《自然》[Nature]13年2月21日出版pdf全文

nero1981

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The fisheries industry around the world is in disarray. In some regions catches are stable and fishermen insist that all is well. Yet some researchers report fish numbers in dramatic decline and are calling for restrictions on fishing grounds. A central issue is the wisdom or otherwise of using estimates of the amount of fish hauled in by fishermen each year to assess the health of fisheries. In Comment this week we try to get to the facts. Daniel Pauly argues that catches, the only data available for many fisheries, are a crucial sign of the health of fish populations. Most fishermen today are catching fewer fish than their predecessors in the same waters. Catch data provide the information that researchers will need if they are to help reverse this trend. Ray Hilborn and Trevor Branch are not convinced. Many factors, not just abundance, determine the hauls of fishermen they say. Although important in terms of fisheries management, catch data alone cannot answer the question, how many fish are there in the sea? (Cover graphic: Denis Carrier).
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monk125

469787350

用户组级别不够，加油支持顶贴。。

nauticus

必须顶  

123456zsz

原来这样也可以  

biobio

谁都不容易啊 ~~  

MIYAGI

赚点分不容易啊  

杏花

谁能送我几分啊  

张佳

胚胎干细胞

foxok

世界上那些最容易的事情中，拖延时间最不费力。