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东山湾翡翠贻贝海区半人工采苗技术研究 总被引：1，自引：0，他引：1
本文研究了东山湾翡翠贻贝的繁殖期，附苗期及海区半人工采苗技术。结果表明：东山湾翡翠贻贝的繁殖期在５－１０月，其５－６月为繁殖盛期。贻贝附苗季节在６－１１月，主要附苗季节在６月上中旬至７月初。通过对东山湾７片采苗区海水理化因子的测定和采苗效果的比较试验，确定了东山湾合适的采苗区为２＾＃－６＾＃区，其中３＾＃，４＾３，５＾＃区采苗效果最好，同时筛选出了木麻黄，胶皮合股绳和泡沫编织袋等３种附苗效果较好的 相似文献
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Oceanic uptake of anthropogenic carbon dioxide results in a decrease in seawater pH, a process known as "ocean acidification". The pearl oyster Pinctada fucata, the noble scallop Chlamys nobilis, and the green-lipped mussel Perna viridis are species of economic and ecological importance along the southern coast of China. We evaluated the effects of seawater acidification on clearance, respiration, and excretion rates in these three species. The animals were reared in seawater at pH 8.1 (control), 7.7, or 7.4. The clearance rate was highest at pH 7.7 for P. fucata and at pH 8.1 for C. nobilis and P. viridis. The pH had little effecton the respiration rate of P. fucata and P. viridis. In contrast, the respiration rate was significantly lower atpH 7.4 in C. nobilis. The excretion rate was significantly lower at pH 7.4 than pH 8.1 for all species. Theresults indicate that the reduction in seawater pH likely affected the metabolic process (food intake, oxygenconsumption, and ammonia excretion) of these bivalves. Different species respond differently to seawateracidification. Further studies are needed to demonstrate the exact mechanisms for this effect and evaluateadaptability of these bivalves to future acidified oceans. 相似文献
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Application of oxidative stress indices in natural populations of Perna viridis as biomarker of environmental pollution 总被引：2，自引：0，他引：2
Oxidative stress indices were measured in gills and digestive glands of Perna viridis collected from three coastal locations in Goa i.e., Bambolim, Marmugao Harbour and Malim. In addition to lipid peroxidation, the activities of antioxidant enzymes such as superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glutathione S-transferase and two non-enzymatic antioxidants (ascorbic acid and reduced glutathione) were investigated in order to understand their variation with respect to pollution status of the sampling locations. We observed a significant increase in lipid peroxidation and antioxidant enzymes of both the tissues at Mormugao Harbour and Malim, suggesting that the animals at these two locations are at higher level of oxidative stress as compared to those at Bambolim. Conversely, low levels of non-enzymatic antioxidants such as ascorbic acid and reduced glutathione, observed at Mormugao Harbour and Malim indicate that the animals may use these compounds to counteract stress in the tissues. This study shows that changes in lipid peroxidation, superoxide dismutase, catalase, glutathione reductase, glutathione S-transferase and reduced glutathione in tissues of P. viridis can be used as molecular biomarkers in environmental monitoring programs. 相似文献
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Bruce J. Richardson Eva Mak Sharon B. De Luca-Abbott Michael Martin Katherine McClellan Paul K.S. Lam 《Marine pollution bulletin》2008,57(6-12):503
Polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCs) are generally present in the marine environment in complex mixtures. The ecotoxicological nature of contaminant interactions, however, is poorly understood, with most scientific observations derived from single contaminant exposure experiments. The objective of this experiment was to examine dose-response relationships between antioxidant parameters and body contaminant levels in mussels exposed to different exposure regimes under laboratory conditions. Accordingly, the green-lipped mussel, Perna viridis, was challenged with a mixture of PAHs (anthracene, fluoranthene, pyrene, benzo[a]pyrene) and OC pesticides (α-HCH, aldrin, dieldrin, p,p′-DDT) over a 4 week period. Contaminants were delivered under four different dosing regimes, with all treatments receiving the same total contaminant load by the end of the exposure period. Antioxidant biomarkers were measured after 1, 2, 3 and 4 weeks, including glutathione (GSH), gluathione-S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and lipid peroxidase (LPO). GST and CAT were induced in hepatic tissues in most of the exposure regimes, with the majority of significant induction occurring in a constant exposure regime and a two-step alternate exposure regime. Significant differences among exposure regimes were detected in the body burden of contaminants after 28 days. Hepatic CAT and GSH are proposed as potentially useful biomarkers as they showed good correlation with target contaminants and were not readily affected by different dosing patterns. 相似文献
