Seasonal movements of shortnose sturgeon (Acipenser brevirostrum) in the Altamaha River,Georgia

Shortnose sturgeon (Acipenser brevirostrum) populations were decimated by a variety of anthropogenic activities throughout much of the 20th century. Understanding the spatial and temporal dynamics of spawning migrations within natal rivers is a critical information gap with regard to habitat protection and ultimately, species recovery. The objectives of this study were to document and describe seasonal movements of shortnose sturgeon in the Altamaha River system, Georgia. Passive acoustic telemetry was used to monitor the movements of 40 adult individuals from April 2011 through February 2014. Telemetry data revealed that during much of the year, the adults resided within the tidally influenced portion of the river, with most detections occurring near the freshwater–saltwater interface. Upstream movements to potential spawning habitat occurred during winter and early spring, and most fish returned to the lower estuary by April. Upstream migrations appeared to be triggered by environmental cues and were initiated when mean weekly temperatures in the lower Altamaha River were 11.6–16.9 °C. Unlike spawning migrations documented in northern rivers, the pattern of movement observed in this study was a single‐step migration without an apparent resting or staging period. Upstream migrations during nonspawning months were also observed and appeared to correspond with increasing discharge, which potentially resulted in increased channel navigability and habitat availability in nondrought years. This study further illustrates the clinal variations in life history typical of the species and may have important implications on river‐specific strategies for species recovery.     

长江经济带环境污染治理投资对生态效率的影响研究

环境污染治理投资是生态环境保护的资金来源，其投资规模和投资形式对生态效率产生着重大影响。本文构建生态效率测度指标和非期望的超效率SBM模型，测定了长江经济带9省2市的生态效率水平，再利用Tobit模型量化研究环境污染治理投资的总量及各投资形式对生态效率的影响程度，得出长江经济带环境污染治理投资对生态效率具有正向影响但影响程度一般，3种环境污染治理投资类型中的当年完成环保验收项目环保投资对生态效率影响程度最大且显著。     

黄河流域生态保护和高质量发展制约因素与对策——基于“要素-空间-时间”三维分析框架

针对黄河流域生态保护和高质量发展的国家重大战略需求,本文指出缓解生态系统负荷"过满状态"和发展的矛盾是黄河流域生态保护和经济社会发展的主要矛盾,推进社会经济生态转型是解决这一矛盾的根本出路。在此基础上,首先,提出"要素-空间-时间"三维分析框架,明确推进黄河流域社会经济生态转型、实现生态保护和高质量发展应运用这一框架;其次,识别出落后的社会经济物质代谢、低效的人与自然共生空间格局、低效的路径依赖是制约黄河流域社会经济生态转型、实现黄河流域生态保护与高质量发展的关键因素;最后,提出了推进黄河流域经济物质代谢转型、空间重构和路径创造的关键性战略对策,即:做实以水定城、以水定人和以水定产,加快建设能源互联网黄河流域,推进别具一格创新驱动发展,打造信息网络强河以及推进流域经济深度一体化全球化。本文对深刻认识和把握黄河流域生态保护和高质量发展机理和方略具有一定理论和现实价值。     

近50年大黑河流域气候水文要素变化趋势及突变分析

基于大黑河流域6个气象站1966～2013年气温、降水量、蒸发皿蒸发量、相对湿度和日照时数长期数据系列,采用气候倾向率和滑动t检验法分析了近50年大黑河流域气象要素的变化趋势及变异年份。结果表明,大黑河流域整体呈现暖干气候倾向,气温呈显著增高趋势,变化率为0.43～0.57℃/10a,气温增温变点大致出现了两次,分别在1986、1997年;降水量和蒸发量多呈不显著减少趋势,降水量先减(1981年)后增(1990年),蒸发皿蒸发量先减(1986年)后增(1996年);相对湿度、日照时数多呈显著减小趋势。     

五大发展理念视角下的南流江流域综合管理研究

随着"创新、协调、绿色、开放、共享"五大发展理念的提出,广西壮族自治区在新时期对重要江河的流域管理方面有了新的要求。为了适应新的发展理念,以南流江流域为例,开展了流域综合管理方面的专项分析研究。研究发现,南流江流域存在着水文灾害多发、环境污染较严重、地下水超采、水土流失等一些自然问题以及法律法规不健全、流域管理机构单薄、规划不完善、忽视公众力量和缺乏新技术支撑等一些社会管理方面的问题,在这种背景下以前的流域管理模式显然已不再适用。因此,针对研究结果,基于五大发展理念,借鉴国外成功的经验并结合南流江流域的实际情况提出了一些相应的对策与建议,以提升流域的综合管理水平。     

A comparison of Zayandehrood River water values for agriculture and the environment

River water management is challenging not only since they are open systems with changing physical structures, but also because the water values are mostly unknown over varied sectors. If policymakers grasp water values, water management will be more efficient. This research intends to examine the values of water in agriculture, which receives the most substantial portion of water resources, with the values of water in the environment in Isfahan located in the Zayandehrood River basin of Iran. The consequences of contingent valuation and production function methods revealed that per cubic metre value of water is 13 times higher in the environment than agriculture. The government should reconsider the higher value of the environment despite it is a non‐market value. The contingent valuation model additionally proved that women exhibited 21% more willingness to pay than men in order to protect the environment; however, they are paid less by 36%.     

