Morphometric and gonad maturity in the spider crab Maja brachydactyla: a comparison of methods for estimating size at maturity in species with determinate growth     

Corgos  Antonio; Freire  Juan 《ICES Journal of Marine Science》2006,63(5):851-859

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Protected areas and coastal and ocean management in México     

Juan E. Bezaury-Creel   《Ocean & Coastal Management》2005,48(11-12):1016

No explicit “integrated coastal and ocean management” policy or program has been formally instituted to manage coastal and marine issues in México. Nevertheless two existing environmental policy tools: ecological zoning programs and coastal and marine protected areas, which have incorporated interagency and multi-stakeholder participation within their design, are currently being used in lieu of such strategy. Coastal and marine protected areas in México are the result of independent initiatives taken over the last 75 years and as a group cannot be characterized as the result of a systematic approach. Nevertheless México's 55 coastal and marine protected areas currently with a valid legal decree, occupy 11,791,824 ha which represents 69% of Mexico's total protected area surface. Only 46% of these include marine ecosystems with a total of 3,577,527 ha with the remaining 8,216,194 ha consisting of coastal ecosystems. (See In press update.)  相似文献   

地衣芽孢杆菌胞外产物消化活性的研究   总被引：12，自引：0，他引：12  

曹煜成  李卓佳  冯娟  陈永青  吴灶和 《热带海洋学报》2005,24(6):6-12

将地衣芽孢杆菌Bacillus licheniformis的胞外产物置于不同的pH、温度和金属离子条件下,分别测定其蛋白酶、淀粉酶、脂肪酶活性的变化。结果表明,当pH为7.5—8.5时胞外产物表现出较高的蛋白酶和淀粉酶活性,胞外产物消化脂肪的最适pH为9.0—10.0。胞外产物水解淀粉、脂肪和蛋白质最适温度分别为60—80、40—60和50—70℃,60℃时蛋白酶活力最大。试验测定了8种金属离子对胞外产物活性的影响,发现Mg2+、Zn2+Cu2+可抑制其水解蛋白质,而Ca2+、Fe3+、Mn2+和Ba2+却无此影响;在胞外产物消化脂肪底物时Co2+、Fe3+、Mn2+和Ba2+均能抑制其活力,而Mg2+、Zn2+能使其消化活力升高,与前者相比,金属离子对淀粉水解的影响相对较小,仅Cu2+有一定的抑制作用,其它离子对其均无明显的影响。还研究了不同胞外产物浓度与生物学活性的相关性,发现当反应体系中胞外产物浓度升高时水解蛋白质的活力会相应降低,但对脂肪的消化活力则与胞外产物的浓度呈正相关。反应体系中胞外产物的浓度在0—132.4μg.ml-1时其水解淀粉的活力随浓度的升高而升高,浓度为191.0μg.ml-1时活力最大,浓度大于191.0μg.ml-1时活力不再变化,稳定在一个较高的水平。  相似文献   

锌离子(Zn2+)对坛紫菜叶状体光合色素含量的影响     

郭新梅  戴继勋  王娟  徐矫健 《中国海洋大学学报(自然科学版)》2007,37(1):107-110

采用不同浓度Zn2 处理坛紫菜叶状体,用紫外分光光度法,测定了光合色素的含量。研究了金属Zn2 对坛紫菜叶状体中光合色素:叶绿素a、藻红蛋白、藻蓝蛋白和别藻蓝蛋白的影响。结果表明:Zn2 在0.5~5.0μmol/L时,有利于光合色素的合成;但在5μmol/L时,叶绿素a含量开始下降,在Zn2 浓度>10μmol/L时各光合色素含量也随浓度的升高而下降,对光合色素产生毒害作用。除去Zn2 后,都表现出向对照组恢复靠近的趋势,但别藻蓝蛋白的恢复较慢。  相似文献   

A magnetic anomaly study offshore the Canary Archipelago     

M. Catalán  J. Martín Davila 《Marine Geophysical Researches》2003,24(1-2):129-148

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Cenozoic tectonics on the Galicia margin,northwest Spain     

Araceli?Mu?ozEmail author  Juan?Acosta  Elazar?Uchupi 《Geo-Marine Letters》2003,23(1):72-80

Neogene tectonic activity (Betic Orogeny) along the southern plate boundary of Iberia, as it converged with Africa and the Alboran Plate was inserted between them, propagated along Iberia's west side as far north as Galicia, northwest Spain. As the activity propagated northward, it reactivated structures formed during the Paleozoic (Hercynian), the Early Cretaceous opening of the northern North Atlantic and the Bay of Biscay, and the Paleogene Pyrenean Orogeny when Iberia collided with Eurasia. Recent earthquakes indicate that this tectonism is still active today as far north as northwest Spain.  相似文献   

鲍类微生物性疾病研究进展   总被引：4，自引：0，他引：4  

王瑞旋  徐力文  冯娟  王江勇 《海洋湖沼通报》2006,90(2):117-124

鲍类微生物性病害包括病毒性疾病、原核生物样疾病、细菌性疾病及真菌性疾病。本文就鲍类微生物病害的病原学、致病机制、组织病理学和流行病学等方面的进展,以及相关的诊断防治研究情况进行概述,以期为今后鲍类的病害防治研究提供依据。  相似文献   

