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进行了百草枯(paraquat)对尖膀胱螺(Physa acuta)成体及其胚胎各发育期(囊胚期、担轮幼虫期、面盘幼虫期和仔螺孵化期)的急性毒性实验.结果表明,百草枯对尖膀胱螺成体72 h和96 h LC50分别为2.53 mg/L和1.41 mg/L;对其胚胎各个时期72 h LC50分别为2.63、2.45、2.07、1.53 mg/L;96 h LC50分别为1.63、1.41、1.25、0.60 mg/L.百草枯对尖膀胱螺成体及其胚胎各发育期均有一定的毒性效应,胚胎比成体敏感,对胚胎各发育期的毒性也不同;随着染毒时间的延长,胚胎敏感性逐渐增强.研究表明,当百草枯进入水生态系统时,有可能对尖膀胱螺及其种群稳定造成影响. 相似文献
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为研究养殖皱纹盘鲍(Haliotis discus hannai Ino)外壳附着牡蛎的防除方法,对比了疣荔枝螺(Thais clavigera Kuster)、润泽角口螺(Ceratostoma rorifluum)和甲虫螺(Cantharus cecillei)对鲍外壳表面牡蛎的防除效果。以桑沟湾筏式养殖鲍为研究对象,自7月中旬开始,每隔15 d左右分别投放3种螺到鲍养殖笼中,共投放6次,以始终未投放螺的养殖笼为对照组。结果显示,实验结束时甲虫螺组中鲍壳上平均存活牡蛎数目为(0.04±0.04)个/只,疣荔枝螺组和润泽角口螺组疣荔枝螺组分别为(2.49±0.91)个/只和(2.21±1.05)个/只,对照组为(3.33±0.46)个/只。投放3种螺组中鲍壳上存活牡蛎数均显著显著低于对照组(P<0.05),甲虫螺也显著低于其他2种螺(P<0.05)。投螺时间也会影响螺防除牡蛎污损的效果,投放时间过晚会导致螺捕食牡蛎后有明显的壳残留,牡蛎的壳高达到0.5 cm左右再投放螺即可保证防除效果。另外甲虫螺组鲍壳上死亡牡蛎残留壳长度为(0.73±0.27) cm,显著低于疣荔枝螺组... 相似文献
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大瓶螺(Ampullariagigas),又名福寿螺、苹果螺,属软体动物门,腹足目,瓶螺科,瓶螺属。该螺含丰富的蛋白质、脂肪、维生素C、胡萝卜素及矿物质,养殖该螺对改善人们的食品结构和解决家禽、鱼、龟、鳖及虾蟹类的动物性饵料,具有重要意义。目前国内外对大瓶螺嗜食性及在不同光照下的摄食研究报道还较少。高本刚在《高效益水产动植物顾问》一书中对其做了一般性的闸述;胡自强等对其形态结构进行了研究;徐在宽对大瓶螺的心脏搏动与摄食量的关系进行了探讨;魏若飞等对大瓶螺理化耐性实验作了尝试;喜振生、毛盛贤、王彝豪等分别就大瓶螺在广州、北京… 相似文献
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利用扫描电镜对3种荔枝螺属种类-疣荔枝螺、黄口荔枝螺和瘤荔枝螺的齿舌进行观察.结果表明,荔枝螺齿式为0∶1∶1∶1∶0,即中央齿1枚,侧齿2枚,无缘齿.中央齿三分叉,中央齿尖长,其中黄口荔枝螺中央齿尖较其他2种略宽、短;两侧齿尖内侧各有1个小齿,其外侧具数量不等的小齿.侧齿细长,镰刀状,齿尖朝向与中央尖齿相同,其种间形态无明显变化.3种荔枝螺齿舌形态主要区别为中央齿两侧齿尖外侧小齿数目,其中疣荔枝螺小齿数最少,为5枚,瘤荔枝螺最多,为9～10枚,黄口荔枝螺为8～9枚. 相似文献
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利用PCR技术分别扩增皮氏蛾螺和水泡蛾螺的线粒体全基因组以及核糖体第二转录间隔区ITS2,对所得序列进行了分析。结果表明,皮氏蛾螺和水泡蛾螺的线粒体基因组全序列长度分别为15 255bp、15 265bp,具有相似的碱基组成和AT含量,其基因排列顺序完全一致,蛋白质编码基因长度相同,两种螺的ITS2分别为340bp和329bp,一致性达83.6%。经比对发现,皮氏蛾螺和水泡蛾螺的线粒体基因组及ITS2序列与已知的新腹足目动物相似。利用线粒体全基因组和核糖体序列构建系统发育树,两种序列的分析均显示皮氏蛾螺和水泡蛾螺亲缘关系较近。 相似文献
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长江新螺段江豚保护水域水质的时空变化 总被引：1，自引：0，他引：1
为了保护极度濒危的长江江豚(Neophocaena asiaeorientalis asiaeorientalis),了解其生活水域长江新螺段白鱀豚自然保护区水质的时空变化特征,探究水质状况的季节变化与地理变化差异,选用1992-2008年长江新螺段的水质监测数据资料,利用Kendall非参数趋势检验法分析枯水期、平水期和丰水期水体中溶解氧(DO)、氨氮(NH3-N)、总磷(TP)和总氮(TN)的变化趋势,并于2013年4月至2014年1月对该江段18个监测点的水温(T)、溶解氧(DO)、电导率(EC)、p H、总氮(TN)、总磷(TP)、硝态氮(NO3-N)、亚硝态氮(NO2-N)、氨氮(NH3-N)和六价铬[Cr(Ⅵ)]共10种水质指标进行监测分析。Kendall检验结果表明,1992-2008年长江新螺段水质状况整体无显著性变化,其季节性变化特征为枯水期水体污染物浓度高于平水期和丰水期。2013-2014年的水质监测结果表明,与2008年前相比,长江新螺段水质状况明显恶化,水体中的TN、TP和Cr(Ⅵ)污染情况较为严重,其中TP和Cr(Ⅵ)的平均浓度均超过Ⅳ类水质标准,且水质季节性变化特征也发生了相应改变。层次聚类分析将长江新螺段的18个监测点分为5个地理组,水质指标差异比较结果表明,陆溪河口的水质状况最好;临湘市化工园区排污口的水质状况最差,是长江新螺段的主要污染源;洪湖市生活废水的输入可能是新港码头附近水域中NH3-N浓度较高的原因。 相似文献
