1. DNA示踪系统在水环境保护中的应用

王阳

导读： 不同水体之间通过流动、入渗、蒸发等复杂水文地质过程相互交换，导致水环境中污染源的识别极为困难，加大了水环境保护的难度，致使水环境持续恶化。因此，水环境污染控制迫在眉睫，而如何定位污染源位置是水环境保护的前提和关键，也一直是世界各国科学家共同关注的热点问题。 DNA是生命系统的重要生物分子，主要功能是存储和编码基因信息。DNA的分子结构具有可设计性、多样性和多功能性等优点。这些独特理化和生物特性使得DNA纳米示踪系统能够全面克服传统示踪系统存在的不足。例如，DNA纳米示踪系统具有数量无限且独立可彼此区分、无环境背景值影响、运移和降解特性一致等诸多传统示踪剂所不具备的优点，并且环境友好，十分适合于研究复杂水文地质条件下的多污染源识别问题。 近期，天津大学化工学院仰大勇教授课题组提出了DNA示踪系统的设计、制作和检测方法。近些年，工业和农业污染物肆意向环境水体中排放，严重污染了有限的水资源。而且，不同水体之间通过流动、入渗、蒸发等复杂水文地质过程相互交换，导致水环境中污染源的识别极为困难，加大了水环境保护的难度，致使水环境持续恶化。因此，水环境污染控制迫在眉睫，而如何定位污染源位置是水环境保护的前提和关键，也一直是世界各国科学家共同关注的热点问题。 仰大勇教授课题组从DNA示踪剂的设计和制作方法入手，详细介绍了DNA示踪剂在序列设计、保护、信号读取等方面的重要内容，综述了其在水环境示踪研究领域中的应用情况，着重探讨了DNA示踪剂制作材料的选取、DNA分子的保护和环境影响效应等关键问题，并深入讨论了DNA示踪技术应用过程中可能困扰大家的问题，最后对DNA示踪技术未来主要研究内容的发展方向提出了思考。DNA示踪系统的建立为准确识别水环境中污染物的来源，从而制定有效的控制策略提供了新的思路。 在工厂、医院、社区、农场等可能存在排污的场所放置不同的DNA示踪剂，在河流下游取水样进行检测，通过qPCR分析DNA示踪剂的类型和数量，就可以定位污染物的来源和污染物排放量。 首先对DNA分子序列进行特异性设计，确保其无环境背景值影响，经过BLAST特异性比对后进行生物和化学合成；判断水环境状况，在相对清洁的水环境中可以进行直接投放应用，在水环境条件复杂的环境中，采用粘土、高分子聚合物或硅等材料对其进行保护后再投放应用。

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发布时间: 2018-07-19

2. 平头鲶鱼入侵五大湖

王阳

Abstract A detailed review of historical literature and museum data revealed that flathead catfish were not historically native in the Great Lakes Basin, with the possible exception of a relict population in Lake Erie. The species has invaded Lake Erie, Lake St. Clair, Lake Huron, nearly all drainages in Michigan, and the Fox/Wolf and Milwaukee drainages in Wisconsin. They have not been collected from Lake Superior yet, and the temperature suitability of that lake is questionable. Flathead catfish have been stocked sparingly in the Great Lakes and is not the mechanism responsible for their spread. A stocking in 1968 in Ohio may be one exception to this. Dispersal resulted from both natural range expansions and unauthorized introductions. The invasion is ongoing, with the species invading both from the east and the west to meet in northern Lake Michigan. Much of this invasion has likely taken place since the 1990s. This species has been documented to have significant impacts on native fishes in other areas where it has been introduced; therefore, educating the public not to release them into new waters is important. Frequent monitoring of rivers and lakes for the presence of this species would detect new populations early so that management actions could be utilized on new populations if desired. Keywords Flathead catfishPylodictis olivarisGreat LakesInvasive

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发布时间: 2018-07-17

3. 预测地中海最濒危的海洋无脊椎动物的命运：保护生物学中长期监测的力量

王阳

Global climate change and other human‐induced alterations of the environment are causing a significant loss in biodiversity. Among the many species affected is the giant limpet Patella ferruginea, considered as the most endangered marine invertebrate within the Western Mediterranean basin. The results of a 10‐year monitoring programme in an updated population viability analysis (PVA) model are provided, which indicate the unlikeliness of the population in Ceuta facing extinction within the next 50 years. Evidence is provided for the possible role of this population as a source population for other sink populations in the Alboran Sea. Large interannual variations in recruitment have been recorded, and the general linear model (GLM) indicates the influence of chlorophyll and temperature on recruitment rates. These results inform conservation strategies for this flagship species.

