West China provides important ecological services to the rest of the country, and has attracted great attention because of its serious ecological degradation and frequent natural disasters, and its strong connection with the industrial and economic development in East China. In order to strengthen ecological restoration and promote sustainable economic development in West China, the Chinese government adopted the Western Development Policy, which offered financial aid to and initiated a large number of projects in the region. Although many previous studies have emphasized the positive effects of ecological restoration in West China on ecological security and sustainable development of China, relatively less attention has been paid to analyzing multiple conflicts related to sustainable development in the region. This paper examines the main development goals and interests that have caused these conflicts. The authors suggest that integrated conflict management should be carried out for the sustainable development in West China.
The Grain-for-Green Policy aims to convert cropland to grassland and forest across western China, and evaluating ecological risk is essential to its implementation. Because few recent studies have focused on eco-risk changes of land use in the areas affected by significant policies, this paper took Zhengning County in Gansu Province as our focal area, and studied spatial-temporal changes in ecological risk before and after policy implementation. Based on indices of landscape fragmentation and ecosystem service value, an ecological risk assessment method using ArcGIS and Fragstats was done. The regional gravity center model and land spatial distribution model were also used to enrich the quantitative description of divisional eco-risk and its spatial-temporal variation in the county. Results showed that the implementation of the policy has contributed to an overall reduction in ecological risk in Zhengning County, with a divisional degree order reduction following the pattern： eastern Zhengning 〉 western Zhengning 〉 central Zhengning. The gravity center for eco-risk shifted 4288 m southwest from 1995 to 2010 due to landscape fragmentation. The study implies that greater attention should be paid to forest and grassland restoration in eastern Zhengning, cropland protection in central Zhengning, and soil and water conservation in western Zhengning.
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.
How to coordinate arid eco-environmental protection and oasis agricultural development and avoid desertification is a key problem in achieving the sustainable development of oasis human- earth systems. We analyzed the temporal characteristics and overall tendency of an arid oasis agricultural production system in Yining County, China by means of emergy methods and ternary diagrams theory. From 1989–2008, total emergy input and output of the oasis agricultural system in Yining County had a trend of sustainable development. According to the sustainability analysis with emergy indices, the agricultural production systems in Yining County were still at a sustainable status. However, the emergy-based sustainability index （ESI） followed a decreasing trend. Scenario analysis of the sustainability lines based on ternary diagrams showed that both the F （input from economic component） and N （input from nonrenewable resource） leading modes had limitations in the study case. The agricultural production of Yining County should adopt the R leading mode, in which the percentage of non-renewable resources in the local system will be kept roughly unchanged, while the fraction of purchased inputs and renewable resources will be decreased in synchronism. In this way, the contribution from local renewable resources to agricultural production will be increased, and sustainable development ensured.