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测定了细角螺(Hemifusus termatamus)腹足部肌肉的氨基酸含量与脂肪酸组成,并与方斑东风螺(Babylonia areolata)、管角螺(Hemifusus tuba)、棘角螺(Hemifusus kawamurai)和鲐鱼(Pneumatophorus japonicus)进行了比较。结果显示,细角螺肌肉中检出17种氨基酸,总含量为肌肉干重的81.03%,高于鲐鱼(79.86%)、方斑东风螺(66.45%)、管角螺(56.94%)和棘角螺(64.42%);肌肉中4种呈味氨基酸(天冬氨酸、谷氨酸、甘氨酸和丙氨酸)的含量为38.49%,占氨基酸总量的47.50%;8种必需氨基酸(EAA)总含量为38.49%,占氨基酸总量的46.94%。细角螺肌肉中共检出20种脂肪酸,其中饱和脂肪酸的含量为65.25%,不饱和脂肪酸的含量为34.75%,不饱和脂肪酸与饱和脂肪酸含量的比值为0.53,低于方斑东风螺(1.15)、管角螺(1.13)和棘角螺(0.69),高于鲐鱼(0.37)。结果表明,细角螺肌肉中必需氨基酸与不饱和脂肪酸含量较丰富,具有较高的营养价值,是一种较为理想的食物蛋白与脂肪来源。 相似文献
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LI. Kangmin 《Fisheries Management and Ecology》1999,6(1):71-81
The economic development of the cities around Lake Taihu, China, has caused both environmental changes and ecological succession. The biodiversity of Lake Taihu has declined since 1970. Migratory fish, including anadromous, catadromous and semi-migratory fish, are either extinct or on the verge of extinction in Lake Taihu. Only lake dwellers persist. Several measures have been taken, such as restocking, closed seasons, sanctuaries for enhancement and even introductions to restore some original fish communities. Although these measures have achieved a certain degree of success, increased fishing activities or over-fishing have offset the benefits obtained. Moreover, cultural eutrophication of the lake and the pollution of the waterways connected with the lake are getting worse. This jeopardizes the remaining economically valuable species in the lake. Measures are required not only to control eutrophication and pollution, and to reduce the intensity of fishing, but also to address the wider biodiversity issues. 相似文献
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探讨浮游动物群落结构与环境因子的关系,为太湖水质监测提供方法,为富营养化治理与水生态修复提供理论支持。2016年8月进行了太湖水质状况及浮游动物群落调查,利用物种多样性指数和物种丰富度指数分析了太湖浮游动物群落结构特征,在此基础上,采用典范对应分析(CCA)探讨太湖浮游动物群落结构特征与环境因子的相互关系。结果表明,太湖不同湖区湖滨带水体水质总体评价为劣V类,总氮、总磷均值分别为(2.06±0.13)mg/L、(0.22±0.02)mg/L,叶绿素a平均含量为(65.35±9.09)mg/L。本次调查共检出浮游动物29种,其中桡足类5种,枝角类8种,轮虫16种;太湖浮游动物密度均值为(100±11)个/L,其中竺山湾浮游动物密度最高,为(273±54)个/L,胥口湾密度最低,仅为(31±6)个/L;太湖浮游动物生物量均值为(4.45±0.99)mg/L,生物量最高的是竺山湾,为(17.70±6.48)mg/L,胥口湾浮游动物生物量最低,为(1.03±0.23)mg/L。相关性分析表明,浮游动物各表征指标均与叶绿素a含量呈现显著正相关性。典范对应分析结果表明,浮游动物分布主要与溶解性总氮、总磷、透明度、溶解氧及pH值显著相关。 相似文献
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Chunfang Cai Xiaohong Gu Yuantu Ye Caigeng Yang Xiuying Dai Dongxing Chen Chao Yang 《Aquaculture Research》2013,44(5):795-806
