New generation water quality guidelines for ecosystem protection

1. Water quality guidelines are important for the management of water resources. Initially, guidelines focused on quality for domestic drinking water and for agricultural, recreational and industrial purposes. More recently, the emphasis has been on ecosystem protection, as well. 2. This paper discusses the key elements of new risk-based water quality guidelines being developed in Australia and New Zealand, that should lead to more effective management and protection of aquatic ecosystems. 3. There are three essential elements to this new approach: (i) it is ecosystem-based— ideally the guidelines should be, as far as possible, ecosystem-specific; (ii) it is issue-based— the guidelines should focus on the actual issues or problems caused by physical, chemical and biological stressors rather than on the individual indicators, as at present; and (iii) it is risk-based. There is generally great difficulty in deciding whether adverse biological effects will result from various stressors added to an ecosystem. The new approach develops guideline ‘packages’ for each issue and, where possible, for each ecosystem type. Each ‘package’ consists of specified key performance indicators, trigger levels for these indicators (that is, levels which indicate the degree of risk that adverse biological effects may occur), and for high risk situations (where trigger levels are exceeded) a protocol for considering the effect of ecosystem-specific factors in reducing (or enhancing) the biological effects. 4. This paper presents a case study related to a highly relevant aquatic ecosystem issue in Australia, namely the excessive growth of cyanobacteria (blue-green algal blooms), to illustrate how the new risk-based guidelines might be applied.     

Water Resources in Life-Cycle Impact Assessment: Considerations in Choosing Category Indicators

Water is one of many resources, wastes, and pollutants considered in life-cycle assessment (LCA). The widely used indicator for water resources, the total input of water used, is not adequate to assess water resources from a sustainability perspective. More detailed indicators are proposed for water resources in two areas essential to water sustainability: water quantity and water quality. The governing principles for a consideration of water quantity are that (1) the water sources or LCA inputs are renewable and sustainable and (2) the volume of water released or LCA outputs are returned to humans or ecosystems for further use downstream. The governing principle for a consideration of water quality is that the utility of the returned water is not impaired for either humans or ecosystems downstream. Water quantity indicators are defined for water use, consumption, and depletion to reveal the sustainable or nonsustainable nature of the sources. A flexible set of water quality indicators for various factors that may impair water quality are then discussed, including the LCA study choices, technical challenges, and trade-offs involved with such indicators. Indicator selection from this set involves the underlying concern or endpoint represented by the indicator and the level and accuracy of decision-making information that the indicator must provide. With significant differences in emissions among systems studied using LCA and different purposes of the LCA studies themselves, a single, default set of water quality indicators applicable to all systems studied with LCA is problematic. The proposed water quantity and quality indicators for LCA studies are also intended to be compatible with environmental management and reporting systems so that data needs are not duplicated and interpretation for one does not contradict or sow confusion for the other.     

基于陆地-水生态系统耦合的海河流域水生态功能分区

水生态功能分区是针对水生态系统特征的陆地生态系统划分,是为流域水生态管理提供生态背景和基本单元。陆地-水生态系统的耦合是水生态功能分区的核心,但多停留在个别小流域进行理论探讨,大型流域的实际案例较少。针对海河流域独特的气候、地貌、水文和人类活动特征,提出了水生态功能分区的三级指标体系。一级二级区针对气候、地貌、水文背景进行"自上而下"的分区,三级区针对人类活动对水资源、水环境、生境影响,采用"自下而上"的分区方法。最终,海河流域划分了6个一级区、16个二级区和73个三级区。研究充分体现了"以水定陆、以陆控水"的基本原则,以及"自下而上"和"自上而下"分区方法的优点,结果可为海河流域水生态管理提供科学依据,为水资源空间调配与合理利用、产业结构布局与区域协调等服务。     

淡水生态系统服务及其评价指标体系的探讨

对淡水生态系统的重要性及生态系统服务的内涵进行了阐述,指出了当前淡水生态系统服务研究的不足;认为淡水生态系统服务的正常发挥离不开一个健康的生态系统,但少有将两者结合的综合研究,而这样的研究又是必要的。水资源应明确包括水量、水质、水能和水生生物四大要素,以此为基础,对淡水生态系统服务及其评价指标体系进行了论述,并简要介绍其评价方法。文章还对国内相关研究的思路及其技术路线进行了探讨。     

