Will among‐population variation in seed traits improve the chance of species persistence under climate change?

Abstract

Aim Seed traits related to recruitment have direct relevance for plant fitness and persistence. Trait variation in time and among populations may increase species resilience and ultimately reduce the risk of extinction. However, patterns of amongpopulation variation in critical recruitment traits remain poorly known and are often disregarded when considering extinction risk under future climates.Location Global. MethodsIn this paper we review and synthesize current knowledge about among-population variation in physiological and morphological traits related to plant recruitment. We outline the consequences of that variation for species persistence under climate change, and discuss the implications for conservation, management and restoration.Results The evaluated studies provide compelling evidence that amongpopulation variation in traits underpinning seedling emergence, growth and establishment is widespread. Contrary to expectations, environmental gradients do not appear to be reliable predictors of variation among populations and responses are often individualistic. Likewise, well-established cross-species patterns are not consistently reflected among populations within a species. As the pattern of this variation is unpredictable, we cannot make simple generalizations about how this variation is allocated across geographic ranges or the extent of environmental versus fixed genetic differences. Nor do these patterns clearly elucidate the potential for this variation to mitigate negative effects of climate change. Main conclusionsIf we ignore among-population variation in seed traits, or assume it will follow simple environmental clines, we do so at our own peril. The consequences of such an approach are likely to include biased forecasts of future range dynamics, hindering identification of the genetic material most appropriate for conservation, restoration and management. Further research that integrates ecology and emerging evolutionary genetic techniques to identify the distribution of seed traits within foundation species and the mechanisms driving them is urgently required to guide the management and maintenance of systems in the face of rapidly changing climates.

Inter- and intra-population variability in physical dormancy along a precipitation gradient

“…Furthermore, some studies have suggested that PY variability allows seeds to persist in variable environments (Ooi et al 2012;Fernández-Pascual et al 2013). However, there is scarce knowledge about the degree of PY variability, both among and within populations, especially in natural ecosystems (Cochrane et al 2015;Hudson et al 2015).…”

“…Moreover, most studies focused on PY variation among populations and individuals were performed in agricultural species, mainly in annuals and short-lived herbaceous perennials, but very few have dealt with woody species (Cochrane et al 2015;Hudson et al 2015). Vachellia aroma (Gillies ex Hook.…”

Seeds at the forefront: synthesis of the inaugural National Seed Science Forum and future directions in Australian seed science

“…Seeds are inherently plastic, with complexity of function apparent at any level (e.g. within and between species, plant populations, individual plants and seed populations) (Cochrane et al 2015b). Dormancy is a predominant trait in many floras, and complex dormancy is common in the Australian flora (Merritt et al 2007).…”

Inconclusive Predictions and Contradictions: A Lack of Consensus on Seed Germination Response to Climate Change at High Altitude and High Latitude

“…The suitable environment allows the persistence of those adapted species to germinate, grow, and reproduce, thus maintaining species abundance. However, this adaptation has been undergoing a rapid transformation in recent years, predominantly due to the effects of global warming bringing significant changes to climatic conditions [6,7]. It has been estimated that the earth's surface temperature has risen by 0.6 ∘ C over the past 100 years and the projections for future warming suggested an alarming 2 ∘ C in this century [8,9].…”