崇西湿地冬季潮滩鱼类种类组成及多样性分析

根据2006年冬季在崇西湿地进行的光滩和草滩插网渔获调查,首次对冬季长江口潮滩鱼类种类组成、多样性及相关环境因子作了分析。结果表明：冬季崇西湿地潮滩鱼类主要由淡水小型鱼类组成,共23种,隶属7科,20属。光滩和草滩插网的最大优势种皆为油,两种网具的渔获种类组成具一定的相似性。在一个潮周期内,3种多样性指数D、H′ 和J值波动范围较大,小汛潮时多样性指数比其它潮汛低。白天和晚上潮水的鱼类种类数无显著变化（P>0.5）,但在个体数和生物量上白天较晚上潮水高（P<0.5）。水温、潮汐大小对潮滩鱼类丰度影响较大,而与盐度相关较小。此外,天气状况也是影响潮滩鱼类的一个重要因子。总之,潮滩鱼类的种类组成和多样性受到各种环境因子的综合影响。     

藻毒素复合污染对鱼体的免疫毒性研究

针对水体富营养化问题,通过单一暴露和联合暴露方式研究两种MCs四种暴露剂量（0．1,1,10,100μg／L）下对鱼体的免疫毒效应。结果发现,不同剂量MCLR和MCRR单一暴露都能使鲫鱼淋巴细胞发生死亡,呈现明显的剂量效应和时间效应关系。且MCLR对鱼体的毒性相对McRR要更显著;MCLR和McRR复合暴露对鱼体淋巴细胞的毒性效应表现为协同作用,且随着毒素浓度的增加,其毒性效应差异显著性也随之升高,故而鱼体的免疫系统造成重大的影响,因此应当加强控制藻毒素在水体中的复合污染。     

三丁基锡生殖毒性的研究进展

有机锡化合物,特别是三丁基锡,广泛存在于环境中,对生物体以及生态环境存在着潜在的威胁。本文综述了三丁基锡对软体动物、鱼类和哺乳动物生殖机能的影响及其其可能的作用机制,指出了进一步的研究方向。     

大型河流大面积死鱼应急监测案例分析研究

以湖南湘江干流大面积死鱼突发环境事件为例,详细阐述了该事件开展应急监测的全过程,并就河流大面积死鱼突发环境事件应急监测方案、监测指标确定、原因分析等内容进行探讨。溶解氧低是死鱼的主要原因,而大体量低溶解氧污染团的形成与持续高温干旱天气、暴雨以及特殊的开闸放水方式有关。所分析的案例为死鱼事件应急监测工作提供借鉴和参考。     

滇池几种鱼体汞含量与δ13C、δ15N特征

鱼体是人体摄入甲基汞的重要暴露途径。对滇池几种重要鱼类的总汞、甲基汞和13 C、15 N进行了测定,结果发现:滇池中鱼体总汞和甲基汞含量范围(平均值)分别为5.6~287ng/g(74±59ng/g)和2.7~400ng/g(73±67ng/g)。总汞和甲基汞含量存现显著的相关关系,(R2=0.65,p0.001),且甲基汞占总汞的平均比例大于80%,表明鱼体中的汞主要以甲基汞的形态存在。滇池几种鱼类的δ13 C平均值为-20.5±4.2‰,范围为-29.0‰~-15.1‰,δ15 N平均值为17.1±4.3‰,范围为5.9‰~25.8‰。同位素比值与鱼体汞含量之间没有显著的相关性,可能是由于滇池中采集的黄颡鱼和白鱼与其他鱼类不属于同一种食物源,因此对13 C和15 N的分馏不同。另外,采集的鱼类大小和年龄不均一,也可能是造成13 C和15 N异常分馏的原因之一。     

Seasonal fluctuations of DDTs and PCBs in zooplankton and fish of Lake Maggiore (Northern Italy)

Concentrations of DDTs and PCBs were determined in the zooplankton and in three different fish species (shad, whitefish and roach) collected seasonally during 2009 and 2010 in three sites in Lake Maggiore, a south-alpine lake that has been contaminated by DDT since 1996. As previously observed in 2008, even during 2009 DDTs concentrations were higher in zooplankton than in fish, probably due to the very unstable situation of the lake still influenced by local inputs. The situation changed in 2010, when all DDT compounds increased in fish to levels much higher than those measured in zooplankton. Biomagnification was statistically demonstrated for pp′DDE in all the three fish species, indicating a probable signal of recovery of the lake.Although with respect to total PCBs we observed that the contamination levels varied across time periods and across fish species, biomagnification was evident from zooplankton to fish both in 2009 and in 2010. As concern individual PCBs, biomagnification from zooplankton to all three fish species was significant for PCB 153 and PCB 138.     

