首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
This paper reports the growth pattern and length‐weight relationship and summarizes biological data for the clearhead icefish (Protosalanx hyalocranius) in Lake Khanka (Xingkai), on the border between China and Russia. The von Bertalanffy growth was estimated as SL = 20.3(1 ? e?2.93 (t ? 0.21)). The length‐weight relationship was W = 0.00448 SL2.99 for juveniles, and W = 0.000896 SL3.59 for adults. P. hyalocranius mature in December and spawn in January, when the lake is still covered with ice, then die after spawning. The larvae hatch in March. Juveniles feed mainly on zooplankton whereas adults also feed on other fishes.  相似文献   

2.
长江口沿岸碎波带刀鲚仔稚鱼的日龄组成与生长   总被引:2,自引:0,他引:2  
实验研究了长江口沿岸碎波带刀鲚仔稚鱼的日龄组成、孵化期、早期生长率和滞留时间。从2007年5-10月在长江口沿岸碎波带采集的刀鲚仔稚鱼中,共选取594尾(体长范围为3.0-30.5mm),划分发育阶段,并取矢耳石进行日龄分析。仔稚鱼日龄范围为7-34d,以13-18d日龄比例较高,占总数的50.1%;仔稚鱼体长(L,mm)与日龄(D,days)呈显著直线关系:L=0.73D+5.09,R2=0.74;孵化期为5月23日至10月4日,高峰期集中在5月末至8月上旬,且早期个体在孵化后7d左右开始进入到碎波带,在碎波带滞留约23d。    相似文献   

3.
&#  &#  &#  &#  &#  &#  &#  &#  &#  &#  &#  &#  &#  &#  &#  &#  &#  &# 《水生生物学报》2015,39(5):1019-1026
以长江刀鲚(Coilia nasus)洄游前幼鱼和洄游后成鱼为对象, 通过 PCR-DGGE 指纹技术探讨长江刀鲚菌群多样性及受洄游路径周围环境影响之后的稳定性。结果显示, PCR-DGGE 指纹谱带丰富, 共显示出70条可鉴别条带, 其中长江水体谱带数(28)高于洄游后刀鲚鳃(26)、胃(26)、肠道壁(20)、肠道内容物(21)和洄游前刀鲚鳃(21)、胃(20)、肠道壁(11)、肠道内容物(13), 洄游后刀鲚成鱼体内各对应部位菌群数显著高于洄游前刀鲚幼鱼。UPGMA 聚类和PCA 结果显示不同样品之间差异显著, 虽长江水体与洄游后刀鲚鳃、胃及肠道内容物样品在聚类图上聚为一簇, 但其菌群结构的相似度较低, 分别为43%、35%和28%。成功克隆测序其中43 条条带, 主要包含-变形菌(25.6%)、-变形菌(7%)、-变形菌(16.3%)、放线菌(25.6%)、厚菌门(9.3%)、拟杆菌(7%)、柔膜菌门(4.6%)、绿弯菌(2.3%)和未定义菌(2.3%)。以上结果表明长江刀鲚体内不同部位及其在洄游前后不同阶段, 菌群结构存在显著差异, 并受环境和宿主双层因素影响。    相似文献   

4.
Phylogenetic relationships among 15 species in the family Salangidae were constructed based on the complete cytochrome b sequence (1141 bp). We confirmed the monophyly of the family Salangidae and defined four primitive lineages within this family: (I) Protosalanx , Neosalanx anderssoni , Neosalanx tangkahkeii , and Neosalanx argentea ; (II) Neosalanx reganius , Neosalanx jordani , Neosalanx oligodontis , and Neosalanx  sp.; (III) Hemisalanx , Salanx , Leucosoma , and Salangichthys ishikawae ; and (IV) Salangichthys microdon . A major finding of our study is the key basal placement of Sg. microdon . According to the tentative estimation, the divergence of the four lineages appears to have been initiated in the early Miocene (21 Mya), with most speciation events occurring 1.05–9.90 Mya. Taxonomic revisions on subfamilial, generic, and specific levels were carried out based on phylogenetic relationships and genetic distance, taking into account some key morphological characters. The speciation mechanism in Salangidae is also discussed, and the evidence shows that geographical isolation, water mass, as well as some ecological factors, may not always play important roles in the speciation of temperate estuarine fish. In the most cases, sympatric salangids are not monophyletic, indicating that their coexistence reflects secondary contact rather than sympatric speciation.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 91 , 327–342.  相似文献   