China is the world's largest producer of aquatic animals, and the Taihu Lake area is one of the most important contributors within China. To obtain the basic information needed to minimize environmental impacts of aquaculture, the water quality and volume of effluents from 48 ponds used for raising crab, shrimp, river prawn, black carp, grass carp and turtles near Taihu Lake were monitored, and their pollutant loads were estimated. Effluent volumes ranged from 12.7 ± 1.7 (crab) to 50.9 ± 15.8 (turtle) thousand tons ha?1 year?1. The concentration of pollutants in the effluents often exceeded acceptable limits for Taihu Lake. Crab ponds produced the lowest gross loads of total nitrogen, total phosphorus, chemical oxygen demand and total suspended solids, whereas turtle ponds produced the highest. The net loads of monitored pollutants comprised only 4–53% of the gross loads in crab ponds, but > 50% in other species ponds. Results indicate that the pollutant loads discharged from aquaculture ponds around Taihu Lake are mild, but precautions are still needed to treat the wastewater. Connecting the ponds in series with crab ponds downstream is a feasible way to decrease pollutant loads. 相似文献
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太湖不同区域浮游植物群落结构特征及其与环境因子的关系 总被引：1，自引：0，他引：1
为研究太湖不同区域浮游植物群落结构特征及其与环境因子之间的关系,对水质状况进行调查,于2013年10月至2015年7月对太湖9个湖区的33个采样点进行了季节性浮游植物群落调查和水质监测,共鉴定出浮游植物121种,分别属于7门、74属,其中绿藻门(Chlorophyta)的种类最多,共28属、59种。春季和夏季浮游植物总密度最高值分别出现在2014年竺山湖0.59×10~8个/L和西部沿岸区5.90×10~8个/L,秋季和冬季浮游植物总密度最高值分别出现在2015年的西部沿岸区1.09×10~8个/L和湖心区3.28×10~8个/L。综合分析2年的浮游植物总密度监测数据,西部沿岸区梅梁湖竺山湖五里湖湖心区贡湖南部沿岸区东太湖东部沿岸区。研究表明,太湖9个区域污染情况不尽相同,主要超标指标为总氮。SPSS 22.0相关性分析表明,水温、DO、硝态氮、BOD5是影响太湖浮游植物群落结构的主要环境因子。2015年秋冬季浮游植物总密度较2014年有所增长,春季各湖区之间浮游植物密度的年际差异与其余季节不同,可能是由于水温变化所致。 相似文献
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T.R. McClanahan 《水产资源保护:海洋与淡水生态系统》2007,17(4):409-419
- 1. Justifying the designation of protected areas often depends on the ability to select areas in good ecological conditions, with high taxonomic richness, and unique habitats or species assemblage characteristics.
- 2. The ecology of scleractinian coral and prosobranch snails were examined along the Masoala Peninsula of north‐eastern Madagascar using rapid assessment methods to evaluate the correspondence between unique invertebrate faunal characteristics and park designation.
