability. In this study, an adaptable risk-constrained CA model was developed by incorporating the social-ecological risks of urban development. A three-dimensional risk assessment framework was proposed that explicitly considers the environmental constraints on, system resilience to, and potential impacts of urban development. The risk-constrained model was then applied to a case study of Sheyang County, Jiangsu Province in the eastern China. Comparative simulations of urban development in four contrasting scenarios were conducted, namely, the environmental suitability constrained scenario, the ecological risk constrained scenario, the social risk constrained scenario, and the integrated social-ecological risk constrained scenario. The simulations suggested that considering only environmental suitability in the CA simulation of urban development overestimated the potential of sustainable urban growth, and that the urbanization mode changed from city expansion that was more constrained by social risks to town growth that was more constrained by ecological risks. Our risk-constrained CA model can better simulate sustainable urban development; additionally, we provide suggestions on the sustainable urban development in Sheyang and on future model development.

发展地理学研究进展与展望

In this paper,we review the research progress in development geography since the 20th century,focusing on its connotation and theory,fields,methods,and development trends.Specifically,we systematically review the research and applications of development geography,comprising fields such as the convergence of underdeveloped countries and regions,and the convergence of the process of improving the quality of life in developed countries and regions.Then,based on an analysis of research progress in development geography in foreign countries,we examine the development conditions and disciplinary advantages of development geography in China.Further,we highlight that future development geography research in China should focus on the latest international academic research and China’s national macro-strategic needs.Future research in development geography should be guided by the theory of sustainable development,the core of which is to improve sustainable livelihood capacity and regional green development levels in underdeveloped regions.This core includes the construction of industrial policy and development geography theory,as well as an interdisciplinary integrated research system.The focus must be placed on researching the spatial patterns,diffusion characteristics,and the convergence mechanism of regional development.Such a focus will facilitate exploration of the regulatory policies and scientific paths that serve regional economic construction and industrial development.