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1.
2017年7月~2019年4月期间,本研究采用大面观测、现场模拟实验与生长情况跟踪相结合的手段,基于Dame指标和Herman模型估算了胶州湾菲律宾蛤仔(Ruditapes philippinarum)的养殖容量。结果显示,调查期间,胶州湾水体的叶绿素a浓度为2.09~4.28 mg/m3,均值为3.07 mg/m3;不同规格(壳长2.29~3.59 cm)的菲律宾蛤仔单位个体的平均滤水率为0.45 L/(h?ind.),单位重量菲律宾蛤仔的平均滤水率为2.52 L/(g?h);菲律宾蛤仔1龄、2龄和3龄的平均干重分别为0.18、0.30和0.42 g;胶州湾的水团停留时间为52 d,初级生产时间为1.58 d,贝类滤水时间为2.09 d;1龄、2龄和3龄蛤仔的养殖容量分别为637、378和272 ind./m2。目前,菲律宾蛤仔养殖量已超过养殖容量,建议若以2龄蛤为采捕对象,适宜的播苗密度为582 ind./m2;若以3龄蛤为采捕对象,适宜的播苗密度为789 ind./m2。本研究结果可为保障胶州湾菲律宾蛤仔养殖产业的绿色高质量发展提供理论依据和数据支撑。  相似文献   

2.
以大连獐子岛野生菲律宾蛤仔为材料,对"壳宽型"、"壳扁型"蛤仔两个壳型的壳长、壳宽、壳高、活体质量、软体质量、产卵量及其子代的生长和存活进行比较。试验结果表明,相同壳长的两种壳型蛤仔,"壳宽型"蛤仔的活体质量及软体质量均显著高于"壳扁型"蛤仔(P0.05);两种壳型蛤仔的壳宽均是影响活体质量的主要因素,壳长均是影响软体质量的主要因素;两种壳型蛤仔初孵D形幼虫、3日龄、6日龄幼虫壳长生长差异不显著(P0.05);15日龄"壳扁型"蛤仔幼虫壳长生长显著快于"壳宽型"蛤仔(P0.05);稚贝期,除30日龄外,"壳宽型"蛤仔壳长生长显著快于"壳扁型"蛤仔(P0.05);"壳宽型"蛤仔幼虫及稚贝期存活率均显著高于"壳扁型"品系(P0.05)。  相似文献   

3.
养殖容量评估是衡量贝类养殖活动是否环境友好、碳汇功能能否充分发挥的重要前提。本研究基于2018年5月—2019年2月的走航观测和定点连续观测数据,通过构建营养盐–浮游植物–浮游动物–碎屑–菲律宾蛤仔(nutrients–photoplankton–zooplankton–detritus–clams, NPZD-C)生态系统动力学模型,动态评估了胶州湾菲律宾蛤仔(Ruditapes philippinarum)的养殖容量。结果显示,构建的生态系统动力学模型能够较好地反演菲律宾蛤仔的生长和浮游植物的动态响应,菲律宾蛤仔和浮游植物的实测值和模拟值均呈显著线性相关(P<0.01),R2分别为0.934 8和0.926 4;不同放苗密度情境下的产量模拟结果显示,当苗种(2000~3000 ind./kg)的初始放苗密度分别为300、500、700、1000、1500 ind./m2时,蛤仔的预测产量分别为10.5、15.6、18.9、21.6、23.2 t/hm2;养殖容量评估结果显示,若在期望的10个月养殖时间内收获湿重为5 g以上的商品蛤仔,放苗密度需控制在1000 ind./m2以内,以生态效益和经济效益的最大化为判定标准,适宜的放苗密度为550~750 ind./m2。研究结果可为实施生态系统水平的胶州湾菲律宾蛤仔养殖管理、充分发挥菲律宾蛤仔的碳汇功能提供理论依据和科学指导。  相似文献   