- 3. The reefs along this peninsula are in good ecological condition and have a coral and snail fauna similar to most of the western Indian Ocean, with no indications of local endemism in these groups. There was no relationship between the taxonomic richness of snails and corals. Corals were better at distinguishing locations based on taxonomic richness while snails were better based on unique faunal characteristics.
- 4. Corals had the highest taxonomic richness on the extreme windward north and south and the lowest richness on the leeward side of the peninsula. The leeward side did, however, have an unusual habitat of corals growing on granite rock with a unique coral and snail fauna. A northern and southern assemblage characterized snail fauna on the windward side of the peninsula.
- 5. The composite findings indicate that the currently designated park areas cover two of the three areas that have either high diversity or unique faunas.
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为了解南太湖水域近年来水质状况,以及蓝藻生物量与氨氮和总氮之间的变化规律,实验采用统计学方法,对南太湖水域3个入湖口(小梅港、新塘港、大钱港)水质中蓝藻生物量、氨氮和总氮的年变化特征进行了调查;使用SPSS10.0中的Bivariate(pcarson)软件对蓝藻生物量与氨氮和总氮的相关性进行了分析。结果表明:(1)南太湖入湖口蓝藻生物量一般有两个高位期,一个是在每年5—6月,另一个在每年的9—10月;(2)南太湖入湖口的总氮浓度处于富营养水平,并有向重富营养化发展的迹象;(3)蓝藻生物量与氨氮浓度的相关性系数r介于0.102～0.290,呈现不相关;(4)2008—2009年蓝藻生物量与总氮浓度的相关系数r介于0.010～0.210,呈现不相关;2010年蓝藻生物量与总氮浓度的相关系数r介于0.430～0.474,呈现低度负相关。结果说明南太湖入湖口的氮营养盐已经不容忽视,湖泊中氨氮和总氮浓度升高,将为蓝藻的繁殖生长提供条件,蓝藻一旦暴发,氨氮和总氮浓度反而迅速降低,在南太湖水域蓝藻生物量与氨氮和总氮浓度之间存在一定的此消彼长规律。 相似文献
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杂交青虾“太湖1号”肌肉营养成分分析 总被引：1，自引：1，他引：1
本试验以池塘养殖太湖青虾为对照,对杂交青虾"太湖1号"营养成分进行了分析。结果显示:杂交青虾"太湖1号"肌肉的水分、粗灰分、粗脂肪、粗蛋白含量与对照组差异不显著(P>0.05)。实验组与对照组氨基酸总量分别为79.5%和80.84%,差异不显著(P>0.05);必需氨基酸指数(EAAI)分别为66.32%和66.94%,构成比例符合联合国粮农组织/世界卫生组织(FAO/WHO)的标准,差异不显著(P>0.05);脂肪酸中EPA和DHA总量分别为0.83%和1.74%,差异不显著(P>0.05);主要微量元素比例合理,与对照组差异不显著(P>0.05)。研究表明,杂交青虾"太湖1号"肌肉主要营养成分与太湖青虾基本一致,两者没有显著差异。 相似文献
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Abstract – The native and non-native freshwater fish species richness as well as the proportion of native fish species to overall fish species were examined to test a hypothesis of a spatial linkage between the distributions of dams and non-native fishes based on survey data collected in rivers and streams in Hokkaido, Japan. Non-native fish species have steadily increased in Hokkaido since the mid 1970s, as indicated by the decreasing proportion of native fish species per fish survey. Non-native species richness was significantly higher in areas above dams (i.e., reservoirs and their inlet streams) compared to areas without dams. As a result, the proportion of native fish species was lower above dams. This proportion was lower in developed and