RELATIONSHIP BETWEEN CHANGE IN ZOOPLANKTON COMMUNITY AND WATER QUALITY OF JINGMI CANAL AND BEIJING SEWAGE STREAM
Xu Muqi (Institute of Zoology,Chinese Academy of Seiences,Beijing 100080)
Zooplankton investigation and water quality evaluation were carried out in Jingmi Canal and Beijing Sewage Stream in various seasons during 1982 -1984. The water quality of 18 sampling stations were categorized into 5 levels according to the changes in community structure and diversity index. In the upper stations of Jingmi Canal, the fundamental characteristics of the water bodies were clear species, low quantity and high diversity index value, so the water quality in these sections may be classified as level 1-2, In the lower reaches of the canal where the bodies of water were heavily polluted by wastewater from urban districts, the diversity index values evidently declined with the decrease in species number and the increase in quantity of tolerance species, so the water quality may be of level 4-5. The water quality in the lower waters of Beijing Sewage Stream showed obvious improvement and they belong in level 3 due to self-purification.