Mathematical model for the ecosystem response of Lake Ladoga to phosphorus loading

The ecosystem response model described in this paper combines an ecosystem model and a three-dimensional circulation model of Lake Ladoga developed earlier by the authors. The ecosystem model describes the process of Lake Ladoga eutrophication, and its biological submodel describes changes in the phyto- and zooplankton. In the earlier model version, lake circulation was determined using a two-dimensional hydrodynamical model which was not completely adequate. The present model allows calculation of the distributions of phyto- and zooplankton and mineral phosphorus and nitrogen. One of its main advantages is that reliable computations of the ecosystem dynamics over an extended period of time are possible. The response of the ecosystem to different levels of phosphorus pollution loading and to weather conditions is studied.     

河湖生态系统生态用水优化研究——以滇池流域为例

生态需水是河流与湖泊生态系统健康的重要基础。湖泊流域的河流与湖泊生态系统之间存在密切的水量联系,目前对流域内生态用水的研究多为单一生态系统生态需水简单相加,忽略了河流和湖泊之间复杂的水量联系。基于河湖复合生态系统之间的水量联系构建了河湖生态系统生态用水优化模型,并以滇池为例分析了河湖生态系统生态用水规律。结果表明：湖泊流域中单一河流或湖泊生态需水计算结果不能满足复合生态系统的生态用水要求,需要综合考虑河流和湖泊之间的水量联系;在当前水质状况下,牛栏江每年的调水量不能满足滇池流域的生态用水要求;滇池流域水体污染对流域内生态用水影响较大,随着水体污染程度的下降,流域生态用水量和调水量呈指数下降,河流生态用水呈线性下降。     

Microbial ecology of the watery ecosystems of Evros river in North Eastern Greece and its influence upon the cultivated soil ecosystem

The aim of the present study was to evaluate the microbial ecosystem of cultivated soils along the Evros river in NE Greece. Evros river together with its derivative rivers constitute the capital source of life and sustainable development of the area. Along this riverside watery ecosystem systematic agro-cultures were developed such as wheat, corn and vegetable cultures. The evaluation of the ecosystem microbial charge was conducted in both axes which are the watery ecosystem and the riverside cultivated soil area. Considerable discrimination of water quality was observed when considering chemical and microbiological parameters of the Evros river ecosystem. Ardas river possesses a better water quality than Evros and Erythropotamos, which is mainly due to the higher quantities that these two rivers accumulate from industrial, farming and urban residues leading to higher degree of pollution.An increased microbial pollution was recorded in two of the three rivers monitored and a direct relation in microbial and chemical charging between water and cultivated-soil ecosystems was observed. The protection of these ecosystems with appropriate cultivated practices and control of human and animal activities will define the homeostasis of the environmental area.     

粤港澳大湾区水生态修复及展望

水是生态系统物质循环和能量流动的重要纽带,水生态系统修复在区域生态系统修复中起到关键作用。粤港澳大湾区剧烈人类活动对江河湖库生态系统造成破坏和干扰,江河湖库污染严重,水生物减少,导致流域水生态服务功能退化甚至丧失;从生态修复科学内涵出发,判断湾区水生态系统健康状况已处于非生物控制跃迁阈值之下;针对该形势,从工程建设、水环境治理、空间规划和管理机制四个方面,梳理湾区近期开展的与水生态修复相关的水生态文明建设、水污染防治行动计划、水生态空间划定和推进河长制等工作,并对其中用到的技术、指标和制度进行条理;然后以茅洲河流域综合治理和广东万里碧道作为水生态修复的点、面代表,从水生态修复的整体目标、采用的技术措施、效果评价的指标体系和管理制度方法等方面分析当前的工作现状;总结湾区现状水生态修复工作,认为湾区水生态系统的非生物修复阶段基本结束;基于生态系统修复理论结合湾区江河湖库生态系统特点,提出适合湾区的水生态修复框架,讨论水生态系统修复面临的问题和未来工作的展望,为大湾区水生态修复提供直接依据。     

河流污染底泥的生态修复

通过综合近几年国内外对河流污染的治理方法,介绍了河流污染底泥的污染类型及现状,说明目前河流污染的严重性和进行修复的重要性及迫切性;阐述河流底泥生态修复的主要内容,对生态修复做了简要解释;介绍了几种目前处于试验阶段的生态修复工程技术。河流生态修复的总体目标是恢复河流系统健康,实现人与河流的和谐共存。     