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发布时间: 2018-08-13

4. 澳大利亚渔业种群的快速下降证明”如果不扩大“禁渔”储备网络，将无法实现全球可持续性目标”

王阳

A continuing debate between environmental scientists and fisheries biologists on the sustainability of fisheries management practices, and the extent of fishing impacts on marine ecosystems, is unlikely to be resolved without fishery‐independent data spanning large geographic and temporal scales. Here, we compare continental‐ and decadal‐scale trends in fisheries catches with underwater reef monitoring data for 533 sites around Australia, and find matching evidence of rapid fish‐stock declines. Regardless of a high global ranking for fisheries sustainability, catches from Australian wild fisheries decreased by 31% over the past decade. The biomass of large fishes observed on underwater transects decreased significantly over the same period on fished reefs (36% decline) and in marine park zones that allow limited fishing (18% decline), but with a negligible overall change in no‐fishing marine reserves. Populations of exploited fishes generally rose within marine reserves and declined outside the reserves, whereas unexploited species showed little difference in population trends within or outside reserves. Although changing climate and more precautionary fisheries management contribute to declining fish catches, fisheries‐independent transect data suggest that excessive fishing also plays a major role. The large number of fishery stocks that remain unmanaged or have poor data, coupled with continuing declines in the stock biomass of managed fish species, indicate that Aichi Target 6 of the Convention on Biological Diversity (i.e. ‘by 2020, all fish and invertebrate stocks and aquatic plants are managed and harvested sustainably’) will not be achieved in Australia, or elsewhere. In order to maintain some naturally functioning food webs supported by large predators and associated ecosystem services in this era of changing climate, a greatly expanded network of effective, fully protected marine protected areas is needed that encompasses global marine biodiversity. The present globally unbalanced situation, with >98% of seas open to some form of fishing, deserves immediate multinational attention.

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发布时间: 2018-08-13

5. 弥合鸿沟： 海洋保护区网络设计中的社会生态一致性

王阳

Abstract Marine Protected Areas (MPAs) and networks of MPAs are being implemented globally as a spatial management tool for achieving conservation objectives. There has been considerable progress in reaching the prescribed 10% protected area target for 2020, outlined in the Convention on Biological Diversity Aichi Target 11 and the United Nations Sustainable Development Goal 14. The application of MPA network design principles (e.g. Representative, ecological connectivity), which underpin ecological coherence, is still lacking or insufficient in many regions. Poor ecological coherence hinders the ecological performance of MPA networks, leading to dysfunction in the flow of ecosystem services and reduced ecosystem benefits, with potentially negative consequences for human well‐being. This paper presents four pivotal focus points for future progress that can bridge the gap between ecological and social systems. The aim is to shift the discourse of ‘ecological coherence’ further into the social sphere, and hence support the alignment of the process of designating ecologically coherent MPA networks with the ‘triple bottom line’ of economic development, environmental sustainability, and social inclusion, as described in the Sustainable Development Goals (SDGs), to achieve social–ecological coherence in MPA network design.

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发布时间: 2018-08-13

6. 密歇根湖绿湾：大湖区恢复的试验场

王阳

Green Bay has sometimes been referred to as the largest freshwater “estuary” in the world. Its watershed, much of it in intensive agriculture, comprises one-third of the Lake Michigan basin and delivers one-third of the lake's total phosphorus load. At one time, the major tributary, the Fox River, was considered the most heavily industrialized river in North America, primarily from paper manufacturing. Deterioration in water quality and the loss of beneficial and ecological uses have been extensive and began well back into the last century. More recently, the bay has also become a test case for our resolve to remediate and restore ecosystems throughout the Great Lakes and elsewhere. Green Bay has stimulated a significant amount of widely relevant research on the fate and behavior of toxics, biogeochemistry, habitat, biodiversity, and ecological processes. The bay represents a true “proving ground” for adaptive restoration. Key findings of the recent summit on the Ecological and Socio-Economic Tradeoffs of Restoration in the Green Bay Ecosystem are summarized here. Foremost among recommendations of the workshop was the creation of a “Green Bay Ecosystem Simulation and Data Consortium” serving as a data clearing house, building upon the significant progress to date, and developing a modeling framework and visualization tools, furthering public outreach efforts, and ensuring a sustained growth in scientific expertise. Funding was estimated to be on the order of ~$15–20M over the next ~5?years – a modest investment relative to the value of the ecosystem and the long-term cost of inaction.

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发布时间: 2018-08-13

7. 大湖区鱼类监测计划的整合非靶向和靶向化学筛选

王阳

The Great Lakes are a vital resource for drinking water and recreation and provide a major fishery for millions of people. As part of the Great Lakes Water Quality Agreement, the US and Canadian governments have been charged with the protection of this system. Persistent, bioaccumulative, and toxic (PBTs) contaminants were found to be affecting the lake water quality as early as the late 1960s, and various programs sponsored by the US and Canada have been created to monitor PBTs such as polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs). These programs have refined measurement techniques to quantify trace level contaminants using a targeted analytical approach. However, new PBTs are being detected in the environment, and the traditional targeted methodology is inadequate for understanding the complex chemical mixture affecting Great Lakes wildlife. Fortunately, new analytical technologies are emerging that allow for comprehensive screening of PBTs beyond targeted methods. The current commentary presents an outline of a new framework for contemporary monitoring programs. The goal is to facilitate the compilation of legacy, emerging PBT, and archive PBT signatures by utilizing the basic practices of traditional targeted analysis. This example focuses on fish monitoring programs, and how they are ideally suited for legacy monitoring as well as data-driven discovery of new chemicals of concern.

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发布时间: 2018-08-13