渍涝洼地鱼塘中浮游动物的变化

1987—1989年对山东省禹城渍涝洼地新开鱼塘水体中浮游动物进行了调查。1987、1988、1989年成鱼养殖期间共检出浮游动物种类分别为29、34、52种,平均数量为11911、39366.1、77889.2个/L,平均生物量为5.145、5.7675、9.6285mg/L。1988、1989年,鱼塘水体中浮游动物的数量高峰在7月。新开鱼塘养鱼前,只检出5种。数量为600个/L,生物量为0.0585mg/L。养鱼后三年来,鱼塘水体中浮游动物种类、数量及生物量的逐年增加,表明了新开鱼塘富营养化的演变程度。鱼塘施肥前后,水体中原生动物与轮虫的数量均有明显变化,其中原生动物变化更为明显。

CHANGES OF THE ZOOPLANKTON IN THE FISH POND OF LOW-LYING SALINE-ALKALI WETLAND

Zooplankton in a newly-dug fish pond in the saline-alkali wetland in Yucheng County of Shandong Province from 1987-1989 was studied. During the 3 years, investigation the species of zooplankton were ascendant, the amount and the biomass were also incremental. In 1987, 1988 and 1989, the species of zooplankton were as follows; 29 species, 33 species and 52 species separately, the average amount of zooplankton: 11911 ind/L, 39366.1 ind/L and 77889.2 ind/L, and the average biomass: 5, 145mg/L,5.7675mg/L and 9.6285mg/L. From 1988 to 1989, the peak amount of the zooplankton appeared in July. The successive increase in the species, the total amount and the biomass of the zooplankton during the three years showed the variation of eutrophication in the newly-dug fish pond. The amounts of protozoa had an obvious variation before and after fertilizing the fish pond. The increasing tendency of the amounts of zooplankton led to the conclusion that phytoplankton had equated the changes of the bacteria, showing that the protozoa were dependent on the phytoplankton but independent on the bacteria in the food chains.