汉江中下游生态系统健康评价指标体系构建及其应用

水利工程建设影响了河流生态系统健康。为探究梯级水库、跨流域调水等水利工程建设对长江流域河流生态系统健康的影响,以汉江中下游为例,采用频次分析法和相关性分析法对评价指标进行筛选,用最小二乘法和熵系数法相结合的综合权重模型确定各评价指标权重,从整体性、稳定性及可持续性3个方面构建了河流生态系统健康评价指标体系,并利用赋分法进行河流健康评价。结果表明,汉江中下游河流健康评价指标体系包含流量过程变异程度、输沙量变化、河流连通性、富营养化状况、鱼类物种数等11个指标。评价结果显示汉江中下游河流生态健康状况表现出较强的空间异质性,且健康状况逐年降低。靠近丹江口水库的区域较好,越往下游越差。     

河道生态系统特征及其自净化能力研究现状与发展

河道生态系统包括河道水体和河岸带两大部分,具有净化水体、降低污染物浓度的功能.研究河道生态系统的自净化能力对河道生态系统的健康评价及水环境管理具有重要的意义.目前该领域的研究主要侧重于两个方面:一方面是运用水质模型的方法模拟评价河道水体的自净化能力,另一方面则是研究河岸植被缓冲带对净化水体的作用.系统总结了目前研究的特点与不足,指出了今后应该重视的研究领域,主要包括:(1)应加强研究陆地生态系统空间异质性对河道自净化能力的影响研究;(2)需要系统解剖河道剖面形态结构与空间布局对河道水质自净化能力的影响;(3)重视面向外部复杂环境的参数获取方法的研究;(4)综合河岸生态系统与河道水体生态系统,系统研究非点源污染在陆-水迁移和水体运移中河道生态系统自净化能力的时空变化特征,从而为开展河道生态系统健康评价,河道生态系统管理提供科学的依据.     

大辽河口水环境污染生态风险评估

河口生态系统位于河流入海口,是介于河流和海洋之间的生态交错区,也是人类活动集中的区域。针对目前河口生态风险研究较多沿用陆地生态系统模式,并忽略风险分布的空间异质性等问题,以大辽河口为研究区,建立具有针对性的河口区(河海交错区)生态风险评价模型,以盐度和污染源作为划分河口不同区段的主要因素,对不同水期大辽河口生态风险及其空间分布进行有效评估,探讨河口区生态风险时空分布差异规律。结果表明,大辽河口整体生态风险水平相对偏高(三时段风险平均值为0.56),在0至1的生态风险指数空间中超过中等风险水平;就时间尺度上而言,造成大辽河口区生态风险差异的主要原因是径流量;就空间尺度而言,大辽河口区生态风险空间分布受上游来水携带污染物、下游污染源排放以及入海口门段海水稀释作用三者共同影响。因此,从根本上讲,改善并提高河口区域的生态风险水平,应密切关注人类活动对河口态系统造成的不良影响,并应以提高整个流域整体生态状况为根本目标和途径,这样才有助于从根本上解决产生河口区域生态风险的环境问题。     

Effects of hydromorphological impacts on river ecosystem functioning: a review and suggestions for assessing ecological impacts

Because of the serious effects of pollution on water supply much closer attention has been paid to water quality than to other aspects of river integrity. However, channel form and water flow are relevant components of river health, and recent evidences show that their impairment threatens the services derived from them. In this article, we review the literature on the effects of common hydromorphological impacts (channel modification and flow modification) on the functioning of river ecosystems. There are evidences that even light hydromorphological impacts can have deep effects on ecosystem functioning, and that different functional variables differ in their responses. Three criteria (relevance, scale and sensitivity) in the selection of functional variables are suggested as a guide for the river scientists and managers to assess the ecological impacts of hydromorphological modifications.     