4.
菲律宾蛤仔稚贝最适生长环境条件的响应面法分析   总被引:1,自引:0,他引:1  
为考察温度(T)、盐度(S)、pH及三者交互作用对菲律宾蛤仔稚贝期壳长生长的影响,使用Design-Expert 7.0软件采用BBD(Box-Behnken Design)实验设计方案,进行响应面分析,寻找最适生长条件组合,并构造蛤仔稚贝壳长生长模型。实验进行30 d对蛤仔稚贝壳长(L)进行测量。实验条件梯度设计为温度(30℃、25℃、20℃)、盐度(15、20、25)、pH[(7.00±0.09)、(8.00±0.09)、(9.00±0.09)]。结果显示:(1)温度在实验区间内与蛤仔稚贝壳长生长呈一定的正相关,在30℃附近达到壳长极值,盐度在实验区间内也与壳长生长呈一定正相关,但在接近25时达到壳长极值,pH在8~9时出现壳长极值,略偏碱性水体有利于蛤仔稚贝生长。(2)温度、盐度及pH三者间对蛤仔稚贝生长无显著交互作用(P>0.05)。通过Design-Expert 7.0软件对数据进行二次多元回归拟合,得到蛤仔稚贝壳长Y对编码自变量A、B和C的二次多元回归方程:Y=4.08+0.10A+0.18B+0.11C-0.055A2-0.13B2-0.12C2(R2=0.977 4),软件模拟最适蛤仔稚贝生长的条件组合为[T=29.65℃,S=23.35,pH=(8.46±0.09)]。  相似文献   

5.
不同地理群体菲律宾蛤仔表型性状的相关性与通径分析   总被引:1,自引:0,他引:1  
随机选取繁殖时期的南方群体北方养殖菲律宾蛤仔(SN)、北方土著品种(NN)和南方群体南方养殖蛤仔(SS),测量其壳长(SL)、壳高(SH)、壳宽(SW)、活体质量(mL)、软体质量(mM)和烘干后软体部干质量(mF),采用相关与通径分析方法分析不同地理群体的菲律宾蛤仔表型性状对软体质量的作用效果,为菲律宾蛤仔的选择育种提供理论依据和测度指标。试验结果表明,不同地理群体菲律宾蛤仔的形态学指标无显著差异(P>0.05);不同地理群体各数量性状之间的相关关系均达到极显著水平(P<0.01);决定系数分析表明,不同地理群体菲律宾蛤仔影响软体质量的主要表型性状并不相同,南方群体北方养殖蛤仔群体的壳宽直接作用最大,壳宽通过壳高的间接作用是次要因素;北方土著品种群体壳长是主要因素,壳长通过壳高的间接作用是次要因素;南方群体南方养殖蛤仔群体壳高的直接作用是主要因素,壳长通过壳高的间接作用是次要因素。对通径系数检验不显著的自变量进行删除,利用逐步回归的方法,建立不同地理群体菲律宾蛤仔软体质量的最优回归方程:SN群体,mM1=-4.276+0.211SH+0.116SW;NN群体,mM2=-2.806+0.088SL+0.087SH;SS群体,mM3=-3.101+0.290SH。回归方程分析表明回归关系均达到极显著水平(P<0.01)。  相似文献   

6.
胶州湾是我国重要的菲律宾蛤仔(Ruditapes philippinarum)养殖基地,为探究湾内菲律宾蛤仔的生态容量及其碳汇功能,本研究采用Ecopath模型法评估了胶州湾菲律宾蛤仔的生态容量,并利用Ecosim模块动态分析了菲律宾蛤仔生物量扩大对胶州湾生态系统结构与功能特征的潜在影响,同时估算了胶州湾菲律宾蛤仔个体及种群水平的碳收支情况。结果显示,胶州湾菲律宾蛤仔的生态容量为239.9 t/km2,虽然整体水平尚未达到生态容量,但局部养殖区域已远超出了菲律宾蛤仔的生态容量;当胶州湾菲律宾蛤仔生物量从当前增加至生态容量时,生态系统总流量、容量、优势度和循环指数分别提高了16.0%、3.9%、47.1%和103.0%,而熵值降低了10.4%,表明此时生态系统具有更高的成熟度与稳定性,但菲律宾蛤仔生物量扩大至生态容量10倍时会对生态系统产生不利影响甚至崩溃;菲律宾蛤仔个体在1个养殖周期内约摄取3 310.1 mg C,其中约46.2%的碳沉降至海底,约13.2%的碳通过收获移出,如按菲律宾蛤仔生物量达到生态容量时计算,胶州湾每年将有1.5万t碳以生物沉积形式沉降至海底,有0.6万t碳以收获形式移出。研究结果为指导菲律宾蛤仔增养殖产业的健康可持续发展、阐明菲律宾蛤仔的碳汇功能提供了理论依据与数据支撑  相似文献   

