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971.
长江(江苏段)沿江开发环境风险监控预警系统 总被引:1,自引:0,他引:1
简要介绍了长江(江苏段)沿江开发带的基本情况,从区域环境质量及社会经济发展趋势两方面阐述了建立长江流域(江苏段)环境风险监控预警系统的意义。在总结目前国内外环境风险决策支持系统发展现状的基础上,论述了系统的目标、总体功能设计、框架设计以及关键技术,探索将地理信息技术运用于区域环境风险管理决策过程的方法,最后提出该系统还需从以下5个方面进行完善和改进,即追溯最大可信度风险源方法,应急救援系统、区域多环境风险事件的复合作用,发展特定有毒有机物水质预测模型和建立优先控制有毒有机物预警系统。该系统将为江苏长江开发战略提供实用型的环境管理手段。 相似文献
972.
沿江开发成就卓著 环境保护任重道远——热烈祝贺《长江流域资源与环境》创刊二十周年 总被引:1,自引:0,他引:1
《长江流域资源与环境》创刊二十年来,刊物随着长江大开发的脉搏而跳动,科学地刻画了“长江战略”的实施历程,履行了为开发和保护长江鸣锣开道的“先声”使命。二十世纪九十年代初,“长江产业带建设的综合研究”课题组论证了长江沿江产业带的建设目标和途径。经过二十多年的建设,长江沿江已经建成为世界规模最大的内河产业带,国际重要的制造业基地,成为国家经济建设的发动机和改革开放的前沿阵地。同时,长江流域正面临着复杂、艰巨的资源环境问题,生态环境保护和建设任重道远。长江流域从可持续发展角度看,有无数需要研究和探索的重大课题,《长江流域资源与环境》作为综合性的学术刊物具有旺盛的生命力 相似文献
973.
974.
依托北槽、建设长江口亚三角洲体系——关于长江流域开发龙头新基地的战略构想 总被引:1,自引:0,他引:1
当前正处于向长江口发展的最好时机。随着长江口深水航道整治工程的开展,长江口水流复杂、河势易变的局面正在改变,加之长江口越江通道的建成通车,在长江口外形成超深水泊位及超深水航道的条件已渐趋成熟。利用长江口外-15 m以深的天然水深建设海上人工岛,就可达到-20 m以深的航道水深,打造河口深水大港,使之成为长江流域水水中转、海陆联运的桥头堡;而整治、疏浚工程所产生的大量泥沙,又为促使横沙东滩及其邻近沙洲加快成陆创造了条件。通过疏浚、促淤、造陆的三位一体,预计可在未来20 a间长江口南港与北港之间、北槽主航道两侧形成500多km2的河口岛群,发育塑造成为长江河口的亚三角洲体系. 相似文献
975.
This study analyses the relation of forest cover and stream flow on the 266 km2 Koga watershed in a headwater of Blue Nile Basin using both observed hydrological data and community perception. The watershed
declined from 16% forest cover in 1957 to 1% by 1986. The hydrological record did not reveal changes in the flow regime between
1960 and 2002 despite the reduction in forest area. This agrees with the perception of the downstream community living near
the gauging station. The upstream community, however, reported both decreases in low flows and increases in high flows shortly
after the forest cover was reduced. The upstream deforestation effect appeared to have been buffered by a wetland lower in
the watershed. This study concludes that community perception can be a complement to observational data for better understanding
how forest cover influences the flow regime. 相似文献
976.
为全面了解并跟踪上海市杨浦区黄浦江流域的水质情况,于2016年1月—2021年12月对杨浦区黄浦江流域的6个监测断面的地表水质量进行调查。采用单因子污染指数分析法和水质综合污染指数分析法,探究了杨浦区内黄浦江流域水质的污染变化特征。结果表明,自2017年杨浦区开展河道整治以来,流域总体水质明显改善,出口水质从重度污染提升到良好水平;居民区密集的虬江断面水质相对较差,后续需加强对虬江流域的污染排放管理;水质污染特征分析结果发现河道的主要污染物种类从氨氮(NH3-N)转换为总磷(TP),说明河道整治提升了河道的自净能力,水质改善效果显著;水质在非汛期优于汛期,气温、降雨、泵站放江和污水排放是影响水质的主要原因。 相似文献
977.
Introduction O rganochlorine pesticides (O C Ps) is a com m on nam e of a group of pesticides consisting of benzene and chlorine. Som e of O C Ps belong to persistent organic pollutants (PO Ps) that are sem i-volatile, bioaccum ulative, persistent and toxic (V allack et al., 1998; Jones and de V oogt, 1999). O CPs are ubiquitous pollutants due to their long-range transport potential. These chem icals have even been found in rem ote areas like the A rctic (M acdonald etal., 2000; A M A … 相似文献
978.
The transboundary Georgia Basin Puget Sound ecosystem is situated in the southwest corner of British Columbia and northwest comer of Washington State. While bountiful and beautiful, this international region is facing significant threats to its marine and freshwater resources, air quality, habitats and species. These environmental challenges are compounded by rapid population growth and attendant uiban sprawl. As ecosystem stresses amplified and partnerships formed around possible solutions, it became increasingly clear that the shared sustainability challenges in the Georgia Basin and Puget Sound required shared solutions. Federal, state and provincial institutional arrangements were made between jurisdictions, which formalized small scale interest in transboundary management of this ecosystem. Formal agreements, however, can only do so much to further management of an ecosystem that spans international boarders. A transboundary regional research meeting, the 2003 GB/PS Research Conference, opened the doors for large-scale informal cross-boarder cooperation and management. In addition to cooperation, continued efforts to stem toxic pollution, contain urban growth, and protect and restore ecosystems, require a commitment from scientists, educators and policy makers to better integrate research and science with decision-making.Former Director of Planning and of Special Projects in the British Columbia Ministry of Municipal Affairs. 相似文献
979.
980.
Yuqin Gao Yunping Liu Li Gao Ming Wu Jhandre Ronald Intriago Gordillo Zheng Xue Shuning Chen 《Journal of the American Water Resources Association》2023,59(4):701-725
Polder is usually used for flood control in the river delta area. With the rapid development of urbanization, the dikes or pumps cut the original stream network system, and the stream network connectivity (SNC) and the river system pattern have changed. The dikes or pumps generally force up the river's water level, and regional flood formation mechanisms and processes have changed. In order to quantitatively describe the characteristics of polder-type flood control measure (PFCM) and the change law of SNC, firstly, the streams inside polders were generalized as virtual streams, a hydrological-hydrodynamic model was constructed by connecting Hydrologic Engineering Center-Hydrologic Modeling System and MIKE11 model. Secondly, an SNC evaluation model was constructed based on flow resistance and hydrological process. Finally, the SNC under different scenarios was simulated and evaluated to reveal the influence of the PFCM on SNC. And the dominance analysis method obtained the main control factors of SNC changes. The results showed that the pumps as the main drainage facility under the PFCM, SNC after the opening of the pumps were increased by 0.060, 0.103, and 0.311 for 50%, 30%, and 3% frequency flood scales compared with the pumps closed, respectively. However, compared with the natural stream (without the PFCM), the SNC decreased by 0.391, 0.456, and 0.487, respectively, at the same time of the same flood scale. The PFCM negatively impacted the SNC, and the number of pumps was the main control factor of the SNC. 相似文献