Anthropogenic transformation of the aquatic ecosystem of the Lower Volga

Many-year (1981–2009) variations of hydrochemical and hydrobiological characteristics of the state of the aquatic environment in the Lower Volga are presented. The development and transformation of the structural organization of aquatic organism communities are considered against the background of a tendency toward the accumulation of key pollutants and the regional features of those processes are considered. The study has shown that the aquatic ecosystem of the Lower Volga functions with its ecological state disturbed because of the strengthening of ecological regress.     

Priority Toxicants in Elements of Lower Don Ecosystem

Water Resources - The main sources of pollutants entering the Don R. ecosystem in its lower reaches are discussed. The principal sources are navigation, construction of new berths, dredging...     

酸雨对水生态系统中一些生物的影响

本文综述酸雨对水生态系统中各营养级生物的影响。介绍酸雨引起水体酸化和水体的缓冲能力,阐述不同营养级水生生物和所处不同发育阶段对低pH的敏感性差异。还讨论了由于遗传和适应引起生物对低pH的耐受性差异。酸化水体生物群落的重要特征是,生物种类数减少,多样性降低,生物量减少和食物链遭破坏。酸性pH对水生生物的毒作用方式包括气体交换受阻、体盐调节紊乱、酸碱平衡失调,以及与金属的联合作用等.最后还对若干问题作了扼要讨论,并提出建议。     

酸雨对水生态系统中一些生物的影响

本文综述酸雨对水生态系统中各营养级生物的影响。介绍酸雨引起水体酸化和水体的缓冲能力,阐述不同营养级水生生物和所处不同发育阶段对低pH的敏感性差异。还讨论了由于遗传和适应引起生物对低pH的耐受性差异。酸化水体生物群落的重要特征是,生物种类数减少,多样性降低,生物量减少和食物链遭破坏。酸性pH对水生生物的毒作用方式包括气体交换受阻、体盐调节紊乱、酸碱平衡失调,以及与金属的联合作用等.最后还对若干问题作了扼要讨论,并提出建议。     

福建敖江流域水域生态系统健康评估

以敖江流域为研究区,通过采集底栖动物、鱼类等样品,结合监测数据分析流域水域生态系统健康状况,并采用指标体系评估方法对水域生态系统进行评估.结果表明:敖江流域水质总体良好,但山仔水库总氮、总磷浓度长期超标,水体存在富营养化和藻类水华暴发生态环境问题;底栖动物种类呈现支流多于干流、河流多于水库的规律;鱼类种类上、中、下游各科物种组成差异不显著,鱼类区系特点具有较明显的热带、亚热带区系特点;流域上游、中游水域生态健康良好,下游水域生态健康一般.     

水生态评价方法研究进展及展望

水生态系统是人类赖以生存的基础,近年来气候变化和水资源开发、水体污染、过度捕捞等人类活动导致水生态系统严重受损,水生态系统的保护和修复已成为全球面临的重大挑战。科学合理的水生态评价方法是实现水生态系统稳定、健康和可持续管理的基本保障,也是目前我国各相关管理部门高度重视的关键问题,多个部门围绕水生态评价展开了积极探索与实践。本文系统回顾了水生态评价方法的发展历程并阐释了水生态评价的内涵,梳理了常用的水生态评价方法,明晰了各方法的基本理念和应用场景,分析了各方法的优点和不足,提出了基于生态完整性的水生态健康评价方法,最后对目前我国水生态评价需进一步完善的工作进行了展望。本文以期与相关领域研究者和管理者在水生态评价理论和方法方面进行探讨,为我国水生态考核工作提供理论支持。     

Multifractal principles of aquatic ecosystem development control by algacenosis correction

A method is proposed for the simulation and analysis of the processes of rehabilitation of water bodies based on the construction of their multifractal models, accounting for the heterogeneity of the inclosing ecosystem. It is proposed to assess the integral response of the ecosystem to control actions by imposing its multifractal image onto selected forms of critical organization, corresponding to the limits of self-recovery of water body structure.     

