Stoichiometric homeostasis: a test to predict tundra vascular plant species and community-level responses to climate change

Arctic Science

article

Qian Gu¹  Tara J. Zamin²  Paul Grogan¹ 

[1] Department of Biology, Queen’s University;School of Biological Sciences, Monash University

关键词: Arctic tundra;    nitrogen;    phosphorus;    species dominance;    spatial stability.;   

DOI  :  10.1139/as-2016-0032

学科分类：地球科学(综合)

来源: NRC Research Press

【 摘 要 】

Climate change is having profound influences on Arctic tundra plant composition, community dynamics, and ecosystem processes. Stoichiometric homeostasis ( H ), the degree to which a plant maintains its internal nutrient concentrations independent of nutrient variations in its environment, may be a useful approach to predict the impacts of these influences. In this case study, we used fertilization manipulation data to calculate homeostasis indices based on nitrogen ( H N ), phosphorus ( H P ), and nitrogen to phosphorus ratios ( H N:P ) of aboveground tissues for seven common tundra vascular species belonging to three growth forms. We then analyzed species H relationships with dominance, spatial stability, and responsiveness to various experimental manipulations. Each of the H indices was correlated amongst tissue types within each species and was generally highest in ericoid mycorrhizal host species and lowest in the ectomycorrhizal birch. Species H P and H N:P were consistently positively correlated with aboveground biomass within the controls and across all manipulations. Furthermore, these same species were spatially stable across experimentally warmed field plots. Stoichiometric homeostasis theory has been successful in predicting grassland community dynamics. This first test of its applicability across a variety of Arctic plant growth forms highlights its considerable potential in predicting tundra plant community structure and responses to environmental change.

【 授权许可】

CC BY