Diverse water quality responses to extreme climate events: an introduction

We synthesize and summarize main findings from a special issue examining the origins, evolution, and resilience of diverse water quality responses to extreme climate events resulting from a Chapman Conference of the American Geophysical Union (AGU). Origins refer to sequences of interactive disturbances and antecedent conditions that influence diversification of water quality responses to extreme events. Evolution refers to the amplification, intensification, and persistence of water quality signals across space and time in watersheds. Resilience refers to strategies for managing and minimizing extreme water quality impacts and ecosystem recovery. The contributions of this special issue, taken together, highlight the following: (1) there is diversification in the origins of water quality responses to extreme climate events based on the intensity, duration, and magnitude of the event mediated by previous historical conditions; (2) interactions between climate variability and watershed disturbances (e.g., channelization of river networks, land use change, and deforestation) amplify water quality ‘pulses,’ which can manifest as large changes in chemical concentrations and fluxes over relatively short time periods. In the context of the evolution of water quality responses, results highlight: (3) there are high intensity and long-term climate events, which can generate unique sequences in water quality, which have differential impacts on persistence of water quality problems and ecosystem recovery rates; and (4) ‘chemical cocktails’ or novel mixtures of elements and compounds are transported and transformed during extreme climate events. The main findings regarding resilience to extreme climate events are that: (5) river restoration strategies for reducing pollution from extreme events can be improved by preserving and restoring floodplains, wetlands, and oxbow ponds, which enhance hydrologic and biogeochemical retention, and lengthen the distribution of hydrologic residence times; and (6) the biogeochemical capacity for stream and river ecosystems to retain and transform pollution from landscapes can become “saturated” during floods unless watershed pollution sources are reduced. Finally, the unpredictable occurrence of extreme climate events argues for wider deployment of high-frequency, in situ sensors for monitoring, managing, and modeling diverse water quality responses. These sensors can be used to develop robust proxies for chemical cocktails, detect water quality violations following extreme climate events, and effectively trace the trajectory of water quality recovery in response to managing ecosystem resilience.     

Key factors determining water quality,fish community dynamics,and the ecological health in an Asian temperate lotic system

Identifying the key determinants and their impacts on water quality and fish community structure is imperative to environmental assessment and ecosystem conservation. The main objectives of this study were to assess the factors driving water quality, fish assemblages, and ecological health in a temperate lotic ecosystem using a long-term (12 years) dataset. The results indicate that sewage treatment plants significantly negatively impact river water quality and are primary pollution sources. Temporal fluctuations showed that the summer monsoon adversely influenced TN and EC due to dilution effects while increasing the COD and TSS in the water. Annual variations and the Mann–Kendall test demonstrated increasing trends in COD, TN:TP ratio, and CHL-a but a decreasing trend of TP with the impoundment. Artificial barriers (weirs) in the river created more favorable algal growth conditions due to increased water residence time. COD and TSS levels in the river were significantly affected by soil erosion. The environmental disturbance measures index indicated that all sites were severely degraded. Fish composition analysis suggested that exotic fish species such as, Lepomis macrochirus and Micropterus salmoides, dominated the community structure and negatively impacted native species after the installation of weirs. Our findings indicate that fish guilds and the IBI model are controlled by nutrient enrichment, organic matter, algal production, and land use/land cover. Water quality governs the biological health of the river. Overall, evaluation of the river's ecological health based on the multi-metric WPI and the IBI revealed that the river has a “poor” to “very poor” ecological status. The outcomes of this study may aid policymakers in managing and restoring the river.     

污染湖泊生态系统服务净价值评估——以滇池为例

水污染是我国湖泊生态系统面临的主要环境问题,评估污染条件下湖泊生态系统服务价值对认识和恢复污染湖泊生态功能具有重要意义。针对当前湖泊生态系统服务价值评估方法中未体现水污染负面影响的问题,在传统生态系统服务功能价值评估框架的基础上,将水污染造成的经济损失内化到生态系统服务功能价值中,提出了针对污染湖泊的生态系统服务功能价值评估方法。应用该方法核算了滇池生态系统服务净价值。结果表明:2006—2015年滇池年均生态系统服务功能价值为386.55亿元/a,水污染改变了滇池的价值结构,供水价值丧失,气候调节、旅游和蓄水等成为滇池生态系统服务功能价值的主体;滇池水污染对流域内外经济社会发展造成的损失达到15.23亿元/a,主要经济损失体现在生态补水费用和蓝藻去除费用;综合湖泊生态系统服务的正向价值和水污染的负向损失,滇池的净生态系统服务价值为371.33亿元/a,占流域GDP的11.7%。将水污染损失纳入湖泊生态系统服务功能价值评估中增强了评价结果的合理性,能够更加真实地反映湖泊生态系统对人类经济社会发展的综合影响。     

Impact of habitat fragmentation on genetic population structure of roach, Rutilus rutilus, in a riparian ecosystem

