等边浅蛤Gomphina veneriformis的繁殖周期

本文根据1987.12～1989.4对舟山朱家尖岛南沙沙滩逐月采集标本进行研究。结果表明,等边浅蛤Gomphina veneriformis的性腺发育可分为5期:增殖期、生长期、成熟期、排放期和休止期。在舟山海区,等边浅蛤一年中为一个繁殖周期,繁殖期为8月下旬至9月中旬。有雄性早熟现象。     

等边浅蛤染色体核型分析的研究

取活的等边浅蛤鳃组织为材料,在Ringers液中浸泡后,进行秋水仙素处理,低渗作用后,利用卡诺固定液进行固定,采用滴片法制片,并尝试使用Photoshop软件建立贝类染色体核型图及核型模式图的方法,对等边浅蛤的染色体核型进行了研究,得出等边蛤染色体数目为2n=36,n=18,核型公式为2n=36=16m+20sm,未发现随体及性染色体。     

等边浅蛤Gomp hina venerif ormis生态习性的观察

本文对等边浅蛤进行了生态习性观察研究。结果表明,其生存温度为-3℃～35℃,盐度在11.4～36.9之间,且具有较强的耐干露能力。同时对等边浅蛤的食性作了分折,发现其胃内容物组成与自然海区浮游生物的组成相一致。     

北部湾大头白姑鱼生长特性及群体组成

利用2006年7月~2007年12月北部湾商业捕捞底拖网和流刺网渔获物中采集的样本,通过矢耳石研磨和生长轮观察,初步研究了北部湾大头白姑鱼的年龄与生长特性,并对其渔业生物学特征进行了分析。结果表明,北部湾大头白姑鱼优势体长145~185 mm,占69.7%;优势体重为80~200 g,占69.2%;年龄组成为当龄鱼~Ⅵ龄鱼,以Ⅰ龄鱼与Ⅱ龄与为主,分别占24.60%和50.96%;样本的雌雄性比为1.05∶1,繁殖期性比为1.13∶1。利用最大似然法估计von Bertalanffy、Logistic和Gompertz生长方程的生长参数,ARSS检验表明雌雄生长差异不显著,AIC和BIC检验得出von Bertalanffy生长方程为最适生长模型。主要参数分别为:L∞=229.95 mm,K=0.408,t0=-0.962;体重的生长拐点为1.753龄。     

菲律宾蛤仔(Ruditapes philippinarum)大连群体家系建立及生长比较

于2008年6月,以大连野生型蛤仔为材料,采用巢式设计即1个雄性亲本与3个雌性亲本交配的方式建立了菲律宾蛤仔15个半同胞家系(A,B,…,O)和45个全同胞家系(A1,A2,A3,…,O1,O2,O3)。对各家系的壳长、壳宽、壳高、鲜重等各项指标进行了方差分析和多重比较。结果表明,3、4、5月龄,菲律宾蛤仔45个全同胞家系的表型性状具有显著差异,且各月龄的差异趋势基本一致。5月龄时,从其生长性状上看,家系F2、G2、G3表现出明显的生长优势,壳长分别提高28.43%、24.72%、30.53%,壳宽分别提高21.14%、22.3%、25.58%,壳高分别提高30.88%、26.96%、25.25%,鲜重分别提高50.00%、68.42%、44.12%。从其存活上看,家系E3的四个表型性状在全同胞家系中最小,但存活数量最多为2269粒,表现出很强的抗逆性;具有生长优势的家系F2存活个数最少仅为43粒,抗逆性相对最差。从其产量上看,家系N3、I1、E3、C1、N1、G2产量较高,分别比平均产量提高了77.8%、75.61%、75%、69.45%、53.96%、50.19%。综合以上各项指标家系G2、G3、N3、E3、I1、C1、N1可作为优良的家系育种材料,在下一步育种工作中可以利用家系选择及家系杂交的方法对7个家系进行遗传改良。     

