  Range migrations in response to climate change, invasive species and the
emergence of novel ecosystems highlight the importance of temporal turnover in
community composition as a fundamental part of global change in the
Anthropocene. Temporal turnover is usually quantified using a variety of
metrics initially developed to capture spatial change. However, temporal
turnover is the consequence of unidirectional community dynamics resulting from
processes such as population growth, colonisation and local extinction. Here,
we develop a framework based on community dynamics, and propose a new temporal
turnover measure. A simulation study and an analysis of an estuarine fish
community both clearly demonstrate that our proposed turnover measure offers
additional insights relative to spatial-context-based metrics. Our approach
reveals whether community turnover is due to shifts in community composition or
in community abundance, and identifies the species and/or environmental factors
that are responsible for any change.