During the last 200 years, the riparianecosystem along major rivers has been reducedto a few scattered remnants. Important elementsof the riparian ecosystem are water bodieswhich were originally connected to the mainriver channel by annual floodings. Due to riverregulations many of these remnants are nowvirtually isolated. In an allozyme analysisusing roach, Rutilus rutilus, as a studyspecies we demonstrate that the geneticdiversity (number of alleles per locus,expected heterozygosity) of populations livingwithin floodplain water bodies is not severelyimpoverished compared to the genetic diversitywithin the main river channel. However, wefound slight differences in the allelefrequencies of flood plain water bodies and themain river channel. Nevertheless, fishpopulations in floodplain water bodies mayserve as reservoirs of autochthonous geneticmaterial for restoration of fish populations inthe main river channel after populationextinction due to catastrophic accidents (e.g.industrial pollution).     

Assessing water scarcity by simultaneously considering environmental flow requirements,water quantity,and water quality

Water scarcity is a widespread problem in many parts of the world. Most previous methods of water scarcity assessment only considered water quantity, and ignored water quality. In addition, the environmental flow requirement (EFR) was commonly not explicitly considered in the assessment. In this study, we developed an approach to assess water scarcity by considering both water quantity and quality, while at the same time explicitly considering EFR. We applied this quantity–quality-EFR (QQE) approach for the Huangqihai River Basin in Inner Mongolia, China. We found that to keep the river ecosystem health at a “good” level (i.e., suitable for swimming, fishing, and aquaculture), 26% of the total blue water resources should be allocated to meet the EFR. When such a “good” level is maintained, the quantity- and quality-based water scarcity indicators were 1.3 and 14.2, respectively; both were above the threshold of 1.0. The QQE water scarcity indicator thus can be expressed as 1.3(26%)|14.2, indicating that the basin was suffering from scarcity problems related to both water quantity and water quality for a given rate of EFR. The current water consumption has resulted in degradation of the basin's river ecosystems, and the EFR cannot be met in 3 months of a year. To reverse this situation, future policies should aim to reduce water use and pollution discharge, meet the EFR for maintaining healthy river ecosystems, and substantially improve pollution treatment.     

河流生态系统健康研究现状与展望——基于文献计量研究

河流生态系统健康是生态系统服务供给和流域可持续发展的基础,亟需从其内涵、影响、评价等方面进行系统归纳。运用文献计量梳理国内外文献,归纳了河流生态系统健康在河流自身、人类需求、管理目标3个方面的内涵;并从人类活动、土地利用、河流生境、水质、水量、气候变化等几个方面归纳了影响河流生态系统健康的主要因素和机理;明确了现有的河流生态系统健康评价方法,包括指示生物法、综合指标法、数学模型法等,总结了它们的优缺点和适用范围。最后,从河流生态系统健康的概念内涵、评价指标和水陆耦合等方面提出了存在的问题,建议进行流域整体的河流生态系统健康评价、跨区域的综合评价对比、多学科评价指标、河流廊道等几个方面的深入研究。     

流域生态系统服务和水土资源匹配研究进展

生态系统服务精确评估和水土资源匹配状态,对统筹流域山水林田湖草一体化保护和修复,以及构建流域国土空间开发保护新格局具有深远影响。以生态系统服务与水土资源的响应关系为出发点,系统梳理了流域生态系统服务评估及水土资源匹配研究现状。主要贡献包括：(1)筛选大尺度生态系统服务评估精确性方法及其优势阐述;(2)提出将信息熵理论与多目标优化相结合的水土资源匹配模型算法;(3)指出基于系统耦合协调理论进行流域生态系统服务与水土资源响应机理研究的必要性。研究以期阐明流域生态系统服务与水土资源的关联性及其响应机制,为最终实现流域“土地利用经济-生态效益最大、缺水总量最小”的过程目标导向和“生态系统服务效益最大”的结果目标导向,提供理论支撑和技术指导。     

Influence of anthropogenic pollution on content of essential polyunsaturated fatty acids in links of food chain of river ecosystem

In the course of monthly sampling in 2008–2010, two regions of the littoral of the Yenisei river were compared. One of these regions (conventionally pure) was situated upstream of Krasnoyarsk, while the other (conventionally polluted) was downstream of Krasnoyarsk. The concentrations of heavy metals, oil products, phenols, biogenic elements and essential polyunsaturated fatty acids (PUFAs) in various components of the river ecosystem were determined. It was discovered that the anthropogenic pollution causes a decrease in the resources of essential PUFA in the biomass of the upper links of the food chain of the river ecosystem.     