5.
The Yangtze River estuary (YRE) is an important migration channel and foraging habitat for Coilia nasus. Due to its ecological significance and a prioritization of this species’ protection, the need to investigate and analyze environmental relationships of the abundance of Coilia nasus in the YRE as well as develop an understanding of their temporal and spatial distributions is becoming exceedingly important. Using fishery data and environmental survey data from 2009 to 2016, three models including generalized additive mixed models (GAMM), generalized additive models with zero-inflated Poisson distribution (ZIP-GAM) and two-step GAM were used to analyze relationships between environmental factors and the distribution of Coilia nasus in the YRE. The results showed that model fitting of GAMM was more consistent with observations and revealed influences of water temperature, salinity, chlorophyll, and pH on distribution. GAMM demonstrated that higher Coilia nasus abundances were located in waters with water temperature values at 15°C and 30°C, and lower Coilia nasus abundances were located in areas with water temperature values at 10°C and 20°C. All models indicated that the effect of salinity on abundance of Coilia nasus present a multimodal pattern including three peaks at 5, 15, and 25 ppt respectively. Additionally, abundance of Coilia nasus increased with the increase of chlorophyll A in its range of 0–4 mg/L. In a range of 8.0–9.5, higher PH value was more suitable for the aggregation of Coilia nasus. Cross validation was used to evaluate the predictive performance of models and GAMM was found to be the best. The predicted abundance distribution of Coilia nasus in the summer and autumn of 2016 was relatively higher overall than that in winter and spring. The predicted zero abundance distribution pattern was consistent with the sampling presence distribution which was obtained using fishery independent survey data of the year 2009–2015. Facing the urgency protection of Coilia nasus in YRE, results of this study could be used for Coilia nasus conservation and reserve planning.  相似文献   

6.
Aquatic biota have long been recognized as bioindicators of the contamination caused by hydrophobic organic contaminants (HOCs) in aquatic environments. The primary purpose of the present study is to identify which species of aquatic biota are the most sensitive to organochlorine pesticides (OCPs) in Lake Chaohu and can therefore serve as indicators of the lake's health and assist in the assessment of OCPs risks to human health. OCP levels in eight species of aquatic biota were measured using GC–MS, and the relationships between the biota and OCP levels in the water and suspended solids were studied. DDTs pose potential human health risks and were the predominant OCP components found in the aquatic biota. DDT had the highest mean bioaccumulation factor (BAF) and biota suspended solids accumulation factor (BSSAF) of all of the studied OCP components. The food web magnification factors (FWMF) for p, p′-DDT were greater than 1, implying that biomagnification occurred. This finding indicates that DDTs still pose a serious threat to the ecosystem and human health in Lake Chaohu, even though the agricultural application of DDT powder has been officially banned since 1983. There were significant positive relationships between OCPs levels in Culter erythropterus and those in both water and suspended solids, as well as between OCPs levels in Protosalanx hyalocranius and those in suspended solids. This finding suggests that C. erythropterus and P. hyalocranius are the most sensitive aquatic biota to OCPs and may serve as the most effective bioindicators for monitoring OCP contamination in the water and suspended solids of Lake Chaohu. Megalobrama amblycephala, which contained the highest wet weight mean OCP concentration, is the most sensitive OCP indicator and can be used to assess the human carcinogenic risk of OCPs in Lake Chaohu.  相似文献   

