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【目的】以武鸣灵水岩溶泉为例,对调查研究灵水来源及环境地质问题所做的一系列工作进行总结,为其他地区的地下水开发利用和保护提供经验和参考。【方法】综合前期的地面调查、钻探、物探、水化学、水文监测以及示踪试验等多种技术手段,总结灵水岩溶泉的形成及水环境退化的原因和趋势。【结果】确定灵水的补给范围;灵水含水层以网状裂隙排泄为主,呈现集中径流带的特征;枯季灵水的水资源量明显减少;水文功能的弱化导致水生生态系统急剧退化。另外,灵水还面临有害微生物快速繁殖、地下水动力减弱引发河流倒灌更加频繁等亟待解决的问题。【结论】灵水研究的一系列工作既展示了成果,也成为岩溶水源地研究的典范。广西其他岩溶地下水的研究还停留在水质水量的调查评价阶段。建议以灵水为参考,从单纯的无机环境向有机生命环境过渡,以应对变化环境下岩溶地下水资源管理和保护所面临的挑战。 相似文献
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YAN Wenwu YANG Limin WANG Qiuquan 《科学通报(英文版)》2005,50(16):1714-1720
The effects of lanthanum at different concentrations on the related photosynthetic activities of Hill reaction, Mg^2+-ATPase and Ca^2+-ATPase in spinach chloroplast were studied. Experimental results showed that lanthanum can increase all the activities at suitable concentration (15-30 mg· L^-1), however, it behaves toxically on them when over used (60 mg. L^-1). To get an improved understanding of the mechanism of lanthanum effects on the photosynthesis of spinach, the different subcomponents in the chloroplast of the cultured spinach were isolated, and the content of lanthanum in each subcomponent was determined by ICP-MS. The results obtained indicated that among these different subcomponents, about 90% out of the total chloroplast lanthanum was located in photosystem Ⅱ (PS Ⅱ) while there was little lanthanum in photosystem Ⅰ (PS Ⅰ). Moreover, size exclusion high performance liquid chromatography (SE-HPLC) coupled with online UV and ICP-MS detections was novelly used for locating lanthanum binding sites in PS Ⅱ proteins for the first time. It was found that lanthanum has two binding sites in PS Ⅱ: La associates with chlorophyll together with magnesium in PS Ⅱ by partly replacing magnesium and also shares the common binding sites of PS Ⅱ proteins together with the inorganic cofactors of calcium and manganese, influencing the process of photosynthesis. 相似文献
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LIU Jie CUI Baoshan DONG Shikui ZHU Jianjun YAO Weike 《科学通报(英文版)》2006,51(B11):59-68
A case study was conducted on Dabao (from Dali city to Baoshan city) and Sixiao (from Simao city to Xiaomengyang town) highways in Longitudinal Range-Gorge Region to investigate the effect of highway construction on photosynthetic rate of roadsides plants. The dominant species in the plant communities were selected to measure the variation of their photosynthetic rate with the distance to the highway, so as to analyze the effect of highway construction on photosynthesis and growth of roadside plants by using mathematic methods including contrast analysis, regress analysis and so on. Results indicate: (1) Highway construction reduced the plant photosynthetic rate of the arbor and crop, and improved the plant photosynthetic rate of the shrub and herbage; (2) highway construction directly affected the plant photosynthetic rate through changing the structure of plant community and living state of plant, and indirectly affected the plant photosynthetic rate through changing its environmental factors; (3) the location and topography of road are also important factors affecting plant photosynthetic rate on roadsides, the influencing incidence and intensity on plant photosynthetic rate under different topographies caused by the two selected highways were obviously different. 相似文献
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笔者主要结合自己多年的工作经验,探讨了植物中的三大作用:光合作用、呼吸作用和蒸腾作用的定义和作用,并详细分析了植物中的三大作用在在园林绿化栽培中的技术应用,一共藏考。 相似文献