The use of fish in ecological assessments

Abstract Fish provide powerful tools for assessing aquatic environments. Three attributes are especially significant: the sensitivity of fish to most forms of human disturbance, their usefulness at all levels of biological organization and the favourable benefit-to-cost ratio offish assessment programmes. Fish can be used as indicators over wide temporal and spatial ranges. Because they cover all trophic levels of consumer ecology, fish can effectively integrate the whole range of ecological processes in waterways. Fish have been used in many different roles for assessing river health and monitoring responses to remedial management. Three of these applications appear to have particular value for management of Australian rivers: (i) automated systems monitoring fish ventilation can provide sensitive, broad-spectrum and continuous sensing of water quality to protect receiving waters or water-supply intakes; (ii) programmes collecting routine data on commercial or recreational fisheries can be designed and analysed so as to isolate confounding effects due to fishery-specific factors and, hence, used to detect and monitor environmental change on large scales; (iii) the Index of Biotic Integrity (IBI) can be modified to suit Australian conditions and fish communities to meet the important need for a predictive model of aquatic environmental quality. The IBI is a quantitative biological tool with a strong ecological foundation that integrates attributes from several levels of ecosystem organization. Examples of the use of IBI elsewhere suggest its robustness, flexibility and sensitivity can cope effectively with the low diversity of the Australian fish fauna and the dominance of ecological generalists. A provisional structure is suggested for a test of the IBI in four riverine regions of New South Wales.     

The interaction between water movement,sediment dynamics and submersed macrophytes

Water movement in freshwater and marine environments affects submersed macrophytes, which also mediate water movement. The result of this complex interaction also affects sediment dynamics in and around submersed macrophyte beds. This review defines known relationships and identifies areas that need additional research on the complex interactions among submersed macrophytes, water movement, and sediment dynamics. Four areas are addressed: (1) the effects of water movement on macrophytes, (2) the effects of macrophyte stands on water movement, (3) the effects of macrophyte beds on sedimentation within vegetated areas, and (4) the relationship between sediment resuspension and macrophytes. Water movement has a significant effect on macrophyte growth, typically stimulating both abundance and diversity of macrophytes at low to moderate velocities, but reducing growth at higher velocities. In turn, macrophyte beds reduce current velocities both within and adjacent to the beds, resulting in increased sedimentation and reduced turbidity. Reduced turbidity increases light availability to macrophytes, increasing their growth. Additionally, macrophytes affect the distribution, composition and particle size of sediments in both freshwater and marine environments. Therefore, establishment and persistence of macrophytes in both marine and freshwater environments provide important ecosystem services, including: (1) improving water quality; and (2) stabilizing sediments, reducing sediment resuspension, erosion and turbidity.     

The Water Impact Index: a simplified single-indicator approach for water footprinting

Purpose

Along with climate change-related issues, improved water management is recognized as one of the major challenges to sustainability. However, there are still no commonly accepted methods for measuring sustainability of water uses, resulting in a recent proliferation of water footprint methodologies. The Water Impact Index presented in this paper aims to integrate the issues of volume, scarcity and quality into a single indicator to assess the reduction of available water for the environment induced by freshwater uses for human activities.

Methods

The Water Impact Index follows life cycle thinking principles. For each unit process, a volumetric water balance is performed; water flows crossing the boundaries between the techno-sphere and environment are multiplied by a water quality index and a water scarcity index. The methodology is illustrated on the current municipal wastewater management system of Milan (Italy). The Water Impact Index is combined with carbon footprint to introduce multi-impact thinking to decision makers. The Water Impact Index is further compared to results obtained using a set of three life cycle impact indicators related to water, from the ReCiPe life cycle impact assessment (LCIA) methodology.

Results and discussion

Onsite water use is the main contribution to the Water Impact Index for both wastewater management schemes. The release of better quality water is the main driver in favour of the scenario including a wastewater treatment plant, while the energy and chemicals consumed for the treatment increase the indirect water footprint and carbon footprint. Results obtained with the three midpoint indicators depict similar tendencies to the Water Impact Index.

Conclusions

This paper presents a simplified single-indicator approach for water footprinting, integrating volume, scarcity and quality issues, representing an initial step toward a better understanding and assessment of the environmental impacts of human activities on water resources. The wastewater treatment plant reduces the Water Impact Index of the wastewater management system. These results are consistent with the profile of the three midpoint indicators related to water from ReCiPe.     

