鄱阳湖渔业资源的利用现状及其应采取的保护措施

本文简要介绍了鄱阳湖渔业资源的现状,分析了渔业资源存在的优势以及目前对其利用的不合理现象,并进一步从渔民思想的“惯性”、保护资源政策的落实情况、资源开发缺乏整体规划等方面分析了不合理利用渔业资源的深层次原因,文章的最后提出了保护鄱阳湖渔业资源的可行性对策。     

环艾比湖农场生态环境建设研究

艾比湖区生态环境极其脆弱，尤其建国以后的大规模开垦，减少了入湖水量，导致湖面萎缩，风沙危害严重，对沿岸团场的生产和生活产生了较大的影响，针对近年来日益严重的生态环境问题，对艾比湖流域自然资源的合理开发和利用，生态环境的防治与保护提出了相应的措施，搞好生态环境建设，对保证该区绿洲农业的可持续发展具有重要意义。     

Macrobenthic fauna in Thale Sap Songkla, a brackish lake in southern Thailand

The macrobenthic fauna in Thale Sap Songkhla was investigated at 2–3 month intervals from October 1991 to October 1993. The abundance of the benthic fauna ranged from 53 to 9529 individuals m^?2. The abundance and species composition were generally higher during the late southwest monsoon (October) than during the mid-northeast monsoon (December). One hundred and twenty-two species belonging to six phyla were found. Three major groups of macrobenthic fauna consisted of 44 species of Polychaeta (36%), 44 species of Crustacea (36%) and 28 species of Mollusca (28%). The other six species (5%) were minor groups belonging mainly to the Nematoda, Oligochaeta, Sipunculida and Pisces (fish larvae). The predominant polychaetes were Diopatra neapolitana and Heteromastus filiformis. Diopatra neapolitana was found only at two stations close to the sea (20–1440 individuals m^?2), while H. filiformis was found at all stations (6-2255 individuals m^?2). Apseudes sp. 1 (Tanaidacea), Apanthura africana (Isopoda), Amphipoda (many species) and Eupogebia sp. (Anomura) were the main groups of Crustacea. The most abundant crustacean was Apseudes sp. 1., with a maximum density of 5726 individuals m^?2. The dendrogram of Jaccard's coefficient shows two clusters of communities. An increase of polychaetes was observed in the second year of the study.     

River, reservoir and lake sediment contamination by heavy metals downstream from urban areas of Switzerland

This paper quantifies sediment contamination by heavy metals in four reservoirs and one lake located downstream from major urban areas in Switzerland. The waterbodies include the Wettingen Reservoir (located on the Limmat River downstream from Zürich), the Klingnau Reservoir (on the lower Aare River), the Wohlen Reservoir (downstream from Berne), the Verbois Reservoir (downstream from Geneva) and Vidy Bay (Lake Geneva, city of Lausanne). For all sediment cores and contaminants, a trend is observed from high contaminant values in the lower part of the cores, decreasing to lower concentrations in the upper part of the cores. However, for each site and each element, specific features are recognized. Applying the criteria of the Swiss ordinance on soil protection, all sediment cores must be classified as contaminated by one or more contaminants and at variable levels. From these data, it is concluded that: reservoirs and lakes located downstream from major urban centres in Switzerland have accumulated significant volumes of contaminated sediments in the past, representing the largest, but not the most intensely, contaminated sites on a national scale; the main environmental risk is remobilization of the contaminants and their return to the food chain, particularly by infiltration into the groundwater; and although the processes of remobilization are identified, the conditions of occurrence and the amplitude of the processes are still poorly known. Different options of reservoir and lake sediment management also are discussed and further research topics defined.     

Management criteria for lake ecosystems applied to case studies of changes in nutrient loading and climate change

The aim of this paper is twofold: to present and discuss practically useful management criteria from different perspectives of lake management (fishery, recreation, conservation, monitoring of water quality and use of water for irrigation and drinking), and to put these criteria into the context of a holistic lake ecosystem model, LakeWeb, which accounts for production, biomasses, predation and abiotic/biotic feedbacks related to nine key functional groups of organisms constituting the lake ecosystem. These are phytoplankton, benthic algae, macrophytes, bacterioplankton, herbivorous zooplankton, predatory zooplankton, zoobenthos, prey fish and predatory fish. The LakeWeb model also includes a mass‐balance model for phosphorus and calculates bio‐uptake and retention of phosphorus in these groups of organisms. It also includes submodels for the depth of the photic zone and lake temperature. The LakeWeb model is driven by few and readily accessible driving variables and it has been extensively tested and shown to capture fundamental lake foodweb interactions very well, which should lend credibility to the scenarios discussed in this paper regarding the conditions in Lake Batorino, Belarus. The LakeWeb model offers a tool to address important, often very complex, scientific problems in a realistic manner. The first scenario describes the changes after 1990 when there was a drastic reduction in the use of fertilizers in agriculture because of political changes and the corresponding changes in lake characteristics and foodweb structures utilizing the given management criteria. The second scenario describes, for comparative purposes, the probable alterations in the lake foodweb related to global climatic changes; in this case, warming and increased temperature variations. This study indicates that there are several similarities between eutrophication and increases in temperatures, which are discussed in this paper along with the mechanistic reasons related to such changes by using a set of general management criteria.     

对淮河下游治理形势和任务的几点认识

洪泽湖是黄河南下夺淮的产物。新中国成立后通过兴建一系列的控制工程，使其成为真正意义上的一座巨型平原水库，并对淮河下游地区防洪安全和水资源供给产生了巨大影响。深入研究淮河与洪泽湖的关系．对促进淮河下游治理具有现实的意义。     

太湖五里湖生态恢复的理论与实践

在针对太湖五里湖水质严重污染和生态严重退化的情况,从分析浅水湖泊生态恢复的理论入手,提出生态恢复过程中控源减污、生境改善、生态重建、稳态调控的四个关键步骤,评价了西五里湖生态恢复示范工程的效果,计算了示范工程区水生植物覆盖度和生物多样性指数,指出达到景观要求的草型清水稳态湖泊还需要一个漫长的演替过程。     

荆江与洞庭湖汇流区演变分析

 对荆江与洞庭湖汇流区的水沙过程变化及河道演变等进行了分析，认为其主要的影响因素是江湖关系的调整变化、洞庭湖人工围垦和泥沙淤积、江湖汇流区下游河道变化以及上游来水来沙变化等。可供江、 湖治理和三峡枢纽下游河道可能发生的演变及工程措施的研究参考。     

荆江—洞庭湖水沙数学模型研究

在对复杂的荆江—洞庭湖水系进行概化的基础上，根据其中各节点和湖泊的实际情况，建立了对整个荆江—洞庭湖水系进行模拟计算的复杂河网水沙数学模型。采用1996年的相关资料进行了验证，结果表明，模型计算值与实测值吻合较好，说明本文对荆江—洞庭湖复杂边界条件的概化，特别是对湖泊调蓄作用的处理是比较符合实际情况的，模型可以模拟边界条件复杂的河网。运用该模型，可以计算出整个荆江—洞庭湖区域的洪水演进、泥沙淤积和河床变形情况，可供防洪调度以及江湖治理部门参考。