Halogenated Indole Alkaloids from Marine Invertebrates

This review discusses the isolation, structural elucidation, and biological activities of halogenated indole alkaloids obtained from marine invertebrates. Meridianins and related compounds (variolins, psammopemmins, and aplicyanins), as well as aplysinopsins and leptoclinidamines, are focused on. A compilation of the ¹³C-NMR spectral data of these selected natural indole alkaloids is also provided.     

The demise of Darwin's fishes: evidence of fishing down and illegal shark finning in the Galápagos Islands

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淡水中重金属镉的水质基准制定

通过查阅数据库,研究了重金属镉对我国淡水水生生物的毒性效应一,在借鉴美国环境保护局提出的毒性百分数排序法的基础上,结合我国的生物区系特点和实际情况,计算出了淡水中镉的最终急性值、最终慢性值和最终残留值,分别为17．400、1．036、0．123μg／L,并在此基础上,得出了淡水镉的基准值,即基准最大浓度为8．700μg／L,基准连续浓度为0．123μg／L     

Antitumor Profile of Carbon-Bridged Steroids (CBS) and Triterpenoids

This review focuses on the rare group of carbon-bridged steroids (CBS) and triterpenoids found in various natural sources such as green, yellow-green, and red algae, marine sponges, soft corals, ascidians, starfish, and other marine invertebrates. In addition, this group of rare lipids is found in amoebas, fungi, fungal endophytes, and plants. For convenience, the presented CBS and triterpenoids are divided into four groups, which include: (a) CBS and triterpenoids containing a cyclopropane group; (b) CBS and triterpenoids with cyclopropane ring in the side chain; (c) CBS and triterpenoids containing a cyclobutane group; (d) CBS and triterpenoids containing cyclopentane, cyclohexane or cycloheptane moieties. For the comparative characterization of the antitumor profile, we have added several semi- and synthetic CBS and triterpenoids, with various additional rings, to identify possible promising sources for pharmacologists and the pharmaceutical industry. About 300 CBS and triterpenoids are presented in this review, which demonstrate a wide range of biological activities, but the most pronounced antitumor profile. The review summarizes biological activities both determined experimentally and estimated using the well-known PASS software. According to the data obtained, two-thirds of CBS and triterpenoids show moderate activity levels with a confidence level of 70 to 90%; however, one third of these lipids demonstrate strong antitumor activity with a confidence level exceeding 90%. Several CBS and triterpenoids, from different lipid groups, demonstrate selective action on different types of tumor cells such as renal cancer, sarcoma, pancreatic cancer, prostate cancer, lymphocytic leukemia, myeloid leukemia, liver cancer, and genitourinary cancer with varying degrees of confidence. In addition, the review presents graphical images of the antitumor profile of both individual CBS and triterpenoids groups and individual compounds.     

关于湖北省淡水产业发展的思考

湖北省是中国淡水产品生产大省,淡水产业对湖北国民经济的发展和农民增收具有重要的现实意义。本文对2004年湖北省淡水产业的发展概况进行了深入的剖析,并与全国各主要省份,特别是内陆的安徽、江西、湖南和重庆,沿海的广东、江苏、浙江和山东等省份的淡水产业进行了比较研究,分析了湖北省存在的问题和障碍因素;最后依据产业指向性原理和关联分析理论等进行了产业发展论证,提出了培育和壮大湖北淡水产业的对策与建议。     

Cyanotoxins: bioaccumulation and effects on aquatic animals

Cyanobacteria are photosynthetic prokaryotes with wide geographic distribution that can produce secondary metabolites named cyanotoxins. These toxins can be classified into three main types according to their mechanism of action in vertebrates: hepatotoxins, dermatotoxins and neurotoxins. Many studies on the effects of cyanobacteria and their toxins over a wide range of aquatic organisms, including invertebrates and vertebrates, have reported acute effects (e.g., reduction in survivorship, feeding inhibition, paralysis), chronic effects (e.g., reduction in growth and fecundity), biochemical alterations (e.g., activity of phosphatases, GST, AChE, proteases), and behavioral alterations. Research has also focused on the potential for bioaccumulation and transferring of these toxins through the food chain. Although the herbivorous zooplankton is hypothesized as the main target of cyanotoxins, there is not unquestionable evidence of the deleterious effects of cyanobacteria and their toxins on these organisms. Also, the low toxin burden in secondary consumers points towards biodilution of microcystins in the food web as the predominant process. In this broad review we discuss important issues on bioaccumulation and the effects of cyanotoxins, with emphasis on microcystins, as well as drawbacks and future needs in this field of research.     

淡水养殖池塘水质评价指标体系研究(英文)

[目的]建立淡水养殖池塘水质评价指标体系。[方法]通过专家访谈法、问卷调查法、实地调研法及DELPHI法,在综合分析淡水养殖池塘水质各影响因子的基础上,对14个淡水养殖池塘水环境因子的重要程度进行了排序,选择其中5个因素作为指标建立了淡水养殖池塘水质评价指标体系,并确定了各指标的阈值。[结果]淡水养殖池塘水质因子重要程度排序为溶解氧>pH>浮游植物量>透明度>总氮>浮游动物量>水温>生化需氧量>水色>盐度>总硬度;根据重要程度的大小,确定溶解氧、pH、透明度、浮游植物量、总氮5个指标为池塘水质评价的指标体系。对淡水养殖池塘水质等级进行5级划分,并采用专家问卷方法获得鱼类对各指标的耐受程度范围。[结论]为淡水养殖池塘水质评价提供了理论依据。     

土地利用变化对农业文化遗产系统结构的影响——以浙江省德清县为例

德清县是中国重要农业文化遗产——德清淡水珍珠传统养殖与利用系统的所在地,20多年来,在快速的城镇化进程中,德清县土地利用方式发生了较大变化。为刻画近年来德清土地利用变化特征,揭示其对农业文化遗产系统结构产生的影响,本研究基于访谈资料、第三次国土资源调查数据以及GlobeLand 30土地利用数据等进行了分析。结果表明,德清县在产业结构升级与城镇化扩张推动下,自2005年到2020年建设用地增加了53.36 km²,耕地减少了62.33 km²;在环境治理政策、经济效益和多种技术的综合作用下,养殖水面的面积快速增加,15年内共增长了117.75 km²;但桑地因经济效益不佳,1992年到2019年间面积减少了19.76 km²。在空间分布上,变化主要集中在东部水网平原区,这也是德清淡水珍珠传统养殖与利用系统所在地。研究显示,土地利用方式的转变,改变了当地“粮桑鱼畜”这一传统生态农业景观的结构及其背后的生态过程,减弱了不同土地利用方式之间的物质能量流动与循环,使得遗产系统面临较大的威胁。未来应进一步提高...     

Could European marine conservation policy benefit from systematic conservation planning?

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The potential exceptional role of a small Baltic boulder reef as a solitary habitat in a sea of mud

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