国际主要医疗质量评价体系选择的临床指标及其共性

医疗质量指标是评估医疗机构的基础,很多国际机构和组织都制定了临床指标体系。通过分析国际5个主要的医疗质量评价体系（世界卫生组织、经济合作与发展组织、美国卫生服务与质量研究所、美国绩效科学研究中心、澳大利亚卫生服务标准委员会）所选择的临床指标,发现其共性在于：在选择临床指标时均高度重视临床服务的结果;高度重视临床指标的科学性和临床指标的可行性,其选择的临床指标中均包括住院死亡类指标,非计划重返类指标和患者安全类指标。     

Biospheric foundations of the ecosystem approach to environmental management

The ecosystem approach to environmental management inter-relates social, economic and environmental factors. Its incorporation into the Great Lakes Water Quality Agreement of 1978 changed the focus of the Agreement from water in a political context to politics in an ecosystem context. Because ecosystems are open and dependent on Biospheric processes for their continued operation, the Biosphere (global ecosystem) emerges as a globally integrating factor in ecosystem management. Influences leading to development of the ecosystem approach in the Great Lakes Basin included: a politically shared resource in jeopardy, pollution, a common drinking water source, common enemies, advances in ecosystem theory, citizen groups, international political institutions, common economic and cultural ties, and a sense of crisis. A rationale is presented for viewing nations as politically defined ecosystems.     

Progress and opportunities in advancing near-term forecasting of freshwater quality

Near-term freshwater forecasts, defined as sub-daily to decadal future predictions of a freshwater variable with quantified uncertainty, are urgently needed to improve water quality management as freshwater ecosystems exhibit greater variability due to global change. Shifting baselines in freshwater ecosystems due to land use and climate change prevent managers from relying on historical averages for predicting future conditions, necessitating near-term forecasts to mitigate freshwater risks to human health and safety (e.g., flash floods, harmful algal blooms) and ecosystem services (e.g., water-related recreation and tourism). To assess the current state of freshwater forecasting and identify opportunities for future progress, we synthesized freshwater forecasting papers published in the past 5 years. We found that freshwater forecasting is currently dominated by near-term forecasts of water quantity and that near-term water quality forecasts are fewer in number and in the early stages of development (i.e., non-operational) despite their potential as important preemptive decision support tools. We contend that more freshwater quality forecasts are critically needed and that near-term water quality forecasting is poised to make substantial advances based on examples of recent progress in forecasting methodology, workflows, and end-user engagement. For example, current water quality forecasting systems can predict water temperature, dissolved oxygen, and algal bloom/toxin events 5 days ahead with reasonable accuracy. Continued progress in freshwater quality forecasting will be greatly accelerated by adapting tools and approaches from freshwater quantity forecasting (e.g., machine learning modeling methods). In addition, future development of effective operational freshwater quality forecasts will require substantive engagement of end users throughout the forecast process, funding, and training opportunities. Looking ahead, near-term forecasting provides a hopeful future for freshwater management in the face of increased variability and risk due to global change, and we encourage the freshwater scientific community to incorporate forecasting approaches in water quality research and management.     

Biomanipulation of lake ecosystems: an introduction

SUMMARY 1. This paper is an introduction to a special issue of Freshwater Biology containing selected papers from an international symposium on Food Web Effects of Fish in Lake Ecosystems: Research Progress, Water Quality and Fisheries Management held from 31 May to 3 June 2000 in Rheinsberg, Germany. The primary goal of the workshop was to enlarge the current view of fish-induced effects on lake ecosystems. An additional goal was to promote biomanipulation as a multiple-use tool for managing freshwater ecosystems.
2. The three main topics addressed at the workshop were: (i) mechanisms involved in biomanipulation, (ii) whole-lake case studies and (iii) management aspects in water quality and fisheries.
3. Mortality of Daphnia , nutrient recycling, habitat selection and fish predation are reported as important mechanisms governing food-web effects as a result of biomanipulation.
4. Whole-lake case studies indicate that repeated fish removal can help improve water quality of shallow lakes, but successful biomanipulation of deep, thermally stratifying lakes remains difficult.
5. In many cases, biomanipulation of lakes has proved to provide benefits in addition to improving water quality. As all lake users are potentially affected when biomanipulation is used as a lake management tool, their concerns need to be clearly recognised if biomanipulation is to be successful in practice.     

Exposure Analysis of C8- and C9-Alkylphenols,Alkylphenol Ethoxylates,and Their Metabolites in Surface Water Systems within the United States

This study was conducted to develop a statistical understanding of exposures to C8- and C9-alkylphenol ethoxylates (APEO) and their metabolites (APEM) in U.S. surface waters. Concentrations of APEO/APEM (all analytes) in freshwater have been reported by 19 investigations over the past 15 years. Only limited data are available for sediments and marine ecosystems. Based on the frequency of detection in surface waters, 67% of all analytes were below their detection limits. Although maximum reported concentrations varied with time, the average and 90th centile concentrations have remained relatively constant. Examination of frequency distributions for nonylphenol (NP) concentrations indicated that 99% of the levels in fresh surface waters are below the U.S. Environmental Protection Agency's Aquatic Life Ambient Chronic Water Quality Criteria for NP (6.6 μg/L). A conservative evaluation of aggregated NPEO/NPEM concentrations suggested that 97% of the samples contained aggregate NP equivalent concentrations that are also below 6.6 μg/L. These results suggest that on a nationwide basis, the likelihood of surface water concentrations exceeding the chronic USEPA Water Quality Criterion for NP is low.     

