摘要
针对近年来普遍存在的城市雨洪灾害问题,利用重庆市沙坪坝气象站1892—2010年的逐月降水量资料,采用线性倾向估计和方差分析法(ANOVA)分析了119 a来重庆主城不同统计时段的降水量及不同等级的降水频率,探讨了近百年来重庆市主城区域降水变化的趋势,以期为城市雨洪灾害防治及城市排水规划的决策提供科学指导。结果表明:119 a来,全年及汛期降水量稍有增加的趋势,年降水量增长向汛期趋于集中;此外,近30 a来,主城区域降水量年际变化幅度有明显的扩大趋势,较大等级降水的发生频率也明显增加;特别是最近10 a,该变幅更加剧烈,连续时段内灾害性气候的发生频率有增长趋势,加剧了城市汛期排水系统的压力。
Algal bloom in the tributaries has become a severe water quality problem in the Three Gorges Reservoir. It is significant of identifying the mechanism of algal bloom to protect the eco-environment. In this study, the author summarized the research progress, analyzed the mechanism of algal bloom and factors affecting the bloom, and gave some control methods. The results indicated that （ 1 ） the bidirectional density current was the most prominent chan- ges caused by the Three Gorges Dam; （2） main factors affecting the algal bloom could be considered to be the nu- trients supply mode and the water stable stratification both caused by the density current. In view of this, the only method to eradicate the bloom was advised to be pollution control over the whole upstream of Yangtze River basin. Moreover, reservoir operation to change the density current＇ s characteristics was also considered to be feasible to control the algal bloom. Further researches and demonstrations in this respect are required.
出处
《长江科学院院报》
CSCD
北大核心
2012年第10期33-36,56,共5页
Journal of Changjiang River Scientific Research Institute
基金
国家科技重大专项“水体污染控制与治理”(2009ZX07315-006)
关键词
重庆
降水量
汛期
灾害性气候
雨洪灾害
water bloom mechanism
density current
control measure
research progress
Three Gorges Reservoir
