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1.
为了解和评估胶州湾内菲律宾蛤仔的季节分布和资源状况,于2014年2月(冬季)、5月(春季)、8月(夏季)和11月(冬季)对胶州湾菲律宾蛤仔的季节分布情况与生物资源量进行了全面调查和评估,分析了胶州湾菲律宾蛤仔的壳长、生物量、栖息密度和年龄组成。结果显示,胶州湾2014年的年均栖息密度为409.6ind./m~2,最高栖息密度达2 377.5ind./m~2;年均生物量为625.5g/m~2,最高生物量高达3 445.3g/m~2。胶州湾全年菲律宾蛤仔的年龄组成主要是1、2和3龄蛤,而其中的1和2龄蛤占有明显数量优势。胶州湾菲律宾蛤仔种群年龄结构出现低龄化,1龄蛤占绝对优势,2龄蛤仅次于1龄蛤,3龄以上最少。若以壳长30mm的蛤仔为采捕规格,2014年胶州湾菲律宾蛤仔的年均商品率为6.8%;若以壳长25mm蛤仔为采捕规格,2014年胶州湾菲律宾蛤仔的年均商品率为33.2%。从菲律宾蛤仔的生物量、年龄结构和商品率综合分析,2龄蛤可作为优势的采捕年龄,5月是最佳的采捕时期。  相似文献   

2.
2003年6月,利用模拟现场流水系统采用生物沉积法对胶州湾养殖的菲律宾蛤仔的清滤率、摄食率、吸收效率及其与蛤仔规格之间的关系进行了现场实验研究。结果表明,个体的清滤率在0.18—0.40L/h范围内,平均为0.31L/h(SD=0.068),个体清滤率和摄食率随壳长增加而增加,但吸收效率与个体大小无关。蛤仔对颗粒有机物(POM)、颗粒有机碳(POC)、颗粒有机氮(PON)及叶绿素的吸收效率不同,对叶绿素的吸收效率最高,平均为(81.8±7.9)%,对POM、POC和PON的吸收效率分别平均为(64.2±10.7)%(、55.7±9.8)%和(53.9±9.6)%。结合胶州湾蛤仔的生物量和野外调查数据,分析了春季养殖蛤仔对胶州湾初级生产力和颗粒有机碳的摄食压力及可能对整个湾的物质循环的影响。根据本文的结果估算,菲律宾蛤仔对本实验海区初级生产力和颗粒有机碳现存量的摄食压力分别为560%和90%。养殖的蛤仔通过滤食已经能够影响甚至控制养殖区的浮游植物的生长或初级生产力,甚至与整个胶州湾叶绿素a浓度的季节性变化趋势相吻合,因为胶州湾叶绿素浓度冬、夏季高,春、秋季节低,而蛤仔的生长旺季刚好在春、秋两季。  相似文献   

3.
采用光滑河蓝蛤和菲律宾蛤仔两种双壳贝类培养长蛸幼体,分析其生长和存活情况。结果显示,长蛸初孵幼体无外卵黄,体表光滑,第一对腕(最长腕)约为胴长的2.9倍,腕吸盘两列,第1—4对腕平均吸盘数(n=3)分别为66±4.60、55±3.76、43±4.59和41±3.82;1—15d幼体投喂的是光滑河蓝蛤(壳长15.4—20.3mm),之后投喂菲律宾蛤仔(壳长33.2—39.3mm);幼体30d—70d总成活率由80.99%降至54.65%;整个培育过程中,幼体生长率与饵料效率呈极显著线性回归关系(P0.01),y=1.452x-2.731(R2=0.865);1—80d胴长/全长比增幅高于腕长/全长,表明胴体增长快于腕的增长;各腕吸盘数变化不显著;幼体鲜重与培养天数呈指数函数关系,Wt=0.301e0.010t(R2=0.854,P0.01);长蛸幼体最终生长率为122.05%,平均生长率为9.97%/10d。  相似文献   

