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湖区河蟹群体通常由三个年龄组组成。造成河蟹资源量年变化有三方面原因。影响其资源盛衰主要有十大因素。秋冬季河蟹捕获量中Ⅱ秋龄占多数达61.68％。蟹苗放流后的回捕指数400～800,回捕率2～4％。放流效果由湖区饵料基础、放流密度、栖息环境、水位变动、潮泊性状和人为伤害等条件决定。
Lake crab population usually consists of three age groups. There are three reasons for the annual change of crab resources. Affect the ups and downs of its resources there are ten major factors. Autumn and winter crab catches in the majority of Ⅱ autumn accounted for 61.68%. Crab release back to the catching index 400 ~ 800, the recovery rate of 2 to 4%. The discharge effect is determined by the basic conditions of the bait, discharge density, habitat, water level changes, tidal characteristics and man-made damage in the lake area.