Frank Kenneth T, Petrie Brian, Shackell Nancy L, Choi Jae S
Ocean Sciences Division, Department of Fisheries and Oceans, Bedford Institute of Oceanography, PO Box 1006, Dartmouth, NS, Canada B2Y 4A2.
Ecol Lett. 2006 Oct;9(10):1096-105. doi: 10.1111/j.1461-0248.2006.00961.x.
The dependence of long-term fishery yields on primary productivity, largely based on cross-system comparisons and without reference to the potential dynamic character of this relationship, has long been considered strong evidence for bottom-up control in marine systems. We examined time series of intensive empirical observations from nine heavily exploited regions in the western North Atlantic and find evidence of spatial variance of trophic control. Top-down control dominated in northern areas, the dynamics evolved from bottom-up to top-down in an intermediate region, and bottom-up control governed the southern areas. A simplified, trophic control diagram was developed accounting for top-down and bottom-up forcing within a larger region whose base state dynamics are bottom-up and can accommodate time-varying dynamics. Species diversity and ocean temperature co-varied, being relatively high in southern areas and lower in the north, mirroring the shifting pattern of trophic control. A combination of compensatory population dynamics and accelerated demographic rates in southern areas seems to account for the greater stability of the predator species complex in this region.
长期渔业产量对初级生产力的依赖性，很大程度上基于跨系统比较且未考虑这种关系的潜在动态特征，长期以来一直被视为海洋系统中自下而上控制的有力证据。我们研究了北大西洋西部九个过度捕捞区域的密集实证观测时间序列，发现了营养控制空间差异的证据。自上而下的控制在北部地区占主导，在中间区域动态从自下而上演变为自上而下，而自下而上的控制则主导着南部地区。我们绘制了一个简化的营养控制图，该图考虑了一个更大区域内的自上而下和自下而上的驱动力，该区域的基础状态动态是自下而上的，并且能够适应随时间变化的动态。物种多样性和海洋温度共同变化，南部地区相对较高，北部较低，反映了营养控制的变化模式。南部地区补偿性种群动态和加速的人口统计学速率的结合似乎解释了该区域捕食者物种复合体更高的稳定性。
