Farrell A P
Department of Zoology and The Faculty of Land and Food Systems, University of British Columbia, 6270 University Blvd., Vancouver, BC, V6T 1Z4, Canada.
J Fish Biol. 2016 Jan;88(1):322-43. doi: 10.1111/jfb.12789. Epub 2015 Nov 22.
A major challenge for fish biologists in the 21st century is to predict the biotic effects of global climate change. With marked changes in biogeographic distribution already in evidence for a variety of aquatic animals, mechanistic explanations for these shifts are being sought, ones that then can be used as a foundation for predictive models of future climatic scenarios. One mechanistic explanation for the thermal performance of fishes that has gained some traction is the oxygen and capacity-limited thermal tolerance (OCLTT) hypothesis, which suggests that an aquatic organism's capacity to supply oxygen to tissues becomes limited when body temperature reaches extremes. Central to this hypothesis is an optimum temperature for absolute aerobic scope (AAS, loosely defined as the capacity to deliver oxygen to tissues beyond a basic need). On either side of this peak for AAS are pejus temperatures that define when AAS falls off and thereby reduces an animal's absolute capacity for activity. This article provides a brief perspective on the potential uses and limitations of some of the key physiological indicators related to aerobic scope in fishes. The intent is that practitioners who attempt predictive ecological applications can better recognize limitations and make better use of the OCLTT hypothesis and its underlying physiology.
21世纪鱼类生物学家面临的一项重大挑战是预测全球气候变化的生物影响。随着各种水生动物的生物地理分布已出现显著变化，人们正在寻找对这些变化的机理解释，以便为未来气候情景的预测模型奠定基础。关于鱼类热性能的一种机理解释已获得一定认可，即氧和容量限制热耐受性（OCLTT）假说，该假说认为当体温达到极端时，水生生物向组织供应氧气的能力会受到限制。这一假说的核心是绝对有氧范围（AAS，大致定义为向组织输送超出基本需求的氧气的能力）的最佳温度。在AAS峰值的两侧是劣化温度，它们定义了AAS何时下降，从而降低动物的绝对活动能力。本文简要介绍了与鱼类有氧范围相关的一些关键生理指标的潜在用途和局限性。目的是让尝试进行预测性生态应用的从业者能够更好地认识到局限性，并更好地利用OCLTT假说及其潜在生理学原理。
