Recent advances in ecological stoichiometry: insights for population and community ecology

39.Conventional theories of population and community dynamics are based on a singlecurrency such as number of individuals, biomass, carbon or energy. However,organisms are constructed of multiple elements and often require them (in particularcarbon, phosphorus and nitrogen) in different ratios than provided by their resources;this mismatch may constrain the net transfer of energy and elements through trophiclevels. Ecological stoichiometry, the study of the balance of elements in ecologicalprocesses, offers a framework for exploring ecological effects of such constraints. Wereview recent theoretical and empirical studies that have considered how stoichiometrymay affect population and community dynamics. These studies show thatstoichiometric constraints can affect several properties of populations (e.g. stability,oscillations, consumer extinction) and communities (e.g. coexistence of competitors,competitive interactions between different guilds). We highlight gaps in generalknowledge and focus on areas of population and community ecology whereincorporation of stoichiometric constraints may be particularly fruitful, such asstudies of demographic bottlenecks, spatial processes, and multi-species interactions.Finally, we suggest promising directions for new research by recommending potentialstudy systems (terrestrial insects, detritivory-based webs, soil communities) to improveour understanding of populations and communities. Our conclusion is that a betterintegration of stoichiometric principles and other theoretical approaches in ecologymay allow for a richer understanding of both population and community structure anddynamics.S. J. Moe, Norwegian Inst. for Water Research, NO-0411 Oslo, Norway (jannicke.moe@niva.no) and Centre for Ecological and Evolutionary Synthesis (CEES), Univ.ofOslo, NO-0316 Oslo, Norway.