Collaborative Research: Resource ratio effects on stream detritus and detritivores

生态系统的人为养分富集是一种全球现象，往往对生态群落产生负面影响，导致生物多样性降低。 营养素的增加会改变食物资源中碳和磷等营养元素的比例，并会影响生态系统中物种的多样性和类型。 许多水生物种已经进化到使用低质量的落叶作为食物资源（即，食草动物）;这些物种适应于具有相对于磷的高碳比的饮食。 当食物资源中的磷水平升高时，就像在人类富集的水生生态系统中经常发生的那样，一些食草动物物种的生长可能会受到负面影响，因为从体内消除过量磷的能量成本增加。 这种违反直觉的，对消费者增长的营养素升高的负面影响可能会导致水生生态系统中食草动物物种的损失。 该项目将确定碎屑资源中碳磷比例的变化是否会对Ozark高地溪流中富集梯度上的食虫昆虫物种的生长产生可预测的影响。 该研究将结合联合收割机实验室实验和对河流生态系统的区域数据集的分析，以确定人为的碎屑资源的磷富集是否对水生食草动物物种多样性产生直接的负面影响。 通过与流域团体和国家机构的联系，这项研究的结果将传达给当地社区和自然资源管理人员。 拟议的活动将支持研究生和本科生的研究培训和职业发展，包括代表性不足群体的成员。 该项目代表了来自一所研究型大学和一所本科大学的两名研究人员的合作。

Anthropogenic nutrient enrichment of ecosystems is a global phenomenon that often negatively affects ecological communities leading to lower biodiversity. Elevated nutrients can alter the proportion of nutritional elements such as carbon and phosphorus in food resources and can influence the diversity and type of species present in ecosystems. Many aquatic species have evolved to use low quality leaf litter as food resources (i.e., detritivores); these species are adapted to a diet that has a high ratio of carbon relative to phosphorus. When phosphorus levels in food resources are elevated, as is often the case in human-enriched aquatic ecosystems, the growth of some detritivore species may be negatively impacted due to an increased energetic cost of eliminating excess phosphorus from their bodies. This counter-intuitive, negative effect of elevated nutrients on consumer growth may lead to the loss of detritivore species from aquatic ecosystems. This project will determine whether changes in the ratio of carbon to phosphorus in detrital resources result in predictable effects on growth of insect detritivore species across an enrichment gradient in Ozark Highland streams. The research will combine laboratory experiments with an analysis of a regional data set on stream ecosystems to determine whether anthropogenic phosphorus enrichment of detrital resources is having direct negative effects on aquatic detritivore species diversity.Results from this project will provide a more thorough understanding of the ways that nutrient enrichment can impact stream systems, information that is useful to improved management of these ecosystems. Through outreach to watershed groups and state agencies, the results of this research will be communicated to the local community and natural resource managers. The proposed activity will support research training and career development of graduate and undergraduate students, including members of under-represented groups. This project represents a collaboration of two beginning investigators from a research university and a primarily undergraduate university.