Assessing freshwater use impacts in LCA: Part I—inventory modelling and characterisation factors for the main impact pathways

Background, aim and scope

Freshwater is a basic resource for humans; however, its link to human health is seldom related to lack of physical access to sufficient freshwater, but rather to poor distribution and access to safe water supplies. On the other hand, freshwater availability for aquatic ecosystems is often reduced due to competition with human uses, potentially leading to impacts on ecosystem quality. This paper summarises how this specific resource use can be dealt with in life cycle analysis (LCA).

Main features

The main quantifiable impact pathways linking freshwater use to the available supply are identified, leading to definition of the flows requiring quantification in the life cycle inventory (LCI).

Results

The LCI needs to distinguish between and quantify evaporative and non-evaporative uses of ‘blue’ and ‘green’ water, along with land use changes leading to changes in the availability of freshwater. Suitable indicators are suggested for the two main impact pathways [namely freshwater ecosystem impact (FEI) and freshwater depletion (FD)], and operational characterisation factors are provided for a range of countries and situations. For FEI, indicators relating current freshwater use to the available freshwater resources (with and without specific consideration of water ecosystem requirements) are suggested. For FD, the parameters required for evaluation of the commonly used abiotic depletion potentials are explored.

Discussion

An important value judgement when dealing with water use impacts is the omission or consideration of non-evaporative uses of water as impacting ecosystems. We suggest considering only evaporative uses as a default procedure, although more precautionary approaches (e.g. an ‘Egalitarian’ approach) may also include non-evaporative uses. Variation in seasonal river flows is not captured in the approach suggested for FEI, even though abstractions during droughts may have dramatic consequences for ecosystems; this has been considered beyond the scope of LCA.

Conclusions

The approach suggested here improves the representation of impacts associated with freshwater use in LCA. The information required by the approach is generally available to LCA practitioners

Recommendations and perspectives

The widespread use of the approach suggested here will require some development (and consensus) by LCI database developers. Linking the suggested midpoint indicators for FEI to a damage approach will require further analysis of the relationship between FEI indicators and ecosystem health.     

Water quality assessment in shrimp culture using an analytical hierarchical process

Water quality assessment is an important activity for controlling harmful crisis in aquaculture systems. The objective of our study was to develop a new Water Quality Index focused on monitoring of shrimp farms; detecting poor water quality and preventing negative effects in the ecosystem. Usually, several water quality parameters are monitored and measured in a shrimp farm during a farming period. Those parameters are classified according to their negative effects in the ecosystem and their respective allowed limits are also defined. The proposed Water Quality Index assigns a priority level to each water parameter through a new analytical hierarchical process (AHP), which allows an accurate assessment of the water quality. Our proposed index was applied to assess the water quality condition in extensive shrimp farms in Mexico. A comparison between our approach and those proposed in the literature shows its good performance when real environments are assessed.     

汉江上游金水河流域森林植被对水环境的影响

以汉江上游金水河流域为研究区域,分析了流域森林植被对水环境的影响。利用年降水量、林冠截留率和不同森林类型面积的数据,计算了金水河流域森林生态系统的水源涵养量,分析了流域森林植被对水量的影响;采用监测的方法,分别对金水河流域阔叶林森林生态系统的大气降水、枯落物层、土壤层和出口河水的水质进行了比较分析,探讨流域森林植被对水质的影响。结果表明,(1)金水河流域森林生态系统的水源年涵养总量为466.79×106m3,(2)流域阔叶林森林生态系统能够调节pH值,缓解大气降水的酸性环境;降低了大气降水中TDS、CODMn、HCO3、SO4、Cl、NO3、NH4-N、NO3-N、PO4-P、TDP、As、Ba、Cr、Na、Pb、Fe、K、Mn、V和Zn的含量,净化了水质。(3)根据各贮水层的水质分析,推断了河水中各物质的不同来源。研究为南水北调中线工程水源地的管理和建设提供了参考。     

Adding value to water resource management through biological assessment of rivers

Water resource management encompasses a variety of regulations and mandates relevant to water protection and restoration. Awareness of the value-added biological monitoring and assessment to water resource management is increasing worldwide, but especially in countries that have implemented proactive water law and regulatory frameworks for protection of surface waters. Biological communities provide an integrated response to pollutants and human disturbance within watersheds through their continuous exposure to the magnitude, duration, and frequency of stressors, and, thus, are important for assessing ecosystem health. The selection of proper bioindicators can provide additional benefits through their use in causal analysis of impaired waters and measurement of ecosystem recovery after restoration. A process for implementing biological indicators in a monitoring and assessment framework is outlined for managers and practitioners of water resource protection and restoration.     