agricultural areas compared with forest areas, although both native and non-native species richness were higher in areas with development and agriculture. Non-native cyprinids, catfish and snakehead occurred primarily in a particular river basin with the largest drainage area, the longest history of reclamation and highest human population in the island. Non-native salmonids on the other hand, occurred in forest areas at higher elevations and their occurrence was associated with the existence of dams. There was a spatial linkage between the distribution of dams and non-native species, although it was applicable only to salmonids. The management of dams and reservoirs needs a strategy to prevent further expansion of exotic salmonids such as rainbow and brown trout. These species can be a significant threat to native Japanese salmonids as a result of various biological mechanisms. 相似文献
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A field survey and a laboratory experiment were conducted to examine ontogenetic shifts in habitat and diet of the turban snail Turbo cornutus. The main habitat of turban snail juveniles smaller than 10 mm shell height (SH) was turfs of articulated coralline algae, and that of adults larger than 50 mm SH was kelp beds of Ecklonia bicyclis and Ecklonia cava. However, the ontogenetic habitat shift during the juvenile stage of 20–50 mm SH was unclear. From the results of a long-term feeding experiment and stable isotope analysis, the gelidiacean alga Gelidium elegans was assumed to be more important as a food source for juvenile turban snail than E. cava in the field. However, the frequency of individuals inhabiting gelidiacean algal turfs was low in both juvenile and adult stages. Thus, the ontogenetic shifts in habitat and diet did not coincide and other factors, i.e., daytime refuge, are important. As the growth rate was higher in the juveniles fed on the two algal species than those fed on single algal species, co-occurrence of various algal habitats in rocky shore ecosystems as a coastal ecosystem complex may enhance growth of turban snail juveniles feeding on a combination of different algal species. 相似文献
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不同增养殖水体中华绒螯蟹肌体矿物元素比较分析 总被引：2，自引：0，他引：2
对不同增养殖水体中华绒螯蟹可食部分主要矿物元素等指标进行分析研究,结果表明:中华绒螯蟹可食部分含9种以上矿物元素,雄蟹矿物元素中平均值以钙含量最高,雌蟹矿物元素平均值以磷含量最高。中华绒螯蟹钾的含量明显高于钠。比较不同增养殖水体雄蟹常量元素含量,固城湖放流与长江野生蟹无显著差异(P>0.05),均较其它水体雄蟹高,雌蟹常量元素太湖网围与长江野生无显著差别(P>0.05),含量都较高,尤以太湖网围常量元素含量为最高。雄蟹、雌蟹微量元素呈现相同规律:铁、锰以金坛池塘、固城湖放流含量较高。铜含量以长江野生为最高。锌含量各水体无显著差别。 相似文献