4.
山东蓬莱菲律宾蛤仔资源调查研究   总被引:1,自引:0,他引:1  
对蓬莱沿海的菲律宾蛤仔资源进行了调查研究,分析了菲律宾蛤仔的分布、资源现状及其生物学特性。结果表明:蓬莱沿海菲律宾蛤仔主要分布于栾家口、湾子口、刘家旺、朱家庄滩;资源总面积146.9hm2,资源现存量58.9t,可捕量26.8t,宜捕量16.1t,商品率18.1%;平均壳长与体重的关系方程:W=0.19458 L3.2782(r=0.88);每年2次繁殖高峰,分别为6月和10月。  相似文献   

5.
环境因子对菲律宾蛤仔摄食生理生态的影响   总被引:18,自引:1,他引:17  
董波  薛钦昭  李军 《海洋与湖沼》2000,31(6):636-642
于 1 998年 1— 6月 ,在中国科学院海洋研究所实验室内采用静水方法对采自胶州湾潮间带的菲律宾蛤仔 (以下简称蛤仔 )进行摄食率、清滤率和吸收率的测定。结果表明 :(1 )蛤仔摄食率和清滤率随着个体体重的增加而增大 ,而单位重量的摄食率和清滤率随个体体重的增加而减小 ,它们之间呈幂函数关系。 (2 )底质对蛤仔摄食生理影响的实验表明 :铺砂可以显著地提高蛤仔的摄食生理指标。 (3)在一定的饵料浓度范围内 ,摄食率和清滤率随着浓度的增加而增大 ,呈幂函数关系。当饵料浓度达到一定值后 ,清滤率迅速下降 ,而摄食率只略微有所下降 ,基本上保持平稳不变。这说明蛤仔可以通过调节清滤率来稳定摄食率。 (4)蛤仔吸收率和饵料浓度及个体大小无明显相关性。 (5)水温 1 5℃ ,投喂小球藻的条件下 ,实验结果显示蛤仔 [壳长 (3.53± 0 .0 2 )cm、软体部干重 (0 .41± 0 .0 2 )g]产生假粪的阈值为2 .1 6mgPOM /L。  相似文献   

6.
养殖远海梭子蟹的形态学变化观察   总被引:1,自引:0,他引:1  
在温度29.5±1℃和盐度30条件下,将远海梭子蟹1期龄幼蟹人工养殖成15期龄蟹.结果表明:198.1d蟹蜕壳14次,成活率为10.8%;蟹平均蜕壳时间间隔从2.6d逐渐延长至32d;平均体重从0.003g增至67.324g,平均体重增长率为61.8%~170%,蜕壳增长率随着幼蟹发育而下降,但蜕壳体重绝对增长量随着幼蟹发育而增加.平均甲长从1.75mm增至45.87mm;平均甲宽从2.28mm增至81.79mm.各发育期甲宽、甲长比为1.30~1.86.甲宽和甲长与体重呈指数关系,甲宽(y)与体重(x)关系式为y=2.244 6e0.252 7x;甲长(y)与体重(x)关系式为y=1.603 8e0.231 5x;甲长(y)与甲宽(x)呈线性关系,关系式为y=1.805x.  相似文献   

7.
菲律宾蛤仔(Ruditapesphilippinarum)是重要的海洋经济贝类和海水养殖品种,具有较强的表型可塑性特点,不同地理群体之间存在表型差异。本研究根据实测数据建立了胶州湾与天鹅湖菲律宾蛤仔壳长(SL)与壳高(SH)、壳宽(SW)和活体重(W)的回归方程,定量分析了两个地理群体的形态学差异。由于其近似圆形的形态使得所能测量的外部指标较少,限制了传统形态测量学在其地理群体判别中的应用。本研究提出了将传统形态测量学和广义线性模型(GLM)相结合的方法,建立了判别菲律宾蛤仔地理群体的逻辑斯蒂(Logistic)回归方程。结果表明:菲律宾蛤仔的天鹅湖群体比胶州湾群体具有更高的SH/SL和SW/SL比值,壳形椭圆较圆且隆起程度高,"凸"形明显;基于GLM模型的Logistic回归能够快速准确地判别菲律宾蛤仔的地理群体归属,判别正确率高达94.23%。本研究为双壳类物种地理群体判别提供了新的分析方法和技术手段。  相似文献   

