耳萝卜螺对菹草的牧食研究

Radix auricularia on the Potamogeton crispus Grazing Research

摘要: 水生态系统中存在螺–草互利现象。然而，植食性螺类与水生植物之间是否存在这种互利关系目前尚无定论。耳萝卜螺是水体中常见的淡水螺类，常常匍匐岸边或附着在水生植物茎及叶片上。菹草是水体中常见的沉水植物，常常大量繁殖引起水体富营养化。为此我在实验室可控条件下，研究了耳萝卜螺牧食对菹草生长的影响。结果表明：耳萝卜螺的牧食对菹草生长有显著影响，牧食损害使菹草的相对生长率、块茎数量及重量下降；耳萝卜螺对菹草的牧食率随耳萝卜螺规格的变化而改变，耳萝卜螺规格越小对菹草的牧食率越高。

Abstract: There is a mutual beneficial phenomenon between snails and grass in the aquatic ecosystem. However, we have not reached the conclusion on the existence of mutual relationship between plant feeding snails and hydrophyte. Radix auricularia is common freshwater snails in the water, which prostrates on the shore or attaches on the aquatic plant stems and leaves. Radix auricularia, which is a common water submerged plant, blooms frequently and causes eutrophication. This is the reason why under the controlled conditions, I did the research on the Radix auricularia which has grazing effects on the growth of Potamogeton crispus. The result shows that: Radix auricularia has grazing effect on the growth of Potamogeton crispus; grazing of Radix auricularia has quite effect on the growth Potamogeton crispus; the grazing rate of Radix auricularia to Potamogeton crispus will be altered by the change of the specifications of Radix auricularia, as well as the weight of tubers. And the smaller in the specifications of Radix auricularia, the higher in the grazing rate of Potamogeton crispus.