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991.
孔繁德 《中国环境管理干部学院学报》2012,(6):31-33
按照国家统计局标准,秦皇岛市城市规模已达到大城市标准,应充分发挥辐射带动作用,加快城镇化步伐;抓住城市发展综合效益最佳期的机遇,促进可持续发展;坚持产业结构多元化,各产业协调发展。秦皇岛市生产总值在河北省属中上水平,在沿海开放城市中属落后水平,应尽快提高生产总值;秦皇岛市在科学发展中属比较先进水平,在民生发展方面属先进水平,其中生态方面优势明显,应进一步发挥生态优势,保护环境。秦皇岛市科技创新取得显著成绩,但任务艰巨,必须进一步实施创新驱动发展战略。 相似文献
992.
Peter E. Black 《Journal of the American Water Resources Association》2012,48(2):244-255
Black, Peter E., 2012. The U.S. Flood Control Program at 75: Environmental Issues. Journal of the American Water Resources Association (JAWRA) 48(2): 244‐255. DOI: 10.1111/j.1752‐1688.2011.00609.x Abstract: Recent, recurring, and increased magnitude floods adversely challenge long‐held and erroneous concepts of flood control. This article focuses on the environmental issues with comprehensively reviewed essentials of the United States (U.S.) riverine Flood Control Program, including news reports, scientific articles, books, and landmark treatises. For the past three‐quarters of a century, U.S. floods have continued (and will continue) to occur, causing increasing property damage with growing fiscal loss. Reasons include inattention to fundamental principles of physics, hydrology, and ecology. There are also important challenges involving environmental policy, economics, and common sense. Measures afforded by the existing program encourage and enable investment in floodplains while violating a variety of natural principles that make the situation worse. This detailed review includes the questionable (actually untrue) justification in the document‐setting policy for the 1936 Omnibus Flood Control Act. The well‐documented evidence is overwhelming. An alternative approach is presented that would enable and celebrate natural floods, managing their ecological and hydrological values, and not attempting to control them. 相似文献
993.
采用生物填料、阿科蔓生态基和生态浮盆等材料构建低动力复合净水系统(LCWPS)进行生态农庄人工景观池水质净化技术示范研究。系统稳定运行后的周年监测结果表明,整体系统使人工景观池的CODMn、TN、NH4+-N、TP和浊度分别下降61.1%~62.8%、36.0%~39.9%、14.3%~35.7%、66.7%~79.5%和76.8%~79.8%,水质溶解氧浓度(DO)上升72.7%~126.0%,景观池水质达到《地表水环境质量标准》(GB3838-2002)中景观水域需要的V类水质标准,并能长期保持稳定。从管理维护成本角度考虑,利用LCWPS净化生态农庄人工景观池水质能达到节能节水的目的。 相似文献
994.
在我国经济迅速发展的同时,资源环境消耗不断加剧,生态问题日益突出,生态补偿成为改善环境的重要途径。在总结国内外重要文献的基础上,提出了生态补偿的背景、内涵和类型,并借鉴国内外生态补偿的实践,梳理了生态补偿原则、主体、途径、标准等生态补偿机制问题。 相似文献
995.
现代生态补偿研究综述 总被引:1,自引:0,他引:1
在我国经济迅速发展的同时,资源环境消耗不断加剧,生态问题日益突出,生态补偿成为改善环境的重要途径。在总结国内外重要文献的基础上,提出了生态补偿的背景、内涵和类型,并借鉴国内外生态补偿的实践,梳理了生态补偿原则、主体、途径、标准等生态补偿机制问题。 相似文献
996.