8.
于2006年2月、5月、8月和11月四个季度月采用呼吸瓶法现场研究了胶州湾菲律宾蛤仔的呼吸排泄作用。结果表明,胶州湾菲律宾蛤仔呼吸排泄速率具有明显的季节变化趋势,春、夏季高于秋、冬季。不同生物学规格的蛤仔呼吸排泄速率具有明显的差异,单位个体耗氧率、排氨率和排磷率均随着个体大小的增加而增加,而单位体重的耗氧率、排氨率和排...  相似文献   

9.
等边浅蛤Gomphina veneriformis的群体组成与生长   总被引:4,自引:0,他引:4  
本文据1987年12月至1988年12月逐月在舟山朱家尖岛沙滩采集的标本进行研究,结果表明,等边浅蛤Gomphina veneriformis壳宽、壳高和体重的生长,完全可以壳长表示;其补充群体出现于8月份,各年龄组在4~10月生长较快;肥满度和鲜出肉率在7~8月达最高值;6~9月是采捕期,但又是繁殖期,建议适量采捕或划出禁采区,以利保护资源。  相似文献   

10.
为探究菲律宾蛤仔(Ruditapes philippinarum)筏式养殖模式可行性,在我国黄海北部首次开展了菲律宾蛤仔"斑马蛤2号"新品种的筏式与底播养殖模式对比试验。采用平均壳长为2.37 cm,平均全湿重为2.99 g规格的"斑马蛤2号"苗种为试验材料,对两种养殖方式的"斑马蛤2号"生长、存活、营养成分进行比较分析,结果表明,筏式养殖"斑马蛤2号"夏季(4-7月)壳长、壳宽、壳高、全湿重、软体重的相对生长速率分别比底播养殖"斑马蛤2号"快149.54%、100.61%、116.30%、152.25%、132.58%(P<0.05)。筏式养殖"斑马蛤2号"存活率为90%以上,显著高于底播养殖(P<0.05)。两种养殖方式的"斑马蛤2号"水分、灰分、粗蛋白、糖原、脂肪酸等营养成分季节变化规律基本一致。筏式养殖"斑马蛤2号"冬季糖原、单不饱和脂肪酸含量明显高于底播养殖"斑马蛤2号"(P<0.05)。研究表明,当年10月采用多层聚乙烯网笼按密度为150-200粒/层放养菲律宾蛤仔"斑马蛤2号"大规格苗种(平均壳长为2.37 cm,平均全湿重为2.99 g),可于翌年的4月、7月、10月收获平均壳长为3.03、3.36、3.51 cm的市场规格产品。筏式养殖模式具有存活率高的优点。"斑马蛤2号"筏式养殖模式试验的成功为蛤仔健康养殖提供了新途径。  相似文献   

11.
缢蛏(Sinonovacula constricta)是我国重要的水产经济贝类,开展耐高盐新品种选育对平衡不同地区缢蛏良种养殖意义重大。本研究对不同家系缢蛏幼贝进行高盐胁迫,运用统计学方法和相关性分析探究了缢蛏耐高盐性能及其与生长性状的相关性。结果显示,缢蛏家系间壳长、壳高、壳宽和体质量表型值差异较大,体质量变异系数达15.53%。不同家系对高盐耐受性差异较大,家系间死亡率范围在0~100%。胁迫实验共持续9d,各家系缢蛏首粒死亡时间在第1~9d之间,而且死亡率较高的家系内缢蛏死亡时间离散程度较大,说明不同个体间高盐耐受性差异也较大。缢蛏开始出现大量死亡的时间主要在胁迫后第8d,第9d部分家系死亡率高于80%,说明缢蛏对高盐耐受存在一个阈值,超过该阈值会开始或大量死亡。皮尔逊和斯皮尔曼相关性分析显示,缢蛏存活时间和生长性状为正相关,其中存活时间与缢蛏壳长、体质量相关性均达到显著水平(P<0.05)。缢蛏存活率与体质量、生长速度均显著正相关(P<0.05)。整体而言,壳长较长和体质量较重的缢蛏个体耐高盐性能较强,在高盐环境中具有生长优势。本研究揭示了缢蛏的高盐耐受性及其与生长性状的相关性,为缢蛏耐高盐选育工作提供了重要的参考依据。  相似文献   

