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In recent decades, rapid urbanization and climate change have led to the degradation of many coastal wetlands, impairing their ecosystem functions and services. However, few studies have analyzed how these historical degradation trends will continue into the future, especially in rapidly developing regions. Here, we quantified the long‐term wetland degradation from 1984 to 2016 in Hangzhou Bay and then developed land use simulation models to predict the spatial locations of wetland degradation to 2046 under different scenarios. Key findings include the following: (a) there was a statistically significant decreasing trend for the natural wetlands of ~10 km2 yr−1 on average from 1984 to 2016; (b) after the establishment of an economic development zone in 2001, the degradation rate more than quadrupled, accelerating from ~4 to ~18 km2 yr−1; and (c) if the high degradation rate continues (the economic development scenario), then the coastline will move approximately 5.89 km inland, significantly undermining the protections against sea level rise. In contrast, in the wetland protection scenarios, the projected degradation could be mitigated by ~20%. The proposed framework to reveal the key historical drivers of degradation and potential future protection strategies of wetlands provides much needed insights and tools for protection of other coastal wetlands undergoing rapid development.

Coal fires have been found to be a serious problem worldwide in coal mining reserves. Coal fires burn valuable coal reserves and lead to severe environmental degradation of the region. Moreover, coal fires can result in massive surface displacements due to the reduction in volume of the burning coal and can cause thermal effects in the adjacent rock mass particularly cracks and fissures. The Wuda coalfield in Northern China is known for being an exclusive storehouse of prime coking coal as well as for being the site of occurrence of the maximum number of known coal fires among all the coalfields in China and worldwide, and is chosen as our study area. In this study, we have investigated the capabilities and limitations of ALOS PALSAR data for monitoring the land subsidence that accompanies coal fires by means of satellite differential interferometric synthetic aperture radar (DInSAR) observations. An approach to map the large and highly non-linear subsidence based on a small number of SAR images was applied to the Wuda coalfield to reveal the spatial and temporal signals of land subsidence in areas affected by coal fires. The DInSAR results agree well with coal fire data obtained from field investigations and thermal anomaly information, which demonstrates that the capability of ALOS PALSAR data and the proposed approach have remarkable potential to detect this land subsidence of interest. In OPEN ACCESSRemote Sens. 2013, 5 1153 addition, our results also provide a spatial extent and temporal evolution of the land subsidence behavior accompanying the coal fires, which indicated that several coal fire zones suffer accelerated ongoing land subsidence, whilst other coal fire zones are newly subsiding areas arising from coal fires in the period of development.

Two types of pisha-sandstones of purple sandstones and gray sandstones, widely distributing in the wind-water erosion crisscross region of China, were selected and used in laboratory experiments for a better understanding of the drying-wetting-freezing weathering process resulting from the apportionment of water or salt solution to rock samples. Weathering experiments were carried out under the conditions of environment control (including temperature, moisture and salt solution). All rock samples were frequently subjected to 140 drying-wetting-freezing cycles. The influences of weathering process were evaluated. It was found that the different treatments of moisture and salt solution applications could affect the nature of the weathering products resulting from drying-wetting-freezing. It was also observed that salt solution could effectively alleviate the weathering of pisha-sandstones. Although not all the observations could be explained, it was apparent that simulated environmental factors had both direct and indirect effects on the weathering of rocks.

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