水生生态系统蓝藻固氮作用研究进展与展望

固氮蓝藻在水生生态系统中占优势是由多种因素所引起的,如营养盐浓度及形态、氮磷比、水温和微量元素等.一般认为,湖泊中正磷酸盐浓度≥0.01 mg/L、溶解性无机氮浓度≤0.1 mg/L时,固氮蓝藻出现,并且低的氮磷比是表征水体中固氮蓝藻出现的重要指标,但引起固氮与非固氮蓝藻分异的驱动机制还需要深入研究.此外,光照、无机氮浓度与形态、异形胞丰度和溶解性有机物对蓝藻固氮速率有重要影响,进而决定蓝藻氮释放通量及对水体中氮库的贡献作用.固氮蓝藻是贫营养盐海域和海洋生态系统中氮库的重要贡献者,但在富营养化湖泊中,其贡献作用还存在争议.因此就目前国内外对固氮蓝藻相关研究做综述,以期待业界同行能够对蓝藻固氮作用及其氮释放对水生生态系统中氮循环的贡献引起重视.     

秋季太湖水下光场结构及其对水生态系统的影响

水生态系统中光能的分配很大程度上决定了水生态系统的结构和功能,利用2007年11-12月太湖水体光学特性和组分浓度数据,对秋季太湖水下光场结构特征和水体组分光竞争能力的表征光学量(漫衰减系数、平均余弦)和影响因素(吸收系数比重)进行了分析研究.结果表明,秋季太湖水下辐照度呈现单峰分布,最高值为583nm左右:根据Kd可将黄质和非色素物质主导程度的强弱分为弱、较强、强三个等级;Kd(PAR)平均值为4.61±1.54m-1,水体真光层厚度平均值为1.11±0.35m;太湖水下光场的光能主要分布在青光和黄绿光波长范围内,约占总能量的60%,蓝光和红光波长范围内的能量约占30%,这样的光谱结构有利于铜绿微囊藻和斜生栅藻的生长.     

Environmental regulation of the chemical pollution in aquatic ecosystem (biological aspects)

The basic principles of the environmental regulation of anthropogenic impact on water bodies were discussed in this paper. Importance of the biological approach to pollution regulation in aquatic ecosystems was shown. The environmental regulation of the chemical pollution in aquatic ecosystems is based on the methodology of environmentally acceptable exposure levels.     

洪泽湖健康水生态系统构建方案探讨

洪泽湖生态系统健康状态为中等,并呈逐年退化的趋势,因此开展洪泽湖健康水生态系统构建方案的研究十分必要.本文分析了洪泽湖水生态系统健康状态、水体分区特征以及存在的主要问题,根据水文条件和水生态状况的差异,将洪泽湖划分为3种具有典型特征的湖区:过水通道(从淮河入湖口至入江水道)、湿地保护区和成子湖区.针对不同湖区在水质、水...     

Biotesting in the Assessment of Environmental and Toxicological State of Water Bodies in Lower Don River Basin

The toxicity of river water in the Lower Don basin was studied using biotesting with different biological objects. Water taken from most examined reaches of the Don and its tributaries was shown to exert toxic effect on crustaceans, algae, protozoa, and Rotifera.     

太湖东部不同类型湖区底泥疏浚的生态效应

为研究底泥生态疏浚对太湖东部不同类型湖区水生生态系统的影响,2012年8月于东太湖养殖湖区和胥口湾草型湖区采集沉积物和生物样品,分析疏浚对底泥污染控制、水质改善以及各生物群落结构的影响.结果表明,底泥疏浚能有效去除表层沉积物中的营养物质,降低底泥重金属含量及其潜在生态风险,但底泥疏浚对不同类型湖区水质和生物群落结构的影响存在明显差别.在富营养化较严重的东太湖养殖湖区,底泥疏浚达到了一定的改善水质的效果,浮游植物密度、生物量均不同程度降低,且群落中蓝藻所占比例下降;水生植物和底栖动物群落也在较短时间内得到恢复;胥口湾草型湖区的底泥疏浚则破坏了原先良好的水生植物群落,造成湖区整体水质下降,各主要生物类群的恢复相对缓慢.     