Northern pike (Esox lucius L.) and aquatic vegetation,tools in the management of fisheries and water quality in shallow waters

Species and size composition of fish communities in shallow stagnant waters appear to be associated with the type, abundance and pattern of the vegetation. Man-induced impacts as eutrophication, and suppression of vegetation for reasons of water quantity management or angling pleasure may induce irreversible changes in the aquatic ecosystem. Water quality management should aim at restoring former pike habitat. Submerged weeds are important to that effect. These habitats are characterized by relatively low densities of fish stocks. Stocking of bream and carp interferes strongly with these objectives. With respect to fish stocks, interests of water quality and fishery management may be opposed.     

Physico-chemical and Water Quality Index analysis of the Okhuaihe River,Edo State,Nigeria

The water quality of the Okhuaihe River, Edo State, Nigeria was investigated from February to June 2016 to determine its suitability for drinking and other domestic purposes. Water samples collected from three stations were tested for fifteen physico-chemical parameters using standard analytical procedures. Biochemical oxygen demand and sodium were significantly different across the three stations. Except for calcium and iron, all other parameters were within the permissible limits recommended by the Nigerian Standard for Drinking Water Quality (NSDWQ) and World Health Organization (WHO). Water Quality Index (WQI) values ranged from 9.17 to 10.40, indicating excellent water quality. Although the quality of the water from the Okhuaihe River is suitable for drinking and domestic usage, regular monitoring of human activities along the water front and control of effluents discharged into the river is recommended to sustain and improve water quality.     

Ecological indicators for stream restoration success

Exploitation of freshwater resources is essential for sustenance of human existence and alteration of rivers, lakes and wetlands has facilitated economic development for centuries. Consequently, freshwater biodiversity is critically threatened, with stream ecosystems being the most heavily affected. To improve the status of freshwater habitats, e.g. in the context of the European Water Framework Directive and the US Clean Water Act, it is essential to implement the most effective restoration measures and identify the most suitable indicators for restoration success. Herein, several active and passive bioindication approaches are reviewed in light of existing legal frameworks, current targets and applicable implementation of river restoration. Such approaches should move from the use of single biological indicators to more holistic ecological indicators simultaneously addressing communities, multiple life stages and habitat properties such as water quality, substrate composition and stream channel morphology. The proposed Proceeding Chain of Restoration (PCoR) can enable the integration of natural scientific, political and socioeconomic dimensions for restoration of aquatic ecosystems and associated services. Generally, an analysis that combines target species-based active bioindication with community-based passive bioindication and multivariate statistics seems to be most suitable for a holistic evaluation of restoration success, as well as for the monitoring of stream ecosystem health. Since the response of biological communities to changing environmental conditions can differ between taxonomic groups and rivers, assessments at the ecosystem scale should include several levels of biological organisation. A stepwise evaluation of the primary factors inducing disturbance or degradation is needed to integrate increasing levels of complexity from water quality assessments to the evaluation of ecological function. The proposed PCoR can provide a step-by-step guide for restoration ecologists, comprising all planning steps from the determination of the conservation objectives to the use of ecological indicators in post-restoration monitoring.     

基于供需平衡的北京地区水生态服务功能评价

水生态系统的服务功能受到人类活动的严重胁迫和剧烈影响,对水生态服务功能的人类占用和胁迫效应进行研究具有重要意义.本文采用水当量方法,计算了1998-2007年北京地区人类活动对水生态服务功能的占用当量,并结合水资源供给量评价了人类活动对水生态系统的胁迫效应.结果表明：1）北京地区近10年人类活动的水当量超过其供给量的5～17倍;2）不同生态服务功能类型的水当量排序为：水环境净化>水资源供应>水生境维持>水安全调蓄;3）在时间序列上,水当量超过供给量的倍数呈先升后降的趋势,1999年的占用量超过其供给量的倍数最大.该研究揭示了北京地区人类活动对水生态系统服务的占用量远超过其可供给量,造成该地区水资源的过度占用,进而占用和影响其他地区的水生态服务功能.