Modeling surface water-groundwater interaction in arid and semi-arid regions with intensive agriculture

In semi-arid and arid areas with intensive agriculture, surface water-groundwater (SW-GW) interaction and agricultural water use are two critical and closely interrelated hydrological processes. However, the impact of agricultural water use on the hydrologic cycle has been rarely explored by integrated SW-GW modeling, especially in large basins. This study coupled the Storm Water Management Model (SWMM), which is able to simulate highly engineered flow systems, with the Coupled Ground-Water and Surface-Water Flow Model (GSFLOW). The new model was applied to study the hydrologic cycle of the Zhangye Basin, northwest China, a typical arid to semi-arid area with significant irrigation. After the successful calibration, the model produced a holistic view of the hydrological cycle impact by the agricultural water use, and generated insights into the spatial and temporal patterns of the SW-GW interaction in the study area. Different water resources management scenarios were also evaluated via the modeling. The results showed that if the irrigation demand continuous to increase, the current management strategy would lead to acceleration of the groundwater depletion, and therefore introduce ecological problems to this basin. Overall, this study demonstrated the applicability of the new model and its value to the water resources management in arid and semi-arid areas.     

Enhancing river model set-up for 2-D dynamic flood modelling

Flood hazard mapping is a topic of increasing interest involving several aspects in which a series of progress steps have occurred in recent years. Among these, a valuable advance has been performed in solving 2-D shallow water equations in complex topographies and in the use of high resolution topographic data. However, reliable predictions of flood-prone areas are not simply related to these two important aspects. A key element is the accurate set up of the river model. This is primarily related to the representation of the topography but also requires particular attention to the insertion of man-made structures and hydrological data within the computational domain. There is the need to use procedures able to 1) obtain a reliable computational domain, characterized by a total number of elements feasible for a common computing machine, starting from the huge amount of data provided by a LIDAR survey, 2) deal with river reach that receives significant lateral inflows, 3) insert bridges, buildings, weirs and all the structures that can interact with the flow dynamics. All these issues have large effects on the modelled water levels and flow velocities but there are very few papers in the literature on these topics in the framework of the 2-D modelling. So, in this work, attention is focused on the techniques to deal with the above-mentioned issues, showing their importance in flood mapping using two actual case studies in Southern Italy. In particular, the simulations showed in this paper highlight the presence of backwater effects, sudden and numerous changes in the flow regime, induced by the detailed river model, that underline the importance of using 2-D fully dynamic unsteady flow equations for flood mapping.     

城市河流系统治理策略在鹅颈水生态修复中的应用

在简要介绍城市河流系统治理策略的基础上，详细论述其在鹅颈水生态修复中的应用。鹅颈水治理以流域为空间单位，准确把握河流主要问题，综合考量水资源、水安全、水环境、水生态、水文化，坚持工程和非工程措施并重，分阶段逐步实现洪水风险管理、外源污染控制、河流水质修复、河流生态系统恢复的目标。结果表明，鹅颈水目前已基本消除黑臭，水质逐渐提升至国家地表水Ⅳ类水标准。提出进一步加强河流生态系统恢复、优化管理制度、逐步建立全过程和全指标生态监测评估体系、实施弹性管理等鹅颈水系统治理措施。     

贵州北盘江增殖放流效果评价

为了评估北盘江鱼类增殖放流效果,2017~2018年期间采用体外荧光、剪鳍、"T"型标三种标志方法对目标鱼类进行标志放流,通过集中捕捞方式进行回捕调查,集中捕捞时间为2017年7月、2018年8月,捕捞水域为董菁-马马崖-光照-善泥坡库区。结果表明,白甲鱼回捕率较高,为0.82%,其他鱼类均在0.5%左右,其中主要为低龄鱼类,高龄鱼类较少;董菁打邦河及各库尾水域物种丰富度较高,善泥坡高家渡码头和马马崖库区试验库尾物种多样性指数相对较低。建议在以后的增殖放流活动中,加大每年的监测频次。