有效群体大小对蛤仔F1生长和存活影响

对不同有效群体大小(Ne=2、4、8、16、32、200)的蛤仔F1代生长和存活性状进行了比较。结果表明:浮游期,各试验组幼虫壳长均未表现出显著性差异(P0.05),实验组Ne=200的存活率低于其他各实验组,并随着日龄的增长,差异越来越显著;稚贝期,各实验组的壳长和存活率的变化规律和浮游期基本一致。对壳长变异情况分析表明,浮游期,随着群体有效含量的增大,子代开始出现小型个体和大型个体,壳长分布变异逐渐明显;稚贝期,各试验组组内壳长变异进一步加剧,除Ne=2试验组稚贝壳长介于400μm和600μm之间外,其他各试验组均出现明显的小型和大型个体,表现为有效群体越大,组内稚贝壳长变异越为明显。     

胶州湾菲律宾蛤仔生长特征研究

为对胶州湾菲律宾蛤仔增养殖业的可持续发展提供技术支持,2004年5～9月,通过对胶州湾菲律宾蛤仔进行定点采样调查和生物学特性测定,分析研究了菲律宾蛤仔的生长特征.结果表明：近几年胶州湾菲律宾蛤仔的底播增殖,苗种平均体重0.26g、壳长11.1mm;1～3龄期间个体生长速度较快,1～2龄、2～3龄,体重分别增长3.88g和4.02g;1～2龄生物量增长最快,2～3龄由于死亡率提高,使生物量增长缓慢;壳长、壳高、壳宽与体重关系式分别为y=0.000 2x^3.053 3,y=0.000 4x^3.088 6,y=0.005 3x^2.683 4,壳高、壳宽与壳长关系式分别为y=0.667 4x＋0.305 9,y=0.457 5x-0.967 8;1～3龄蛤仔软体部的生长速度快于贝壳,5～6月份是菲律宾蛤仔的肥育期.由个体生长特性分析,3龄为最佳采捕年龄,从生物量上分析,采捕2龄蛤收益最高;6月是最佳的捕获季节.     

帘蛤科4种养殖蛤群体遗传多样性和种间关系的fAFLP分析

利用荧光标记扩增片段长度多态性(fAFLP)技术对文蛤(Meretrix meretrix)、青蛤(Cyclina sinensis)、菲律宾蛤仔(Ruditapes philippinarum)和硬壳蛤(Mercenaria mercenaria)4种帘蛤科贝类的群体遗传多样性和种间关系进行了研究。选择EcoRⅠ/MseⅠ进行酶切,使用6个E 3/M 3引物组合进行扩增,共获得1 096个位点,多态位点比率95.1%,片段长度50~456 bp。其中,文蛤、青蛤、菲律宾蛤仔和硬壳蛤分别得到681,715,702和694个位点,相应的多态位点比率为76.8%,81.7%,83.0%和75.1%,得到17个种特异性位点,可作为4物种特征标记。分析了群体遗传相似系数和遗传多样性指数以及种间遗传相似系数。结果表明,硬壳蛤群体遗传相似系数最高(0.670 9),遗传多样性指数最低(0.236 0);菲律宾蛤仔群体遗传相似系数最低(0.592 5),遗传多样性指数最高(0.261 8);根据遗传相似系数采用UPGMA法构建了4物种32个体的聚类图,表明文蛤与菲律宾蛤仔遗传关系最近,青蛤与其他3物种遗传关系较远。     

The behavioral and antioxidant response of the bivalve Gomphina veneriformis to sediment burial effect

A laboratory-based microcosm experiment was carried out to examine both the behavioral and antioxidant response of the clam Gomphina veneriformis under the conditions of 3 types of burial material(sand,silt,silt-sand mixture) with 3 burial depths(5 cm,15 cm,30 cm).The concentration of dissolved oxygen decreased significantly after 3 d of burial in all experimental groups.In silt and sand-silt mixture groups,the interstitial water quality became worsened with lower pH,and higher NH_4~+-N concentration,where clam mortality occurred simultaneously.However,clam samples in all sand groups and 5 cm,15 cm sand-silt mixture groups survived well for 8 d.Obviously fewer individuals left in the bottom sand in the 15 cm,30 cm silt groups and 30 cm sand-silt mixture groups than in the 5 cm groups.Therefore,it suggests that adding silt and increasing burial depth could stimulate the vertical movement of organisms and cause lethal effects.It was found that the burial depth was the key factor that influenced the activities of antioxidant enzymes,such as superoxide dismutase(SOD) and catalase(CAT).The SOD and CAT activities in the gills and hepatopancreases of organisms both showed significant upregulation in 30 cm burial depth after buried for 8 d.Higher enzyme activities were found in gills than in hepatopancreases,which indicated that the gills of the bivalve G.veneriformis were more susceptible to burial effects than hepatopancreases.Overall,this study shows that sediment burial could cause effects on the biological behavior and antioxidant enzyme activities.     

