丰水期乌江上游干流水库-河流体系硫同位素组成

2007年7月对乌江上游河流、乌江干流上的3座不同库龄的梯级水库（洪家渡水库、东风水库、乌江渡水库）表层及垂直剖面水体的可溶性硫酸盐的硫同位素组成进行了研究。在垂直剖面上，洪家渡水库硫同位素值（δ34S）介于+03‰~+31‰，下泄水为-07‰；东风水库δ34S值介于-75‰~-55‰，下泄水为-68‰；乌江渡水库δ34S值介于-43‰~-06‰，下泄水为-29‰。上述结论表明，硫同位素组成变化反映了水库硫的不同来源及生物地球化学过程。不同水库表层和垂直剖面水体的硫同位素平均值有差别，水库表层的硫同位素比值主要受输入水体的控制，垂直剖面由表层向下硫同位素比值偏负，主要是由于生物作用以及有机硫的氧化造成的。

ON DIVIDING AND EVALUATING THE DEVELOPMENT STAGES OF URBAN AGGLOMERATIONS

Knowing the development stage of urban agglomerations is a precondition for studying or planning and constructing it. Taking into consideration that the fact the standard of dividing the development stage of urban agglomerations isn't unified for the academy, and by drawing lessons from the domestic and international methods of dividing development stages of urban agglomerations and imitating the regulation of life growing up, the development stages of urban agglomerations are divided into four stages, those are the rudiment development stage, the speediness development stage, the tend towards maturity stage and the maturity development stage. The features of the different development stages of urban agglomerations are also generalized. Based on the features of the different development stages of urban agglomerations, the index system and the standard of dividing the development stages of urban agglomerations are designed. Finally, Chang zhu tan urban agglomeration and Pan Chang zhu tan urban agglomeration as cases are evaluated by the methods of fuzzy comprehensive evaluation and analysis of hierarchy procedure. The result of evaluation shows that Chang zhu tan urban agglomeration has entered the speediness development stage, but Pan Chang zhu tan urban agglomeration is still in the rudiment development stage.