Project Scope and Relationship to China's Agenda 21

This project is intended to restore the ecological balance of the Dianchi Basin, Yunnan Province. It emphasizes non-point source pollution control techniques and is characterized by a series of model engineering measures. The project is based on the sustainable development and capacity building objectives of programme area 14E of China's Agenda 21 and contributes to a number of related fields including water environmental protection, conservation of land, water and biodiversity resources, leading to sustainable development of the Dianchi Basin.

1. Background

Dianchi Lake is a famous fresh water lake located near Kunming City on the Yungui Plateau of Southwest China, and is one of the key lake protection sites in China.

Agricultural and industrial output in the Dianchi lake basin account respectively for 79.8% and 82.2% of Kunming City's total. It is not only the biggest drinking water source for the city, but serves many other functions, including water supply for agriculture and climate regulation. In addition, it plays a very important role in maintaining the equilibrium of the regional ecosystem. In fact, Dianchi Lake is so important to the local economy that without it, Kunming could not have developed to its present economic level.

The area of Dianchi Lake is shrinking annually and water pollution problems in the lake are increasingly serious. In summer and autumn, 84% of the lake surface is covered with algae, which affects the operation of the No.3 Municipal Water Plant, which sometimes has to stop production. The Fifth Water Plant on the east shore of Dianchi Lake also is unable to maintain normal operation due to algal blooms. Reduced supplies and poor quality of tap water has evoked very strong public response in the surrounding urban areas.

The Waihai Lake section of Dianchi Lake is affected by about 0.2 billion tons of waste water runoff, containing 5,000 tons of total nitrogen and 500 tons of total phosphorus. The main task of controlling Lake Dianchi will be: control of urban point sources, and control of surface sources of the basin to restore the ecological balance of the lake. The control of point sources has been planned by the city government and some engineering measures have been implemented. However, the ecological park project is an important measure for pollution control of Dianchi Lake. Rational economic utilization of the lake is to be integrated with protection through construction engineering, serving the dual purpose of ecological protection and tourism and recreation.

Studies have been done on comprehensive prevention and control techniques for eutrophication and maximum nitrogen and phosphorus levels for typical lakes, including:

• Studies on measurement techniques for non-point sources
• Investigation and analysis of the inflow of pollutants from storm runoff in the year 1988
• Variations in pollution loading under different types of land use
• Analysis of runoff characteristics
• Nutrients sources in the storm runoff

In the national key research projects of the current Eighth Five-Year Plan period, the studies related to this project are:

• Studies on techniques for model engineering of the protection zone on the lake shore
• Techniques for controlling agricultural pollution runoff
• Techniques for pre-reservoir engineering
• Studies on ecological recovery engineering of small basins

Advisors from UNESCO have been invited to conduct training on the techniques of ecological lake shore engineering and eutrophication prevention.

2. Objectives

The overall objective of this project is to suggest management measures and suitable technical and engineering measures for the control of eutrophication and for the water reclamation in Dianchi Lake and to construct the related demonstration project.

3. Activities

• 3.1 Control non-point pollution sources in Dianchi Lake.
  • Investigate the types and characteristics of land resources, the present situation of land exploitation and the land use patterns of the Dianchi Lake Basin.
  • Establish an engineering programme for water and soil erosion control and vegetation recovery in the areas undergoing ecological disruption, including establishment of water and soil erosion models, a study on quantitative relationship between water and soil erosion and vegetation coverage, water and soil conservation and afforestation.
  • Develop techniques for vegetation recovery in waste land and mines, through studies on physical-chemical properties and evaluation of waste land, the effect of waste land on plant growth, screening of plant species suitable for waste land, techniques of plant cultivation and management and model engineering for vegetation recovery of large areas.
  • Construct ecological agricultural engineering in agricultural areas, including the establishment of patterns for development of ecological agriculture, the development of techniques for appropriate use of agricultural fertilizers and use of ecologically benign agricultural techniques and the construction of model engineering for ecological agriculture.

• 3.2 Develop techniques for purification of surface water in the lake, discharges by hydroponic techniques and model engineering
  • Develop techniques for land treatment system
  • Study the re-utilization of water discharges from hydroponic systems
  • Construct a demonstration zone for use of sewage for hydroponic systems

• 3.3 Design an ecological park around Dianchi Lake and construct model areas.
  • Investigate land use and resources around the lake:
    • Land use and lake shore zoning programme
    • Investigation of the environmental function of lake shore zoning programme
    • Investigation of pollution sources and discharge rules in the lake shore zone
    • pollution prevention for various lake shore zones

  • Design an ecological park around the lake:
    • Design of an ecological protection belt
    • Scenic areas programme
    • Design of ecological protection zone
    • Road programme

  • Construct ecological park demonstration zones around the lake:
    • Construction of an ecological protection belt
    • Model construction of scenic areas (minority villages, Dianchi Gallery of Science and Technology, etc.)
    • Construction of wetland protection zone around the lake
    • Construction of model zone for public parks around the lake
    • Construction of model zone for comprehensive exploitation

• 3.4 Build capacities for the implementation of this project.
  • Train 3-4 persons as backbone technical staff for planning and implementing sewage cultivation techniques and environmental management of the lake basin.
  • Establish automatic monitoring and control systems for lakes in China.
  • Establish national satellite information system network for lake environments

  The duration of this activity will be four years.

  The project will be implemented by the National Environmental Protection Agency and the local government.

5. Benefits

This project is intended to restore water quality in Dianchi Lake to the 1980s level and combat pollution of the lake environment. At the same time, technical personnel will be trained. After project implementation, it is expected that the considerable economic losses due to environmental pollution and eutrophication can be reduced. Moreover, the project will benefit human health and social stability. Its economic, social and environmental benefits are multi-fold, and it will play an important role in the sustainable economic development of lake basins in China.