Distribution of bacteria involved in nitrogen and sulphur cycles in shrimp culture systems of Wes.pdfVIP

下载本文档

3
0
约3.76万字
约 14页
2017-04-11 发布于江苏
举报
版权申诉

Distribution of bacteria involved in nitrogen and sulphur cycles in shrimp culture systems of Wes.pdf

1、有哪些信誉好的足球投注网站（book118）网站文档一经付费（服务费），不意味着购买了该文档的版权，仅供个人/单位学习、研究之用，不得用于商业用途，未经授权，严禁复制、发行、汇编、翻译或者网络传播等，侵权必究。。
2、本站所有内容均由合作方或网友上传，本站不对文档的完整性、权威性及其观点立场正确性做任何保证或承诺！文档内容仅供研究参考，付费前请自行鉴别。如您付费，意味着您自己接受本站规则且自行承担风险，本站不退款、不进行额外附加服务；查看《如何避免下载的几个坑》。如果您已付费下载过本站文档，您可以点击这里二次下载。
3、如文档侵犯商业秘密、侵犯著作权、侵犯人身权等，请点击“版权申诉”（推荐），也可以打举报电话：400-050-0827(电话支持时间：9:00-18:30)。
4、该文档为VIP文档，如果想要下载，成为VIP会员后，下载免费。
5、成为VIP后，下载本文档将扣除1次下载权益。下载后，不支持退款、换文档。如有疑问请联系我们。
6、成为VIP后，您将拥有八大权益，权益包括：VIP文档下载权益、阅读免打扰、文档格式转换、高级专利检索、专属身份标志、高级客服、多端互通、版权登记。
7、VIP文档为合作方或网友上传，每下载1次，网站将根据用户上传文档的质量评分、类型等，对文档贡献者给予高额补贴、流量扶持。如果你也想贡献VIP文档。上传文档

Distribution of bacteria involved in nitrogen and sulphur cycles in shrimp culture systems of Wes

Aquaculture 239 (2004) 275–288 /locate/aqua-onlineDistribution of bacteria involved in nitrogen and sulphur cycles in shrimp culture systems of West Bengal, India T. Jawahar Abraham*, Shubhadeep Ghosh, T.S. Nagesh, Debasis Sasmal Department of Fishery Pathology and Microbiology, Faculty of Fishery Sciences, West Bengal University of Animal and Fishery Sciences, Mohanpur, Nadia-741235, West Bengal, India Received 26 January 2004; received in revised form 10 June 2004; accepted 14 June 2004 Abstract The bacteria involved in nitrogen and sulphur cycles and physicochemical characteristics of water and sediment in traditional, modified extensive and semi-intensive shrimp culture systems of West Bengal, India were monitored. The physicochemical parameters, except salinity and sediment pH, were observed to be well within the optimum levels recommended for shrimp culture. The levels of ammonia (NH3; PV0.05) and nitrite (NO2 ; Pb0.03) differed significantly among systems. The mean heterotroph counts were always close to or above 106/ml pond water and 106/g sediment. The counts of total heterotrophs and nitrate reducing bacteria (NRB) of the pond water of different culture systems differed significantly (Pb0.01). While the counts of nitrite oxidizing bacteria (NOB; Pb0.001), nitrate reducing bacteria (Pb0.01) and sulphate reducing bacteria (SRB; Pb0.03) in pond sediment of the three culture systems differed significantly. The mean counts of ammonia oxidizers increased with days of culture (DOC) in traditional and modified extensive systems, but they remained constant in semi-intensive pond sediment. The mean counts of nitrite oxidizers were generally high in water and sediment samples of modified extensive system. The mean sulphur oxidizing bacterial counts of pond water were higher in semi-intensive and modified extensive systems, which generally decreased with increasing DOC. The sulphate reducing bacterial counts of sediment increased with DOC in modified extensive and se