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Coal fire burning around the world is an environmental catastrophe characterized by the emission of noxious gases, particulate matter, and condensation by-products. In this study, coal fire temperature is retrieved based on Landsat 5 TM images and Generalized Single-Channel Algorithm (GSCA), in Wuda coalfield, Inner Mongolia, China. Then coal fire zones are extracted by Jenks' natural breaks and threshold methods based on temperature images. Changes of coal fire zones are analyzed from 1989 to 2008. The results are summarized as follows: 1) The coal fire temperature retrieval method based on Landsat 5 TM and the GSCA model is effective and feasible, because the temperature error is relatively small (from −2.9°C to +2.6°C) between the measured temperature and the retrieved temperature. 2) The accuracy is relatively high to extract coal fire zones through the Jenks' natural breaks and threshold methods, because 83.56% of surveyed area is located in the coal fire zones extracted in 2005. 3) The coal fire area increased 9.81 × 10 m from 1989 to 2005, and the annual growth is about 6.1 × 10 m, with an annual increasing rate of 2.48%. The area of coal fire decreased by 8.1 × 10 m from 2005 to 2008. [ABSTRACT FROM AUTHOR]

Formulation of different ecological zone plans according to the corresponding protection targets and the necessity of proper conservation policy is one of the measures to achieve the goal of ecological conservation in China. In order to clarify the interrelation among key ecological zone plans, this paper carried out the research on spatial relation of priority areas of biodiversity conservation and three key ecological areas (key ecological function areas, key regions of ecological service function, national nature reserves) and the research on ecological conditions, based on multi-scale ecological spatial theme information, which incorporates elements like ecological quality and type, and by the aid of spatial information analysis and GIS modeling. The results showed a contrastively fine spatial consistency with 68.8% of priority areas of biodiversity conservation overlapping with three key ecological areas. Although the environment in priority areas of biodiversity conservation were in good conditions, protection pressure is also increasing, powerful supervision and protection should not be ignored. The environmental conditions in the overlapping areas, as a whole, were superior to those in the non-overlapping areas. Since two areas have different characteristics, targeted protection measures should be formulated based on this difference, which will be very important for biodiversity conservation in priority areas of biodiversity conservation. [ABSTRACT FROM AUTHOR]

Based on multi-source data, this paper evaluated the economic value of ecological services in the Yeyahu Wetland Nature Reserve, Beijing, China. The ecological services of wetland included gas regulation, water quality improvement, biodiversity maintenance, erosion control, water supply, recreational opportunity, raw material supply and existence value. Multiple conventional evaluation methods were used to calculate the value of eight wetland services. The results showed that significant values came from biodiversity maintenance and recreational opportunity. The main reasons were as follows. Firstly, Yeyahu Wetland Nature Reserve was the habitat for migrant birds, and government had payed more efforts to protect precious birds. Secondly, the population is large in Beijing. People enjoyed going outside and enjoyed the natural and artificial wetland scenes. At the same time, most people were prepared to pay for wetland conservation. The decline of vegetation cover made the economic value of erosion control the lowest. While the shrink of water resource and the deteriorative water quality caused the economic value of water supply lower. The evaluation results could help decision-makers understand the present status of the Yeyahu Wetland Nature Reserve and provide a scientific basis for strategic decision. [ABSTRACT FROM AUTHOR]