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.

Research on Environmental Impact Assessment Methods of Farmland Improvement along Coastal Areas of Jiangsu Province

[ Objective] The study aimed to assess the impact of farmland improvement on ecological environment along coastal areas of Jiangsu Province. [ Method] Taking the coastal farmland improvement of Sheyang County, Jiangsu Province as an example, an indicator system of environ- mental impact assessment （EIA） for coastal farmland improvement was established based on data collection, field survey and monitoring results, expert consultation, literature study and other methods, including four subsystems （biological resource, soil, vegetation and water environment） and 12 indicators. [ Result] The weights of soil, biological resource, vegetation and water environment were 0.614, 0.219, 0.118 and 0.049, and the top weight of soil showed that farmland improvement had a great influence on soil. Among the 12 indicators, the most important indicators with higher weights were reclamation rate of the land （weight 0.389）, population density （weight 0.164） and the content of soil organic matter （weight 0.088）. Therefore, in EIA of such kind of projects in the future, we should give prominence to the identification, evaluation and monitoring of the main characteristic factor above. [ Conclusion] The research could provide scientific references for the sustainable utilization of resources and estab- lishment of environmental management policies along costal areas of Jiangsu Province.

Integrated benefits of power generation by straw biomass--A case study on the Sheyang Straw Power Plants in Jiangsu Province,China

Power generation using straw biomass has quantifiable benefits from an economic,ecological,and sociological perspective in China.The methods used to construct the assessment models of these integrated benefits were the revenue capitalization approach and the discounted-cash-flow approach.The results indicated that a straw power plant with the capacity of 2.50×10^(7)W and burning 1.23×10^(5)tons of cotton straw could annually supply 1.40×10^(8)kWh of power.However,it would not be until six years later that these results could be measured.Over the long term,the gross benefits could reach up to 4.63×10^(8)Yuan.Therefore,the total benefits are expected to be 1.18×10^(12)Yuan if all available straw resources are used to generate power.The policy implication showed that the long-term integrated benefits of power generation by straw biomass outweighed the short-term benefits.This is the main incentive to use straw biomass for power generation in the future.