大水面增养殖河蟹成本低、效益高,并且由于北方地区昼夜温差大,日照长,生长期长和水质的原因,同样品种北方养殖的河蟹口感要好于南方,因此特别受市场欢迎。几年来,河蟹增养殖发展十分迅速,但由于各种原因却出现效益下滑,甚至出现了亏损现象。1存在问题1.1管理粗放,技术水平低由 Because of the large temperature difference between day and night, long sunshine period, long growing period and water quality in the northern area, the crab taste better than that in the south for the same breed, so it is particularly welcomed by the market. Over the past few years, the culture of crab by the rapid development of the breeding, but due to various reasons, there have been a decline in efficiency, or even a loss phenomenon. 1 problems 1.1 extensive management, low technical level