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湛江红树林湿地水体重金属污染评价及来源分析 总被引：2，自引：0，他引：2
通过研究湛江红树林湿地水体重金属的含量、空间分布特征和来源及环境因子的影响,旨在为红树林湿地保护提供理论依据。选取湛江市范围内10处红树林湿地、共38个采样点,其中廉江(样点1~6)、遂溪(样点7~10)、雷州西海岸(样点11~12)、徐闻五里(样点13~16)、徐闻和安(样点17~21)、雷州东海岸(样点22~25)、麻章(样点26~29)、坡头(样点30~32)、霞山特呈岛(样点33~35)、东海岛(样点36~38),采集各样点水面下0.5 m处的3个混合水样用于理化指标测定,利用水质质量指数法对Cr、Cu、Pb、Cd、Ni、Hg 6种重金属的污染水平进行综合评价;利用最小显著差异检验(LSD)进行单因素方差分析,比较不同研究区域水体重金属及理化性质差异;利用主成分分析判断湛江红树林湿地水体重金属的来源,并基于其特征值(1)判断主成分,并判断每个主成分中载荷量大的因子。结果表明,研究区水体中Fe、Mn、Cu、Cr、Cd、Pb、Ni和Hg等重金属含量较低,各区县水质综合污染指数平均值均小于1,除了霞山特呈岛、雷州东西海岸的个别样点外,总体上未出现明显的重金属污染;重金属单因子污染指数显示Cu和Ni污染问题相对突出。主成分分析结果显示,Fe和Cr为自然来源,Hg、Pb和Cu与人类活动中农业生产和生活污水排放密切有关,Mn、Ni和Cd主要来自工业综合污染。重金属与水体环境因子的RDA分析表明,TOC和pH是影响水体重金属分布的显著性因子。 相似文献
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夏季扎龙湿地底栖动物双向指示种(TWINSPAN)分类与水质生物监测 总被引：1，自引：0，他引：1
2011年夏季对扎龙湿地夏季底栖动物种群结构和水质状况进行了综合研究,期间应用双向指示种(TWINSPAN)分析技术,以7个采样点的数据为基础,对各采样点进行了归纳分类。结果显示:扎龙地区水域可以划分为3个类型,6#翁海排干和7#东升水库污生指数(IBP)最小,水质最好,其次为2#采样点,水质稍差,为轻度污染,1#、3#、4#、5#水质较前两组差,3(#扎龙湖)和5(#龙湖)样点已达到β-中污染,但根据污生指数评价标准分析,扎龙湿地整体水质属于轻污染。 相似文献
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为了从常用的水质评价方法中筛选出适合珠三角河网的方法,该研究对2015年珠三角河网的水环境因子和浮游植物数据进行了初步的评价分析。运用自组织映射模型(SOM)从6种浮游植物评价指数中筛选出香农指数、均匀度指数、丰富度指数和生物量指数4种相似性高的指数,将上述指数和环境因子的水质评价结果进行对比分析。结果显示,基于溶解氧和氨氮的水质评价结果可以较好地反映城市周边与其他区域的空间差异,而总氮和总磷不适用于研究水域的水质等级评价;基于香农指数和生物量指数的水质评价结果可以较好地反映出城市周边与其他区域的差异,均匀度指数和丰富度指数不适用于研究水域的水质等级评价。除总氮、总磷外,其他环境因子和4种浮游植物指数的评价结果均反映为研究水域水质整体良好,城市周边站位水质略差。研究表明,溶解氧、氨氮、香农指数、生物量指数是适合研究水域水质等级评价的环境因子和浮游植物评价指数。 相似文献
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应用双向指示种(TWINSPAN)技术对海浪河春季的7个采样点进行分类和水质评价研究;共采集到环节动物、软体动物和节肢动物3大类,包括4纲7目9科14属共18种;结合污染指数,TWINSPAN分析结果表明海浪河春季采样点划分为四个类型,海浪河大桥6#点水质最好,其次为海南桥7#采样点,河夹大坝1#、2#点水质较差,3#、4#、5#采样点水质最差,但根据污染指数评价标准来看,水质都处于不同程度的污染状态。 相似文献
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为了解黄河流域湿地水生生物群落结构特征及生态环境现状，于2020年4月至2021年3月调查了济南段城市湿地—济西湿地公园浮游动物群落结构，监测分析了水环境因子变化特征及水环境质量状况。结果表明：济西湿地公园全年共采集鉴定出浮游动物4大类66种，平均密度为181.8 ind./L，平均生物量为0.210mg/L；浮游动物划分为7个功能群，春季、夏季、冬季均以功能群RF和PF为主，最高占比分别为62.86%、20.75%，秋季以功能群RF和SCF为主，占比分别为58.54%、12.20%；浮游动物Shannon-Wiener指数(H'')、Pielou均匀度指数(J)和Margalef丰富度指数（D）平均值分别为2.50、0.71、2.31；综合营养状态指数水质评价结果显示济西湿地公园水质整体处于中营养化水平；Pearson相关性分析表明WT、COND、DO、NO2--N、SS、TP、PO43-和Chl-a是显著影响浮游动物功能群的主要环境因子。该研究对济西湿地的生态效应评估和水资源保护具有一定的指导意义。 相似文献
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草海高原湿地湖泊水质时空变化及水质分区研究 总被引：4，自引：0，他引：4
针对草海水质污染状况,开展水质季节变化特征研究,为草海湿地污染治理及保护提供依据。在草海湿地湖泊设置了15个采样点,于2014年8月、11月和2015年1月、4月,分4季进行水样采集。以所测水质参数为基础,运用水质综合评价和GIS空间分析方法,研究草海湿地水环境质量时空变化,并基于营养状态对湖泊水体进行了分区。研究表明:(1)草海TP、TN、CODMn、Chl-a 4种主要水质指标浓度在春季高于其他3个季节,浓度分别达到0.03、0.98、6.30和0.025 mg/L,空间分布呈现由东至西逐渐降低的趋势,草海入水口及码头区域要明显高于湖泊其他区域。(2)草海湖泊营养状态为中营养级别,按4个季度的综合营养状态指数(TLI)平均值分为3个区域,A区为东北角入水口及西海游客码头,长年处于富营养状态,为富营养状态区,53.9≤TLI≤63.0,水质处于Ⅳ与Ⅴ类等级;B区为临近县城及入水口区域,季节性富营养状态,为中营养状态区,41.2≤TLI≤46.6;C区为草海湖泊中心延续到阳关山的下游出水口区域,为贫中营养状态区,35.8≤TLI≤39.7;B区和C区水质全年为Ⅲ类等级。(3)各区域主要污染物指标以Chl-a、TN为主,A区形成的主因是城市污水注入,B区形成的主因是农业面源污染。控制城市污水和农药、化肥施用量是治理草海湖泊水环境的重要途径。 相似文献