7.
采集我国南北沿海9个地理群体的菲律宾蛤仔(Ruditapes philippinarum),利用通径分析等方法评估各群体形态性状对活体重和软体重的影响。结果显示,各群体壳长、壳高、壳宽和壳厚4 个形态性状对菲律宾蛤仔活体重和软体重的影响存在显著差异。除壳厚外,其他形态性状与活体重和软体重呈显著相关(P < 0.05)。通径分析和决定系数分析显示,大多数群体的壳宽对活体重和软体重的直接作用最大。2个形态比例参数(壳宽/壳长和壳高/壳长)最大值出现在山东莱州群体(0.49和0.74),而最小值出现在大连东港群体(0.42和0.67)。壳厚的变异系数最大(22.74),而壳高的变异系数最小(9.47)。通过检验偏回归系数的显著性,建立了各群体形态性状对软体重的最优回归方程。聚类分析表明,菲律宾蛤仔不同群体未出现明显的地域分布特征,而呈现出不规律的南北交替聚类现象。本研究查明了不同地理群体菲律宾蛤仔壳形态性状对体重性状的影响,为菲律宾蛤仔地理群体的形态判别、种质资源分析和遗传育种研究等提供了重要科学依据。  相似文献   

8.
不同温度与饵料浓度下菲律宾蛤仔的能量收支   总被引:9,自引:1,他引:8  
在静水系统中测定了实验条件下菲律宾蛤仔(Ruditapes philippinarum)的摄食率、吸收率、耗氧率和排泄率等生理指标;研究了软体部干重、温度和饵料浓度对菲律宾蛤仔最小碳需求量(WMCR)和能量收支的影响;建立了不同温度及饵料浓度下菲律宾蛤仔的能量收支方程。结果表明:最小碳需求量随个体软体部干重的增加而增加,温度越高其增加速率越快;软体部干重对生长效率没有显著的影响。温度通过影响耗氧率而显著影响单位软体部干重的最小碳需求量。在9—22℃范围内,菲律宾蛤仔的生长余力(SFG)随温度和饵料浓度的升高而增加,在较低温度和饵料浓度下蛤仔的SFG均出现负值。在能量收支方程中摄食能随温度变化显著,而呼吸耗能随温度的变化不明显。  相似文献   

9.
基于生态模型估算胶州湾菲律宾蛤仔养殖容量   总被引:2,自引:0,他引:2  
贝类的养殖容量是养殖功能海域的生态系统所能容纳的最大养殖个体数量。本文由实测资料建立了胶州湾生态模型,计算了浮游植物生物量,进而依据饵料收支平衡关系,估算了胶州湾菲律宾蛤仔的养殖容量,研究结果表明,各养殖区不同规格蛤仔的养殖容量在1月或3月份最大,9月份最小;胶州湾5个养殖区内,2~2.6cm、2.6~3.3cm和3.3~4cm 3种壳长规格菲律宾蛤仔的平均养殖容量分别为603枚/m2、441枚/m2和362枚/m2,胶州湾菲律宾蛤仔的播放密度已经饱和;为了保持最大产量、提高养殖品质的同时并将苗种成本降至最低,可适当降低播放密度;建议红岛东、红岛南、红岛西、胶州、黄岛等5个养殖区菲律宾蛤仔的放养密度分别为718枚/m2、693枚/m2、557枚/m2、805枚/m2和654枚/m2,胶州湾平均放养密度为690枚/m2。  相似文献   

10.
胶州湾移植底播菲律宾蛤仔的生长和死亡特性   总被引:3,自引:0,他引:3       下载免费PDF全文
2004年5月至2005年4月对胶州湾菲律宾蛤仔(Rudimpes philippinarum)底播增殖区进行了逐月定点采样,将样品带回放于实验室内水族箱暂养,每站随机取样,共对3269个个体进行了基本生物学特性测定,研究了移植底播菲律宾蛤仔的生长、死亡等渔业生物学特性。结果表明,底播增殖菲律宾蛤仔苗种的平均个体质量0.26g、平均壳长11.1mm;底播蛤仔与野生蛤仔在生长规律上基本一致,春末至秋初(4~9月)是其主要生长期;1~3龄期间个体生长速度较快,1~2龄、2~3龄,个体质量分别增长3.88g和4.02g;1~2龄生物量增长最快,2~3龄由于死亡率增大,其生物量增长缓慢;1~3龄蛤仔软体部的生长速度快于贝壳,5~6月是菲律宾蛤仔的繁殖肥育期。根据个体生长特性,3龄为最佳采捕年龄;根据目前的养殖状况,2龄蛤仔已达到商品规格,从生物量上分析,采捕2龄蛤仔收益最高;6月是最佳的捕获时期。蛤仔生长具有明显的季节变化,水温是影响菲律宾蛤仔生长的主要环境因子。[中国水产科学,2006,13(4):642—649]  相似文献   

