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在底栖动物中,不少种类是优良的饵料生物,还有一部分是高级装饰品与药品的原材料,其数量和分布是合理放养底栖性鱼类和资源综合利用的依据之一。从1982年到1985年,我们对柳叶湖的软体动物、水蚯蚓和摇蚊幼虫的种群、现存量、分布规律以及季节变化作了调查研究,并对可供鱼产量作了估算。一、工作方法 1、设点。软体动物的采样是同水生植物的调查一同进行的,在全湖共设置了16个断面71个测点。断面是根据水面形状均匀分布,断面上各测点与其中心点对称布局。
Among zoobenthos, many species are excellent bait organisms, and some are raw materials of high-grade decorations and medicines. The quantity and distribution of zoobenthos are the basis for rational stocking of the benthic fish and resources. From 1982 to 1985, we surveyed the population, existing stock, distribution and seasons of molluscs, water earthworms and chironomid larvae in Willow Lake and estimated available fish yields. First, the working methods 1, set point. Sampling of molluscs was conducted in conjunction with a survey of aquatic plants, with 71 measuring points set at 16 sections across the lake. The cross section is evenly distributed according to the shape of the water surface. Each measurement point on the cross section is symmetrically arranged with its center.