盐度和温度对中华虎头蟹(Orithyia sinica) 存活和摄饵的影响

进行盐度和温度对中华虎头蟹存活和摄饵影响的试验,结果发现,盐度骤变时,盐度15—408d后蟹存活率100％。盐度10—45蟹能摄饵,日平均摄饵量达1．31g以上;盐度20—40是蟹适宜摄饵盐度,日平均摄饵量达3．65g以上;盐度30—35蟹摄饵最佳,日平均摄饵量达5．24g以上。盐度渐变时,盐度15—55蟹8d后存活100％;盐度5—50蟹能摄饵;盐度25—35为蟹摄饵适宜盐度,日平均摄饵量达4．13g以上;盐度30为最佳盐度,日平均摄饵量达4．53g。温度骤变时,10—30℃7d后蟹100％存活。10—35℃蟹能摄饵,日平均摄饵量达1．10g以上;20—30℃蟹摄饵最佳,日平均摄饵量逐渐增加,达8．76g以上。温度渐变时,0—30℃蟹7d后100％存活,35℃蟹存活率达80％。10—35℃蟹能摄饵;20—30℃蟹摄饵较佳,日平均摄饵量达12．61g以上;250C蟹摄饵最佳,13平均摄饵量达14．35g。     

三疣梭子蟹幼体和幼蟹的温度适应性

本文研究了不同温度对三疣梭子蟹（Portunus trituberculatus Miers）幼体发育和幼蟹存活及摄食的影响,试验结果表明：21—27℃有可能出苗,但21℃幼体发育相当慢;24—27℃是适宜育苗温度,27％是最佳育苗温度。蟹幼体在30℃以上仅发育至Z4,18℃以下,仅发育至Z3。温度骤变5d后,幼蟹在10—30℃存活100％,35℃存活75％,5℃以下仅能存活4h。存活幼蟹,20—30℃摄饵正常,日平均摄饵量达4．64g以上。5℃／d的温度渐变时,幼蟹在10—35℃存活100％,5℃存活25％,40℃存活不超过6h。存活幼蟹,30℃摄饵最佳,日平均摄饵量达9．80g;20—35℃摄饵正常,日平均摄饵量达5．1g以上;15℃和10℃摄饵很少,日平均摄饵量分别为0．5g和0．1g;5℃以下及40℃不摄饵。     

盐度对三疣梭子蟹摄食行为及生长特性的影响

从行为角度出发, 设置了 5、 10、 20、 30 和 40 五个盐度梯度 , 探讨不同盐度对梭子蟹幼蟹和成蟹的摄食行为及特性的影响。结果表明 : 在盐度 5 时, 除摄食活动外 , 幼蟹不外出游动且深潜底沙(约 0.5 cm); 在盐度 40 时, 幼蟹浅潜沙层 , 仅盖住背甲 (约 0.1 cm); 盐度为 10、 20 和 30 时, 除觅食活动外 , 幼蟹均外出游动。日摄食次数由幼蟹的 1 -2次增加到成蟹的 2-4 次。盐度为 10-40 时, 幼蟹平均日摄食量均维持在 0.0999 g·g−1 以上(每天每只梭子蟹单位体重所摄取食物的重量, 下同 ), 其中盐度为 20 时的日摄食量为最大(0.1974 g·g−1), 幼蟹生长的适宜盐度范围为 10-40, 最适为 20。此外 , 各盐度对成蟹的行为压迫不大, 对应的日平均摄食量亦无显著差别。     