12.
The surf clam Mesodesma donacium is an economically important species for Chilean and Peruvian shellfisheries. This clam is often infested by Polydora bioccipitalis, a species belonging to the Spionidae, the most common parasitic polychaete group. To study this association, clams were sampled monthly over a one-year period in northern Chile. Collected clams covered the entire available size range and were classified into four infestation levels in order to study: (1) the relationship between prevalence of infestation (PI) and host size, (2) the temporal pattern of infestation events related to seasonal temperature changes, and (3) the relationship between infestation, body condition index (BCI) and gonado-somatic index (GSI). Additionally, growth rate and digging ability of clams with different infestation levels was studied. A logistic regression model best explained the relationship between PI and host size, with the smallest infested clam being 34 mm long and PI increasing steeply thereafter. Ontogenetic shifts in the habitat of the clam and ontogenetic changes, mainly in shell morphology, seem to explain the sigmoid pattern. Periods of increased shell blistering after infestation by P. bioccipitalis showed a similar seasonal pattern with GSI and BCI of non-infested clams, suggesting either an association between infestation ability and low condition of the clam or common environmental triggers for those factors. Heavily infested clams showed a significant lower BCI, growth rate and digging ability; however, given its low number, they are unlikely to be significant in terms of the local population survival. However, the infestation could play a key role in explaining mass mortality of northern populations during El Niño events, given the latitudinal differences in PI and the fact that infestation ability could be enhanced by increased temperature and facilitated in stressed clams.  相似文献   

13.
Pathologic condition of Manila clam, Ruditapes philippinarum collected from Haeju off the west coast of North Korea in February and March 2007 was investigated in this study. The diagnostics included a protozoan parasite, Perkinsus olseni, the brown ring disease (BRD) caused by bacteria Vibrio tapetis and metazoan parasites Trematod and Cestod. P. olseni infection was examined using histology and Ray’s fluid thioglycollate medium (RFTM) assay along with Choi’s NaOH digestion technique. Trematode and cestode infection was also examined from the histology. A total of 140 clams with 35–45 mm in shell length (2–3 years old) were analyzed. Condition factor (CF), a ratio of the wet tissue weight to the shell dry weight, ranged from 0.445±0.074 (February) to 0.544±0.132 (March). Total body burden of P. olseni (i.e. infection intensity) ranged from 18,644±37,755 (February) to 26,933±80,611 cells/g wet tissue (March) with the prevalence of 76.7–43.3% (March) respectively. Prevalence of trematode and cestode infection in February and March varied 22.5–25.0 and 15.0–22.5% respectively. Infection intensity of V. tapetis ranged 1–2 and the prevalence was 1.4 (February) and 5.7% (March). Prevalence and infection intensity of P. olseni in clams from Haeju was comparatively lower than those of clams reported on the west coast of Korea. BRD and the other metazoan parasite infection were also relatively lower or similar to the condition of the clams reported previously. CF of Haeju clams was also relatively higher than the clams in Gyeonggi Bay and Taean, suggesting that Haeju clams had relatively better pathologic and health condition.  相似文献   

14.
A breeding-selection program for the clam,Meretrix meretrix,was conducted since 2004.Two of the selection populations were generated with the shell color pattern as an additional selection criterion and named as SP(purple stripes)population and SB(black dots)population.The third-generation SP and SB populations(08G3SP and 08G3SB,respectively)were cultured at two commercial clam farms and a nursery pond and their shell lengths were compared.08G3SB clams had significantly larger sizes than 08G3SP clams at commercial clam farms(p<0.05),yet 08G3SB individuals were significantly smaller than 08G3SP individuals at the nursery pond(p<0.05).Then,we examined the growth of the fourth-generation SP and SB populations(10G4SP and 10G4SB,respectively)at a commercial farm,and found that the shell lengths of the 10G4SB clams increased at a significantly higher growth rate than the 10G4SP clams(p<0.05)from May to September,when the water temperature was between 24.2–27.5 C,while 10G4SB lost the growth advantage in the other months.These results indicated that SP and SB populations responded differently to environmental factors,so it is beneficial for the clam farmers to select a suitable population according to the culture environment.Furthermore,a diallel mating of the SB and SP populations was designed to investigate whether their hybrid population would show heterosis.However,the heterosis was not shown in this study,which might result from the slight genetic divergence between SB and SP populations.  相似文献   

