Linking stoichiometric homoeostasis with ecosystem structure, functioning and stability

Abstract

Ecosystem structure, functioning and stability have been a focus of ecological and environmental sciences during the past two decades. The mechanisms underlying their relationship, however, are not well understood. Based on comprehensive studies in Inner Mongolia grassland, here we show that species-level stoichiometric homoeostasis was consistently positively correlated with dominance and stability on both 2-year and 27-year temporal scales and across a 1200-km spatial transect. At the community level, stoichiometric homoeostasis was also positively correlated with ecosystem function and stability in most cases. Thus, homoeostatic species tend to have high and stable biomass; and ecosystems dominated by more homoeostatic species have higher productivity and greater stability. By modulating organism responses to key environmental drivers, stoichiometric homoeostasis appears to be a major mechanism responsible for the structure, functioning and stability of grassland ecosystems.

Leaf P increase outpaces leaf N in an Inner Mongolia grassland over 27 years

“…Different functional groups showed differential responses to long-term environmental changes, reflecting their different nutrient acquisition strategies [21]. The different plant N : P stoichiometry between our study and artificial N addition experiments indicates that conclusions drawn from studies of short-term N fertilization should be treated with caution when extrapolating to longer timescales.…”

Growth rate, protein:RNA ratio and stoichiometric homeostasis of submerged macrophytes under eutrophication stress

“…Yu et al (2011) and Xing et al (2015) made comparisons across vascular plants species in the Inner Mongolia grassland and across submerged macrophytes species in Yunnan plateau lakes, respectively. Yu et al (2010) reported that species with strong homeostasis are dominant and stable in the community, while ecosystems dominated by homeostatic taxa are productive and stable. In the study, stoichiometric homeostasis of V. natans was stronger than those of P. maackianus, M. spicatum and C. demersum, indicating V. natans is relatively dominant and stable in the community of aquatic plants under eutrophication stress.…”

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

“…For example, species H N and H N:P were positively correlated with species dominance and with temporal stability (i.e., biomass consistency over a specified time period (Lehman and Tilman 2000) -see "Materials and methods" section for calculation) on both shortterm and long-term temporal scales and across a large spatial scale in Inner Mongolian grasslands (Yu et al 2010). Furthermore, community H N was also positively correlated with community production and stability in most instances (Yu et al 2010). The most dominant species in a C 3 grassland in Wyoming, USA, had the highest H N:P , but in that case, there was no general correlation between species H N:P and species dominance (Dijkstra et al 2012).…”

“…Stoichiometric homeostasis is the degree to which an organism maintains relatively constant concentrations or ratios of elements within its tissues despite variation in the relative availabilities of these elements in its environment or food supply (Sterner and Elser 2002;Elser et al 2010;Yu et al 2010Yu et al , 2015. Stoichiometric homeostasis theory has been investigated and validated primarily in marine and freshwater ecosystems (Frost et al 2002(Frost et al , 2005Demars and Edwards 2007).…”

“…Only three studies have attempted to relate stoichiometric homeostasis with vascular species and (or) terrestrial ecosystem stability, dominance, and production, and all of those were conducted in temperate grasslands (Yu et al 2010(Yu et al , 2015Dijkstra et al 2012). For example, species H N and H N:P were positively correlated with species dominance and with temporal stability (i.e., biomass consistency over a specified time period (Lehman and Tilman 2000) -see "Materials and methods" section for calculation) on both shortterm and long-term temporal scales and across a large spatial scale in Inner Mongolian grasslands (Yu et al 2010). Furthermore, community H N was also positively correlated with community production and stability in most instances (Yu et al 2010).…”