Ecological Stoichiometry

Ecological stoichiometry – the ratio of elements in organisms and ecosystems – links the biological processes of organisms to their environment’s chemical composition. Understanding the extent and controls of stoichiometric flexibility at both the organismal and community level is important because global change factors (such as increasing nutrient deposition) can affect ecological stoichiometry and thus ecosystem functions. Using a meta-analysis framework, our group characterized how organisms, communities, and ecosystems respond to global change factors such as nutrient enrichment. We found that organisms with high baseline nutrient concentrations or those living in nutrient-rich environments tend to exhibit lower stoichiometric flexibility. Our current project is focused on investigating how climatic and biotic factors mediate stoichiometric responses to nutrient perturbation. Given the tight link between ecological stoichiometry and many important global processes such as carbon sequestration and element cycling, a more comprehensive understanding of stoichiometric flexibility will allow us to better predict how natural systems will respond to growing global change pressures.

This work is recently funded on a new DOE grant to apply the SCAMPS model to a temperate forest system!

Sistla, S., A. Appling, A. Lewandowska, B. Taylor, A. Wolf. Stoichiometric Flexibility in Response to Fertilization along Gradients of Environmental and Organismal Nutrient Richness. Oikos doi: 10.1111/oik.02385.

Sistla, S., E. Rastetter, J. Schimel. Responses of a tundra system to warming using SCAMPS: A stoichiometrically coupled, acclimating microbe-plant-soil model. Ecological Monographs 84 (1): 151 – 170.

Han, X., S. Sistla, X. Lü, Y. Zhang, X.G. Han. Hierarchical responses of plant stoichiometry to nitrogen deposition and mowing in a temperate steppe. Plant and Soil 382: 175 – 187.   

Sistla, S. and J. Schimel. Stoichiometric flexibility as a regulator of carbon and nutrient cycling in terrestrial ecosystems under change. New Phytologist 96 (1): 68 – 78.