15.
番红砗磲Tridacna crocea Lamarck由D形幼虫发育至幼苗(第26天),壳长净生长106.62μm,壳高净生长104.41μm。其生长过程可分为三个时期:面盘期幼虫生长快,壳高的增长大于壳长的增长;变态期幼虫生长平缓,壳长与壳高的增长接近均衡;两者之间的足面盘过渡期幼虫生长出现两个停滞期。壳长与壳高的关系可以H=0.99998L-21.81275表示,它们分别与铰合部长度的变化有联系。壳长/壳高和(1/2)壳高/铰合部长度两个比率呈现一定的规律性,并可预测幼虫足的发生。  相似文献   

16.
Seagrass seed bank plays a key role in the regeneration of new vegetation when seagrasses are removed by the natural or man-made disaster. Various factors may affect the development of sediment seed bank. We conducted a microcosm experiment to test the effects of burrowing and feeding activities of Manila clam, Ruditapes philippinarum on the burial of Zostera marina seeds in sediments. The effects of lasting time (3-hour, 1-day, 3-day, 7-day, 14-day and 28-day), clam density (0, 2, 4 and 8 clams with shell length of 3 cm in each microcosm) and clam size (shell length of 2, 3 and 4 cm at 4-clam density) on seed burial were examined in plastic microcosm cores (30 cm high × 10 in inner diameter) in a 28-day period. Results showed that the seed burial depth significantly increased with time, the density and the size of clams. No seeds were buried in the sediment in the cores without clams during the whole experiment period. For the 3-cm clams, about 91.61% of the seeds were buried in the sediment at the end of the experiment in the high-density treatment (8 clams at each core); while in the medium and low-density treatments (4 and 2 clams in each core, respectively), about 76.93% and 60.61% of the seeds were buried in the sediment, respectively. For the size treatments, large (4 cm) clams buried 89.56% of the seeds at the end of the experiment, much more than those of medium (3 cm, 76.93%) and small (2 cm, 61.50%) size clams. During the whole experiment period, nearly all of the buried seeds were at a depth of from 0 cm to 5 cm. These results suggested that Manila clam Ruditapes philippinarum may play an important positive role in seagrass seed bank dynamics in the field.  相似文献   

17.
红壳色文蛤选育子代各壳色的形态分化及养殖效果的比较   总被引:2,自引:0,他引:2  
以红壳色为目标性状,于2009年进行了文蛤(Meretrix meretrix)的群体选育研究,建立了红壳色选系子一代(Fl),对子一代壳色种类、分布频率及其数量性状进行了统计、测量和分析,并对各壳色的形态、生长速度做了研究.结果表明,文蛤壳色具有多态性,红色、黄色、白双、黄双、波纹的分布频率分别为75.58%、8.55%、0.53%、14.83%、0.50%.红壳色亲本的子代中出现红色∶花色=3∶1,符合孟德尔遗传模式.聚类分析与欧氏距离矩阵结果表明,文蛤波纹与黄色遗传距离最近,白双与黄双遗传距离相近,与红壳色的遗传距离最远.主成分分析显示白双文蛤与黄双文蛤在空间分布上相对重叠,波纹文蛤与黄色文蛤具有较高的重叠率,而红壳色文蛤相对分散,从而进一步说明5种壳色文蛤的遗传距离关系.经过1a同池养殖,子代壳长多数已达到10~30 mm,红壳色文蛤的日生长率为0.20%,花壳色文蛤的日生长率为0.18%,且红壳色文蛤的相对比较生长速度比花壳色文蛤快10.41%.红壳色文蛤选育子代的壳长与壳宽、壳高、粒重存在一定的回归关系.红壳色文蛤壳长对壳宽、壳高、粒重的回归方程分别为:y1=0.502 4x1-0.556 0(R2=0.992 0)、y3=0.8103x3+0.620 0(R2=0.995 6)、y5=0.000 3x25.9029(R2=0.991 9),花壳色文蛤壳长对壳宽、壳高、粒重的回归方程分别为:y2=0.495 3x2-0.419 2(R2=0.990 9)、y4=0.798 5x4+0.793 5(R2=0.995 6)、y6=0.000 4x26.845 8(R2=0.993 4).研究结果为文蛤的红壳色定向选育奠定了理论基础.  相似文献   