Species composition and quantitative representation of fishes in biotopes with the riffle minnow <Emphasis Type="Italic">Alburnoides bipunctatus</Emphasis>

Species composition of fishes was studied in rivers (capture sites) inhabited by the riffle minnow. In some localities, this species proved to occupy a leading position in the ichthyofauna, being obviously dominant. In small rivers, 16 species were caught together with it, including seven species regularly occurring in catches. The relative abundance of riffle minnow showed a moderate positive correlation with that of the gudgeon (0.568) and a nonsignificant negative correlation (?0.399) with that of the bleak. It is probable that the population dynamics of riffle minnow are determined mainly by natural intraspecific mechanisms rather than by water quality, which has changed only slightly in the rivers studied.     

大渡河流域电站建设对保护鱼类的影响及对策措施研究

为弄清大渡河流域电站建设对虎嘉鱼等5种保护鱼类的影响情况，探索适宜的保护措施，在流域枯水和丰水期分别选择了电站建设上下游6个有代表性的断面采集水样，采用电感耦合等离子发射光谱法等方法测定了重金属元素等16个指标，用单因子和综合指数评价法对电站上下游水质进行了对比评价；采用实地调查的方法调查了5种保护鱼类在近10年间种群数量的变化趋势。结果表明：电站建设对水质综合影响指数在1．64—1．82之间，影响严重；5种保护鱼类种群数量近10年间急剧下降，目前已为未见或罕见。     

The health risk assessment of organochlorine pesticides in smoked fish products available in Szczecin,Poland

The aim of this study was to determine the concentration of organochlorine pesticides [HCH and isomers (α, β, γ), aldrin, dieldrin, endrin, heptachlor and heptachlor epoxide and DDT and its metabolites (op’-DDD, pp’-DDD, op’-DDT, pp’-DDE, pp’-DDT] in smoked fish. Analysis was made of 12 typical smoked fish products that are the most popular among customers from the city of Szczecin, Poland. Pesticide residues were found in all samples of smoked fish. The smoked sprat and cold-smoked Baltic salmon were the most contaminated smoked fish products in terms of chlorine pesticides. The sum of DDT metabolites ranged from 1.48 (smoked mackerel) to 35.53 ng/g wet weight (smoked sprat), with the lowest concentrations found for op’-DDT and the highest for pp’-DDE. The level of heptachlor epoxide isomer B was low and ranged from 0.06 ± 0.01 (smoked eel) to 0.27 ± 0.07 ng/g w.w. (smoked sprat). The content of heptachlor was 0.48–1.99 ng/g w.w. Concentration of endrin was higher compared to other pesticides, ranged from 1.50 (cold-smoked salmon fillet) to 16.84 ng/g w.w (hot-smoked warehou). The contamination of smoked products was significantly low and poses no risk to the health of consumers provided that they eat a diverse diet. The concentration of organochlorine pesticides in the analysed products was below the standards accepted in European countries.     

Prymnesium parvum: The Texas Experience1

Southard, Gregory M., Loraine T. Fries, and Aaron Barkoh, 2010. Prymnesium parvum: The Texas Experience. Journal of the American Water Resources Association (JAWRA) 46(1):14-23. DOI: 10.1111/j.1752-1688.2009.00387.x Abstract: Golden alga Prymnesium parvum was first identified in Texas during a fish kill investigation on the Pecos River in 1985. Since then golden alga kills occurred sporadically in a variety of waters in the western part of the state until 2001 when the alga became endemic in the Brazos, Canadian, Colorado, Red, and Rio Grande river systems, including the water supplies of two public fish hatcheries, the Possum Kingdom and Dundee state fish hatcheries. The increasing area adversely affected by the alga and frequent massive fish kills heightened public and political awareness and concerns regarding the ecological and economic impacts of P. parvum blooms. The Texas Parks and Wildlife Department (TPWD), the wildlife conservation agency of the state, responded to these concerns with a program to assess the ecological and economic impacts and to develop management options. To date 33 water bodies have been affected and losses are conservatively estimated at 34 million fish valued at US$13 million. Several sport fisheries, including smallmouth bass Micropterus dolomieu, striped bass Morone saxatilis, channel catfish Ictalurus punctatus, and blue catfish Ictalurus furcatus, have been severely affected. Additionally, 26 imperiled fish species occur in the affected water basins and some have been adversely affected. Economic losses associated with reduced fishing and other water-based recreational activities appear considerable. The combined economic losses to three counties (Palo Pinto, Stephens, and Young) surrounding Possum Kingdom reservoir for 2001 and 2003 were estimated at US$2.8 million and US$1.1 million, respectively. This paper describes how the TPWD responded to public and political concerns relative to the emergence of golden alga, its harmful effects to fisheries, and its historic and current statewide distribution.