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Due to their close proximity to the point sources of pollution, estuaries and harbours are exposed to metals. Mussels are used worldwide to monitor marine pollution due to their ability to take up contaminants and the ease of transplantation. Mussels were collected from two reference sites and transplanted in Richards Bay Harbour (2006 and 2010) and in three harbours. Transplanted and resident mussels were removed after 6 weeks exposure and metal concentrations were analysed using ICP-MS techniques. Transplanted mussels had higher metal concentrations than the resident mussels. This was attributed to regulation of metals by the resident mussels. Metal regulation was greater in mussels that are continuously submerged as opposed to those that undergo tidal influences. For monitoring it is essential that the reference population for transplantation is considered carefully as upwelling events in the pristine reference location results in significant increases in metal bioaccumulation. 相似文献
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运用差异系数检验、主成分分析、判别分析和聚类分析等4种多元统计分析方法,采用5个比例性状,比较研究了广西北海、广东湛江和汕尾的3个翡翠贻贝野生种群的形态性状差异。结果表明:(1)3个种群间5个比例性状的差异系数在0.024～1.134之间,种群间尚未达到亚种差异水平;(2)主成分分析构建了3个主成分,PC1、PC2和PC3贡献率分别为40.134%、27.956%和20.614%,累计贡献率为88.704%;(3)利用逐步判别法选择3个贡献率较大的性状进行判别分析,建立了3种群判别函数,判别准确率为P1为73.0%～88.0%,P2为74.6%～86.8%,综合判别率为79.7%;(4)聚类分析显示,北海种群与汕尾种群形态较为接近,湛江种群趋异程度最大。各种分析方法从不同角度反映了群体间的形态学差异,这种差异是环境和遗传共同作用的结果。 相似文献
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The brown mussel, Perna perna, is an ecologically important species which has a great potential for aquaculture in Ghana. Though it is harvested from the wild for consumption locally, there is no information on its population parameters to guide its management and subsequent culturing. The species inhabiting Iture rocky beach near Cape Coast (Ghana) was therefore investigated to elucidate its growth and other population parameters. Specimens had shell length ranging from 5.00 to 78.0 mm, a modal shell length class of 35.0–39.9 mm, and exhibited negative allometric growth. The asymptotic length (L∞), growth coefficient (K), and growth performance index (Φ') were 80.10 mm, 0.49 per year, and 3.49, respectively. The recruitment pattern showed that P. perna has year-round recruitment with a single peak between April and July. Total mortality (Z) was estimated at 2.79 per year, while natural mortality (M) and fishing mortality (F) were 0.87 and 1.92 per year, respectively. The calculated exploitation level of the population (E = 0.69) suggests possible overfishing of the mussels at Iture rocky beach. These results could serve as baseline information for management of the mussel population in Ghana. 相似文献
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E. Louise Allan Shan T. AmbroseNicole B. Richoux P. William Froneman 《Estuarine, Coastal and Shelf Science》2010
Mesoscale oceanographic features, such as upwellings, are known to play an important role in regulating the structure and productivity of nearshore marine communities. Stable isotope (δ13C and δ15N) and fatty acid analyses were employed to assess the influence of an upwelling cell along the south-eastern coastline of southern Africa on the diet of the mussel, Perna perna. Eight sites were sampled: two upstream, three in the vicinity and three downstream of the upwelling cell. Stable isotope and fatty acid signatures indicated that the mussels consumed a diet of detritus derived mainly from macroalgae, diatoms and dinoflagellates. One-way ANOVA on the δ13C and δ15N signatures and the principal component analysis of the fatty acid profiles of the mussels identified distinct groups corresponding to the above mentioned regions. The proportion of diatom biomarkers in the fatty acid profiles decreased downstream of the upwelling region while the proportion of dinoflagellate biomarkers increased. Upwelling regions are typically associated with elevated levels of productivity; however, these systems usually become silicon depleted and result in the replacement of diatoms with dinoflagellates. The highest proportions of the dinoflagellate markers were recorded in the two furthest sites downstream of the upwelling cell. The spatial variation in the diet of the mussels, therefore, appears to reflect the presence of the upwelling cell in the nearshore biology of the region. 相似文献
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Cardiac and Lysosomal Responses to Periodic Copper in the Mussel Perna viridis (Bivalvia: Mytilidae)
Shaun Nicholson 《Marine pollution bulletin》1999,38(12):65-1162
Biological monitoring of metals in marine waters often employs tissue residue analyses from bivalves. Chemical residues in tissues do not elucidate biological injury, however, whereas biomarkers, do afford sensitive stress indices. Physiological and cytological responses were evaluated in laboratory experiments from the mussel Perna viridis in order to assess the species’ suitability for pollution monitoring in the tropics. Periodic copper exposure increased tissue residues but failed to perturb cardiac activity. Copper destabilized haemocyte lysosomal membranes in a exposure-dependent relationship showing a sensitive, rapid, indication of stress. Cytological biomarkers from P. viridis have potential as indices of pollutant exposure and could facilitate effective biomonitoring of water quality throughout South-east Asia. 相似文献