河口海岸潮滩蟹类生物扰动行为过程研究进展

河口海岸潮滩是具有较高生物生产力和生物多样性的生态系统。蟹类作为一种典型的生态系统工程师,分布广泛、种类繁多,可影响整个潮滩生态系统的物质与能量循环。蟹类的分布与盐度、淹水时长、湿度、温度、底质等非生物因子有关,也与植被、捕食作用、种内种间竞争等生物因子和人类活动有关。蟹类挖掘洞穴,形成了优先排水通道,增加了土壤蒸发速率,改变了孔隙水循环以及土壤的物理化学性质,进而可影响潮滩泥沙稳定性以及微地貌形态,甚至会影响中长期潮滩地貌演变。目前,蟹类对于沉积物稳定性、泥沙输运规律、微地貌演变的影响依然有待深入研究,有必要开展中长期现场观测和试验、多因子驱动下系统演变数值模拟以及综合分析,推动相关研究从定性向定量层面迈进。     

VC对河蟹血清和组织中超氧化物歧化酶及磷酸酶活性的影响

研究了饲料中添加不同含量VC 对河蟹体内超氧化物歧化酶 (SOD)、碱性磷酸酶 (ALP)和酸性磷酸酶 (ACP)活性的影响 .结果表明 ,饲料中不添加VC 时 ,河蟹肝胰腺、卵巢、血清和肌肉各组织中SOD、ALP和ACP活性各异 ,其中SOD活性大小顺序为肝胰腺 >卵巢 >血清 >肌肉 ,ALP活性顺序为肝胰腺 >血清 >卵巢 >肌肉 ,而ACP活性则为肝胰腺 >血清 >肌肉 >卵巢 .饲料中VC 添加量分别 2 .5× 1 0 - 3 、5.0×1 0 - 3 、1 0 .0× 1 0 - 3 和 1 5.0× 1 0 - 3 (m m)时 ,与对照组相比 ,河蟹不同组织中SOD活性显著下降 (p <0 .0 5或 p <0 .0 1 ) ,而ALP、ACP这两种酶的活性却显著升高 (p <0 .0 5或 p <0 .0 1 ) .但它们的变化幅度不同 ,其中就肝胰腺、卵巢、血清和肌肉中SOD活性而言 ,VC 添加量为 1 5.0× 1 0 - 3 (m m )饲料组分别比对照组的低1 41 .3 4 %、1 2 5.94%、1 1 6.67%和 1 1 5.79%;ALP活性 ,VC 添加量为 1 0 .0× 1 0 - 3(m m)饲料组分别比对照组高 93 .0 %、77.5%、1 66.3 %和 2 66.4%;ACP活性 ,VC的添加量为 1 5.0× 1 0 - 3 (m m)饲料组分别比对照组高 1 3 0 .7%、2 3 7.4%、43 7.6%和 2 65.5%.饲料中VC 添加量为 (5.0～ 1 0 .0 )× 1 0 - 3 (m m )时 ,可有效地增强河蟹非特异性免疫能力 .此外 ,本实验还就VC     

中华绒螯蟹幼蟹维生素C营养需求研究

在每100g等氮、等能纯化饲料中分别添加0,100,200,400,800,1 000mg维生素C(Vc)多聚磷酸酯(LAPP),用这样配制成的试验饲料饲喂已淡化5d的河蟹大眼幼体及后续幼蟹25d,探讨Vc对大眼幼体和幼蟹生长、存活、蜕壳频率及抗逆性的影响,同时探明幼蟹对Vc的适宜需求量,结果表明,饲料Vc添加量为100~400mg/100g时,可以保证幼蟹正常生长、存活和蜕皮,尤其以投喂添加Vc200mg/100g(C₂组)和400mg/100g(C₃组)饲料的Ⅲ期幼蟹增重率、存活率和平均蜕皮频率较高,其中C₂组(上述各指标值)分别为516.18%,62.83%,2.58,C₃组分别为458.89%,66.17%,2.61;饲料中缺少Vc时(如C₀组),Ⅲ期幼蟹的增重率、存活率和平均蜕皮频率最低,分别为265.31%,26.67%和2.26.饲料中Vc的添加量达到800mg/100g(C₄)和1 000mg/100g(C₅)时,幼蟹的蜕皮反而受到抑制,平均蜕皮频率降低,蜕皮周期延长,且存活率降低,到Ⅲ期幼蟹的增重率、存活率和平均蜕皮频率在C₄组分别为355.7%,31.33%,2.39,在C₅组分别为307.53%,28.56%,2.19.此外,各处理组幼蟹对抗逆性影响的试验表明,在一定的范围内,饲料中添加Vc能提高幼蟹的耐低氧能力和耐pH突变能力,而对耐盐度突变能力没有明显的影响.综合上述结果可以得出,为保持幼蟹良好生产性能,饲料中添加的Vc?     

Heavy metal stress induced hyperglycemia in blue swimmer crab, Portunus pelagicus

The study was to find out the effect of cadmium and mercury on levels of hemolymph glucose, crustacean hyperglycemic hormone (CHH) and hepatopancreas glycogen in the blue swimmer crab Portunus pelagicus. The experiments were performed in both intact and eyestalk ablated crabs. Quantification of CHH was done by the indirect ELISA with the aid of primary anti-Carcinus maenas-CHH antibody. Higher glucose concentration was observed on exposure to 8×10^-6 of cadmium ((825.6±5.42) μg/mL) and 6×10^-6 of mercury ((90.5±6.25) μg/mL) after 48 h and 24 h respectively. Higher level of hemolymph glucose was observed in eyestalk intact crabs on exposure to cadmium and mercury than eyestalk ablated crabs. Decrease in the levels of CHH was observed in both eyestalk intact and ablated crabs on heavy metal exposure. Decline of the hepatopancreas glycogen level was also witnessed with the exposure to heavy metal, which validated its utilization in the production of glucose. Thus this study brings to light, the variations in hemolymph glucose, CHH and hepatopancreas glycogen on heavy metal stress. These carbohydrate metabolites can be used as biomarkers in assessing heavy metal contamination in water bodies.     