18.
为了解TYR基因与蛤仔免疫的关系,本实验利用荧光定量PCR技术研究了菲律宾蛤仔五个群体(白蛤、白斑马蛤、斑马蛤、养殖和野生群体)的鳃组织和肝胰腺组织在LPS胁迫下TYR基因在不同时间(0 h、3 h、12 h、24 h、48 h)的表达特性。结果表明,在LPS注射后鳃组织中TYR6基因表达水平在白蛤和白斑马蛤3 h、6 h、12 h,野生蛤仔3 h,斑马蛤3 h、6 h,养殖群体6 h、12 h显著上调(P0.05),3h野生蛤仔和斑马蛤达到峰值, 6 h白蛤、白斑马蛤、养殖群体达到峰值(P0.05);在肝胰腺中,养殖群体和白斑马蛤6 h,白蛤6 h、24 h,野生群体24 h,斑马蛤3 h显著上调, 3 h野生蛤仔和斑马蛤达到峰值,6h养殖群体、白蛤、白斑马达到峰值(P0.05);鳃组织中TYR10基因表达水平在白蛤、野生群体和白斑马蛤3 h,养殖群体3 h、6 h,斑马蛤3 h、12 h显著上调(P0.05),肝胰腺组织中TYR10基因表达水平在白蛤3 h,野生群体3 h、6 h、12 h,斑马蛤、养殖群体6 h显著上调(P0.05),推测TYR基因在五个菲律宾蛤仔群体的鳃和肝胰腺中参与了免疫应答。通过对TYR基因的氨基酸序列进行二级结构分析和系统发育树分析,找到两个铜离子结合位点和6个组氨酸残基,并发现TYR6基因和长牡蛎同源性最高,为39.43%, TYR10基因和大珠母贝同源性最高,为51.04%。本文首次探讨在LPS胁迫下菲律宾蛤仔TYR基因的表达特性,为进一步探究TYR基因与菲律宾蛤仔免疫应答机制提供参考。  相似文献   

19.
Moon snail predation on clams is a common model system of predator–prey interactions. In this system, the predator bores through the shell of its prey, leaving a distinct and identifiable hole. Some paleoecological and behavioral research on moon snails suggests a trend in predation preference directed toward clams with small shells. Rarely, however, have studies tested relative drilling frequencies across species and size ranges in natural assemblages of clam communities. We examined the clam community composition at two beaches in South Carolina, USA, and we then tested moon snail predator preferences for (a) clam prey species and (b) whether their selection is related to prey shell size. We collected a total of 1,879 clam shells, identified each shell to species and recorded their anteroposterior length. The species composition of clams differed significantly between the two beaches; Anadara ovalis was dominant at both sites, but three of ten total species were only collected at one beach. Folly Beach had nearly a 60% higher the overall drilling frequency (34.6%) versus Edisto Beach (21.8%), and this may be linked to the differences in clam community compositions at the sites. For A. ovalis and Mulinia lateralis, shells with larger lengths have lower probabilities of being bored by a moon snail. Anadara brasiliana, which generally is a thinner‐shelled clam species, had the highest total drilling frequency (77.2%), and Noetia ponderosa, a thicker‐shelled clam, had a considerably lower drilling frequency (12.0%). We conclude that both community level factors (species composition) and population characteristics (shell size distributions) may influence the local drilling frequency by moon snails.  相似文献   

20.
波纹巴非蛤胚胎与浮游幼虫的形态发育和生长特性   总被引:1,自引:0,他引:1  
摘要:在人工繁育条件下,在显微镜下对波纹巴非蛤胚胎与浮游幼虫的形态进行活体观察和拍摄,并用内置目微尺进行壳长和壳高的测量.首次报道了波纹巴非蛤胚胎与浮游幼虫的形态发育和生长特点,利用图版和文字描述了波纹巴非蛤早期生活史的形态并对其发育生长特点进行初步探讨.波纹巴非蛤的早期形态体现了浅海性种类的特点,“D”形幼虫期的壳长为90.37±1.53I,zm,壳高为71.86±1.09μm;壳顶后期壳长为130.17±1,83μm,壳高为110.24±1.39μm,与其他帘蛤科种类相比明显较小.  相似文献   

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