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为客观评价环渤海13个城市近岸海域水质状况,验证雷达图指数、内梅罗指数和主成分指数在渤海近岸海域水质评价中的作用,基于渤海195个监测站位3、5月两次实测水质数据,选取化学需氧量、无机氮、总氮、活性磷酸盐、总磷和石油类物质作为评价因子,对环渤海主要城市近岸海域水质状况进行了综合评价和等级划分。结果显示,渤海近岸海域主要污染物为无机氮和总磷,其次为石油类物质;葫芦岛、秦皇岛、大连和烟台的近岸海域水质状况较好,而位于辽东湾北岸辽河口附近的盘锦、锦州、营口以及位于莱州湾西侧的滨州的近岸海域水质状况较差;3类水质综合指数对海水中盐度和悬浮物浓度敏感性较强,且相互之间及其与水质优良面积比例存在显著相关性,表明所选择的3类水质指数能够真实反映渤海近岸海域水质状况。本研究将为渤海水质评价与综合治理成效评估提供方法上的借鉴。 相似文献
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2015年全年对秀丽高原鳅(Triplophysa venusta)主要分布流域漾弓江上游鹤庆段开展水质调查,对洗马池、白龙潭、清水河、寺庄龙潭、美龙潭、西龙潭、人工驯养池及驯养池水源8个监测点的水温(T)、pH、溶解氧(DO)、氨氮(NH3-N)、总氮(TN)、总磷(TP)、高锰酸盐指数(CODMn)7个指标进行采样监测,采用模糊综合评价法和综合水质标识指数法对采样点水质现状进行评价;分析了人工驯养池和自然栖息地水质差异。结果显示:驯养池与自然栖息地部分水质指标差异显著;自然栖息地中,清水河夏季水质为Ⅲ类,主要污染物为TN,其余监测点各季节水质均满足水体环境功能区规划要求;驯养池夏季水质评价结果为Ⅳ类,主要污染物为TN。 相似文献
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阳澄西湖及其入湖港口的水质评价与分析 总被引：1，自引：0，他引：1
为了探明阳澄西湖湖区及其入湖港口的水质现状,为其后续水环境治理提供参考,选取湖区6个位点和4个港口,于2016年5月至2017年3月监测其水质,逢单月月初采样;监测的水质参数包括水深(H)、酸碱度(pH)、溶解氧(DO)、透明度(SD)、悬浮物(TSS)、总氮(TN)、氨氮(NH~+_4-N)、亚硝酸盐氮(NO~-_2-N)、总磷(TP)、活性磷酸盐(PO■-P)、叶绿素a (Chl-a)、高锰酸盐指数(COD_(Mn))、总有机碳(TOC)。运用主成分分析法探讨了水体主要污染因子,采用皮尔逊相关性分析法探究湖区TN、TP对Chl-a浓度的影响。结果显示,阳澄西湖水质综合营养状态指数年均值为57.9,主要水质参数的时空分布表现为枯水期(5-7月)优于丰水期(11-1月),湖区优于入湖港口,北部优于南部。湖区TN和TP年均值为2.63 mg/L和0.217 mg/L,Chl-a年均值为21.74μg/L,且以9月最低。主成分分析显示,NH~+_4-N、NO~-_2-N、PO■-P、TP、TN是湖区水质主要的污染因子,TP、NH~+_4-N、NO~-_2-N、TN是港口水质的主要污染因子。皮尔逊相关性分析显示,阳澄西湖的Chl-a浓度与TN呈正相关(P0.01),与TP的相关性不显著(P0.05),且相关系数为负值。研究表明,阳澄西湖的Chl-a对营养物质的响应不灵敏,后续治理中需加强对外源氮磷的拦截。 相似文献
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Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean 
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下载免费PDF全文 The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna. 相似文献
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In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg. 相似文献
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Liping Li Rui Wang Wanwen Liang Xi Gan Ting Huang Yan Huang Jian Li Yunliang Shi Honglin Luo Ming Chen 《广西水产科技》2014,(1)
Previously, we reported 10 PEGE types of 85 tilapia Streptococcus agalactiae(GBS), which shifted from Streptococcus iniae in China, by using PEGE method. Presently, larger and more representative tilapia GBS were isolated, for the ?rst time in China, to characterize their serotypes and genetic diversities more precisely than had done before. 168 GBS strains were distributed in ?ve provinces of China, in which Guangdong, Guangxi and Hainan were the major ones, holding36.9%(62/168), 37.5%(63/168) and 19.6%(33/168), respectively. Serotypes, Ia, Ib and III, were observed in these strains and the most predominant one was Ia(95.2%), which mainly distributed in Guangdong, Guangxi and Hainan. Ia initially occurred in 2009, it shoot up to 32.1% in 2010,but decreased to 16.1% in 2011 before went up to 45.2% in 2012. Ib sporadically occurred during2007–2011, III onlyoccurred in 2012. 