蟹类线粒体DNA的研究与应用

线粒体DNA作为理想的分子遗传标记已被广泛用于蟹类种群遗传学和进化遗传学的研究,并取得了许多有意义的结果。本文阐述了蟹类线粒体DNA分子生物学的研究进展,重点介绍蟹类线粒体DNA序列的研究概况及其多态性在蟹类系统学、种群识别、起源和进化、地理分化等研究中的应用情况。     

东太湖网围养蟹效应及养殖模式优化

通过2007年3月至12月对东太湖三个不同养殖密度和规模网围养蟹区养殖状况与环境的比较研究,分析不同养殖方式所带来的经济效益以及对湖泊环境的影响.结果表明:东太湖人工投饵单养河蟹的养殖方式,会造成水体氮磷营养盐累积,对水体造成污染.选取的A、B、C三个养殖区每产出1kg河蟹造成湖区氮累积量分别为0.24kg、0.33kg和0.30kg;磷累积量为0.043kg、0.059kg和0.051kg.比较各养殖区环境状况、经济效益以及河蟹生长规格,认为东太湖实施河蟹优化养殖的适宜密度和单个网围面积为6000只/hm2和2.33hm2左右,但是目前东太湖养殖方式仍需要改进.针对东太湖养殖面积过大和布局不合理现状,认为东太湖网围养蟹面积应控制在3165.2hm2以下为宜.     

虾蟹壳提取物氨基葡萄糖美拉德反应及其产物的抗氧化性能研究

首次使用虾蟹壳提取物氨基葡萄糖单一物质制备美拉德反应产物(MRPs)。结果表明,MRPs清除DPPH·能力随反应物浓度、温度和时间的增加而增强;还原能力、清除·OH能力随反应物浓度增加而增强,还原能力随温度、时间增加先增后降,清除·OH能力随温度升高先增后降,随反应时间下降。115℃、0.5mg/ml、90min条件下制备的MRPs清除DPPH·的能力最强为88.73%;65℃、0.6mg/ml、40min的MRPs还原能力最强为A700nm=1.684;65℃、0.6mg/ml、10min的MRPs清除·OH的能力最强为98.72%。MRPs具有很强的抗氧化活性,比Vc和TBHQ抗氧化效果更好,但其抗氧化能力并不完全依赖于产物的褐变程度。氨基葡萄糖MRPs是优良的新型保鲜剂材料。     

海水钙浓度对远海梭子蟹软壳持续时间与形态变化的影响

盐度30、pH7.5～8.5、温度27～30℃条件下,将刚刚蜕壳的远海梭子蟹放入不同钙浓度梯度(0～400 mg/L)的人工海水中,进行钙浓度对远海梭子蟹蟹壳硬化影响的实验。结果表明:0～12.5 mg/L浓度组的软壳持续时间在10.4～11.4 h之间,25～200 mg/L浓度组的软壳持续时间在6.1～7.7 h,400 mg/L浓度组的软壳持续时间为4.4 h;不同浓度组下,壳宽的增加差异不显著(P﹥0.05),壳长的增加差异也不显著(P﹥0.05);50 mg/L浓度组与400 mg/L浓度组体重增加差异显著(P<0.05),其它各浓度组之间体重增加差异不显著(P﹥0.05)。     

东海深海蟹类1新记录种——凹背熟盾蟹（甲壳动物亚门：十足目：宽甲蟹科）

在整理中国科学院海洋生物标本馆收藏的蟹类标本时,经形态分类学方法发现中国海宽甲蟹科1深海新记录种——凹背熟盾蟹Hephthopelta cribrorum Rathbun,1932。标本采自东海850m海底。凹背熟盾蟹以往仅有1雄性个体（正模）采自日本相模湾,本文首次报道此稀有种的雌性个体,并提供了鉴别特征及详细图片。     

Impacts of Habitat Complexity on Physiology: Purple Shore Crabs Tolerate Osmotic Stress for Shelter

Purple shore crabs, Hemigrapsus nudus (Crustacea: Decapoda), can survive indefinitely in salinities of 8 (25% SW), but also tolerate short-term exposure to salinities as low as 2. In the laboratory their salinity preference range, determined from choice chamber experiments, is 22–32 and they can discriminate between pairs of salinities separated by a difference of 2. These crabs show a strong positive thigmotaxis and a weak negative phototaxis and tend to choose environments with available shelter. The presence of shelter significantly alters the behaviour of this species. When shelter is available the salinity preference range is 10–32. Even in salinities below this preference range, the presence of shelter prolongs the time spent in the lower test salinities. This change in behaviour has implications on the crab's physiology: the haemolymph osmolality falls to lower levels when crabs remain in low salinity under shelters. In the field, H. nudus is found in creeks with salinities close to freshwater and they may remain in this salinity for up to 11 h, if there are rocks under which to shelter. An increase in habitat complexity increases the number of crabs that are found within the creek. These crabs in the low salinity environment have a lower haemolymph osmolality than crabs on the nearby open shore. In H. nudus the behavioural selection of a shelter appears to outweigh the physiological costs associated with osmotic regulation of the body fluids. Therefore, the distribution of H. nudus in estuaries may depend more on the availability of suitable habitats rather than the salinity tolerance of this species.