Collaborative Research: Environmental Variability, Functional Redundancy, and the Maintenance of Ecological Processes: Experiments in a Model Ecosystem

物种的功能特征是那些决定物种对环境条件的特定反应或它们对生态过程的影响的特征。目前的理论表明，具有许多物种的群落以相似的方式执行给定的功能，但对环境条件具有不同的敏感性，将表现出更大的生态系统属性的时间稳定性。所谓的功能冗余应该导致物种之间的补偿，因为当另一些物种对环境变化的反应较差时，一些物种会做得更好。人为的全球变暖是当前和预期的种群动态、物种相互作用和群落结构从局部到全球范围内变化的主要驱动因素。因此，由此导致的生物多样性变化有可能显著改变重要的生态系统属性，如生产力、养分循环和对干扰或入侵的抵抗力。虽然生态学家通常强调人口和社区对气候平均值变化(例如，气温和降雨量的增加)的反应，但全球环流模型也预测，世界许多地区极端天气和气候事件的强度、频率和持续时间将显著增加；也就是说，自然环境的变异性增加。不幸的是，我们目前对气候变化加剧对自然生态系统的影响的了解通常相当贫乏。因此，预测群落将如何应对不断变化的环境变异性被认为是一个关键的研究优先事项。智力价值这个项目将促进我们对预测的温度变异性变化将如何影响岩石海岸上关键类群的行为、人口统计学和相互作用的理解？用田间试验检验理论生态预测的模型系统。环境温度强烈地影响着大多数生物的生理、行为和人口统计学，平均温度的变化已经与许多物种的地理范围转移有关。将使用一种新的操纵技术来测试热变率的变化对同类放牧帽贝的性能的影响，它们底栖微藻食物的生产力，以及由此产生的两个分类群之间的相互作用强度。营养水平之间的能量转移是一个关键的生态系统过程，与当地食物网的支持和营养循环的速度有关。这项研究不仅将评估热变异性对帽贝生存、生长和放牧活动的特定物种的影响，还将评估随着环境变异性的增加，帽贝物种之间的功能冗余以随时间保持生态系统功能的可能性。这项研究产生的数据将为未来在这个多样化和多产的栖息地调查气候变化的后果提供一个框架。广泛影响该项目将显著加强加州州立大学长滩分校(CSULB)的研究和教育基础设施--这是一所服务于少数族裔(西班牙裔)、以本科生为主的机构。在三年的资助中，至少有两名来自南加州大学的硕士研究生和12名本科生将参与这项研究。每个学生都将在暑假期间在霍普金斯海洋站生活和工作10周，获得密集的动手研究经验。该项目还将为斯坦福大学的一名博士后科学家提供培训，该科学家将通过积极参与拟定和实施拟议研究的所有方面来获得研究经验和熟练程度。两位PI都特别致力于为女性和传统上在科学界代表性较低的少数族裔提供研究经验和机会：丹尼目前的三名学生中有一名是女性，在艾伦实验室工作的四名本科生中，有三名是女性，一名是路易斯·斯托克斯少数族裔参与联盟(LSAMP)的研究员。LSAMP计划(部分由NSF资助)旨在提高成功完成科学、技术、工程和数学(STEM)学士学位课程的代表人数不足的学生的质量和数量，并增加对研究生学习感兴趣、有学术资格并被录取的学生数量。丹尼将使用这个项目的数据和洞察力，作为他每年在海洋发现研究所(以前的水上探险)运营的密集夏季实地考察项目中教授的为期一周的“生物力学模块”的一部分。这项计划(部分由国家科学基金会资助)旨在吸引圣地亚哥市中心的高中生对科学感兴趣，并为他们提供进入四年制大学所需的技能。

Functional traits of species are those that determine either species-specific responses to environmental conditions or their influence on ecological processes. Current theory suggests that communities with many species that perform a given function in a similar way but have different sensitivities to environmental conditions will exhibit greater temporal stability of ecosystem properties. So-called functional redundancy should lead to compensation among species, as some will do better when others do worse in response to environmental variability. Anthropogenic global warming is a major driver of current and anticipated changes in population dynamics, species interactions, and community structure from local to global scales. Resulting changes in biodiversity therefore have the potential to significantly alter important ecosystem properties such as productivity, nutrient cycling, and resistance to disturbance or invasion. Although ecologists have typically emphasized the response of populations and communities to changing climatic averages (e.g., increasing temperature and rainfall), global circulation models also predict significant increases in the intensity, frequency and duration of extreme weather and climate events in many parts of the world; that is, increases in the variability of the physical environment. Unfortunately, our current knowledge about the effects of increasing climatic variation on natural ecosystems is generally quite poor. Predicting how communities will likely respond to changing environmental variability has therefore been recognized as a critical research priority.Intellectual MeritThis project will advance our understanding of how projected changes in temperature variability will affect the behavior, demography, and interactions of key taxa on rocky shores ? a model system for testing theoretical ecological predictions with field experiments. Environmental temperatures strongly influence the physiology, behavior, and demography of most organisms, and changes in average temperature have already been implicated in geographic range shifts of many species. A novel manipulative technique will be used to test the effects of changes in thermal variability on performance by a guild of congeneric grazing limpets, the productivity of their benthic microalgal food, and the resulting interaction strengths between the two taxa. Energy transfer among trophic levels is a key ecosystem process linked to local food-web support and rates of nutrient cycling. This research will evaluate not only species-specific effects of thermal variability on limpet survival, growth, and grazing activity, but also the potential for functional redundancy among limpet species to maintain that ecosystem function over time as environmental variability increases. Data generated from this study will provide a framework for future investigations of the consequences of climate change in this diverse and productive habitat.Broader ImpactsThis project will significantly enhance the infrastructure of research and education at California State University, Long Beach (CSULB) - a minority (Hispanic) serving, predominantly undergraduate institution. At least two master's students and twelve undergraduates from CSULB will participate in this study over the three years of funding. Each student will spend ten weeks living and working during the summer at Hopkins Marine Station, gaining an intensive hands-on research experience. This project will also provide training for a postdoctoral scientist at Stanford University, who will gain research experience and proficiency by actively participating in the development and implementation of all aspects of the proposed study. Both PIs are especially committed to providing research experiences and opportunities to women and minorities traditionally underrepresented in science: one of Denny's current three students is a woman, and of the four undergraduate students working in Allen's lab, three are women and one is a Louis Stokes Alliance for Minority Participation (LSAMP) Research Fellow. The LSAMP program (funded in part by NSF) is designed to increase the quality and quantity of underrepresented students successfully completing science, technology, engineering and mathematics (STEM) baccalaureate degree programs, and to increase the number of students interested in, academically qualified for, and matriculated into programs of graduate study. Denny will use data and insight from this project as part of a week-long "biomechanics module" he teaches annually in an intensive summer field program run by the Ocean Discovery Institute (formerly Aquatic Adventures). This program (also funded in part by NSF) seeks to interest inner-city high school students from San Diego in science, and to provide them with the skills needed to gain access to 4-year colleges.