14 different PFGE types, including 4 new types(N, O,P and Q), were observed, in which B, D, F and G were the predominant types, holding 83.9%(141/168) of the total GBS strains. Ia corresponded to 11 PFGE types(A–H, N–P), in which type D predominated(51%). Ib represented 3 genotypes(I, J and Q) and III harbored only 2genotypes(N and F). Type N and Fsynchronously presented in Ia and III. In summary, the genetic diversity of tilapia GBS varied by serotypes and changed with geographical locations and years.Although Iastillpredominated, new rareserotypeIII alreadyoccurred in China. 相似文献
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Iciar Martinez Amaya Velasco Ricardo Pérez-Martín Eskil Forås Michiaki Yamashita Carmen G. Sotelo 《Journal Of Aquatic Food Product Technology》2013,22(4):289-297
The purpose of this work was to evaluate the suitability of a method based on the presence of two restriction sites (for Hae III and Hindf I) in the mitochondrial NADH dehydrogenase subunit 5 (mt ND5) gene to identify Scomber species. The evaluation was performed on 144 reference and market samples by sequencing of the entire 505-bp fragment of the mt ND5 gene and of a 464-bp fragment of the Kocher fragment of the cytochrome b gene (mt Cytb). Sequence analysis of any of the two fragments allows the identification of each of the four Scomber species, but S. japonicus and S. colias had the same restriction sites at the ND5 amplicon and would not have been differentiated by this analysis. Similarly, loss of the Hae III site in some S. scombrus individuals would have misidentified them as not being Scomber. All the market products were correctly labeled except one acquired in Spain labeled as originating in the Atlantic and containing S. japonicus. 相似文献
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Growth hormone (GH) and reproduction: a review 总被引：5，自引：0，他引：5
Florence Le Gac Odile Blaise Alex Fostier Pierre-Yves Le Bail Maurice Loir Brigitte Mourot Claudine Weil 《Fish physiology and biochemistry》1993,11(1-6):219-232
Interaction between growth and reproduction occurs in many vertebrates and is particularly obvious at certain stages of the life cycle in fish. Endocrine interactions between the gonadotropic axis and the somatotropic axis are described, the potential role of GH being emphasised. A comparative analysis of these phenomena in mammals, amphibians and fish, suggests a specific role of GH in the physiology of puberty, gametogenesis and fertility. It also shows the original contribution made by studies on the fish model in this field of investigations. 相似文献
