Remediation of Polluted River Water by Biological, Chemical, Ecological and Engineering Processes

Selection of appropriate river water treatment methods is important for the restoration of river ecosystems. An in-depth review of different river water treatment technologies has been carried out in this study. Among the physical-engineering processes, aeration is an effective, sustainable and popular technique which increases microbial activity and degrades organic pollutants. Other engineering techniques (water diversion, mechanical algae removal, hydraulic structures and dredging) are effective as well, but they are cost intensive and detrimental to river ecosystems. Riverbank filtration is a natural, slow and self-sustainable process which does not pose any adverse effects. Chemical treatments are criticised for their short-term solution, high cost and potential for secondary pollution. Ecological engineering-based techniques are preferable due to their high economic, environmental and ecological benefits, their ease of maintenance and the fact that they are free from secondary pollution. Constructed wetlands, microbial dosing, ecological floating beds and biofilms technologies are the most widely applicable ecological techniques, although some variabilities are observed in their performances. Constructed wetlands perform well under low hydraulic and pollutant loads. Sequential constructed wetland floating bed systems can overcome this limitation. Ecological floating beds are highly recommended for their low cost, high effectiveness and optimum plant growth facilities

Assessment of Long-Term Watershed Management on Reservoir Phosphorus Concentrations and Export Fluxes.

Source water nutrient management to prevent eutrophication requires critical strategies to reduce watershed phosphorus (P) loadings. Shanxi Drinking-Water Source Area (SDWSA) in eastern China experienced severe water quality deterioration before 2010, but showed considerable improvement following application of several watershed management actions to reduce P. This paper assessed the changes in total phosphorus (TP) concentrations and fluxes at the SDWSA outlet relative to watershed anthropogenic P sources during 2005⁻2016. Overall anthropogenic P inputs decreased by 21.5% over the study period. Domestic sewage, livestock, and fertilizer accounted for (mean ± SD) 18.4 ± 0.6%, 30.1 ± 1.9%, and 51.5 ± 1.5% of total anthropogenic P inputs during 2005⁻2010, compared to 24.3 ± 2.7%, 8.8 ± 10.7%, and 66.9 ± 8.0% for the 2011⁻2016 period, respectively. Annual average TP concentrations in SDWSA decreased from 0.041 ± 0.019 mg/L in 2009 to 0.025 ± 0.013 mg/L in 2016, a total decrease of 38.2%. Annual P flux exported from SDWSA decreased from 0.46 ± 0.04 kg P/(ha·a) in 2010 to 0.25 ± 0.02 kg P/(ha·a) in 2016, a decrease of 44.9%. The success in reducing TP concentrations was mainly due to the development of domestic sewage/refuse collection/treatment and improved livestock management. These P management practices have prevented harmful algal blooms, providing for safe drinking water

The study of agricultural non-point source pollution control policy system

As the agricultural non-point source pollution(ANPSP) has become the most significant threat for water environmental deterioration and lake eutrophication in China, more and more scientists and technologists are focusing on the control countermeasure and pollution mechanism of agricultural non-point source pollution. The unreasonable rural production structure and limited scientific management measures are the main reasons for acute ANSPS problems in China. At present, the problem for pollution control is a lack of specific regulations, which affects the government\u27s management efficiency. According to these characteristics and problems, this paper puts forward some corresponding policies. The status of the agricultural non-point source pollution of China is analyzed, and ANSPS prevention and control model is provided based on governance policy, environmental legislation, technical system and subsidy policy. At last, the case analysis of Qiandao Lake is given, and an economic policy is adopted based on its situation

Integrated Management of Industrial and Municipal Wastewater in China. - Demonstration Project in Jiaxing, Zhejiang Province

Årsliste 2000The city of Jiaxing in Zhejiang Province is a medium-size, rapidly expanding Chinese city located in a flat landscape with numerous canals. These are used for navigation, fishing, aquaculture and as drinking and industrial water source, but also as recipients for domestic and industrial wastewater and runoff from agriculture, paved roads and solid waste landfills in the area. The canals are severely polluted. NIVA has been assisting Jiaxing Environmental Protection Bureau (JEPB) in finding solutions to the local wastewater problems. The industry in the area discharges substantial quantities of potentially toxic wastewater to the sewer systems. There are, however, good possibilities for cleaner production routines in various factories. Several measures facilitate the transport of sewage to the nearby Hangzhou Bay, and sewage treatment processes before final disposal have been identified. The project has identified current and future wastewater production and recipient status. Based on pilot-plant operation and computer models a complete system for sewage collection and treatment has been suggested. This is based on transport of untreated sewage to Hanfzhou Bay where the construction of a sewage treatment plant is planned. The treatment methodology is based on a flexible chemically enhanced primary treatment (CEPT), followed by a biological step at a later stage. The project findings put emphasis on knowledge transfer and strengthening of JEPB resources to find solutions to the water-related problems in the city. In addition a detailed abatement plan should be developed, taking existing water quality, user interests and future water quality objectives into account.Direktoratet for Utviklingshjelp (NORAD

Spatial assessment and management of regional ecosystem services in the Yangtze River Delta Region

