Collaborative Research: GLOBEC-01: Patterns of Energy Flow and Utilization on Georges Bank

该项目基于US-GLOBEC在西北大西洋的研究，综合了生产和能源流动的关键方面，并利用来自其他来源的关于食物网上下级生产过程的信息来补充US-GLOBEC数据。主要目标是研究GLOBEC和GLOBEC相关研究的几个备选模型结果，这些研究有助于解决一些悬而未决的问题，并重新审视乔治滩的能源流动模式。本研究加强并扩展了之前的研究结果，明确考虑了该系统早期模型中未考虑的因素，包括：(1)微生物食物网，(2)考虑新的和循环的初级生产，(3)乔治滩初级和次级生产的空间异质性，(4)高营养水平生物量和产量的变化，以及(5)环境强迫对生产过程的影响。将这些元素纳入建模工作可以更详细地了解世行的生产过程。前四个要素提供了更广泛的生态系统背景，而最后一个要素提供了与美国- globec项目之一的链接。美国的主要主题是气候变化。后一个问题是通过比较反映不同环境和鱼类群落制度的几个不同的十年尺度时间段来解决的：(1)1960年代冷，其特点是远洋船队捕捞了丰富的底栖鱼类；(2) 20世纪70年代，水温“平均”，国内捕捞量增加，底栖鱼类资源枯竭；(3) 20世纪80年代，以水温“平均”、底栖鱼类资源过度捕捞和板鳃类增加为特征；(4) 90年代“平均”温度、盐度较低，以捕捞死亡率降低、底栖鱼类种群重建、板鳃类和远洋鱼类增加为特征。由于过度捕捞造成鱼类群落结构的大规模变化，如果不考虑其他生态系统组成部分的变化，就无法充分了解目标物种的种群动态。正在制订个别模型网络，以代表上述每一个时期。随后，将开发动态建模来描述这些制度之间的转换或转移。

This project synthesizes key aspects of production and energy flow, based on US-GLOBEC studies in the Northwest Atlantic, and augment the US-GLOBEC data with information from other sources on production processes at the lower and upper levels of the food web. The primary objectives examine several alternate model outcomes of GLOBEC and GLOBEC-related studies that help address a number of outstanding issues and re-examine patterns of energy flow on Georges Bank. This research enhances and expands the findings of previous investigations, with explicit consideration of factors not addressed in earlier models of this system including: (1) the microbial food web, (2) consideration of new and recycled primary production, (3) spatial heterogeneity of primary and secondary production on Georges Bank, (4) changes in biomass and production at higher trophic levels, and (5) the effects of environmental forcing on production processes. Incorporation of these elements into the modeling effort permits a more detailed understanding of production processes on the Bank. The first four elements provides the broader ecosystem context, while the last provides the link to one of the US-GLOBEC program.s principal themes, climate change. The latter is being addressed by comparing several different decadal-scale time periods that reflect differing environmental and fish community regimes: (1) the cold 1960s characterized by abundant groundfish stocks fished by distant water fleets; (2) the 1970s, characterized by "average" water temperatures, increased domestic fishing effort, and depletion of groundfish stocks; (3) the 1980s, characterized by "average" water temperatures, overfishing of groundfish stocks, and increases in elasmobranchs; and (4) the "average" temperature, lower salinity 1990s, characterized by reduced fishing mortality, rebuilding of groundfish stocks, and increases in elasmobranchs and pelagic fish. Because of large-scale changes in the fish community structure as a result of over-exploitation, a full understanding of the population dynamics of the target species will not be attained without consideration of changes in other ecosystem components. Individual model networks are being formulated to represent each of the above periods. Subsequently, dynamic modeling will be developed to describe the transformations or shifts between these regimes.