Mobile Field Respirometry System for Evaluating Effects of Environmental Stressors on Fish Performance

人类活动造成的生物多样性丧失是一个重要而紧迫的科学问题。因此，提高我们理解和预测环境压力对性能和健身特征的影响的能力变得越来越重要。缺氧（低溶解氧，DO）是人类对淡水和沿海沃茨造成的最严重的压力表现之一，这种压力是由加速富营养化的废物和肥料的流入驱动的。而且，对于鱼类来说，严重的缺氧可能是一个强大的限制因素，对健身相关的性能（例如，游泳）。气候变暖可能会加剧缺氧，因为氧气在水中的溶解度随着温度的升高而降低，而鱼类等外温动物（冷血生物）的新陈代谢增加。缺氧也可能加剧热应激的影响，限制鱼类在高温下的有氧性能。鉴于缺氧和全球变暖都是普遍存在的水生压力，解决其相互作用的影响至关重要。这对热带鱼尤其重要，其中许多对发展中国家的粮食安全至关重要，而且由于热窗狭窄，可能对气候变暖特别敏感。移动的呼吸测定实验室（MRL）提供了一个独特的机会，进行标准化的“现场”措施的鱼类性能和耐热性在多个物种和多个地点确定从我们的长期（24年）数据库的DO和温度的水生网站在乌干达，东非。MRL将使我们的研究计划更上一层楼，使我们能够在多个鱼类谱系中寻找对两种普遍压力源的平行（和独特）反应模式。MRL是一种现场兼容系统，集成了Loligo Systems（http：//www.example.com）提供的呼吸测量设备和软件，安装在一辆四轮驱动皮卡车中，带有硬化（安全）顶盖和随附的便携式户外外壳。www.loligosystems.com该系统使用便携式太阳能电池板，场发生器和电池驱动的泵运行，将使我们能够在偏远地区检测鱼类，为鱼类对环境压力的反应进行更广泛和有代表性的分析打开大门。实验将使用急性暴露和热适应的组合来量化标准和静息代谢率、临界氧张力和临界热最大值的温度敏感性和短期适应能力。我们将针对一套跨越广泛环境梯度的遗传学上遥远的鱼类物种，包括对该地区粮食安全至关重要的鱼类。MRL将促进国内和国际的合作和培训;我们估计，每年将有1名PDF，1-2名研究生，1- 2名本科生和1名研究助理使用该系统，从而有助于每年培训多达6名HQP。

Biodiversity loss in response to human activities is a critical and compelling scientific issue. It has thus become increasingly important to advance our ability to understand and predict effects of environmental stressors on performance and fitness traits. Hypoxia (low dissolved oxygen, DO) is one of the most serious manifestations of anthropogenic stress to fresh and coastal waters driven by influxes of wastes and fertilizers that accelerate eutrophication. And, for fish, severe hypoxia can be a powerful limiting factor on fitness-related performance (e.g., swimming). Climate warming may exacerbate hypoxia, because the solubility of oxygen in water decreases with rising temperature, while the metabolism of ectotherms (cold-blooded organisms) like fish increases. Hypoxia may also exacerbate effects of thermal stress by limiting aerobic performance of fish at higher temperatures. Given that hypoxia and global warming are both pervasive aquatic stressors, it is critical to address their interactive effects. This is particularly important in tropical fishes, many of which are critical to food security in the developing world, and may be particularly sensitive to climate warming given narrow thermal windows. The Mobile Respirometry Lab (MRL) offers a unique opportunity to carry out standardized “on-site” measures of fish performance and thermal tolerance across multiple species and multiple locations identified from our long-term (24-yr) data base of DO and temperature for aquatic sites in Uganda, East Africa. The MRL will move our research programs to the next level by allowing us to look for parallel (and unique) patterns of response to two pervasive stressors across multiple fish lineages. The MRL is a field-compatible system that integrates respirometry equipment and software provided by Loligo Systems (http://www.loligosystems.com) housed in a 4-wheel drive pick-up with a hardened (secure) canopy cover and an accompanying portable outdoor enclosure. This system, run using portable solar panels, a field generator, and battery-operated pumps will allow us to assay fish at remote sites, opening the door for a more widespread and representative analysis of fish response to environmental stressors. Experiments will quantify temperature sensitivity and short-term acclimation capacity of standard and resting metabolic rate, critical oxygen tension, and critical thermal maximum using a combination of acute exposures and thermal acclimations. We will target a suite of phylogenetically distant fish species across broad environmental gradients including fishes critical to food security in the region. The MRL will facilitate collaboration and training both nationally and internationally; and we estimate that each year this system will be used by 1 PDF, 1-2 graduate students, and 1-2 undergraduates, and a research assistant, thus contributing to the training of up to 6 HQP per year.