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在养蟹池中,免不了出现一些“洞蟹”。由于河蟹长期栖息洞中很少出来活动和觅食,因而生长缓慢。“洞蟹”越多,产量自然锐减。 “洞蟹”不是天生如此,而是后期环境形成的。主要原因有四个,一是池水大小变动过快,河蟹来不及迁居,只好打洞于“潮间带”,形成洞穴习性”二是池水水质严重污染或溶氧量低,河蟹不适,于是爬岸打洞穴居;三是水中没有水生植物和漂浮性附着物,蟹缺乏呼吸新鲜空气和觅食歇息的环境条件,只好离开水面,穴居洞中;四是投饵不均,有些河蟹长期处于饥饿状态,只好摄取洞穴附近泥中腐殖质来维护生命,时间一长,形成穴居习性。
In the crab pool, inevitably there are some “cave crabs.” The crabs grow slowly because they rarely come out of activities and foraging for long-term habitat. The more “crabs”, the sharp drop in output. “Cave crab” is not born like this, but the formation of the late environment. There are four main reasons, first, the size of the water changes too fast, crabs too late to move, had to hole in the “intertidal zone, the formation of cave habits” Second, the water quality of the serious pollution or dissolved oxygen is low, crab discomfort, Burrowing burrows; Third, there is no aquatic plants and floating attachments in the water, crabs lack of fresh air and feeding habit of respite environmental conditions, had to leave the surface cave cave; Fourth, uneven feeding, and some crabs long-term starvation , Had to ingest the humus near the cave to maintain life in the mud, over time, the formation of cave habits.