Effects of Temperature on Phytoplankton Growth Rates

温度是控制极地系统中许多过程的基本变量，但令人惊讶的是，很少有人试图综合温度对称为浮游植物的单细胞生物生长的影响。 由于浮游植物是所有海洋食物网的基础，它们在海洋生态中起着至关重要的作用。 许多全球模型使用一种简单的关系，将温度对浮游植物生长的影响从较暖的沃茨推断为极地温度，但这在模型结果中引入了很大的不确定性。本项目将研究在极地系统中遇到的低温下温度对生长的影响。 此外，考虑到未来预期的潜在海洋变化，它将允许更准确地预测未来对这种变化的反应。该项目还将进一步推动NSF培养新一代科学家和向公众提供科学发现的目标。该项目将涉及一名研究生在实地考察和本科生在国内机构的研究活动。这项工作的结果将纳入一门新的本科课程，研究人员将通过一般性讲座和其他外联活动让公众参与进来。温度是所有生态系统的基本变量，也是极地系统唯一最重要的划界特征。 它也可能受到气候变化的影响;事实上，在过去的半个世纪里，南极的一些（但不是全部）地区经历了显著的大气变暖。 尽管温度对生物系统有着明显而深刻的影响，但几乎所有的模型都使用来自较暖温度的温度-生长速率公式。 浮游植物光合作用的模拟估计可能会低估这些速率高达60%，如果生长速率被低估了这种温度浮游植物的生长关系。如果是这样的话，这可能对温度变化对海洋生产力影响的区域和全球模型产生深远影响。为了解决这一不确定性，该项目将量化在南极遇到的温度（低于4摄氏度）下浮游植物最大生长率与温度的关系。 从南极沃茨分离出的浮游植物将用于旨在评估南极若干种类浮游植物最大生长率的实验。将进行温度扰动实验，以评估南极浮游植物在生长期间适应温度升高后对一系列温度的反应。

Temperature is a fundamental variable controlling many processes in polar systems, but surprisingly few attempts to synthesize the effects of temperature on the growth of single-celled organisms called phytoplankton have been made. Because phytoplankton are the base of all marine food webs, they play an essential role in the ocean's ecology. Many global models use a simple relationship that extrapolate the effects of temperature on phytoplankton growth derived from warmer waters to polar temperatures, but this introduces substantial uncertainties in the models' results. This project will investigate the effects of temperature on growth at the low temperatures encountered in polar systems. Furthermore, given the potential oceanic changes expected in the future, it will allow much more accurate predictions of future responses to this change. The project will also further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. The project will involve a graduate student in the fieldwork and undergraduates in research activities at the home institution. Results from the work will be incorporated into a new undergraduate course and the researchers will involve the public through general lectures and other outreach activities. Temperature is a fundamental variable in all ecosystems, and is the single most important delimiting feature of polar systems. It is also likely to be influenced by climate change; indeed, some (but not all) regions in the Antarctic have experienced significant atmospheric warming in the past half century. Despite the clear and profound influence of temperature of biological systems, nearly all models use a temperature-growth rate formulation derived from warmer temperatures. Modeled estimates of phytoplankton photosynthesis may underestimate these rates by up to 60% if the growth rate is underestimated by this temperature-phytoplankton growth relationship. If so, this could have profound impacts on regional and global models of the impacts of temperature change on oceanic productivity. To address this uncertainty, this project will quantify the phytoplankton maximum growth rate-temperature relationship at temperatures encountered in the Antarctic (less than 4 degrees C). Phytoplankton isolated from Antarctic waters will be used in experiments designed to assess the maximum growth rates of a number of types of phytoplankton that occur in the Antarctic. Temperature perturbation experiments will be performed to assess the response of Antarctic phytoplankton to a range of temperatures after having been acclimated to increased temperatures during growth.