温度、盐度对海月水母碟状体生长及存活的影响

海月水母为我国近海主要大型灾害水母种类之一,当自然环境适宜其生长与繁殖时,易出现暴发性的增殖现象,严重破坏了我国近岸海洋生态系统的稳点与平衡。采用实验生态学方法,研究了温度(2.5、5、7.5、10、15、20、25、27.5、30℃)和盐度(15、20、25、30、35、40)对海月水母碟状体存活与生长的影响,实验共进行30d。结果显示,在实验设置的温盐范围内,温度、盐度均显著影响碟状体的存活与生长。在盐度15-35条件下,海月水母碟状体可以在温度2.5-25℃存活,在15-25℃范围内可正常生长;在温度20-25℃和盐度20-30条件下适宜海月水母碟状体生长,其中温度20℃和盐度25条件下海月水母碟状体特定生长率达到最大。与盐度相比,温度对碟状体的影响较大,在盐度15-35条件下,随着温度的升高,碟状体的伞径逐渐增大,其碟状体形态向水母体形态的转变速度加快。在达到临界点25℃时,若继续升高温度,碟状体的生存率与生长率显著下降。温度与盐度对海月水母碟状体的生存与生长具有明显的交互效应,碟状体在实验过程中表现出在较低温度条件下提高了对较高盐度的适应性。研究表明,温度、盐度的变化显著影响碟状体的生长与存活,直接导致碟状体种群数量变动,进而影响成熟水母体种群数量。结论为进一步探索大型水母暴发的生态环境机理提供重要科学依据。     

温度和盐度对皱肋文蛤幼贝存活与生长的影响

在室内控制条件下,研究了不同海水温度和盐度对皱肋文蛤(Meretrix lyrata)幼贝存活与生长的影响。结果表明:皱肋文蛤幼贝适宜生存温度为12.2-35.6℃,最适生存温度为24-30℃;适宜生长温度为23.5-33.0℃,最适生长温度为27-30℃,属典型的南方滩涂贝类。皱肋文蛤幼贝适宜生存盐度为4.3-40.5,最适生存盐度为11-31;适宜生长盐度为17.1-33.4,最适生长盐度为19-23,属广盐性滩涂贝类。该贝低温和高温敏感起始点分别为21℃和33℃;低盐和高盐敏感起始点分别为9和33。皱肋文蛤幼贝对极端温、盐度具有一定的耐受力:在37℃下仍可保持6d,100%不死亡,在39、41℃下分别在3d和5d内全部死亡;在4、6、8、10、12℃下则可分别100%存活3、4、6、9、11d;在盐度为0、5、7、9时保持100%存活的时间分别为5、8、10、10d;在盐度为33、35、37、39时保持100%存活的时间分别为7、5、3、3d,盐度41时当天即出现死亡。     

大叶藻实生幼苗的盐度适宜性

在实验室条件下,研究了9个不同盐度处理(5、10、15、20、25、30(对照)、35、40、45)对大叶藻实生幼苗存活和生长的影响,分析了大叶藻实生幼苗的盐度适宜性。结果表明:经30 d培养试验,盐度5和10处理组实生幼苗很快腐烂,仅存活10 d,盐度20~45处理组的幼苗存活率在49%~58%,显著高于盐度5~15处理组(P0.05);盐度20处理组幼苗的形态学特征和生长率各指标均达到最大值,其中叶鞘长、根长和根生长率显著高于对照组和其他处理组,单株总叶片面积和叶片生长率与对照组无明显差异,但显著高于盐度15处理组和高盐(35~45)处理组(P0.05)。适宜性分析表明,大叶藻实生幼苗盐度耐受范围较广,但适宜生长的盐度范围仅在盐度20~30,最适生长盐度为20。本研究结果为建立海草实生苗的人工培育技术提供了理论依据。     

温度和盐度对青蛤孵化及幼虫、稚贝存活与生长变态的影响

在9个温度梯度(10-34℃)和10个盐度梯度(盐度3‰-50‰)条件下,研究了温度和盐度对青蛤孵化及幼 虫、稚贝生存与生长变态的影响。结果表明,青蛤孵化和浮游幼虫生长的适温范围为24-32℃,最适温度均为26- 30℃,稚贝生长的适温范围为22-32℃,最适温度为24-30℃。在最适温度下,D形幼虫变态率达80．7％-88．2％, 浮游幼虫和稚贝的存活率分别为86．2％-88．7％和81．5％-84．0％;孵化及浮游幼虫的生长适宜盐度为15‰- 30‰,稚贝为10‰-35‰,最适盐度均为20‰-25‰。在最适盐度下,D形幼虫的成活率、变态率、生长速度皆最高, 分别达到86．9％、77．5％和9．38×11．0μm/d,匍匐幼虫经14-14．5d发育至双管期稚贝,至双管期稚贝的成活率 82．5％-85．0％,日平均生长达13．1μm以上。与大多数滩涂贝类一样,青蛤属于广温广盐性贝类,且稚贝对低盐的 适应能力强于对高盐的适应能力。     