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Two gonadotropins (GtH; Qa and Qb) were purified by gel filtration and ion exchange chromatography from the pituitaries of Indian walking catfish (Clarias batrachus). The presence of GtH during purification was assessed by in vitro oocyte maturation and in vivo steroidogenic activity, and their identities were determined by elution profiles, molecular weight, biological activities and yield. The molecular weights of Qa and Qb were 37 and 42 kDa, respectively, and composed of distinct subunits (Qa: 20 and 14 kDa and Qb: 26 and 18 kDa). Polyclonal antibodies raised against Qa immunostained Qa, Qb and pituitary GtH cells. A competitive Qa‐ELISA was developed whose sensitivity was 6.25 ng mL?1 (1.25 ng well?1) with intra‐ (3.5%) and inter‐ (12.4%) assay coefficients of variation. Displacement curves parallel to the standard were obtained with plasma and pituitary extracts of catfish, Qb and carp GtHII. The assay was validated by measuring the plasma Qa levels after LHRH treatment and in relation to ovarian growth in the female catfish during different reproductive phases. Based on the results, Qa and Qb corresponded to fish LH and FSH respectively. The findings will increase the knowledge of the mechanisms controlling fish reproduction and identification of sensitive phases in fish in captivity for hormonal manipulation. 相似文献
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Controlled infection of Poecilia reticulata Peters (guppy) with Tetrahymena by immersion and intraperitoneal injection 下载免费PDF全文
下载免费PDF全文 G Sharon M Pimenta‐Leibowitz M C L Vilchis N Isakov D Zilberg 《Journal of fish diseases》2015,38(1):67-74
Tetrahymena is a protozoan parasite, which infects guppy, Poecilia reticulata Peters, and causes substantial economical losses in commercial farms worldwide. Studies of guppy infected by Tetrahymena require standardized infection protocols. The LD50 for Tetrahymena infection of guppies by intraperitoneal (IP) injection was calibrated, and the level obtained was 946 parasites per fish. Guppy infection with Tetrahymena by immersion, imitating the natural route of infection via the integument, was studied under normal or stress conditions. Exposure to cold and netting (CNI) and to cold only (CI) followed by immersion exposure to 10 000 Tetrahymena per mL resulted in 22.5% and 19.2% mortality, respectively, as compared to 14.2% and 10% in groups that were netted only (NI) or non‐stressed (I). Histopathology revealed that immersion infection resulted in a systemic infection. Lysozyme levels, measured 3 weeks after infection, were significantly higher in the CNI group (288 μg per mg protein) compared with CI‐, NI‐ and I‐treated groups (94.5, 64 and 62.3 μg mg?1, respectively). There was no evident parasite immobilization activity in body homogenates, suggesting no development of acquired immunity. Re‐infection by IP injection revealed no increase in protection in any of the treatment groups, mortality range of 56.3–75%, higher than in the non‐exposed control (40.6% mortality). 相似文献
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