围垦对舟山群岛海域潮流结构及潮能分布影响研究

舟山群岛海域潮能丰富,近年来大面积的围垦工程影响了邻近海域的潮流结构与潮能分布特征。基于FVCOM(finite volume coastal ocean model)三维水动力数值模型,选取1984年、2010年、2019年三个代表年份,探讨围垦工程影响下舟山群岛海域潮流结构与潮能分布的时空变化状况。结果显示:1984年至2010年间围垦面积相对不大,且较为分散,主要改变外海进入杭州湾各通道的潮能分配,对能量耗散的影响较小。2010年至2019年间的围垦工程缩窄了潮汐通道,流速增大使得螺头水道及邻近水道的潮能增加,近底流速增大与较强湍流涡旋的产生,使得围垦工程周边海域能量耗散更为集中。     

舟山群岛海域波浪对泥沙冲淤过程的影响

本文基于SWEM(Shallow Water Equation Model)三维水沙盐模式,考虑潮汐、径流、风场和波浪影响,在长江口与杭州湾及其邻近海域建立了一个高分辨的三维水沙盐模型。分析了一般天气条件下,舟山群岛海域在潮汐、径流、风场、波浪共同作用下的地形冲淤与悬沙含量分布特征,并对比分析了一般天气条件下与台风天气条件下波浪对泥沙冲淤过程的影响。一般天气条件下,舟山群岛海域东西向水道为冲刷特征,舟山群岛东侧海域以及舟山群岛内部南北向水道为淤积特征。舟山群岛海域暖半年冲刷增强,冷半年淤积增强。海域悬沙含量由西北向东南迅速降低,群岛“虑沙”效果明显。悬沙含量3月份最大,8月份最小。波浪对舟山群岛海域泥沙冲淤过程的总体影响在秋冬季较强,春夏季较弱。一般天气条件下与台风天气条件下,波浪对研究海域泥沙冲淤过程影响显著的区域均为朱家尖东侧海域,且波浪的影响特征均表现为促进淤积和增加悬沙含量。一般天气条件下波浪引起最大淤积约占总淤积量的10%。台风天气条件下波浪引起的淤积量约是同时段一般天气条件下的6倍。     

Influence of nutritional stress on digestive enzyme activities in juveniles of two marine clam species, Ruditapes decussatus and Venerupis pullastra

The potential use of digestive activities as indicators of the nutritional status in bivalves is discussed in relation to the results obtained in two clam species exposed to starvation and refeeding. Activities of some digestive enzymes (amylase, laminarinase, cellulase, and protease) were measured in juveniles of two commercially interesting species of clams, Ruditapes decussatus and Venerupis pullastra. The specimens were fed normally, being after subjected to a 15-days starvation and a further refeeding period. Samples were obtained at different moments of such feeding schedule to evaluate enzymes as well as weight (live, dry and organic) and length, in order to calculate growth rates and feeding efficiencies. Starvation led to a major decrease in clam growth as measured by dry weight and a negative growth as measured by organic weight, this coinciding with a certain degree of growth of the shell and a consumption of soft tissue. This response occurred more rapidly in R. decussatus but was of a lower magnitude than in V. pullastra. Activity of carbohydrases decreased rapidly in both species with starvation, although protease activity was maintained in R. decussatus. Recovery after the end of starvation was not similar in both species; while R. decussatus attained similar growth rates and enzyme activities to those measured prior to nutritional stress, V. pullastra only recovered 50% of its initial values. For both species of bivalves it can be concluded that digestive enzymes, and more specifically amylase, could be used as indicative of their nutritional condition.     

