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1.
The contribution that Leigh Marine Reserve in northern New Zealand makes to the local spiny lobster fishery was examined by comparing the catch characteristics of Jasus edwardsii around the reserve boundary with those from Coastal Leigh, 0.3-2 km from the reserve, and Little Barrier Island, 22-30 km from the reserve. Seasonal trends were apparent in the reserve catch characteristics, consistent with lobster movements into and out of offshore fishing areas adjacent to the boundary. No significant difference was detected in catch per unit effort (kg.trap haul -1 ) among locations. However, the catch around the marine reserve consisted of fewer but larger lobsters than at Little Barrier Island, while the size and number of lobsters caught per trap haul at Coastal Leigh was intermediate between the other two locations. Catch rates around the reserve were more variable than at the other sites, but on average, the amount of money made per trap haul was similar to Little Barrier Island and Coastal Leigh. 相似文献
2.
Stephen M. Holland 《Coastal management》2013,41(2):219-238
Abstract Artificial reef development involves pfonning from a number of perspectives including biological, océanographie, engineering, and social. This article reviews previous studies and identifies demographic variables that affect the use of artificial reefs by recreational anglers. An index of relative demand was created employing eight components: number of coastal county resident boat anglers, nonresident boat anglers, tourist boat anglers, nonboat anglers, number of fishing clubs, number of charter/party boats, number of registered pleasure boats, and the rate of county population growth. By comparing the magnitude of the index to the number of existing artificial reefs off of Florida's 35 coastal counties, an estimate of relative need was graphically portrayed on a state map. Indian River county on the Atlantic coast and Hernando, Hillsborough, Pasco, Citrus, Levy, Lee, and Charlotte counties on the central Gulf coast are the areas with the greatest demand relative to existing reef supply. 相似文献
3.
Wen-Hong Liu Kun-Lung Lin Hao-Tang Jhan Ta-Ly Lin De-Lu Ding Ching-Hsien Ho 《Coastal management》2013,41(5):515-535
A sustainable fisheries development indicator system (SFDIS) is proposed in this article to monitor management of Taiwan's offshore and coastal fisheries. Demonstration of its application shows that the ecological index is tending toward sustainability but to conserve fisheries’ resources it is necessary to strengthen habitat protection and management through a partnership approach. The economic index is tending toward unsustainability as a result of a decline in fisheries’ Gross Domestic Product (GDP), value, economic production, and investment. An aging fisherman population and decreasing social performance and resilience contribute to unsustainability of the social index. By contrast, the institutional index is sustainable because of improved management efficiency, ability, and capacity-building. However, some problems exist with regard to compliance and acceptability of institutional expense. Overall, the SFDIS suggests that an increase in employee number, incorrect statistical data, and unacceptable institutional expense will make Taiwan's offshore and coastal fisheries unsustainable in the long run. 相似文献
4.
科学的施工管理能保证工程的安全、质量和进度,还能使工程的效益最大化.在某核电厂西部陆域软基加固工程中采用合理有效的施工管理方法,解决了工程中遇到的排水板打设困难和堆载过程土体强度不足的难题,且大幅提前了工程进度. 相似文献
5.
The effect of turbulence on the nutrient flux towards osmotrophic cells is predicted to be size dependent. This should translate into growth. We experimentally followed and modelled the growth of two marine diatoms of different size (Thalassiosira pseudonana, 6 μm in diameter and Coscinodiscus sp., ca. 109 μm in diameter) under still water and turbulent conditions, using a shaker table. Experiments were done with phosphorus-limited cultures and lasted for ca. 5 days. Turbulence enhanced the growth of Coscinodiscus sp. in agreement with theory but not the growth of T. pseudonana, which was actually slightly lower under turbulence. At the end of the experiments there were about 1.7 times as many Coscinodiscus sp. cells in the turbulent treatment than in the still treatment, while for T. pseudonana almost the same cell concentration was found in both conditions. In addition, the Coscinodiscus sp. cells growing under still conditions presented a higher specific alkaline phosphatase activity than those growing in turbulence which indicates a higher need for phosphorus in the still cultures. A simple dynamic model, based on Michaelis–Menten nutrient uptake kinetics, needed nearly no optimisation other than using observed initial conditions of phosphate and cell concentrations. The model showed how an increased nutrient flux towards the cells translates non-linearly into cell growth, most likely by affecting the half-saturation constant (KM). However, since Coscinodiscus sp. experienced significant mortality and cells partially settled to the bottom of the containers, unequivocal support for the size-dependent effect of turbulence on nutrient uptake will require further experiments and more sophisticated modelling. The mechanisms to connect an increased nutrient flux towards cells with population growth and whether this process is size dependent are important in parameterizing the effects of turbulence on marine plankton in coupled physical–biological models. 相似文献