Along with its economic reform, China has experienced a rapid urbanization. This study mapped urban land expansion in China using high-resolution Landsat Thematic Mapper and Enhanced Thematic Mapper data of 1989/1990, 1995/1996 and 1999/2000 and analyzed its expansion modes and the driving forces underlying this process during 1990-2000. Our results show that China's urban land increased by 817 thousand hectares, of which 80.8% occurred during 1990-1995 and 19.2% during 1995-2000. It was also found that China's urban expansion had high spatial and temporal differences, such as four expansion modes, concentric, leapfrog, linear and multi-nuclei, and their combinations coexisted and expanded urban land area in the second 5 y was much less than that of the first 5 y. Case studies of the 13 mega cities showed that urban expansion had been largely driven by demographic change, economic growth, and changes in land use policies and regulations.

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It has been widely accepted that there is a close relationship between the land use type and water quality. There have been some researches on this relationship from the perspective of the spatial configuration of land use in recent years. This study aims to analyze the influence of various land use types on the water quality within the Chaohu Lake Basin based on the water quality monitoring data and RS data from 2000 to 2008, with the small watershed as the basic unit of analysis. The results indicated that there was significant negative correlation between forest land and grassland and the water pollution, and the built-up area had negative impacts on the water quality, while the influence of the cultivated land on the water quality was very complex. Besides, the impacts of the landscape diversity on the indicators of water quality within the watershed were also analyzed, the result of which indicated there was a significant negative relationship between them. The results can provide important scientific reference for the local land use optimization and water pollution control and guidance for the formulation of policies to coordinate the exploitation and protection of the water resource.

[1] To characterize atmospheric dissolvable iron over the Southern Ocean (SO) and coastal East Antarctica (CEA), bulk and size-segregated (0.056-18 μm in diameter) aerosols were collected from 34°S, 109°E to 69°S, 76°E and between 69°S, 76°E and 66°S, 110°E ) over CEA; the total dissolvable Fe followed the same trend. Over the SO, a single-peak size distribution of Fe(II) existed. Over CEA, a bimodal size distribution of Fe(II) appeared, with the first peak at 0.32-0.56 μm and the second peak at 5.6-10 μm. Higher Fe concentrations over CEA than over the SO and the existence of coarse mode Fe(II) over CEA suggest potential dust sources in Antarctica. The fractional Fe(II) solubility ranged from 0.58% to 6.5% and decreased with total Fe concentration increase. The estimated atmospheric fluxes of Fe (II)