7.
8.
从线粒体控制区全序列变异看短颌鲚和湖鲚的物种有效性   总被引:32,自引:0,他引:32  
经克隆测序获得我国七丝鲚(Coilia grayii)、凤鲚(C. mystus)、刀鲚(C. nasus)和短颌鲚(C. brachygnathus)以及太湖湖鲚(C. nasus taihuensis)等4个种和1亚种32尾个体的mtDNA D-loop区全序列, 以日本鳀(Engraulis japonicus)和秘鲁鳀(E. ringens)为外类群构建了中国鲚属的分子系统发育树, 并讨论了短颌鲚和湖鲚的物种有效性。结果显示, 七丝鲚的D-loop区全序列长1,208 bp, 凤鲚1,279–1,361 bp, 刀鲚1,252–1,290 bp, 短颌鲚1,214–1,252 bp, 湖鲚1,252–1,442 bp, 除七丝鲚外的其他种类个体间均表现出序列长度的多态性。短颌鲚、刀鲚和湖鲚三者间的平均K 2-P遗传距离仅为0.011–0.020, 明显小于它们与凤鲚、七丝鲚及外类群间的遗传距离(0.051–0.349)。以邻接法和最大简约法构建的系统发育树表明, 刀鲚、短颌鲚及湖鲚均未各自构成单系, 而是共同构成一个单系群, 三者并未发生显著分化。研究表明, 短颌鲚和湖鲚为刀鲚的淡水生态型种群, 并非有效物种。系统发育分析表明, 中国鲚属3个有效物种间以凤鲚最为原始, 刀鲚和七丝鲚为姐妹群, 处于较进化的位置。推测凤鲚可能是鲚属祖先种最早从起源中心扩散到西北太平洋的后裔, 而刀鲚和七丝鲚则是凤鲚在演化过程中分别适应寒冷和温暖气候而分化出的物种。  相似文献   

9.
为调查短颌鲚(Coilia nasus)在三峡库区的资源现状,自2019年7—12月于三峡库区的长江一级支流澎溪河、梅溪河、草堂河、大宁河共采集短颌鲚样本459尾,用以分析三峡库区现有短颌鲚的年龄结构及生长特征.研究结果显示,三峡库区短颌鲚群体由1—6龄组成,1龄即可达性成熟,群体中1—3龄个体占比90.85%;群体平...  相似文献   

10.
基于耳石微化学的长江安徽和县江段刀鲚生境履历重建   总被引:3,自引:0,他引:3  
为了解长江刀鲚(Coilia nasus)的“生境履历”, 利用电子探针微区分析技术研究了2015年5月17日在长江安徽和县江段捕获的刀鲚短颌鲚与长颌鲚类型耳石Sr和Ca微化学特征。短颌鲚的耳石Sr/Ca值变化动态为2类, 一类比值稳定在2.00左右(1.65±0.87—2.03±0.96), 反映了其纯淡水的生境履历; 另一类比值波动显著, 不仅具有对应淡水生境的低值(2.39±1.18—2.63±0.85), 还具有对应半咸水生境的高值(3.22±1.17—3.29±1.14), 显现了其江海生活的生境履历。长颌鲚耳石的Sr/Ca值均波动显著, 同时具有对应淡水生境的低值(1.35±1.07—2.37±1.04)和半咸水、海水生境的高值(3.47±1.09—8.35±1.25), 表现了其均为溯河洄游的生境履历。Sr面分析结果也与上述Sr/Ca值的结果相印证。长江安徽和县江段刀鲚资源组成复杂, 群体可由纯淡水型和江海生活型的个体共同组成。  相似文献   

11.
为探究长江刀鲚生殖洄游过程中脂肪酸组成及其含量变化规律,研究选择洄游距离、卵巢发育和规格大小3个影响因子设置梯度,对长江刀鲚肝胰腺、肌肉和卵巢的脂肪酸组成及含量进行实验分析。实验结果显示, 62尾雌性刀鲚3个组织均检测出28种脂肪酸,以单不饱和脂肪酸(MUFA)含量最高,大于各组织总脂肪酸含量的56.23%,各类脂肪酸中的C18:1、C16:0、C16:1、DHA和EPA含量较高,为主要脂肪酸。在生殖洄游过程中,刀鲚肝胰腺总脂肪含量随洄游距离的延长呈上升趋势,从崇明江段的(526.61±38.50) mg/g增加至安庆江段的(587.21±124.72) mg/g,而肌肉和卵巢总脂肪酸含量呈显著下降趋势,分别下降了33.03%和57.09%(P<0.05)。在各体长组中,肌肉总脂肪酸、SFA、MUFA和PUFA含量与体长呈正相关(P<0.05),而肝胰腺和卵巢总脂肪酸及各类脂肪酸含量与体长无显著相关性(P>0.05)。在卵巢发育过程中,刀鲚肝胰腺和肌肉总脂肪酸、MUFA和PUFA含量随卵巢由Ⅱ期发育至Ⅳ期均呈下降趋势,总脂肪酸含量分别减少了47.56%和22.40%,...  相似文献   

