[1] Results of clay mineralogy, major element geochemistry, and Sr and Nd isotopes in 93 argillaceous samples collected from drainage basins of the Pearl, Red, and Mekong rivers reveal different degrees of chemical weathering in Southeast Asia despite similar climate conditions across these regions. The kaolinite/illite ratio, illite chemistry index, and illite crystallinity can be used as indicators of chemical weathering intensity. These mineralogical proxies combined with the K 2 O/(Na 2 O + CaO) molar ratio, chemical index of alteration (CIA), and weathering trends observed from major element results indicate intensive silicate weathering in the Pearl River basin, moderate to intensive in the Mekong River basin, and moderate in the Red River basin. Although a significant modification of eNd (0) Sr ratios are controlled by various states of chemical weathering of high-Sr minerals such as plagioclase (rich in Na and Ca) with a linear decrease trend from the Pearl, Mekong, to Red river basins. Our results suggest that it is not the warm climate with heavy monsoon precipitation but tectonics playing the most significant role in controlling weathering and erosion processes in south China and Indochina Peninsula. Strong physical erosion caused by tectonic activities and river incision along the eastern margin of the Tibetan Plateau and along the Red River fault system is responsible for high contents of primary minerals in the lowlands of Red and Mekong river basins.

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Given the fact that more and more governments invest heavily in e-government design and implementation, e-government has become an evolving and important research area in the IS field. Most, if not all, currently published e-government strategies are based on successful experiences from developed countries, which may not be directly applicable to developing countries. Based on a literature review, this study summarizes differences between developed/developing countries. It identifies key factors for a successful e-government implementation and proposes an implementation framework. As a demonstration, we follow the guidance of the proposed framework in conducting a case study to analyze the implementation strategies of e-government in developed and developing countries.

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Long-term records show high over the drainage basins is still not clear, concentrations of dissolved major elements in the especially for the rivers draining in areas with Changjiang (Yangtze River) and the Huanghe (Yellow River}. The Huanghe drainage basin is characterized by intense weathering and erosion of carbonates and evaporites, while weathering and erosion of carbonates and silicates over the drainage basin is the main source of major elements in the Changjiang. The rock/soil complex rock/soil compositions and/or different climate zones. The Changjiang (Yangtze River} and Huanghe (Yellow River} represent a drainage basin area of 1.8x106 km z and 0.75x106 km z, respectively (Figure 1}. After the Amazon, Zaire, and Orinoco, the Changjiang is the fourth largest source of fresh composition and tectonics of the drainage basin water to the ocean [Milliman and Meade, 1983; are more important than atmospheric precipitation Milliman et al., 1985]. Annual water and sediment in affecting major element composition of these discharges of the Changjiang average 928.2x109 m 3 two rivers. Compared with other large rivers of and 0.Sx10 lz kg, respectively. The averaged the world, the high suspended sediment and major monthly water discharge of the Changjiang ranges element loads of the Changjiang and Huanghe from 10.0x103 m•/s to 49.0x10 • m3/s at the Datong reveal intense physical and chemical erosion over Hydrographic Station (625 km inland from the the Chinese continent. river mouth), corresponding to a variation of suspended sediment concentration from 0.1 g/L to 1. Introduction 0.8 g/L in the river. Much higher water discharge values (60-70x10 • m•/s) are observed during the The elemental geochemistry in some of the flood period. The Huanghe, long known for its large Chinese river/estuary systems and the high suspended sediment concentration, transports coastal areas has been extensively studied in 43.2x109 m 3 of fresh water and 1.1x10 lz kg of recent years [Hu et al., 1982; Thomas and Martin, suspended sediment annually to the river mouth. 1982; Li et al., 1984; Milliman et al., 1984; The monthly mean water discharge ranges from Edmond et al., 1985; Elbaz-Poulichet et al., 0.5x10 • m3/s to 2.7x103 m3/s at the Lijin 1987; Zhang, et al., 1988], mainly owing to Hydrographic Station (150 km inland from the international cooperation and/or joint study river's mouth), but the water discharge may programs. This compensates partly for the lack of exceed 10.0x103 m3/s in flood periods. The elemental composition data of Chinese river/ocean suspended sediment concentration in the lower systems in the international literature. However, reaches of the Huanghe ranges from 2.8 g/L in most of the studies are restricted to behavior of lower water stage to 45.6 g/L during high water chemical elements in the estuarine and coastal stage, with a mean value of 25.6 g/L. Values of environments and especially to that of trace and 200-250 g/L have been observed during the flood nutrient elements; little attention is paid to periods; it is...

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