黄河流域湿地水鸟多样性保护对策

黄河是中华文明的发源地, 被誉为母亲河, 是两岸社会经济发展的保障, 切实保护好黄河流域湿地生态系统, 事关中华民族伟大复兴的千秋大计。黄河流域湿地总面积为391万ha, 其中80.4%分布在上游, 中游和下游分别仅12.5%和7.1%。黄河流域是东亚-澳大利西亚候鸟迁徙路线和中亚候鸟迁徙路线上水鸟的关键栖息地, 一些迁徙水鸟最关键的栖息地均分布在黄河流域, 如黑颈鹤(Grus nigricollis)、白鹤(G. leucogeranus)、丹顶鹤(G. japonensis)、斑头雁(Anser indicus)、大鸨(Otis tarda)、东方白鹳(Ciconia boyciana)、大天鹅(Cygnus cygnus)、疣鼻天鹅(C. olor)、青头潜鸭(Aythya baeri)等。尽管黄河流域湿地提供的水资源仅占全国的2%, 但维持着全国12%的人口饮水安全和15%的耕地用水, 湿地生态系统的脆弱性较高。截至2017年底, 黄河流域已建立各类湿地自然保护地230处, 其中国家公园2处、国家级自然保护区9处、地方级自然保护区68处、国家湿地公园145处、省级湿地公园6处, 湿地保护率达到65%, 高于我国湿地保护53%的平均水平。然而, 流域尺度现有水鸟生物多样性保护仍然面临不少挑战, 包括全球气候变化、水资源过度利用、水环境污染、栖息地丧失等。为此, 我们提出了建立以国家公园为主体的湿地保护地体系、开展濒危候鸟栖息地修复和强化黄河流域综合管理的体制机制建设等建议。     

Water quality changes of the river Meuse assessed by chironomid pupal exuviae

The chironomid fauna of the river Meuse in Belgium and The Netherlands was studied in order to determine spatial water quality variations. Because the river Meuse serves as a source for drinking water production for about five million people in Belgium and The Netherlands, water quality is an essential factor to be studied. From 1984 till 1989 pupal exuviae were collected. Water quality was assessed by several indices and autecological information of the various taxa. With regard to pollution the general trend through the years was the same. The most upstream sampling site, in the Belgian Ardennes, was relatively unpolluted. As a result of untreated industrial and municipal wastewater discharges in the Liège region, water quality deteriorated dramatically at the Dutch border. At the most downstream sampling site, near the river mouth, a slight recovery was observed. Apart from organic and inorganic pollution other environmental factors such as flow velocity and the nature of the riverbed, also play a significant role in the occurrence of the organisms. It is concluded that protective measures need to be taken to restore the affected river ecosystem.The editors deeply regret to have to announce that Nicole Frantzen died in a train accident on 30 November 1992.     

浑河河水及其沿岸地下水污染特征

选择沈阳地区重要河流浑河及其沿岸地下水进行定量分析,研究并探讨了包括无机物和有机物在内的水质综合污染特征。结果表明,浑河河水中氨氮、硝氮、亚硝氮和酚超过了地表水环境质量标准,最大超标倍数分别为15.8、1.5、82.4和1.8倍,检测出的11种卤代烃、氯苯和六六六等有机物均未超标。浑河沿岸地下水中氨氮、硝氮、亚硝氮、化学需氧量、酚和铅超过地下水质量标准,超标率分别为31.6%、10.5%、26.3%、36.8%、47.4%和26.8%,检测出的4种卤代烃和六六六等有机物均未超标。河水及其沿岸地下水中的污染物,尤其是有机污染物种类和浓度高值基本出现在城西的谟家—大祝断面之间。浑河水质主要受城市工业废水、居民生活污水排放的影响,沿岸地下水的污染来源包括工业生产或农村居民生活造成的地表污染物垂直入渗式的点源污染、浑河水侧向渗透补给式的线源污染以及农药化肥使用产生的面源污染,而有机污染物主要通过点源污染地下水。浑河各区段的使用功能、包气带岩性及沿岸水源地开采井布局等因素都为受污染的河水对沿岸几百米范围内的浅层地下水的补给提供了条件,造成浅层地下水的污染,对当地生态系统及人类健康构成潜在威胁。