12.
2010—2012年采用刺网(多网目单层刺网和单网目三层刺网)、电捕、底拖网和地笼对上海青草沙水库的鱼类多样性进行了调查.调查共采集到鱼类34种,隶属8目、12科,其中鲤形目鱼类物种数最多(19种)、鲈形目次之(6种).多网目单层刺网仅采集到鱼类19种,其中刀鲚为优势种.聚类分析表明,单层刺网网目规格对渔获物物种组成影响较为显著,网目为2 cm的网片的渔获物优势种为刀鲚和贝氏〖FK(W*8/9。1〗〖PS5号F体.eps,BP#〗〖FK)〗
,其他网目网片优势种为刀鲚.渔获物物种数和单位努力捕获数量均有随着网目规格增大而下降的趋势.网目规格对优势种刀鲚的体长分布影响显著,且随着网目规格的增加而增大.为更加科学合理地评估某水域的鱼类群落多样性,需要结合多种采样方法进行鱼类调查.  相似文献   

13.
Length–weight relationships were estimated for two fishes [Lepidotrigla alata (Houttuyn, 1782), Sirembo imberbis (Temminck & Schlegel, 1846)] from the estuary of the Pearl River. All fish specimens were collected seasonally with commercial trawls (5 cm main trawl and 5 cm codend mesh) from March 2013 to July 2015. The b values were calculated as 3.03 for Lepidotrigla alata and 3.38 for Sirembo imberbis.  相似文献   

14.
Presented are the relationships between total length and weight, and between total length and standard length for six commercial fishes collected twice a month from local fish markets in southern Korea between 2005–2006 for Acanthopagrus schlegelii (Bleeker, 1854), Hexagrammos agrammus (Temminck & Schlegel, 1843) and Hexagrammos otakii (Jordan & Starks, 1895), and monthly in 2004 for Dentex tumifrons (Temminck & Schlegel, 1843), Doederleinia berycoides (Hilgendorf, 1879) and Scomberomorus niphonius (Cuvier, 1832). The LWR for D. tumifrons is estimated for the first time, and a new maximum length was recorded for S. niphonius. All total length and weight relationships were significant (all r2 > .953). The values of exponent b, estimated using simple linear least squares of log‐transformed weight and length data, ranged from 2.945 to 3.317.  相似文献   

15.
利用电子探针微区分析(EPMA)技术, 分析了2018年8月采自湖南省岳阳市洞庭湖畔水产市场2尾刀鲚(Coilia nasus)干制个体的矢耳石中锶和钙微化学特征。定量线分析结果显示, 2尾样本的耳石锶钙比值(Sr/Ca×1000)波动显著, 从耳石核心到边缘可分别出现对应淡水生境的锶钙比值<3的低值区, 对应于半咸水生境的3—7高值区和再次为对应于淡水生境<3的低值区。面分布分析结果更直观显示两尾刀鲚个体的耳石从核心到边缘对应于不同盐度生境的锶含量变化图谱, 即从耳石核心到边缘可分别出现对应于淡水生境的蓝色区域, 对应长江口外半咸水生境的黄绿色区域和再次对应于淡水生境的蓝色区域。这种淡水-半咸水-淡水的生境转换显示出了上述个体的典型溯河洄游生活史“履历”。研究显示目前距长江河口约1400 km的洞庭湖中仍可能存在溯河洄游型刀鲚个体。  相似文献   

16.
为理清刀鲚(Coilia nasus)洄游时间与体内寄生线虫的关系,于2018年4—7月在长江安庆段调查了刀鲚寄生线虫的感染情况及群落结构。结果显示,刀鲚线虫感染率为96.0%,平均感染强度为8.06±7.26,平均感染丰度为7.74±7.29。经ITS分子标记共鉴定出7种线虫,其中异尖属2种,宫脂属4种,针晶蛔属1种,均为海水性寄生虫,可作为刀鲚有海水生活经历的生物标记。其中派氏异尖线虫(Anisakis pegreffii)的感染率最高,为84.5%,其次为内弯宫脂线虫(Hysterothylacium aduncum)(31.0%),二者的感染强度和感染丰度也较高,其中平均感染强度分别为6.40±6.08和2.81±2.49,平均感染丰度分别为5.41±6.05和0.87±1.90;派氏异尖线虫感染丰度和感染强度在洄游早期呈上升趋势,到6月下旬稍有降低但不显著(P>0.05),内弯宫脂线虫感染丰度和强度则均表现为下降趋势。刀鲚寄生线虫的群落结构在不同洄游时间也有所差异,其中刀鲚感染线虫的平均物种丰富度和Brillouin多样性指数均呈下降趋势,但优势物种一直是派氏异尖线虫,...  相似文献   

