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在河蟹循环水养殖模式中,进行4种不同净化工艺对池塘养殖尾水净化效果的比较研究.工艺1以水生植物为主体进行净化;工艺2以水生动、植物进行多极净化;工艺3以浮萍和金鱼藻等进行净化;工艺4以微生态制剂和金鱼藻等进行净化.分别计算各净化区的污染物净化总量和单位净化面积的净化强度.结果表明,4种不同净化工艺对排入的池塘养殖尾水营养盐均有较好的吸收效果.不同的净化工艺对NH3-N、TN、TP和CODMn的去除能力表现出一定差异.工艺3对池塘养殖尾水中NH3-N、TN和TP的去除效果相对较好,对池塘养殖尾水中氮磷的净化效率相对优于其他3种净化工艺. 相似文献
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The biological cleaning agent Pondplus was dowsed each ten days at different dosage into breeding ponds for Chinese mitten crab with stocking rate at 12 000 ind./ha, to evaluate its purification effects on water environment in breeding ponds and its effects on Chinese mitten crab growth. The results showed that dousing treatment improved the water quality significantly as evaluated according to the parameters of DO, CODMn, NH4 + - N and NO2 - -N. Particularly, when the air temperature was higher than 35℃, the diurnal observation on DO values at the bottom of ponds showed that dousing at 450 g/( ha•m) gave a DO value higher than 4 mg/L all day long, which was 2 mg/L higher than that of control. The observed increase of Chinese mitten crab were 14. 9% , 27.8% , 27.8% by average weight, when dousing at 150, 300, 450 g/(ha • m) , respectively. Accordingly, the production increased by 8.5%, 11.9%, 18.6% through its promotion of Chinese mitten crab growth, and the economic efficiency were enhanced by 96.2% , 159.8% , 180.9%. 相似文献
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河鲀鱼肉质鲜嫩、腴美,历誉“鱼中之王”,驰名中外,其毒素具有极高的医疗价值,是有着很大开发潜力的名贵鱼类.近年长江下游地区,开发“河鲀热”迅猛发展,对其水泥池与土池养殖已取得成功和发展,但对在天然湖泊中网箱养殖尚未见报道.湖泊大水面网箱养殖具有水域广阔,水体流动,管理简便,成本低廉,集约化生产程度高的特点和优势.为了加速河鲀鱼的开发与发展,我们取用经济价值最高的暗纹东方作实验材料,从1994-1996年在吴县市漕湖水产养殖场进行了河鲀鱼网箱培育试验研究,获得成功.现将其培育技术总结如下. 相似文献
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本实验比较了褶纹冠蚌、三角帆蚌与河蚬等3种淡水贝类24h内对水族箱中藻类的消除量、消除率及0~4h对藻类的消除效率(Ki)。结果表明:褶纹冠蚌、三角帆蚌与河蚬第24h对藻类的消除率分别达到(74.3±2.9)%、(75.6±2.1)%、(88.4±3.1)%,3种淡水贝类对藻类的消除效果显著;t检验表明,24h内河蚬对藻类的消除率、消除量显著大于褶纹冠蚌和三角帆蚌(P<0.05);河蚬实验组0~4h消除效率(Ki)显著大于褶纹冠蚌和三角帆蚌(P<0.05);三角帆蚌对藻类的消除量随着贝类密度的增加显著增加,河蚬、褶纹冠蚌对藻类的消除效果受密度制约,12h后河蚬20g/L实验组对藻类的消除量最大,褶纹冠蚌40g/L实验组对藻类的消除量最大。 相似文献