General trends in freshwater ecological restoration practice in China over the past two decades: the driving factors and the evaluation of restoration outcome

Abstract Background Although freshwater ecological restoration (FER) has undergone an immense development over the past two decades in China either in the number of projects or in the spatial scale of implementations, a dearth of clear and comprehensive trends in this field is still a particular concern. We conducted a literature survey through searching the database of Web of Science between 1997-2017 to investigate the driving force behind FER practice and to summarize the restoration outcomes. Results A total of 2047 publications were hit and 198 of them were finally retained after manual screening. The number of studies in this field has been steadily increasing in recent years and their provincial distribution is positively correlated with GDP growth and the investment to pollution control and environmental protection, suggesting that economic development is a key driving factor of FER practice. Among the remained articles, nearly half (46.5%) focus on lake ecosystems, and 34.8% and 32.8% of the studies indicate that land reclamation and eutrophication are the predominant causes of freshwater ecosystem degradation. The overarching target of the restoration is biodiversity increase (31.4%), followed by water quality improvement (24.7%) and ecosystem services (23.9%). Revegetation is a dominant restoration approach (40.9%). Reference sites for assessment of restoration projects are normally control locations without intervention (60%), or the status of the targeted sites before the interventions. For the restoration outcome evaluation, 86% of the studies present positive outcomes in terms of water quality improvement, and 79% have improvement in biological features. The most frequently monitored organisms are macrophytes (31%), followed by benthos as indicators of ecological condition. Conclusions Economic growth, water pollution and investment into environmental protection are the main driving factors of FER practice in China. The effort of restoration and evaluation over the past two decades has not been limited to improving hydrological function and water quality, but also pay increasingly more attention to biological processes and ecological integrity, and further the ecosystem services in recent years. However, the lack of long-term monitoring and socioeconomic attributes considered in restoration success assessments are still particular issues needed to be addressed in the future FER researches and projects.

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General trends in freshwater ecological restoration practice in China over the past two decades: the driving factors and the evaluation of restoration outcome

10.21203/rs.2.19860/v1 ◽

2020 ◽

Author(s):

Juan Wu ◽

Yanran Dai ◽

Shuiping Cheng

Keyword(s):

Water Quality ◽

Quality Improvement ◽

Ecosystem Services ◽

Ecological Restoration ◽

Land Reclamation ◽

Outcome Evaluation ◽

Driving Factors ◽

Freshwater Ecosystem ◽

Water Quality Improvement ◽

The Past

Abstract Background Although freshwater ecological restoration (FER) has undergone an immense development in China either in the number of projects or in the spatial scale of implementations, a dearth of clear and comprehensive trends in this field is still a particular concern. We conducted a literature survey through searching the database of Web of Science between 1998-2017.Results A total of 2047 publications were hit and 198 of them were finally retained after manual screening. The number of studies in this field has been steadily increasing in recent years and their provincial distribution is positively correlated with GDP growth and the investment to pollution control and protection, suggesting that economic development is a key driving factor of FER practice. Among the remained articles, nearly half (46.5%) focus on lake ecosystems, and 34.8% and 32.8% of the studies believe that land reclamation and eutrophication are the top two causes of freshwater ecosystem degradation. The overarching target of the restoration is biodiversity increase (31.4%), followed by water quality improvement (24.7%) and ecosystem services (23.9%). Revegetation is the dominant restoration approach (40.9%). Reference sites for assessment of restoration projects are normally control areas or locations without intervention (60%), or the status of the targeted sites before the interventions. For the restoration outcome evaluation, 86% of the studies present positive outcomes in terms of water quality improvement, and 79% have improvement in biological features. The most frequently monitored organisms are macrophytes (31%), then followed by benthos as indicators of ecological condition.Conclusions The literature research indicated that economic growth, water pollution and investment into environmental protection are the main driving factors of FER practice in China. Additionally, the effort of restoration and evaluation over the past two decades has not been limited to improving hydrological function and water quality, but also pay increasingly more attention to biological processes and ecological integrity, and further the ecosystem services in recent years. However, the lack of long-term monitoring and socioeconomic attributes considered in restoration success assessments are still particular issues needed to be addressed in the future FER researches and projects.

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EFFICACY OF PHRAGMITE KARKA PLANT IN CONSTRUCTED WETLAND SYSTEM

International Journal of Research -GRANTHAALAYAH ◽

10.29121/granthaalayah.v3.i9se.2015.3177 ◽

2015 ◽

Vol 3 (9SE) ◽

pp. 1-5

Author(s):

Shalini Saxena

Keyword(s):

