Morphodynamic responses of nourished beaches in SW Spain

Coastal erosion in SW Spain is affecting man-made structures and beaches that represent an important economic resource in the area. In the last decade the Spanish government carried out several nourishment works that have limited durability. Most of the artificial beach fills consist of a spill of natural dredged sand on the visible beach, leading to a flat, artificial berm with an important seaward slope and narrow foreshore. As a result, the initial dissipative profile was transformed into a fully reflective one. A beach monitoring program was carried out to record morphological evolution after the nourishment works. Several field assessments of disturbance depth were also made to characterize beach morphodynamics of a nourished beach (Rota) and a natural dissipative one (Tres Piedras), whose slope was similar to the pre-nourishment gradient of Rota beach. Natural dissipative beaches were characterized by spilling breakers that did not significantly affect bottom sand. The severe erosion recorded in the nourished zones was related to the new morphodynamic regime acting on these beaches, which was controlled by high erosive plunging breakers associated with high foreshore slopes. In conclusion, other nourishment practices should be used, better adapted to the natural beach morphodynamics of the zone, taking also into account the original grain size and density of the beach sands, in order to obtain more durable artificial beaches.     

三峡工程对长江中游湖泊生态影响及监测因子优选

分析了三峡工程的兴建对长江中游湖泊生态环境的影响,为保护长江中游湖泊生态环境,优选出了８类指标的监测因子,以期通过这些因子的监测,可以较全面,准确地反映了三峡工程对长少中游湖泊生态环境状况的影响及其动态变化趋势,为保持长江中游湖泊生态系统的良性特环境提供科学依据。     

风险管理在隧道及地下工程中的应用研讨

根据隧道和地下工程的特点,明确风险的定义,并对隧道及地下工程建设中决策、实施以及运营各阶段的风险因素进行了系统总结;提出了隧道及地下工程的风险管理方法,包括风险分析、风险评价、风险应对和风险监控4个步骤;分析了隧道和地下工程风险管理实践中存在的问题,主要包括对风险的认识存在误区、风险管理系统过于分散、缺乏统一的风险接受准则和接受等级以及目前的风险管理体系与当前社会环境不相符等;针对上述问题,提出了关于提高风险管理理论水平、建立动态的风险管理体系、加强重大事故预测预报、完善隧道和地下工程风险管理的法律法规以及改变"被动式"的管理理念等方面的建议。     

盘龙江上段截污工程社会效益和生态系统服务价值评估

通过背景资料收集、问卷调查、条件价值评估等方法,对昆明市盘龙江上段截污工程的社会效益进行了评估,估算了环境整治后盘龙江上段的生态系统服务价值。研究结果表明：昆明市盘龙江上段综合整治具有良好的社会效益,体现出较高的生态系统服务价值。     

防洪工程与海河平原水资源短缺

海河平原水资源短缺日益严重,其成因和缓解对策是当前紧迫的研究课题。防洪工程对海河平原水资源影响的研究,有助于从源头上解决水资源短缺。通过分析海河流域旱涝成因和防洪工程体系,探讨了防洪工程体系对平原水资源储备的破坏,指出防洪工程大幅度减少平原水资源的供给,提出基于防洪工程改造和水资源储备恢复的缓解水资源短缺对策。文章提出防洪工程引起海河平原水资源减少和通过恢复、重建湖泊和沼泽等湿地来增加海河平原水资源的新观点,对于全面审视海河流域防洪工程的作用、综合分析海河平原水资源短缺的成因和正确采取缓解水资源短缺的对策具有一定的启迪作用。     

余压过滤系统在工业循环水系统中的应用

砂过滤器是一种传统而高效的水处理设备,广泛应用于钢铁企业循环水系统。目前钢铁企业最常用的砂滤器是高速或中速砂过滤器。本文结合新型浅层砂过滤器的应用,对余压过滤系统技术（余压全滤、余压旁滤）应用于钢铁企业循环水系统进行了分析,并对具体的设计方法进行了详细的介绍,可供实际生产和工程建设参考。     

CORRELATION OF COPROSTANOL TO ORGANIC CONTAMINANTS IN COASTAL AND ESTUARINE SEDIMENTS OF THE U.S.1

ABSTRACT: Results from the National Status and Trends Program, a nationwide effort to evaluate U.S. coastal and estuarine environmental quality, are analyzed to provide information about regional sources of organic contaminants in the benthic environment. Spearman's rank correlation procedure is applied to measurements of coprostanol, a chemical tracer of sewage, and three classes of organic compounds in sediments. The results suggest that discharges from publicly owned treatment works are responsible for concentrations of the organic compounds encountered in the northeastern coastal region, while other sources may predominate in the other regions of the country.     

旅游规划中的创意景观设计——以崇州市鸿乐仙境创意景观工程设计为例

出色的景观设计是乡村旅游规划中的重要产品之一.以崇州市鸿乐仙境创意景观工程设计为例,提出了一种基于环境要素体系的创意景观工程设计方法和程序.     

泥石流防治工程信息系统初探

结合泥石流防治工程的特点与地理信息系统的特征,探讨构建了泥石流防治工程信息系统的框架,定义了信息系统基本数据库的属性及其特征,实现了部分模块.构建泥石流防治工程信息系统主要是要使泥石流防治设计做到科学、高效、可行、可靠,且经济节约.同时西部大开发过程中面临大量的泥石流防治设计任务,目前专业设计人员缺乏,工作量大,该系统可为设计人员提供参考评价的工作平台,促进泥石流防治工作的高效运行.     

Watershed management program on Santiago Island,Cape Verde

The Watershed Management Program (WMP) was put into operation in early 1985 on Santiago Island, Cape Verde, with the stated purpose, “to develop and protect the soil and water resources of the Program-designated watersheds … to stabilize the natural environment and increase agricultural production potential in the Program area.” The approach to soil and water conservation in the program has been to build erosion and flood control structures (engineering approach) and plant trees (biological approach) to decrease rill and gully erosion, trap sediment behind control structures, provide flood protection, increase infiltration, increase fuelwood and fodder production, and increase water supplies for irrigation. There have been many successes resulting from specific management activities, but flawed approach or implementation in a few key areas has acted to impede the program's complete success, including lack of a scientific basis for evaluating its impact on soil and water conservation; poor design, placement, and maintenance of some major hydraulic structures; inadequate intervention in stabilizing farmlands or education of farmers and landowners in the need for and benefits of agroforestry; and incomplete integration of engineering and biological approaches.