Marine Biotoxins of Algal Origin and Seafood Safety

Abstract

Harmful algal blooms occur with the unchecked proliferation of algae in the marine environment, which oftentimes results in the production of hazardous marine biotoxins. Marine biotoxins are produced by several dinoflagellate and diatom species (e.g., Alexandrium, Gymnodinium, Gonyaulax, Pyrodinium, Protogonyaulax, Dinophysis, Prorocentrum spp., and Pseudonitzchia spp.). Significant human health effects have been reported after exposure to these toxins, including disease syndromes such as Paralytic Shellfish Poisoning (PSP), Neurotoxic Shellfish Poisoning (NSP), Ciguatera Fish Poisoning (CFP), Amnesic Shellfish Poisoning (ASP), and Diarrhetic Shellfish Poisoning (DSP). Of more recent interest has been the emergence of newly discovered toxic dinoflagellates caused in part by the increase in human and environmental interactions along coastal waters. Most notably, Pfiesteria piscicida and Pfiesteria-like organisms have been associated with numerous fish kills and have stimulated public concern over the potential threat these organisms may have on human health and seafood safety. This paper reviews the current literature on marine biotoxins of algal origin, with particular attention to public health issues associated with seafood safety.     

云南12种外来林业有害生物的危害分析

对12种重要外来林业有害生物入侵云南的时间、媒介、入侵的地区、发生面积和危害趋势作了综合报道与分析。并结合危害实际,提出了有关的建议。     

不同抚育措施对毛竹叶螨种群密度及危害影响的研究

对毛竹叶螨发生的竹林进行劈草和锄草抚育,通过1a观察发现,锄草的竹林中的毛竹叶螨的种群密度和危害高于劈草的竹林。建议竹林抚育要因地制宜,对杂灌不繁茂、土壤较疏松的竹林不劈草。对杂灌繁茂的竹林于8～9月份劈草,尽量不锄草。释放捕食螨防治毛竹叶螨结果表明,捕食螨防治效果留草竹林大于劈草竹林、大于锄草竹林,所以毛竹叶螨的防治要与竹林抚育管理相结合,竹林在释放捕食螨防治毛竹叶螨的当年林下要留草,禁止全垦全劈。     

滇池水体氮的时空变化与藻类生长的关系

水体氮的时空变化及其与藻类生长的关系对研究水体富营养化具有十分重要的作用。采用GPS定位,对滇池海埂、斗南、罗家村、新街、昆阳5个代表性位点断面水体总氮、铵态氮、硝态氮及叶绿素a含量进行了为期1a的监测和动态研究,全面分析了不同区域、不同层次、不同时期滇池水体各形态氮的时空变化特征及其对藻类生长的影响。结果表明,全湖各采样点水体总氮、铵态氮、硝态氮的平均浓度分别是2.14、0.11、0.20mg·L-1,全年分别在0.66～6.44mg·L-1、0～0.74mg·L-1、0～0.94mg·L-1之间变化。各区域水体总氮的浓度以海埂和斗南最高,铵态氮和硝态氮的变化幅度较大。全湖水体总氮和铵态氮与叶绿素a呈显著正相关,硝态氮与叶绿素a呈负相关趋势;滇池不同区域水体总氮与叶绿素a呈显著正相关,海埂和罗家村位点水体铵态氮与叶绿素a呈显著正相关,海埂位点水体硝态氮与叶绿素a呈显著负相关,其他区域则无显著相关性;水体总氮、铵态氮、硝态氮对藻类生长的影响呈现显著的区域性和水层差异。     

一种检疫性有害植物——西部苋

阐述了检疫性有害植物西部苋的地理分布、形态特征、生物学特性、危害性、传播途径及防治方法,详细描述了西部苋与其近似种糙果苋在形态特征上的区别。     

采取自然防治措施,促进湿地松林健康发展——以江西省吉安市为例

概述了吉安市湿地松纯林有害生物的发生情况、自然防治的内容及实施途径。在综合防治中,提倡采取以营林技术措施为主体的自然防治方法,尽快恢复生物多样性,维持自然生态平衡,是湿地松纯林有害生物防治的根本途径,也是当前湿地松保护的主要内容。     

