红树林在海洋经济中的地位和作用

从多个方面论述了红树林在海洋经济可持续发展中的地位和作用。红树林除了在海洋抗灾、减灾,防治海洋污染,保护与改良耕地,保护海洋生物多样性等方面具有重要意义外,还在海洋药业、化工、饲料、造船等行业具有重要的作用     

镇海石化成品可溶性物质对海洋环境的影响预测

本文采用Joseph-Sendner扩散模型,以龙海市镇海石化成品油罐区项目为例,对分散于水中可溶性物质对海洋水环境的影响进行预测、分析。在介绍Joseph-Sendner扩散模型的基础上,主要预测溶解油品、苯酚等可溶性物质以及施工挖泥产生的悬浮泥沙泄溢入海后的扩散、迁移变化状况以及影响范围,从而分析、探讨了分散于水中可溶性物质对海洋水环境的污染程度。     

Viability of a bottom‐set tray ocean nursery system for Holothuria scabra Jaeger 1833

Scaling up the hatchery production of juvenile sandfish Holothuria scabra is constrained by limited hatchery space and the associated high operational costs. To shorten the hatchery rearing phase, ocean nursery systems like floating hapa nets have been used with good prospects but with limitations during rough sea conditions. In this study, the potential of bottom‐set trays (0.14 m²) as an alternative ocean nursery system for early sandfish juveniles (0.5 ± 0.1 cm) was evaluated. The effects of stocking density and presence of artificial substrates (AS) on the growth and survival were determined in a 60‐day field experiment. Average length and growth rates at lower stocking density treatment (100 individuals tray^?1) were significantly higher (1.45 ± 0.22 cm; 0.03 ± 0.01 cm day^?1) than at higher stocking density treatments (400 and 500 individuals tray^?1) 0.95 ± 0.06 cm; 0.03 ± 0.004 cm day^?1) with or without AS (p < .05) respectively. The coefficient of variation in length (CV) at high stocking densities were significantly higher than at low densities (p < .05) and growth rate was strongly negatively correlated with density. Survival was significantly higher (55% ± 9%) in trays with AS across all stocking density treatments than in trays without AS (34% ± 2%). Results suggest that AS may have reduced intra‐ and interspecific interactions, resulting to significantly lower growth variations and higher survival. The bottom‐set tray with AS can be a practical alternative ocean nursery unit for rearing early sandfish juveniles particularly when the sea surface condition is rough. With improved design and density management, survival and growth may be further enhanced.     

Incidental capture of leatherback sea turtles in fixed fishing gear off Atlantic Canada

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Effectiveness of shore‐based remote camera monitoring for quantifying recreational fisher compliance in marine conservation areas

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Population structure,distribution and habitat use of the Critically Endangered Angelshark,Squatina squatina,in the Canary Islands

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Interannual variability in the feeding and condition of subyearling Chinook salmon off Oregon and Washington in relation to fluctuating ocean conditions

Chinook salmon (Oncorhynchus tshawytscha) is one of several economically‐important species of salmon found in the Northeast Pacific Ocean. The first months at sea are believed to be the most critical for salmon survival, with the highest rate of mortality occurring during this period. In the present study, we examined interannual diet composition and body condition trends for late‐summer subyearling Chinook salmon caught off Oregon and Washington from 1998 to 2012. Interannual variability was observed in juvenile salmon diet composition by weight of prey consumed. Juvenile subyearling Chinook salmon were mainly piscivorous, with northern anchovy (Engraulis mordax) being especially important, making up half the diet by weight in some years. Annual diets clustered into two groups, primarily defined by their proportion of invertebrate prey (14% versus 39% on average). Diet composition was found to influence adult returns, with salmon from high‐invertebrate years returning in significantly larger numbers 2–3 yrs later. However, years that had high adult returns had overall lower stomach fullness and poorer body condition as juveniles, a counterintuitive result potentially driven by the enhanced survival of less fit individuals in better ocean conditions (top‐down effect). Ocean conditions in years with a higher percentage of invertebrates in salmon diets were significantly cooler from May to August, and bottom‐up processes may have led to a fall plankton community with a larger proportion of invertebrates. Our results suggest that the plankton community assemblage during this first fall may be critical in predicting adult returns of Chinook salmon in the Pacific Northwest.     

Elevated CO2 does not exacerbate nutritional stress in larvae of a Pacific flatfish

Multiple aspects of climate change are expected to co‐occur such that ocean acidification will take place in conjunction with warming and a range of trophic changes. Previous studies have demonstrated that nutritional condition plays a significant role in the responses of invertebrates to ocean acidification, but similar studies have yet to be conducted with marine fishes. In this study, we examined the potential interactive effects of elevated CO₂ levels and nutritional stress on the growth and development of northern rock sole (Lepidopsetta polyxystra). Separate experiments examined the effects of these two environmental stressors during the pre‐flexion (3–31 days) and post‐flexion (31–87 days) larval stages. In both stages, the larval feeding regime has a much larger impact on growth rates than did the CO₂ level, and there was no observed interaction between stressors. By 31 days post‐hatch, larvae in the high‐feeding treatment were 84.2% heavier than the fish in the low‐feeding treatments, but there was no significant effect of CO₂ level on body size or condition. While overall growth rates were faster during the pre‐flexion stage, the effects of food limitation were greater for post‐flexion larvae undergoing metamorphosis, with the high‐feeding treatment fish being 3.3 times as heavy as fish in the low‐feeding treatments. These results have important implications for understanding the impacts of the multi‐faceted nature of climate change on population productivity of commercial fish species in the North Pacific.     

Fine‐scale population structure and connectivity of bottlenose dolphins,Tursiops truncatus,in European waters and implications for conservation

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