Water Quality ◽

Wastewater Treatment ◽

Quality Improvement ◽

Constructed Wetland ◽

Flood Control ◽

Water Quality Improvement ◽

The Past ◽

Wetland Treatment ◽

Natural Wetlands ◽

Wetland System

Wetlands, either constructed or natural, offer a cheaper and low-cost alternative technology for wastewater treatment. A constructed wetland system that is specifically engineered for water quality improvement as a primary purpose is termed as a ‘Constructed Wetland Treatment System’ (CWTS). In the past, many such systems were constructed to treat low volumes of wastewater loaded with easily degradable organic matter for isolated populations in urban areas. However, widespread demand for improved receiving water quality, and water reclamation and reuse, is currently the driving force for the implementation of CWTS all over the world. Recent concerns over wetland losses have generated a need for the creation of wetlands, which are intended to emulate the functions and values of natural wetlands that have been destroyed. Natural characteristics are applied to CWTS with emergent macrophyte stands that duplicate the physical, chemical and biological processes of natural wetland systems. The number of CWTS in use has very much increased in the past few years. The use of constructed wetlands is gaining rapid interest. Most of these systems cater for tertiary treatment from towns and cities. They are larger in size, usually using surface-flow system to remove low concentration of nutrient (N and P) and suspended solids. However, in some countries, these constructed wetland treatment systems are usually used to provide secondary treatment of domestic sewage for village populations. These constructed wetland systems have been seen as an economically attractive, energy-efficient way of providing high standards of wastewater treatment by the help of Phragmite karka plant. Typically, wetlands are constructed for one or more of four primary purposes: creation of habitat to compensate for natural wetlands converted for agriculture and urban development, water quality improvement, flood control, and production of food and fiber.

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What Price for Ecosystem Services in China?

Advances in Business Strategy and Competitive Advantage - Managerial Strategies and Solutions for Business Success in Asia ◽

10.4018/978-1-5225-1886-0.ch010 ◽

2017 ◽

pp. 176-198

Author(s):

Haixia Zheng ◽

Stale Navrud ◽

Shiran Shen

Keyword(s):

Water Quality ◽

Quality Improvement ◽

Ecosystem Services ◽

Water Resources ◽

River Basin ◽

Contingent Valuation Method ◽

Policy Instrument ◽

Miyun Reservoir ◽

Water Quality Improvement ◽

Value Of Water

Payment for Environmental Services (PES) in the watershed has been widely adopted as an important policy instrument to compensate upstream water users for providing water quality improvement for the whole river basin. In this paper, we use three independent valuation methods to determine the price of ecosystem service (ES), particularly water quality, in Miyun Reservoir, the main surface water source for Beijing. We find that the value of water quality is lowest using opportunity cost of limitation of development rights (OCLDR), highest with contingent valuation method (CVM), and water resources benefits assessment (WRBA) gives an in-between value. OCLDR determines the size of subsidies from those that benefit from water quality improvement from upstream. WRBA is a reference for compensation criteria to the upstream government and farmers when water resources are transferred across jurisdictional boundaries. CVM not only captures the direct value of water quality improvement, but also the indirect value of improvement in other ecosystem services as a result of improvement in water quality. Based on the results, we propose a multi-level ecological compensation system for the Miyun Reservoir river basin. We use OCLDR to determine subsides/ compensation to upstream farmers and other suppliers of the ES; WRBA set the price of water transfer; and CVM to figure out the size of payments for integrated water quality improvement.

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The Hydraulic Driving Mechanisms of Cyanobacteria Accumulation and the Effects of Flow Pattern on Ecological Restoration in Lake Dianchi Caohai

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph16030361 ◽

2019 ◽

Vol 16 (3) ◽

pp. 361 ◽

Cited By ~ 3

Author(s):

Peng Zhang ◽

Rui-Feng Liang ◽

Peng-Xiao Zhao ◽

Qing-Yuan Liu ◽

Yong Li ◽

...

Keyword(s):

Water Quality ◽

Quality Improvement ◽

Flow Pattern ◽

Ecological Restoration ◽

Quality Data ◽

Quality Improvements ◽

Lake Dianchi ◽

Water Quality Data ◽

Water Quality Improvement ◽

Wind Driven Circulation

Due to rapid increases in socioeconomic development and the human population over the past few decades, the shallow lakes in China have suffered from eutrophication and poor water quality. The conditions in Lake Dianchi Caohai, which is in the northern part of Lake Dianchi, are considered the most serious. The ecological restoration of Lake Dianchi Caohai began in the late 1980s. Lake managers and the public have been puzzled by the lack of a significant response of the water quality to the flow pattern despite the tremendous investment in water quality improvements. Therefore, lake managers desperately need to understand the responses of pollutant behaviors to proposed management measures. In this paper, a depth-averaged two-dimensional hydrodynamic and water quality model based on hydrological data, measured lake bed elevation, and water quality data is developed to simulate the flow field and water quality of Lake Dianchi Caohai. This model was validated using water quality data from the Caohaizhongxin site in 2016, and a close agreement was found between the model results and observations. Wind-driven circulation in Lake Dianchi Caohai was observed in the model results, which revealed that the lake flow pattern was dominated by wind-driven circulation, while the inflow/outflow played only a subsidiary role during this period. The formation of the wind-driven current in Lake Dianchi Caohai could be roughly divided into three stages. The hydrodynamic processes connected with the distribution of chlorophyll a are evaluated and discussed to adequately understand the hydraulic mechanisms driving the accumulation of cyanobacteria. Moreover, we designed three scenarios after comparing all possible operation scenarios to analyze the contributions of each different operation scenario to the water quality improvements. The optimal ecological operation scenario which has the best impacts on the water quality, especially the reduction in Chla and NH3-N concentration, is proposed based on our comprehensive analysis. The water quality improvement and management suggestions proposed in this paper are based on lake flow patterns and make up for previous studies that did not consider the effects of hydraulic characteristics on water quality improvement in Lake Dianchi Caohai.

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