我国长江口及邻近海域铜藻生长和金潮分布变化特征

为了解金潮源头,对枸杞岛附近贻贝(Mytilus edulis)养殖区固着褐藻进行了分布特征调查,并对长江口附近海域漂浮金潮进行月度监测。结果表明,枸杞岛附近贻贝养殖区设施上固着生长大量褐藻马尾藻,1—3月,藻体具有固着器,营固着快速生长,平均长度在3月可达3.45 m;同时海区巡航监测结果显示,1—2月枸杞岛附近海域无漂浮马尾藻,3月份只有单棵零星漂浮藻体; 4月份,贻贝养殖区马尾藻固着器逐渐萎缩消失,导致藻体大量脱落进入海区,由于马尾藻具有气囊结构,能够保障藻体长期漂浮在海表面形成金潮;大面监测结果显示,4—5月海区漂浮褐藻生物量与分布范围快速增加,分布面积可达27761 km^2。分子生物学检测结果显示,固着褐藻和海区漂浮褐藻均为铜藻(Sargassum horneri)。本研究结果表明,3—4月浙江沿岸固着铜藻在人为和海流的共同作用下从贻贝养殖设施上脱落后营漂浮生活,生长聚集,并可能在风和海流作用下向北至黄海海域形成金潮,黄海金潮可能具有多溯源性质。     

汉江中下游硅藻水华研究进展与展望

汉江流域是多个引调水工程水源地,在国家水资源配置战略中具有重要地位,其水质安全问题一直备受关注。汉江中下游自1992年首次爆发水华以来,水华事件已累计发生10余次,给沿岸居民生产生活带来严重影响。本文系统调研了汉江水华相关研究进展,归纳分析了汉江中下游水华优势藻种及其生物学特性,统计分析了汉江中下游历次水华的发生特征,从营养盐、水文水动力、气象等条件方面归纳了现有研究成果中对于汉江中下游水华爆发成因的解释,总结了汉江中下游水华预测相关模型及水华可调控环境因子的阈值。当前汉江中下游水华防控面临新的挑战,未来仍需在环境因子对硅藻水华生消的影响机理、水华预测模型与方法、水华预警和抑制水华生态调度技术等方面继续开展深入研究。     

Assessment of rocky reef fish assemblages close to seaweed farming

The seaweed Kappaphycus alvarezii (Doty) Doty ex P. C. Silva, a red algal species, is the main global source of Kappa carrageenan. The introduction of such exotic species in regions outside their original locale can change the community structure of the areas into which they are introduced. The possible influence of seaweed farming on the rocky reef fish assemblage was assessed in Paraty, Brazil. The reef fish assemblage in the seaweed farming area was compared before and after the commencement of farming with two undisturbed control areas. Among the ten species ranked as the most frequently occurring in each area, eight were the same. The fish community structure close to the seaweed farming area did not change from that of the control areas, over the months of the study. Neither the fish diversity and richness indices, nor the total average abundance among areas was significantly altered. The average abundance of the different trophic groups varied over time in both the farm and control areas, revealing similar patterns. These results suggest that K. alvarezii can be cultivated up to at least 50 m from a rocky coast without altering the fish community structure of the surrounding waters.     

河蟹生态育苗池中几种常见生物对其溞状幼体的影响

研究了河蟹生态育苗池中最常见的糠虾、利氏才女虫幼体（ＰＬＬ）、桡足类与河蟹溲状幼体（Ｚ）间的关系。结果表明：糠虾严重影响Ｚ的存活与变态,其密度达３个／Ｌ时可使育苗绝产,应彻底杀灭。ＰＬＬ对Ｚ的危害随其密度的增大而加剧,当ＰＬＬ达５００个／Ｌ时即严重危害Ｚ１的变态（变态率为４０％,对照组为８０％）;在无轮虫的情况下Ｚ１的变态率更低（３０％）。Ｚ１可摄食体长小于０．４ｍｍ的ＰＬＬ,Ｚ５则完全可以ＰＬＬ