Joint Research Project
Sustainable Management of the Newly Created Ecosystem at the Three Gorges Dam (YANGTZE-PROJECT)

Research Group HYDRO
Pollutants / Water / Sediment – Impacts of Transformation and Transportation Processes on the Yangtze Water Quality

Sub-Project
Transformation, Bioaccumulation and Toxicity of Organic Micropollutants in the Yangtze Three Gorges Reservoir (MICROTOX)

Duration

2010 - 2013

Leader

Prof. Dr. rer. nat. Andreas Schäffer (Modules 1 + 2)
Prof. Dr. rer. nat. Henner Hollert (Module 3)

Coordination

Dipl.-Biol. Björn Scholz-Starke (Module 2, coordination)

Processing

MSc Ye Yuan (Module 1)
Dipl.-Biol. Tilman Floehr (Module 3)
Katrin Strauch (Module 2)
Dr. rer. nat. Martina Roß-Nickoll (Module 2)
Dr. rer. nat. Burkhard Schmidt (Module 1)
Dr. rer. nat. Dipl.-Ing. Richard Ottermanns (Module 2)



Figure 1: Area near the city of Xainian, which can be cultivated when temporarily fallen dry during water level fluctuations of the Three Gorges Reservoir


Figure 2: Intended sampling point in the urban area of Chongqing


The Three Gorges Dam is one of the great projects that enduringly change Chinas nature. Its Reservoir covers a total area of ca. 1085 km2 of the Yangtze river in a total length of 663 km. The creation of the reservoir caused the flooding of former urban, industrial and agricultural areas. This caused a release of substantial amounts of organic and inorganic pollutants into the reservoir. Additionally, contaminants and nutrients (e.g. nitrate, phosphate) enter the reservoir by runoff from adjacent agricultural areas as well as from sewage of industry, aquacultures and households. Periodical changes in water level cause flooding events and thereby a relocation of contaminated water, particulate matter and sediment onto agriculturally used areas along the reservoirs shore. The Three Gorges Reservoir and its surrounding area is the source of food and water for plenty of people. Based on these risks for the population and to preserve this newly created ecosystem it is of importance to develop techniques and procedures that sustainably limit the emission of contaminants into the reservoir.

The recent project is integrated into the joint research framework ‘Sustainable Management of the Newly Created Ecosystem at the Three Gorges Dam (YANGTZE-PROJECT)’ financed by the Federal Bureau of Education and Science (BMBF) as part of the research cluster ‘Pollutants / Water / Sediment – Impacts of Transformation and Transportation Processes on the Yangtze Water Quality’. The joint project is carried out in cooperation with numerous German and Chinese partners.

Aim of the presented project is to elucidate the fate (Module 1), potential of bioaccumulation (Module 2) and ecotoxicological properties of major Yangtze pollutants to indigenous organisms (Module 3). Overall objective is to develop a monitoring strategy to evaluate the degree of pollution and identify pollution hot spots in the Three Gorges Reservoir. Beyond may these findings serve as a starting point for a subsequent project on management strategies to reduce the pollution in temporary Yangtze flooding areas.

Figure 3: Fate of organic pollutants in the reservoir: 1) Biotic and abiotic degradation (e.g. photodegradation); 2) Sorption to organic and inorganic particles; 3) Distribution between water and sediment. A high nutrient level in the reservoir elevates the microbial activity. This stimulates the degradation of pollutants and the formation of biofilms on particles, which reduces the bioavailability of particle enclosed contaminants. Under anoxic conditions particles can be covered by biofilms within the sediment and pores. The fate of the pollutants can vary strongly between anoxic and oxic conditions. By sedimentation and water turbulences are the contaminants transported between surroundings offering the one or the other condition.

Principal

Federal Ministry of Education and Research (BMBF)

Cooperation partners

Germany:

• Research Center Jülich
• Karlsruhe Institute of Technology
• Water Technology Center Karlsruhe
• IWW Water Centre Mülheim
• Helmholtz Center Munich / Technical University Munich
• University of Stuttgart

China:

• Tongji University Shanghai
• University of Nanjing
• Chongquing University

Publications:

Poster presentations:

• SCHÄFFER A, HOLLERT H, ROß-NICKOLL M, SCHMIDT B, OTTERMANNS R, SCHOLZ-STARKE B, YUAN Y, FLOEHR T, STRAUCH K (2011) Transformation, Bioaccumulation and Toxicity of Organic Micropollutants in the Yangtze Three Gorges Reservoir – MICROTOX. SETAC Europe 21th Annual Meeting 15-19 May 2011, Milano, Italy