Temporal stability versus community matrix measures of stability and the role of weak interactions

Relationships between different measures of stability are not well understood in part because empiricists and theoreticians tend to measure different aspects and most studies only explore a single form of stability. Using time-series data from experimental plankton communities, we compared temporal stability typically measured by empiricists (coefficient of variation of biomass) to stability measures typically measured by theoreticians derived from the community matrix (asymptotic resilience, initial resilience, and intrinsic stochastic invariability) using first-order multivariate autoregressive models (MAR). Community matrices were also used to derive estimates of interaction strengths between plankton groups. We found no relationship between temporal stability and stability measures derived from the community matrix. Weaker interaction strengths were generally associated with higher stability for community matrix measures of stability but were not consistently associated with higher temporal stability. Temporal stability and stability measures derived from the community matrix stability appear to represent different aspects of stability reflecting the multi-dimensionality of stability.

Methods
The field data were collected as described in Downing et al. 2014. The data were further processed as described in the associated Ecology Letters paper.

Literature cited:

Downing, A.L., Brown, B.L. & Leibold, M.A. (2014). Multiple diversity-stability mechanisms enhance population and community stability in aquatic food webs. Ecology, 95, 173–184.