11.
云龙湖水库青梢鲌的生长特性   总被引:1,自引:0,他引:1  
采用鳞片和耳石对取自云龙湖水库的青梢鲌(Erythroculter dabryi)进行了年龄鉴定,并对其生长特性进行分析。结果显示:以鳞片和耳石为年龄鉴定材料时,二者的吻合率分别为59.57%和90.16%。年龄鉴定结果显示,所捕获的青梢鲌由1~8龄个体组成,主要是3~5龄个体;个体体长与耳石半径之间呈直线相关:L=9.5632R-0.1595(R2=0.995,n=175),体重与体长呈指数函数相关:W=1.07×10-2L3.3035,其生长规律符合von Bertalanffy方程:Lt=20.4741(1-e-0.2531(t+0.8056)),Wt=229.5864(1-e-0.2531(t+0.8056))3.3035;青梢鲌生长拐点年龄为3.92龄,对应的体长为14.28 cm,体重为69.88 g;3.92龄为合理的捕捞时期。  相似文献   

12.
Growth hormone concentrations in juvenile cocho salmon were determined after intraperitoneal injections (yearlings; age 1+) and oral treatments (yearlings and fry; age 0+) with clonidine. Weights and lengths were also measured in coho juveniles fed diets supplemented with clonidine.
Plasma growth hormone concentration increased significantly (78.2%) 24 h after injection. Yearlings fed clonidine showed a significant increase (136%) in plasma growth hormone after 14 days, and levels remained elevated through 28 days (116%) before dropping to control levels at 42 days. Coho yearlings fed clonidine showed no significant increase in growth compared to controls after 56 days of treatment, but coho fry were significantly heavier (33%) and longer (8%) after 70 days.  相似文献   

13.
放养密度和投饲量对沟篮子鱼生长和饲料利用率的影响   总被引:7,自引:0,他引:7  
探索了不同放养密度和投饲量水平下沟篮子鱼的生长情况和饲料利用率。  相似文献   

14.
This study assessed the growth and survival over a year of two groups of 4‐month‐old turbot Scophthalmus maximus (L.) derived from artificial fertilization with fresh (FG) and cryopreserved sperm (CG). Growth in both groups, measured monthly in terms of length and weight, were compared. Survival was also recorded. No significant differences were found when we compared weight and length data in both groups. Growth rates were similar between FG and CG young turbot during 1 year. Likewise, the same survival rate (92.2%) was found in both groups. Our results show the good survival and growth of young turbot obtained from cryopreserved sperm, and confirm the cryopreservation technique as a useful tool for raising turbot for commercial purposes.  相似文献   

15.
Abstract. Loligo forbesi Steenstrup is a commercially and biomedically important species raneing from Scotland to North Africa and from the Azores Islands in the central Atlantic east through the Mediterranean Sea and Red Sea. Eggs were collected from Plymouth. England and from the Azores and the hatchlings were reared to adult size in recirculating seawater systems. Growth data were obtained primarily from mortalities during the course of three culture experiments which lasted 360, 240 and 480 days. Loligo forbesi hatched at a size of 5–9mg (3.0–4.6mm mantle length, ML) and grew to a maximum size of 124g (155 mm ML) in 413 days. In all experiments, growth was exponential in form for at least the first 3 months at rales of 5.8, 5.1 and 3.6% body weight per day (BW/d) at mean temperatures of 14.1, 14.0 and 13.1°C respectively. In one short-term experiment, month-old squids grew at 8.0% BW/d at 17.4°C. Growth beyond 3 months was slower and either logarithmic (as described by the power function) or exponential in form. Growth rates gradually declined to 1–2% BW/d, Analyses of mantle length growth confirmed the wet weight results. There was no evidence of sexual dimorphism in the laboratory populations, which were of small size, and the length-weight (L-W) relationships were found to be similar to those of field populations. Growth rates during the exponential growth phase appeared very sensitive to temperature, with a 1°C difference changing growth rate by 2% BW/d and producing a three-fold difference in weight at 90 days post-hatching. These dramatic effects of temperature on adult size and lifespan in nature are discussed. It is hypothesized that the small size of mature laboratory-reared squids was due to low culture temperatures during the first 3 months.  相似文献   