Recent aquatic ecosystem response to environmental events revealed from Pb sediment profiles

The ²¹⁰Pb dating method was first introduced by Goldberg (1963), and since then has been applied to study sediment from lakes, estuaries and coastal marine environments. Hundreds of studies around the world have used ²¹⁰Pb as a geochronological tool in aquatic ecosystems. However little attention has been paid to the potential of this naturally occurring isotope as an environmental tracer of ecological events. Here we report three instances in which ²¹⁰Pb profiles measured on undisturbed sediment cores from lakes, rivers and fjords show us the potential of ²¹⁰Pb profile as a tracer of natural and anthropogenic processes. The methodology used here is a suite of techniques combining biogeochemistry (micro-electrodes), paleomagnetism (susceptibility), sediment characteristics (LOI) and visualization (SPI and X-ray) applied to the interpretation of ²¹⁰Pb profiles. We measured ²¹⁰Pb profiles on sediments from a river, Cruces River (Chile), which recorded a clear shift in the water chemistry caused by a pulp mill effluent to the river. Here metal mobilization and remobilization of the tracer may be the cause of the observed profile. We also measured ²¹⁰Pb profiles in sediment from two fjords of Southern Chile (Pillan and Reñihue), the sudden deposition change of fresh ²¹⁰Pb with depth observed could very well be the result of bioturbation but it occurred in a seafloor area deprived of bioturbators. In this case, ²¹⁰Pb recorded the onset of aquaculture activities (fish farming) that took place two decades ago. Finally, ²¹⁰Pb profiles measured in two lakes in the “pampa Argentina”: Epecuen and Venado showed a particular shape with depth. These profiles apparently registered a sudden depositional event with recent ²¹⁰Pb material, probably related to strong shifts in precipitation and drought cycles in that part of the world. These three examples show that ²¹⁰Pb profiles provide valuable information not only on geochronology, but also related to natural and anthropogenic short term processes, as shown here, but these are not always reported and well understood.     

2009年秋季武汉大东湖北湖水系水生植物调查

武汉大东湖北湖水系包括北湖、严西湖、严东湖、竹子湖、清潭湖.2009年秋季对北湖水系湖区水生植物调查结果表明,水生植物分布面积达3.89km2,占整个水域面积的14.8%,总现存量(鲜重)为17834.28t;现有水生植物49种,隶属于20科36属,苦草(Vallisneria spiralis)、穗花狐尾藻(Myri...     

近十年青海湖水生态系统生产总值变化及其影响因素

受气候变化和人类活动影响,湖泊水生态系统及其服务功能发生改变,研究湖泊水生态系统生产总值动态变化及其影响因素,对于维护湖泊健康生命、实现湖泊功能永续利用具有重要意义。选择位于气候敏感区和生态脆弱区的青海湖作为研究对象,根据青海湖水生态系统特征及当前保护状况,筛选调节服务及文化服务2类8个评估指标,构建湖泊水生态系统生产总值指标体系,核算2010—2020年青海湖水生态系统生产总值,分析其变化趋势及主要影响因素。结果表明,2010—2020年青海湖水生态系统生产总值总体呈波动上升趋势,变化范围为6903.47亿～7848.55亿元;调节服务是青海湖水生态系统主要的服务类型,占比高达91%。近十年,气候调节和水质净化价值有所减少,其他服务功能价值均呈增加趋势。水源涵养价值增加最多,增长760.70亿元;气候调节价值下降最多,减少658.59亿元。偏最小二乘回归分析表明,水温、水位是影响青海湖水生态系统生产总值的主要因素。气候变化影响下,水温升高引起初级生产力增加及鱼类数量增长,同时近年来水体矿化度下降有利于水生生物生长,提高了固碳释氧和物种保育价值。水位与水面面积增加引起水源涵养、洪水调蓄...     

Modeling the succession of diatomic complex under growing industrial load on an aquatic ecosystem

Analysis of paleolimnological data on a part of Lake Imandra (Kola Peninsula), polluted by wastewaters discharged from a copper-nickel plant, is used to calculate the vertical profile of toxicity of bottom sediments and determine the response of dominant species of diatomic complex to the growing toxicity. The species are aggregated by the similar responses to the load. The dependence between the population sizes of diatom groups and toxicity is established. The diatom complex is shown to change its structure twice—at the toxicity exceeding the background level by factors of 1.2 and 3.2, respectively. A model is developed to describe variations in the species composition of the community under growing toxicity; the model is shown to be applicable to the analysis of paleolimnological data. General analysis of the model is given, and typical scenarios of variation in the number of species under growing toxic load are described.