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随着精养池塘富营养化的日趋严重,微囊藻水华也大量出现,微囊藻水华形成后又向水体排放含N、P、C物质和一类单环七肽的生物毒素,加剧水质恶化,给鱼类生长以及渔业生产的发展带来很大的影响。我们从微囊藻水华形成的环境因子入手,应用药物清杀,给全水泥衬砌池塘回填粘土,在池塘底泥中种植小麦,在微囊藻水华大量出现时增放红草鲫鱼等综合方法,成功地抑制了微囊藻水华的形成和发展。 相似文献
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2015年5月6日-6月1日,对陕西临潼地区大宗鱼类苗种培育池塘水体中的浮游植物进行调查分析。结果表明:培育池塘中共鉴定出浮游植物5门32种。其中绿藻门有21种,占总种类数的65.62%;硅藻门有4种,占总种类数的12.50%;蓝藻门有4种,占总种类数的12.50%;隐藻门有2种,占总种类数的6.25%;甲藻门有1种,占总种类数的3.13%。培育早期浮游植物种类数16种,密度为1.262×107ind./L,培育后期浮游植物种类数19种,密度为1.125×108ind./L,浮游植物平均密度为5.401×107 ind./L。浮游植物数量变化总体表现为前期低后期高的特征。 相似文献
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为了提高陕西地区长丰鲢苗种的培育成活率,于2015年5月21日~6月17日,对渭南合阳地区长丰鲢夏花苗种培育池塘水环境进行了监测。结果表明:培育期间池水温度随着时间推移总体呈现上升趋势,变化范围23.7~29.4℃,均值为25.9℃;溶解氧的变化呈现出先降低后升高再降低的趋势,范围为5.82~12.01mg/L,均值为8.77 mg/L;透明度呈现先增大后减小的变化趋势,变化范围19.5~40.5cm,均值为33.4cm;pH值的变化呈现先降低后升高的趋势,范围为8.35~9.45,均值为8.93;亚硝酸盐含量呈上升趋势,变化范围0.074~0.189mg/L,均值为0.108mg/L;氨氮含量呈现逐渐升高的趋势,变化范围0.082~1.159mg/L,均值为0.517mg/L。分析表明,随着时间的推移,池塘水环境指标受气温和追肥的影响呈现的变化趋势存在差别,各项水质指标在不同采样时间的监测值存在差异。 相似文献
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黄河干流中上游水生生物资源调查研究 总被引:19,自引:1,他引:18
In order to protect scientifically the fishery resources and eco-environment of Yellow River , nine investigatioins on hydrobios in the middle and upper reaches of main Yellow River had been carried out since 2002 according to The Standard for the investigation of inland fishery resources. The investigations showed the present status of the fishery resources in these reaches are as follows :87species (genera)and 8 phylum of phytoplankton,42 species and 6 phylum of zooplankton, 14 species(genera) of banthic organism , 5 species of hydroplant, 38 species of fish. A comparative analysis,With the results of "the Yellow River Fishery Resources Survey in 1982",shows that the general trend of the plankton is that the average biomass is getting apparently decreased, the aboriginal fishes are endangered intensifically, and there must be some problem of aquatic biological invasion in these reaches. A granual miniaturization of fishes in main Yellow River has been noticed. The authors proposed to carry out investigation and researches on hydrobios resources in main Yellow River , and develop plans to protect the fishery resources in yellow River, which will be an important basis for rehabilitation of the Yellow River waters and it's ecological environment, for the maintenance of biological diversity of Yellow River's waters. And this work will be of great significance for people's life and sustainable development of economics in Yellow River basin. 相似文献