16.
Growth dynamics of five stocks of Arctic charr, were compared from the fry stage in June 1986 until December 1987. Each stock originated from a different lake in Sweden: Hornavan; Näckten; Torrön; Rensjön and Visjön. Hornavan charr reached the highest final mean weight (237 g), but they were not significantly heavier than Visjön charr (206 g). Growth of fish of the three remaining stocks was similar but less rapid. The superior growth performance of Hornavan charr was most pronounced during autumn. Coefficients of variation for individual size within stocks was between 30 and 54%, with Hornavan and Näckten charr displaying least variability. Charr from Lake Visjön had a significantly lower proportion of mature males (6%) than the other stocks (19–29%) at the end of the experiment. The results demonstrate that differences in growth potential exist between stocks of charr, and these differences may be related to differential seasonal rhythms in growth. Variations in early growth, size distributions and sexual maturation seemed to be subordinate factors affecting overall growth performance.  相似文献   

17.
Abstract.— The effects of temperature on growth and protein assimilation in leader prawns Penaeus monodon were evaluated. Growth of leader prawns was significantly ( P < 0.05) affected by temperature. The highest growth rate was 0.124 g/d at 32.0 C and optimum growth occurred between 27.5–32.0 C. Growth was described by an equation of the form: W t = Woekt ( R2 = 0.99). The relationship between temperature and growth was described by a curvilinear equation of the form: Y = a + bX + cX2 ( R2 = 0.70). Apparent protein assimilation efficiency was not significantly ( P > 0.05) affected by temperature.  相似文献   

18.
研究深水抗风浪网箱养殖斜带石斑鱼(Epinephelus coioides)的生长特性。经过125 d的养殖,斜带石斑鱼体重由15.2 g增加到102.8 g,平均日增长率为4.610%,体重和时间的关系式为M=12.247e0.014 7 t;全长由9.67 cm增加到19.36 cm,平均日增长率为0.802%,全长与时间的关系式为L=0.063 7 t+9.186 3;体重和全长的关系式为M=0.012 7 L3.051 1。  相似文献   

19.
Brook charr inhabit a wide variety of habitats and exhibit considerable growth variation within and among populations. We used biannual mark–recapture electrofishing surveys and PIT tags at two streams in coastal Maine to examine spatial and temporal variability in brook charr growth. We documented considerable stream‐to‐stream and year‐to‐year variation in the growth of coastal brook charr. Based on 2892 recaptures between 2006 and 2010, we developed a suite of linear mixed models to examine variation in individual growth rates at Stanley Brook as a function of environmental variables. We distilled physical habitat data from surveys in 2010 into principle components for entry into the growth model. Growth was related primarily to an interaction between season and body length, mean water temperature, and instream location. Growth rates were highest in the summer, and smaller individuals grew more rapidly than larger conspecifics in the same stream. Individuals using habitats closer to the head of tide grew faster than those in upstream locations. Physical habitat variation was not an important control of individual growth variation within Stanley Brook. We suggest local variability in growth rates should be considered when developing management strategies for coastal populations.  相似文献   

20.
Growth of second-year triploid and diploid bighead carp, Hypophthalmichthys nobilis, was compared in a 189- to 190-day yield trial; the fish were grown separately in 0.04-ha earthen ponds at 625/ha and were also grown communally in 0.05-ha earthen ponds at 640ha. When grown communally, bighead carp were polycultured with channel catfish, Ictalurus punctatus (7,50Oha), and grass carp, Cienopharyngodon idella (40/ha); when they were grown separately, they were polycultured with grass carp at 501ha. When cultured separately, diploids were longer (526 vs 499 mm) and heavier (1,645 vs 1,427 g) than the triploids at harvest, but the differences were not significant (P 5 0.05). When cultured communally, the diploids were significantly longer (519 vs 485 mm) and heavier (1,621 vs 1,321 g) than their triploid counterparts at harvest. Ploidy of all bighead carp was determined after fish were harvested, and 7.9% of the presumed triploids that were stocked separately were actually diploids. Growth of the triploids appeared to be acceptable for commercial use where diploid bighead carp are banned. The efficiency of producing triploid bighead carp must be improved if they are to be cultured in states where bighead carp are illegal.  相似文献   

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