温度和盐度突变对菲律宾蛤仔斑马蛤耗氧率和排氨率的影响

为研究温度和盐度对蛤仔新品种斑马蛤耗氧排氨的影响,以野生蛤仔为对照,实验设置15、20、25、30和35℃五个温度梯度和20、25、30、35和40五个盐度梯度,结果表明:温度和盐度对斑马蛤的耗氧率和排氨率影响显著（P < 0.05）。在温度15-35℃内,随着温度的增加,耗氧率和排氨率整体上呈增加的趋势。在20-40盐度内,耗氧率随着盐度的升高先减少后增加,排氨率随着盐度的升高先增加后减少,在盐度为30时达到最高值。在水温为15℃,盐度20-40内,斑马蛤的O:N为9.534-62.008;在盐度为35,水温在15-35℃内,斑马蛤的O:N是20.700-74.138。与野生蛤仔比较,斑马蛤的耐高温能力要强于野生蛤仔,从Q₁₀的变化反映出斑马蛤对温度的敏感性相对较弱,适应温度变化的能力比较强;斑马蛤的耐低盐和耐高盐能力强于野生蛤仔。研究结果为进一步完善蛤仔斑马蛤的人工养殖技术提供参考。     

雪腐核盘菌菌核的萌发条件与致死温度

菌核是核盘菌Sclerotinia spp.在土壤中的主要存活形式和菌核病的主要初侵染源,在土壤中可存活8年以上,其数量和存活状况直接影响着菌核病的发生和危害程度。本研究以雪腐核盘菌Sclerotinia nivalis菌株SS-TB为材料,分析了菌核萌发的影响因素、致死温度以及土壤温度对菌核存活的影响。结果表明,未成熟菌核较成熟菌核更容易萌发;菌核萌发的最佳温度为20-25℃、pH为3.0-4.0、土壤含水量为20%-45%。菌核长时间浸泡水中对其存活不利,浸泡30d以后,存活率开始急剧下降,至47d时存活率为0。雪腐核盘菌菌核具有较强的耐高温特性,随着温度和处理时间的增加,菌核萌发率呈下降趋势。菌核在水浴中85℃ 5min、80℃ 10min、75℃ 10min、70℃ 30min、65℃ 120min、60℃ 180min时全部丧失活力。在土壤温度30℃和35℃处理5周、40℃和45℃处理4周时菌核全部失去活力。该研究结果为通过水旱轮作和土壤高温处理来防治西洋参菌核病提供了理论基础。     

盐度对宽壳全海笋稚贝存活与生长的影响

在20±1℃条件下,研究了盐度(15、20、25、30、35和40)对宽壳全海笋(Barnea dilatata)稚贝存活与生长的影响。结果表明:盐度对宽壳全海笋稚贝存活、贝壳生长与软体部有机物积累影响显著;盐度15~40是稚贝的适宜生存盐度,28 d平均存活率为78.7%~91.3%;稚贝的最适生存盐度为20~30,平均存活率高于90.0%;稚贝湿重增长的最适盐度为20~35,平均特定生长率为2.963~3.028%·d~(-1);不同盐度下稚贝壳长和壳高的特定生长率变化相近,壳长和壳高生长的适宜盐度为25~35;其中盐度30条件下稚贝有机物与无机物比值最高,达4.396,盐度25次之,为3.375,均显著高于其他各组。研究结果可以为宽壳全海笋的资源保护与增养殖提供参考。     

Observations on the morphology and histology of the foregut of Portunus sanguinolentus (Crustacea: Brachyura)

The morphological and histological characteristics of the foregut of the crab Portunus sanguinolentus (Herbst) are described, with special reference to the lining and glands of the oesophagus. The oesophagus is lined throughout with an outer keratin and an inner collagen layer. Glands secreting mucopolysaccharides are to be found embedded in the connective tissue of the oesophagus. Details of the armature of the pyloric stomach are given.     

