东湖通道工程沙滩浴场围堰施工对水中胞外碱性磷酸酶动力学行为的影响

城镇化过程常伴随市政建设面积与强度的大幅度增加，但其与湖泊富营养化的关系尚未得到充分的研究。2014年3-5月在武汉东湖通道工程沙滩浴场围堰施工区与相关湖区（郭郑湖、汤菱湖、团湖）的19个位点分5次采集水样，分析了水中胞外碱性磷酸酶的动力学参数及其与溶解有机磷和溶解反应性磷比值的关系。结果表明，施工致使酶的最大反应速度与底物亲和力均显著降低，有机磷酶促再生为生物可利用性无机磷的周转时间明显延长。这一结果指示施工区磷营养的相对充足，施工干扰可能有效促进了沉积物磷向水柱的补给。

Effects of cofferdam construction in bathing beach of underwater tunnel engineering on kinetics of extracellular alkaline phosphatase in water of Donghu Lake,China

Urbanization invariably leads to substantial increases in urban areas and a tendency to increase municipal construction. However, the effects of urbanization on lake eutrophication are not studied adequately. The collection of water samples was repeated 5 times at 19 sites in the construction area of a cofferdam at a bathing beach, with underwater tunnel engineering, and in the relevant basins of Donghu Lake in Wuhan City, such as Guozheng Lake, Tangling Lake, and Tuanhu Lake. The collection of samples was conducted from March to May 2014. The kinetic parameters of extracellular alkaline phosphatase and their relations with the ratios of the dissolved organic phosphorus to the soluble reactive phosphorus were determined in the lake water. It was found that the construction led to significant decreases in the maximum reaction velocity and the affinity of the studied enzyme for the substrate. Furthermore, the construction activities caused a significant increase in the turnover time for organic phosphorus regenerating to bioavailable phosphate, mediated by the enzymatic mechanism. This finding implies that phosphorus was relatively replete in the water of the construction area. The disturbance caused by the construction could significantly enhance the phosphorus supply from the sediment to the water column.