Lutein enrichment of the rotifer Brachionus sp. using freeze‐dried Muriellopsis sp. cells

Rotifers, used in aquaculture as feed for early larval stages, are poor in carotenoids compared with copepods, the natural most common prey item of marine fish larvae. A minimal sufficient level of carotenoids in fish larvae may be essential for a correct development. The freshwater microalga Muriellopsis sp. has been identified as a potential source of the carotenoid lutein with possible application in aquaculture. Lutein is a potent antioxidant, with potentially beneficial effects as a carotenoid for fish larvae. This study describes the lutein enrichment of the rotifer Brachionus sp. when incubated with homogeneously dispersed suspensions of freeze‐dried, lutein‐rich Muriellopsis sp. in seawater. A short enrichment time (2 or 2.5 h) resulted in a higher lutein content of the rotifers than a long enrichment time (13.5 or 24 h). Although the concentration of lutein in enriched rotifers, 0.06–0.16 mg (g dry weight)^?1 was low compared with its content in Muriellopsis sp. [about 3 mg (g dry weight)^?1], it was in the range reported for natural copepod populations. Therefore, we conclude that freeze‐dried biomass of Muriellopsis sp. can be used to enrich rotifers with lutein, providing an adequate level of this carotenoid for marine fish larvae.     

Confidentiality over fishing effort data threatens science and management progress

Understanding the effects of fishing fleets on both target and non‐target species and managing these effects are essential to achieve Good Environmental Status (GES) for marine ecosystems. The use of high resolution fishing effort data in environmental studies has allowed significant scientific progress with respect to the environmental impacts of real fishing fleets and provided a more realistic perspective on the wider ecological consequences of fishing disturbance. A new EU council regulation and its interpretation, aimed at protecting the confidentiality rights of individual fishers, are currently hampering scientific access to this high‐resolution effort data and thus are endangering the provision of management advice based on best available knowledge. This study argues that the withholding of this information will seriously undermine the quality and accuracy of scientific output and ultimately damage fishers' livelihoods through poorly advised management. Furthermore, the council regulation runs contrary to the EU's initiative for greater transparency and its commitment to implement an ecosystem approach to fisheries management and the preservation of ecosystem services. The interpretation of the new EU council regulation by local administrations can thus only be viewed as a significant step back from these aims. Ultimately, while trying to protect fishers' rights it may work to their disadvantage and that of society.     

铜陵市老洲乡蔬菜基地重金属污染现状评价

以安徽省自然土壤背景值为参数,以国家土壤环境质量二级评价标准为依据,结合单污染指数和综合污染指数的计算,对铜陵市老洲乡蔬菜基地土壤重金属污染现状进行了评价。结果表明,土壤中5种重金属的平均含量均低于国家土壤重金属污染物二级标准,Hg、As和Cu的平均含量超过安徽省自然土壤背景值;但单项污染指标均未超过1．0,综合污染指数均在0．7以下,属于安全范围。     

我国生态风险评价研究

我国的生态风险评价研究起步较晚,理论技术和应用研究薄弱,而且缺乏生态风险管理。本文首先对生态风险评价的基本概念、内涵、通用理论框架做了介绍,然后在此基础上,通过综合分析一些在水环境和自然灾害生态风险评价、重金属沉积物生态风险评价、区域生态风险评价、农田系统与转基因作物、生物安全以及项目工程等方面的实例,对我国近年来生态风险评价的现状和存在问题进行了讨论,并对今后的研究方向做了一些展望。     

大豆疫霉卵孢子微量、快速检测方法的建立

采用套筛富集人工接种于土壤中的大豆疫霉卵孢子。结果表明,当接种量为104、103、102、101、100时,富集百分率分别为45.9%、39.6%、11.8%、1.7%、5.6%。采用玻片压碎法提取微量卵孢子中DNA后,采用PCR技术快速进行检测的结果表明,提取10,5,1个卵孢子中DNA进行PCR扩增成功率分别为83.3%、33.3%、0。提取10个卵孢子中DNA进行PCR扩增时,2个处理出现非特异性PCR产物。内切酶MspI能将特异性PCR产物消化为204bp和124bp两个片段;内切酶RsaI能将特异性PCR产物消化为242bp和86bp两个片段。     

A cost‐effective model for preliminary site evaluation for the reintroduction of a threatened quillwort

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