Kris W. Knight Richard C. Schultz Cathy M. Mabry Thomas M. Isenhart 《Journal of the American Water Resources Association》2010,46(2):311-322
Knight, Kris W., Richard C. Schultz, Cathy M. Mabry, and Thomas M. Isenhart, 2010. Ability of Remnant Riparian Forests, With and Without Grass Filters, to Buffer Concentrated Surface Runoff. Journal of the American Water Resources Association (JAWRA) 46(2):311-322. DOI: 10.1111/j.1752-1688.2010.00422.x Abstract: Riparian forest buffers established according to accepted conservation practice standards have been recommended as one of the most effective tools for mitigating nonpoint source pollution. The midwestern United States is characterized by many kilometers of narrow, naturally occurring forests along streams. However, little is known about the relative effectiveness of these remnant forests compared with these newly established buffers. This study compared the ability of naturally occurring remnant forests with and without adjacent planted grass filters to buffer concentrated flow paths (CFPs) originating in crop fields along first- and second-order streams in three northeast Missouri watersheds. Remnant forests breached by runoff through CFPs were narrower than those that dispersed 100% of the CFPs. Remnant forests with adjacent grass buffers were nearly twice the width as those without grass filters. We also found that CFPs, which developed within remnant forests and at the base of in-field grass waterways, were potential sources of sediments to streams. Methods to mitigate these CFPs warrant further investigation. Our study suggests that although these natural remnant forests provide substantial buffering capacity, both improved management and/or the addition of an adjacent grass filter would improve water quality by reducing sediment loss to streams. Inferences can be used to inform the design and management of similar conservation buffer systems within the region. 相似文献
997.
地貌环境与城市化相互关系是城市自然地理学研究的核心,从城市地貌学角度分析了上海城市地貌特点和地貌形变过程,探讨了城市地貌形变与城市生态环境之间的关系,特别是城市地貌形变引起的一系列生态环境效应,如城市防汛压力增大、地面积水愈加严重、城市河流淤积加厚、城市植被生境趋于单一等。在此基础上提出了三大应对策略:(1)在黄浦江下游河口尽早修建挡潮闸;(2)沿黄浦江、苏州河修建生态防汛墙;(3)及时进行城市规划调整,在再城市化过程中合理规划城市水面率和城市蓝线宽度,依据地貌形变的强弱来增加负地形(河流、湖泊)的比例,使已经损失的地面标高得到一定的补偿。上海只有充分重视城市地貌特点才能走上安全、健康、持续的城市发展道路。 相似文献
998.
长江三峡工程生态与环境监测系统是针对三峡工程可能引起的生态环境问题而建立的跨地区、跨部门、多学科、综合性和研究性的监测网络,自1996年建立以来,监测系统按照规定的监测指标体系和操作规范,对三峡生态环境进行全过程跟踪监测,取得了大量生态与环境数据及资料,为三峡生态与环境的监测与保护发挥了重要作用,为我国大型江河湖泊的综合性生态环境监测工作做出了积极探索和有益尝试。随着水库逐步转入正式运行期,三峡监测系统的监测重点也由为工程建设服务转向为工程运行服务阶段。通过对三峡工程监测系统发展至现阶段进行总结研究,梳理了三峡工程监测系统的特点、运行成效、示范意义等,最后指出了监测系统今后一个阶段内的发展方向 相似文献
999.
Between 1950 and 1963 approximately 11 million kilograms of mercury (Hg) were used at the Oak Ridge Y-12 National Security Complex (Y-12 NSC) for lithium isotope separation processes. About 3% of the Hg was lost to the air, soil and rock under facilities, and East Fork Poplar Creek (EFPC) which originates in the plant site. Smaller amounts of Hg were used at other Oak Ridge facilities with similar results. Although the primary Hg discharges from Y-12 NSC stopped in 1963, small amounts of Hg continue to be released into the creek from point sources and diffuse contaminated soil and groundwater sources within Y-12 NSC. Mercury concentration in EFPC has decreased 85% from ∼2000 ng/L in the 1980s. In general, methylmercury concentrations in water and in fish have not declined in response to improvements in water quality and exhibit trends of increasing concentration in some cases. 相似文献
1000.
V. K. Ryabitsev 《Russian Journal of Ecology》2000,31(2):108-112
The demography of the gray plover was studied using color banding at a stationary control plot in the northern Yamal tundra
for seven years. Data on the dynamics of nesting density, fertility, breeding success, and site tenacity are presented. Cases
of polygyny and the absence of nesting are described. Factors affecting population dynamics are discussed. 相似文献