Collaborative Research on the Effects of Plant Species and Functional Types on Diversity, Ecosystem Function, and Ecosystem Response to Perturbation in Arctic Tundra

University Of Alaska Fairbanks Campus, Fairbanks AK

Investigators

Abstract

Human activities are increasingly affecting earth's environment and ecosystems not only through direct impacts on climate and element cycling, but also by increasing the pace of introductions and extinctions of species. Because carbon and nutrients are cycled through the biosphere and plant species differ in traits that affect the rates of cycling of these elements, the abundance and diversity of species must affect ecosystem function. However, the extent to which individual plant species affect ecosystem function and the relationship between species diversity and ecosystem response to perturbation are still largely unknown. To what extent can plant species substitute for each other in ecosystem function? What key traits determine whether a plant species' effect on nutrient cycling can be substituted by other species? A field experiment in Alaskan tussock tundra will examine these questions by removing different combinations of plant species in the presence and absence of fertilization. The investigators will obtain a detailed picture of how interactions between plant species control how nutrients are redistributed under fertilization, because nutrients are a primary control over carbon storage in this highly nutrient-limited ecosystem. They will also track potential introductions of new species as plant community composition shifts because of the removals or fertilization. The results will help reveal how human-induced environmental perturbations may change the mechanisms controlling ecosystem carbon storage and plant species abundance and diversity. This is a collaborative project with Michelle Mack (DEB-0212749)