Food segregation in three species of portunid crabs

Gastric mills of 2,619 specimens of portunid crabs(Portunus pelagicus, P. sanguinolentus andCharybdis feriatus) in Tolo Harbour, Hong Kongwere examined. Of these, 1,498 containedrecognizable food items. A total of 34 food items wereidentified, 10 of which (29.4%) were common to thethree crab species. The principal food items werebivalves, decapods, fish and algae. However, thepercent frequency of occurrence of these food itemsdiffered significantly (ANOVA, p < 0.001) among thecrabs. In addition to these principalfood items, differences were noted in other dietarycategories: P. pelagicusand P. sanguinolentus fed on the brittle starOphiura kinbergi, whereas P.sanguinolentus and C. feriatus fed on detritusand gastropods. The diet of P. sanguinolentuswas found to be more similar to C. feriatus thanto P. pelagicus. Exploitation of different fooditems and selective feeding on common prey may reduceinter-specific competition for natural food resourcesand allow the three portunid crabs to co-exist in thesame habitat. This revised version was published online in July 2006 with corrections to the Cover Date.     

蟹板茗荷在三疣梭子蟹体上的附着定向及种群变动

研究蟹板茗荷在三疣梭子蟹鳃及口肢上的定向、附着和种群特征 ,结果显示蟹板茗荷主要附着在三疣梭子蟹鳃的腹面 ,占 67.86% ,以在第五对鳃上的附着量最大。位于鳃腹面的蟹板茗荷主要以 0°方式定向 ,鳃背面的蟹板茗荷则主要以± 90°方式定向 ,鳃室壁上的蟹板茗荷主要以 0°方式定向。蟹板茗荷在不同的附着部位形态上有差异 ,口肢上的个体柄短、壳板厚而硬 ,鳃室里的柄长、壳板薄而软。附着于三疣梭子蟹鳃及口肢上的蟹板茗荷 ,其种群年龄结构和数量组成有明显的季节变化。     

三疣梭子蟹Na+/H+-exchanger基因克隆鉴定及在盐度胁迫下的表达分析

为研究Na+/H+-exchanger基因在三疣梭子蟹（Portunus trituberculatus）盐度胁迫过程中的功能作用,克隆了三疣梭子蟹Na+/H+-exchanger基因并进行表达分析。结果显示,Na+/H+-exchanger基因（GenBank:KU519329）全长4233 bp,5和3非编码区（UTR）长分别为519和753 bp,开放阅读框（ORF）长2961 bp。编码986个氨基酸,预测蛋白质分子量和等电点分别为110.8 kD和7.42,具有信号肽和典型的Na+/H+-exchanger蛋白结构域,含12个跨膜螺旋;三疣梭子蟹Na+/H+-exchanger基因与普通滨蟹（Carcinus maenas）同源性最高,达到87.2%,系统进化分析也显示该序列与普通滨蟹聚为一支;表达分析显示,三疣梭子蟹Na+/H+-exchanger基因在鳃中表达量最高;在低盐（盐度5、10和20）胁迫过程中,Na+/H+-exchanger基因在0-12h上调表达明显,在24-168h间表达量呈下降趋势;在高盐（盐度50）胁迫初期（0-12h）,该基因表达量相对稳定,之后（24-168h）显著下调表达。研究表明低盐显著诱导Na+/H+-exchanger基因的高表达,推测三疣梭子蟹Na+/H+-exchanger基因在低盐环境下发挥重要的渗透调节功能。     

Intact chemoreceptor-based biosensors.

