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浙北低山丘陵区天然次生林和人工毛竹林降雨化学特征比较 被引量:2
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作者 李谦 王小明 周本智 《生态与农村环境学报》 CAS CSCD 北大核心 2014年第3期324-330,共7页
森林降水化学特征定量研究对于准确估算森林生态系统养分循环的养分元素浓度有重要意义。以中亚热带人工毛竹林和天然次生林为研究对象,分析2种森林类型的穿透雨、地表径流和流域出口径流各离子浓度时空动态变化特征。结果表明,与人... 森林降水化学特征定量研究对于准确估算森林生态系统养分循环的养分元素浓度有重要意义。以中亚热带人工毛竹林和天然次生林为研究对象,分析2种森林类型的穿透雨、地表径流和流域出口径流各离子浓度时空动态变化特征。结果表明,与人工毛竹林相比,天然次生林具有较高的林冠截留作用和枯落物截持水能力,产生的林内穿透雨和地表径流较少;大气降雨中各离子浓度差异较大,由高到低依次为SO42-、 NO3-、Na+ 、Cl- 、K+ 、Ca2+、NH4+ 和Mg2+;人工毛竹林和天然次生林林内穿透雨的Na+淋溶系数分别为0.49和0.85,而其他离子都有不同程度增加,表现为正淋溶;与大气降雨相比,2种林分的地表径流中各离子都表现为正淋溶,淋溶系数在1.127~10.16之间,以K+和NO3-较大,而Na+和NH4+ 较小;流域出口径流中K+和NH4+相对于大气降雨有一定下降,迁移系数分别为0.90和0.21,而Ca2+和Mg2+浓度则明显增加,迁移系数分别为7.55和22.78;2种林分不同层次的降水化学特征差异主要表现在离子浓度上,除Na+和Mg2+外,天然次生林各层次的离子浓度均大于人工毛竹林。 展开更多
关键词 穿透雨 地表径流 流域出口径流 降雨化学特征 森林
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Wet-Dry Runoff Correlation in Western Route of South-to-North Water Diversion Project,China 被引量:2
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作者 HUANG Xiao-rong ZHAO Jing-wei YANG Peng-peng 《Journal of Mountain Science》 SCIE CSCD 2015年第3期592-603,共12页
The Western Route of the South-to-North Water Diversion Project is an important trans-basin diversion project to transfer water from the upstream Yangtze River and its tributaries (water-exporting area), to the upst... The Western Route of the South-to-North Water Diversion Project is an important trans-basin diversion project to transfer water from the upstream Yangtze River and its tributaries (water-exporting area), to the upstream of the Yellow River (water- importing area). The long-term hydrologieal data from 14 stream gauging stations in the Western Route area and techniques including the pre-whitening approach, non-parametric test, Bayes, law, variance analysis extrapolation, and Wavelet Analysis are applied to identify the streamflow eharacteristics and trends, streamflow time series cross-correlations, wetness-dryness encountering probability, and periodicities that occurred over the last 50 years. The results show that the water-exporting area, water- importing area, and the streteh downstream of the water-exporting have synehronization in high-low flow relationship, whereas they display non- synchronization in long-term evolution. This corresponds to the complicated and variable climate of the plateau region. There is no obvious increasing or decreasing trend in runoff at any gauging station. The best hydrological eompensation probability for rivers where water is diverted is about 25% to lO%, and those rivers influenced significantly by diversion are the Jinsha and Yalong rivers. Proper planning and design of compensation reservoirs for the water-exporting area and stretch downstream of the water- exporting area can increase the hydrological compensation possibility from water-exporting area to the water-importing area, and reduce the impact on the stretch of river downstream of the water- exporting area. 展开更多
关键词 South-to-North Water Diversion Project Yangtze River Streamflow Encounter probability Correlation coefficient Cycle Hydrologicalcompensation
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