龙川江水资源对气候变化的敏感性和适应性分析

龙川江流域是我国长江中上游地区极为典型的生态脆弱区,易受气候变化的影响,研究该地区的水资源脆弱性以及其应对气候变化的适应性对于该地区的水资源合理利用十分关键。从该地区水资源的时空分布规律、水利基础设施建设、水生态环境形势和应对气候变化能力4个方面,分别研究了龙川江流域水资源的脆弱性问题。并结合流域的实际情况,从水资源综合管理、水利工程设施建设、建立节水型社会、调整产业结构和依靠科技等方面,提出了提高应对气候变化能力的举措,及时为国家应对气候变化和防灾减灾提供科学支撑。     

白盆珠水库流域下垫面变化的洪水响应研究

基于栅格分布式水文模型并结合GIS技术,进行东江流域白盆珠水库子流域下垫面变化的洪水响应分析.根据该流域现状土地利用情景分析方法构建9种流域下垫面情景,选取大、中、小3场典型洪水过程,定量分析下垫面变化造成的洪水响应.结果表明:林地及其空间分布在截留降雨、消减洪峰和延缓洪峰滞时方面效果明显,故保护林地,特别是沿河道及流...     

广西水资源近年来变化趋势及可利用水资源潜力分析

对近10年来广西降水量、水资源总量以及用水情况进行了统计分析,并在此基础上对广西各地级市水资源潜力进行了计算与评价,结果表明：（1）全区水资源量受降雨量的影响较大,近10年来全区降水量、水资源量呈现下降趋势,用水量呈上升趋势;（2）各地级市由于经济发展以及用水结构不同,近5年来用水量变化不一,其中柳州、桂林呈明显的下降趋势,南宁、贵港上升趋势明显;（3）广西可利用水资源潜力比较大,多数行政区等级为较丰富及以上,其中梧州最多,达到10973．81m3／人,钦州、玉林、北海为缺乏和较缺乏地区,其中玉林最少,仅有247．8m3／人;（4）广西地区间可利用水资源潜力存在巨大的差异,在进行经济人口布局规划时应合理考虑。     

淮安市地表水水质变化趋势分析

应用季节性kendall检验法,对2000—2009年淮安市主要水系河流的地表水水质指标变化趋势进行分析评价。结果表明:随着近年来淮河流域水污染防治力度的加大,以及对洪泽湖作为南水北调东线工程输水主干线自身的治理,淮安市境内的主要河流湖泊总体水质略有好转,由于淮河入海水道水功能区划的调整,入海水道总体水质有所下降,而洪泽湖水体TP含量呈逐年上升趋势,其他水体水质总体变化不大。     

Sensitivity of juvenile salmonid growth to future climate trends

Seasonal temperature and bioenergetic models were coupled to explore the impacts on juvenile salmonid growth of possible climate‐induced changes to mean annual water temperature and snowpack in four characteristic ecoregions. Increasing mean temperature increases juvenile growth in streams that currently experience cool spring temperatures. In streams with currently warm spring temperatures, an increase shortens the duration of optimal conditions and truncates growth. A loss of snow enhances growth in cool‐summer streams and decreases growth in warm‐summer streams. The relative impacts of such climate change trends will vary significantly across ecoregions. Copyright © 2010 John Wiley & Sons, Ltd.     

The Sanaga discharge at the Edea Catchment outlet (Cameroon): An example of hydrologic responses of a tropical rain‐fed river system to changes in precipitation and groundwater inputs and to flow regulation

The Sanaga River is one of Sub‐Saharan Africa's largest and greatly regulated rivers. Available flow data for this hydrosystem largely cover the pre‐ and post‐regulation periods. From comparisons between unregulated (hypothetical) and observed scenarios, it has been possible to separate and to quantify hydro‐climatic (groundwater + rainfall) change effects from anthropogenic impacts (especially dam‐related alterations). To appreciate shifts in the river regime, discontinuity detection tests and the IHA model were applied to discharge data series reflecting average and extreme flow conditions, respectively. Results obtained principally from the Hubert segmentation method reveal that a major discontinuity occurred in 1970–1971 separating a surplus phase between 1945–1946 and 1969–1970, and a deficient and much contrasted one, from 1971/1972. This implies that the Sanaga catchment is dominantly affected by hydro‐climatic changes. However, wide land cover/land use changes experienced here since 1988 have resulted in an increase in surface runoff. Additional quickflows linked to these changes may have partly compensated for the substantial decline in the dry season rainfall and groundwater inputs observed from this date. Although at the monthly scale, dam‐related impacts on average flows increase with stage of regulation, the seasonal variability of the river regime remains generally unaffected. A comparison of the IHA statistics, calculated from unregulated and observed streamflow data, show that hydrologic shifts occurring in maximum and minimum discharges are mostly significant from 1971/1972 and are mainly due to the action of dams. Minimum flows appear, however, widely impacted, thus reflecting the prime objective assigned to the existing reservoirs, constructed to supplement flows for hydroelectricity production during the dry season. Copyright © 2010 John Wiley & Sons, Ltd.     

汶川地震对陈村坝基渗流影响分析

汶川地震发生后不久,陈村大坝坝基帷幕后部的浅层扬压力测孔和深部排水测孔水位普遍下降,坝基渗漏量显著增加,表明坝基岩体和帷幕受地震影响微细裂隙张开,渗透性增强.坝基经过丙凝化学加强灌浆的部位,测孔水位下降幅度较小,水位恢复过程较快,显示出丙凝化灌的优异防渗和抗震性能.汶川地震对陈村大坝的稳定以及坝基岩体和帷幕没有产生损坏...     

广东韩江松源河省界界面水质变化及环境管理策略

根据2007、2008年7次调查的实测资料,分析了松源河及多宝水库的水质变化过程,并讨论了影响水质恶化的原因;根据水质变化特点,提出了水质保洁及科学管理的策略,为梅州的绿色崛起、“以人为本”的和谐社会服务.     

分块跟踪中的目标模板更新方法

在基于模式匹配的目标跟踪算法中,由于受遮挡、自身外观变化的影响,模板更新问题一直是目标跟踪的一个难题,因为遮挡和外观变化均表现为目标内灰度的变化,但由障碍物遮挡引起的灰度变化不能更新为模板;而由目标自身引起的灰度变化又要即时地更新为模板。为此,提出一种带有遮挡和外观变化判断的局部模板更新算法。算法使用分块模板并根据目标中变化的信息分别来自目标和背景的概率来区别外观变化和遮挡这两种情况。目标被部分遮挡时,通过不更新模板来防止障碍物信息混入模板;目标外观变化时,提出一种新的局部模板更新算法以适应目标的不断变化。实验结果表明,该算法既能较好地适应目标的外观变化,又具有较强的抗遮挡能力,比整体模板更新算法具有更好的鲁棒性。