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首页> 外文期刊>Journal of Environmental Protection and Ecology >EXPLOITATION PATTERNS CALL FOR LIMITING THE SPRAT YIELD AT SUSTAINABLE LEVELS IN THE NORTH-WESTERN PART OF THE BLACK SEA
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EXPLOITATION PATTERNS CALL FOR LIMITING THE SPRAT YIELD AT SUSTAINABLE LEVELS IN THE NORTH-WESTERN PART OF THE BLACK SEA

机译：要求限制黑海西北部可持续水平的鱼鳞开采的开发模式

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摘要

Estimation of the optimum levels of exploitation for the sprat is based on using the structured and non-structured equilibrium models for the north-western part of the Black Sea. In the present paper, based on the concept of maximum sustainable yield (MSY), some sustainable yield curves have been created. It was found for the Black Sea sprat that yield per recruit curves does not reached the maximum value within the range of fishing mortality investigated. Medium confidence band shows that at fishing mortality rates around 0.8 the ratio yield and fishable biomass at unexploited level is around 0.25. It is seen from the year/recruit (Y/R) analysis that recruitment is unaffected regardless of how low spawning stock biomass (SSB) falls. It was clear that levels of fishing mortality that produces yield per recruit (Y/R) at or near the maximum will also reduce the spawing stock biomass (SSB) to levels that are a tiny fraction of its unexploited level. The value of F_(0.1) is arbitrary and thus, there is no guarantee that this is the proper management level for biological purposes (as a tonic for recruitment over fishing, for example) let alone when economic, social, and other environmental objectives are considered.
机译：对鲱鱼的最佳开采水平的估算是基于黑海西北部的结构化和非结构化平衡模型得出的。在本文中，基于最大可持续产量（MSY）的概念，已创建了一些可持续产量曲线。对于黑海西鲱，发现在调查的捕捞死亡率范围内，新兵的单产曲线未达到最大值。中置信度带显示，在捕捞死亡率约为0.8的情况下，未开发水平下的产量与可捕捞生物量之比约为0.25。从年度/招聘（Y / R）分析可以看出，无论产卵生物量（SSB）下降的多低，招聘都不会受到影响。显然，捕捞死亡率水平会导致新兵单产（Y / R）达到或接近最高水平，也将reduce养生物量（SSB）降至未利用水平的一小部分。 F_（0.1）的值是任意的，因此，不能保证这是出于生物学目的（例如，作为捕捞的补品）的适当管理水平，更不用说在实现经济，社会和其他环境目标时了考虑过的。

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