17.
Given the scarcity of information suitable for other forms of fish stock assessments, the growth, and mortality of 10 important marine exploited fishes in China's coastal seas were estimated, based on published length‐frequency data and the ELEFAN approach and software. The resulting parameters, complemented with growth curves from FishBase were then used for yield‐per‐recruit analyses. These 10 species were both traditional commercial species (Trichiurus lepturus, Larimichthys polyactis, Scomber japonicus) and less commercial interest species (Coilia nasus, Engraulis japonicus, Decapterus maruadsi, Psenopsis anomala, Coilia mystus, Setipinna tenuifilis, Harpadon nehereus). The yield‐per‐recruit analyses indicated that the fishing mortality experienced by these 10 fish species was very high, especially in view of the extremely small cod‐end mesh sizes deployed by Chinese trawlers, of about 10 mm or less (vs. 25 mm as minimum legal size). More precisely, all 10 species suffered from growth overfishing, which was very pronounced in large species. Indeed, enlarging cod‐end mesh size, by increasing mean sizes at first capture, would increase yield‐per‐recruit for all 10 fish species by a factor of up to 2.5. Obviously, such increases in mesh size would have to be in tandem with other management measures designed to ensure the sustainability of China's marine fisheries resources.  相似文献   

18.
为摸清上海黄浦江5条骨干人工河流开挖半个世纪以来形成的鱼类物种资源家底,文章于2021年6月(夏季)和11月(秋季)用刺网对20个断面作了采集,获得鱼类标本13379尾,经鉴定有60种,隶属于8目17科45属。其中,鲤形目有2科28属41种,鲈形目7科8属8种;洄游鱼类2种,河口鱼类8种,其余均为淡水鱼类。IRI≥1000的优势种合计有9种,刀鲚(Coilia nasus)是5条河流共有的优势种。ABC曲线反映除金汇港外,其他河流总体上以中小型鱼类为主体,鱼类群落受到了严重干扰。βc指数和βr指数均反映浦东川杨河与大治河之间的鱼类组成相异性最大,浦南金汇港与龙泉港之间的鱼类组成相异性最小。20个断面可分为3组, D1和Z2断面为组Ⅰ,金汇港、龙泉港和除Z2断面的大治河为组Ⅱ,川杨河和除D1断面的淀浦河为组Ⅲ,似鳊(Pseudobrama simoni)、刀鲚、鲫(Carassius auratus)和?(Hemiculter leucisculus)是造成组间鱼类群落结构差异性的主要分歧种。研究认为,这5条人工骨干支流保存了比黄浦江源头、干流...  相似文献   

19.
The length‐weight relationships (LWRs) are presented for seven freshwater fish species (Odontobutis potamophila, Protosalanx chinensis, Acheilognathus chankaensis, Megalobrama skolkovii, Pelteobagrus vachelli, Macropodus chinensis, Pseudobrama simoni) from JiangSu province in China. A total of 1340 specimens were sampled and measured between August 2012 and September 2013. No information regarding the LWRs of these species was available in FishBase.  相似文献   

20.
The role of Chironomidae in energy flow of a lotic ecosystem   总被引:1,自引:0,他引:1  
Chironomid secondary production was estimated on a species-specific basis for 14 dominant taxa in a third-order woodland stream. Results from this study were used to provide an expalanation for the common observation that benthos secondary production in streams is insufficient to account for levels of fish production,i.e., the ALLEN paradox. Annual chironomid secondary production was 29.7 g dry mass m–2 and accounted for 80% of the total aquatic insect secondary production. A contribution by chironomids this high has not been reported previously from similar streams and indicates that chironomids are an energetically important group available for fish consumption. Most studies examining chironomid secondary production group all taxa at the family level and calculate secondary production for the entire family using the size-frequency method. This approach violates assumptions of the size-frequency method and will result in inaccurate and unpredictable estimates of chironomid secondary production. The species-specific approach to estimate chironomid production used in this study, combined with non-chironomid production, yielded a benthos annual production rate that exceeded consumption necessary to support fish production.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号