舟山群岛东侧海域蟹类群落结构及其与环境因子的关系

根据2018年4月（春季）和10月（秋季）在舟山群岛东侧海域（29°10′25.54"～30°45′00"N,122°53′3.88"～124°48′28.31"E）开展的渔业资源底拖网调查所获得的蟹类数据,研究了该海域蟹类资源的种类组成、优势种、生物多样性等群落结构特征,同时分析了蟹类数量分布及其群落结构与温、盐等环境因子之间的关系。结果表明,调查海域春、秋季蟹类种类共有40种,隶属于12科,23属;其中,春季优势种为双斑鲟（Charybdis bimaculata）,秋季优势种为双斑鲟和三疣梭子蟹（Portunus trituberculatus）,均为广温、广盐性种类;秋季丰富度指数（D）及Shannon-Wiener多样性指数（H'）高于春季,而Pielou均匀度指数（J'）则相差不大;独立样本T检验方法显示,春、秋两季渔获量之间存在显著性差异（p<0.01）;根据聚类分析与非度量多维标度排序分析,春、秋季蟹类均可划分为4个组群,SIMPER分析结果显示,秋季群落相似性大于春季;典范对应分析结果表明,底层水温和表层盐度是影响调查海域蟹类群落结构及数量分布的主要环境因子。     

近20年影响舟山群岛热带气旋规律与灾害探讨

利用浙江省台风历史年鉴提供的热带气旋资料,用统计的办法分析探讨近20a来影响舟山群岛的热带气旋的规律与灾害。研究结果发现：近20a发生的热带气旋明显减少,尤其是20世纪90年代;季节分布上呈现出现晚,结束早的特点,8月份发生的频率明显增加;热带气旋造成的灾害以严重、中等严重为主,在强度上没有减弱的趋势。     

舟山群岛海域网采浮游植物分布与多样性

于2014年夏、秋两季在舟山海域进行了浮游植物拖网采集和环境理化因子测定,共鉴定浮游植物6门92属184种,其中硅藻门127种,甲藻门30种,为调查海域主要浮游植物类群。夏季骨条藻Skeletonema spp.为绝对优势种,秋季优势种由琼氏圆筛藻Coscinodiscus jonesianus、虹彩圆筛藻Coscinodiscus oculus-iridis、蛇目圆筛藻Coscinodiscus argus、星脐圆筛藻Coscinodiscus asteromphalus、骨条藻Skeletonema spp.、尖刺伪菱形藻Pseudo-nitzschia pungens、并基角毛藻Chaetoceros decipiens、伏氏海毛藻Thalassiothrix frauenfeldii及中间肋缝藻Frustulia interposita等9种硅藻构成。调查海域夏季浮游植物平均丰度(1 713.58×10⁴个/m³)高于秋季(1 430.30×10⁴个/m³)。冗余分析表明,温度、盐度、悬浮物、溶解无机磷及溶解无机氮等环境因子对夏、秋两季浮游植物群落影响较大。结合历史数据分析可知,舟山海域近30 a来富营养化程度严重且日益加剧,富营养化指数明显升高;同时浮游植物群落变化也十分显著,主要体现为细胞丰度增加和优势种更替。     

台湾海峡游泳动物群落的空间结构及其季节变化

The Taiwan Strait is a transition zone between the East China Sea and the South China Sea with unique hydrology and a geographical environment that creates special marine community features.To analyze the spatial structure and seasonal changes of the nekton assemblages in the Taiwan Strait,seasonal experimental trawl surveys were conducted during 2006–2007.The results showed that there were two assemblages in the area with different sets of species,and the average similarity within each group varies between 39.38% and 74.20%.By using multivariate statistical analysis and analyzing the distribution of dominant species,we found that the structures of the assemblages had obvious seasonal variation.The middle region from the Putian transect to the Xiamen transect could be considered a mixing area for the two assemblages.The analysis of the relationship between species assemblages and environmental factors indicated that temperature was the most important factor affecting the community structure in cold seasons,and 22.5°C and 17°C could be considered dividing lines for spring and winter,respectively.In warm seasons,the most important factor was water depth,but the relationship with depth was not as significant,with a correlation between 0.264 and 0.399.The seasonal changes of nekton assemblages basically reflected the dynamic currents in the Taiwan Strait.The south coastal assemblage extended to nearly the entire area of the Taiwan Strait along with a strong and intense warm current that shrinks in spring and winter when the southward intrusion of the cold Zhejiang-Fujian coastal current becomes stronger.The impact of shortterm and long-term environmental changes,such as extreme weather,global warming and human activity on nekton assemblages,had been recognized but need further research.Our study on nekton assemblages could be used as a baseline for measuring future changes.