A receptrode biosensor is presented that uses intact chemoreceptor-based molecular recognition from antennular structures of the Hawaiian swimming crab species Portunis sanguinolentus. The sensor is coupled to a learning, pattern recognition calculation for performing analytical chemistry. Action potential waveforms are used to establish the identity of individual action potential types that can be associated to particular analytes. The pattern recognition calculations used are referred to as cluster analysis (CA) and principal component analysis (PCA). Action potential similarities are determined by using a dendrogram plot of the cluster analysis results and further elucidated by using principal component scores plots. Quantitative analysis was performed after classification of analyte and background responses. Chemoresponses to salinity and trimethylamine N-oxide, two chemical constituents that are found in the crustacean living environment, were investigated and gave analytic responses over several orders of magnitude.     

Observations on the morphology and histochemistry of the midgut and hindgut of Portunus sanguinolentus (Herbst) (Crustaceans: Brachyura)

The midgut of Portunus sanguinolentus comprises the intestine, the anterior and posterior midgut caeca and the hepatopancreas. The hindgut comprises the rectum, which continues to the anus, a slit-like opening on the ventral surface of the telson. The limits of the midgut and hindgut are specified. The midgut has no cuticle, whereas the hindgut is lined with a cuticle composed of an outer keratin and an inner collagen layer. Four types of cells--E,R,F, and B--were differentiated in the hepatopancreas. Histochemically, the hepatopancreas contains moderate amounts of glycogen and large quantities of lipids and proteins, but no mucopolysaccharides.     

Studies of the neurohaemal organ (sinus gland) of the portunid crab Portunus sanguinolentus (Herbst) (Brachyura). 1. Morphology and histology in relation to moulting

The morphological and histological characters of the neurohaemal organ (sinus gland) of Portunus sanguinolentus are described in detail. The sinus gland lies on the dorsal surface of the optic ganglia, opposite the medulla interna. Histological techniques showed the presence of three tinctorially different secretory granules in the sinus gland. The predominant type of secretory material is basophilic and occurs as large granules, while two types of acidophilic material occur near the basement membrane. Cyclic changes in the relative amounts of acidophilic and basophilic material in correlation to moulting are also discussed. Allochthonous cells present in the sinus gland are identified.     

Biocontrol method in aquaculture for rearing the swimming crab larvae Portunus trituberculatus

The aim of this work is to control the waterenvironment for culturing larvae of the swimmingcrab, Portunus trituberculatus, using microorganisms.The bacterial strain PM-4 (Thalassobacter utilis)improved the survival rate of crab larvae andrepressed the growth of Vibrio anguillarum (bacterium)and Haliphthoros sp.(fungus) in seawater. PM-4 wascultured and added daily to seawater during the firstto third zoean growth stage of the crab with diatomsand rotifers. Numbers of PM-4 decreased in culturewater during the first 3 days, because of feeding bythe first zoean stage of larvae. The finalconcentration of PM-4 was 10⁵ to 10⁶ cellsml^–1according to the plate count method in larval rearingwater.During 1989 to 1993, we tried seed productions of aswimming crab in 200 m³ containers at TamanoStation, Japan Sea-Farming Association. In 33trials of the biocontrol methods, average survivalrate of crab larvae was 28.3% when the bacterialstrain PM-4 was added. In 42 trials in which the strainPM-4 was not added, average survival rate of crab larvae was15.6%. We conclude that thebacterial strain PM-4 is effective as a biocontrolagent.     

Studies of the seminal receptacle of the crab Portunus sanguinolentus (Portunidae: Brachyura)

The seminal receptacle or spermatheca of Portunus sanguinolentus consists of two parts--an anterior glandular and a posterior chitinous part. The chitinous part continues as the oviduct, which opens on the sternite of the sixth thoracic segment. Significant morphological and histological differences were observed between the spermatheca, as well as the oviduct, of mated and unmated crabs. In mated crabs the spermatheca is much more bulging, owing to receipt of a copious supply of seminal products, and its cells are hyperactive. Further stages of ovarian development were observed as indicators of sequential changes in the spermatheca. The secretory cells gradually disintegrate by way of holocrine secretion; this results in cellular stratification and the formation of distinct furrows in the chitinous posterior part.