The Yangtze River Delta (YRD) metropolitan region is one of the most rapidly urbanized regions in China and has experienced a remarkable period of population growth (at an annual growth rate of 3.0%), and urbanization (at an annual growth rate of 9.2%). Rapid urbanization has dramatically changed land use/land cover patterns and ecosystems in the region, causing widespread environmental problems such as habitat fragmentation, aggravation of environmental pollution, decline in biodiversity and ecosystem degredation. These problems have restricted the sustainable development of socio-economic system of the Yangtze River Delta Region. Facing the challenges, the Yangtze River Delta Region is carrying out the practice of regional integration planning and cooperation in environmental governance, which urgently needs the guidance of relevant theories and methods. Some of the key environmental policy pilots have been carried on in this region, such as the Ecological Red Line Policy (Bai et al, 2016; Lü et al, 2013). This policy has one of the main objectives of protecting important eco-function areas i.e. ecosystem service hot spots, to deliver services such as water storage, clean drinking water, and carbon sequestration, and to maintain ecological safety to support economic and social development, which an important policy orientation of ecosystem services approach.Ecosystem services are the contributions of ecosystem structure and function to human well-being, connecting natural and socio-economic systems. The ecosystem services approach is considered to be one of the important decision support tools for guiding and formulating environmental policies. Based on the theories and methods of ecosystem services, combined with local expert knowledge, remote sensing and GIS technologies, this dissertation aims is mainly to develop a comprehensive framework of ecosystem services assessment and decision support for rapid urbanization regions.Based on this framework, the spatial characteristics, supply-demand relationship and flow direction of ecosystem services in the Yangtze River Delta Region are analysed and evaluated. Main results of this thesis are as follows:(1) According to the characteristics of the regional ecosystems of the Yangtze River Delta Region, combined with local expert knowledge, the Burkhard’s scoring and assessment method of ecosystem services was improved, and the score matrix between twelve ecosystem types and twenty-three ecosystem services in the Yangtze River Delta Region was established.(2) Based on DPSIR model, the characteristics of the social-ecological complex ecosystem and change of ecosystem services in the Yangtze River Delta Region were analysed. The main ecological and environmental problems were identified. Causes and main driving forces of decline in ecosystem services were revealed in the region.(3) Based on ARCGIS platform, the status quo of ecosystem services in the Yangtze River Delta region was analysed and evaluated. The spatial differentiation characteristics and main impact factors of ecosystem services in the Yangtze River Delta region were clarified. The hot spots of total ecosystem services were aggregated in the southwest areas, while the cold spots were distributed in the middle and northeast areas of the region. The hot spots of supporting services and regulating services aggregately distributed in the southwest mountainous areas while hot spots of provisioning services mainly in the northeast plain, and high value of cultural services widespread in the waterbodies and southwest mountainous areas. The spatial heterogeneity is determined by biophysical features and land use types. Based on the assessment, six major ecosystem services functional zones were divided: (I) South Ecological Integrity Conservation Zone, (II) Southwest Mountainous and Hilly Forest Ecological Zone, (III) Northeast Plain Agriculture Ecological Zone, (IV) Middle Aquatic Ecological Conservation Zone, (V) Eastern Coastal Estuaries Ecological Zone, and (VI) Urban Development Area., and the corresponding management strategies on the basis of environmental problems and ecosystem services characteristics in each of the functional zones were put forward.(4) Using regional spatial data in net primary productivity, the quality levels of forest and cropland were graded and the previous scores of ecosystem services in forest and cropland were calibrated. Then, the hot spots and clustering patches of forest and farmland ecosystem services were identified by ARCGIS tools. Finally, the forest ecosystem conservation areas (red line) and cropland ecosystem conservation areas (red line) in the Yangtze River Delta region were delineated.(5) Based on the improved Burkhard’s supply-demand budget of ecosystem services method, the budgets of three regulating services (erosion regulating service, flood regulating service and water purification regulating service) of the sixteen core cities in the region were established, and the characteristics of surplus and deficit of three services of the cities in the region were analysed. Combing the budget with analysis of flow direction of ecosystem services, the potential provisioning cities and the benefiting cities of ecosystem services are identified. On the basis of the results, the potential model of regional inter-city environmental cooperation is proposed.This dissertation not only improves the methods of ecosystem service assessment and decision support in rapidly urbanized regions, but also makes contributions to the guidance in delineation of ecological red line, regional environmental cooperation and sustainable development in the Yangtze River Delta Region

Studies on Water Management Issues

This book shares knowledge gained through water management related research. It describes a broad range of approaches and technologies, of which have been developed and used by researchers for managing water resource problems. This multidisciplinary book covers water management issues under surface water management, groundwater management, water quality management, and water resource planning management subtopics. The main objective of this book is to enable a better understanding of these perspectives relating to water management practices. This book is expected to be useful to researchers, policy-makers, and non-governmental organizations working on water related projects in countries worldwide

Phosphorus recovery: a need for an integrated approach

Increasing cost of phosphate fertilizer, a scarcity of high quality phosphate rock (PR)and increasing surface water pollution are driving aneed to accelerate the recovery and re-use ofphosphorus (P) from various waste sectors. Options to recover P occur all along the open P cycle from mining to households to oceans. However, P recovery as a regional and global strategy towards P sustainability and future food, bio energy and water security is in its infancy because of a number of technological, socio-economic and institutional constraints. There is no single solution and resolving these constraints requires concerted collaboration betweenrelevant stakeholders and an integrated approach combiningsuccessful business models withsocio-economic and institutional change. We suggest that an operational framework is developed for fast tracking cost-effective recovery options