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一、为什么要研究水蛭的人工养殖 近１２年来水蛭市场价格出现了两次巨大的波浪形上升趋势。１９８８～１９９０年３年中水蛭价格从潜伏型谷底每公斤１０－２５元暴涨至每公斤２０元上下的波峰顶价位。修正波回调到１９９３年前后，价格又回落到每公斤６０－７０元的波谷底。但
First, why to study the artificial cultivation of leeches Leech market prices in the past 12 years there have been two huge wave-shaped upward trend. From 1988 to 1990, the price of leeches plunged from 10-25 yuan per kilogram of lurking valley to 20 yuan per kilogram of peak top-down price. Correction wave callback to around 1993, the price dropped to 60-70 yuan per kilogram at the bottom of the trough. but