Summer and winter plankton fish assemblages around offshore oil and gas platforms in south-eastern Australia     

Francisco J. Neira 《Estuarine, Coastal and Shelf Science》2005,63(4):72

Opportunistic plankton surveys were conducted within a 5-nmi radius of nine offshore oil and gas platforms in Bass Strait, south-eastern Australia, in February 1998 and 1999 (summer) and August 1998 (winter). The 108 day-night samples collected alongside (vertical tows) and nearby (surface and oblique tows) platforms yielded 1526 larval and early juvenile fishes representing 55 taxa from 45 families. Epipelagic/mesopelagic taxa dominated the catches, whereas hard/soft habitat-associated taxa were uncommon. Carangidae (36.2%) and Myctophidae (31.5%) dominated in summer and winter, respectively. The most abundant taxon was Trachurus declivis (Carangidae, 35.1%), followed by Bovichtus angustifrons (Bovichtidae, 8.7%), Scomberesox saurus (Scomberesocidae, 3.7%), Centroberyx affinis (Berycidae, 3.0%) and Arripis trutta (Arripidae, 1.7%). Fish concentrations (nos. per 100 m³) alongside platforms did not differ significantly between day and night across all surveys. Likewise, concentrations nearby platforms in February 1999, including those of T. declivis, did not vary significantly by tow type (surface vs. oblique) or day vs. night. The far greater diversity and abundance recorded in February 1999 are likely the result of upwelling conditions over the eastern Bass Strait shelf during the sampling period, and which were not detected in February 1998. In the absence of data on adult fishes associated with the Bass Strait platforms, and given the limited availability of reefs directly around the area, it could be argued that some of the taxa caught may originate from spawning around neighboring natural reefs, particularly those off the Gippsland coastline and the south-east corner of mainland Australia. However, the prime position of the platforms almost right in the center of a productivity “hotspot” would have a confounding effect on the potential source(s) of larval fishes in that region of south-eastern Australia. The role of platforms as potential de-facto reefs for juvenile fishes in Bass Strait, as well as spawning areas, is discussed based on the findings of this study, the first on early stages of fishes around oil and gas platforms in Australia.  相似文献   

军曹鱼营养成分的分析及评价   总被引：37，自引：1，他引：37  

李刘冬  陈毕生  冯娟  柯浩  蔡景心  范楷 《热带海洋学报》2002,21(1):76-82

对军曹鱼Rachycentron canadum Linnaeus进行解剖比较、营养分析和评价，结果显示，军曹鱼的含肉率为68．7％，肌肉蛋白质含量为21．2％，氨基酸总量为65．05％；蛋氨酸为第一限制氨基酸，其中赖氨酸含量高达591mg.gN^-1，军曹鱼的不饱和脂肪酸含量为65．2％，其中二十碳五烯酸（eicosapentaenoic acid，简称EPA）和二十二碳六烯酸（docosahexenoic acid简称DHA）的含量分别为4．5％和12．0％。研究结果表明，军曹鱼含肉率高，营养质量好，有较高的营养价值和药用价值。  相似文献   

Isotopic signatures of organic matter in sediments of the continental shelf facing the Orinoco Delta: Possible contribution of organic carbon from savannas     

Ernesto Medina  Marta Francisco  Leonel Sternberg  William T. Anderson 《Estuarine, Coastal and Shelf Science》2005,63(4):527-536

The ⁸⁷Sr, ¹³C, and ¹⁵N isotopic signatures of organic matter in sediments from the continental shelf facing the Orinoco Delta were measured to determine the contribution of sediments transported from the Amazon River by the coastal Guayana current and the sediments transported by the Orinoco River. Box core samples between 60 and 300 m water depth collected along 4 transects located eastwards to the Orinoco Delta were analyzed. Carbon and nitrogen concentrations decreased with depth under water on the shelf, and were strongly correlated indicating homogeneity of organic matter composition. Phosphorus content was also associated to organic matter in most samples, but some of them revealed deposition of P-enriched sediments. The ⁸⁷Sr/⁸⁶Sr ratios showed a strong continental signature averaging 0.7117, therefore, limiting the possible carbon and nitrogen sources associated with these sediments to C3 trees, C4 grasses, or freshwater phytoplankton. The δ¹³C values were relatively high averaging −21‰, above values reported for sediments on the Amapá shelf and the Amazon River in Brazil. Average δ¹³C values did not differ significantly among transects. High δ¹³C values point to the influence of organic matter transported from the C4-plants dominated savannas in the northern fringe of the Orinoco River. δ¹⁵N values were positive and averaged 5‰, being within the range of values measured in the Marajo island (Amazon River) and the estuary of the Pará River. The δ¹⁵N values differed significantly among transects (4.9–5.2‰), lowest values corresponding to the northernmost transect near the coast of Trinidad, and the highest values corresponding to the transect located at the southernmost position.  相似文献