Inter- and intraspecific variability in the responses of grassland plants to winter climate change
Final Report Abstract
Winter climate change is a complex phenomenon, with snow depth, soil freezing dynamics, and variable air temperatures all interacting to bring about differences in among‐ and within‐species growth responses. The objective here was to detect growth differences in the responses of species, ecotypes, and plant functional groups to winter processes impacted by warmer temperatures. Therefore, experiments were carried out simulating cold acclimation, winter warming, deacclimation, dormancy loss, and frost tolerance. Among‐species variation was then compared to within‐species variation. Five different experiments were conducted to answer two main questions: (1) what generalities can be found among species‐ and ecotype‐specific plant responses to winter warming under different environmental conditions and (2) what is the role of within species variation in predicting plant responses to climate warming? Generalities were found among species (relating dormancy depth and its rate of decrease) and within species (latitudinal grass ecotypes showed similar north‐south cold acclimation patterns as previously shown for tree species). Sensitivity to changes in photoperiod was found to influence the temperature‐tracking abilities of tree species and grass ecotypes. Photoperiod sensitivity is therefore an important characteristic of plants related to the ability to extend the growing season and resume growth during sudden midwinter warm spells. Within species variation in stress response being equal to among‐species variation is a novel finding which implies that treating a species as a uniform unit across its distribution in terms of its responsiveness to climate change is dubious. Further implications are (1) assisted migration not only of species but also of better adapted ecotypes remains to be tested, (2) species distribution models will profit from incorporating within‐species variation, (3) biodiversity conservation has to go beyond protection of species. A better understanding of the evolution of ecotypes and local adaptations and direct tests of the resilience of communities composed of different ecotypes rather than different species will in the future advance our abilities to understand potential effects of climate change and cope with them in a sustainable manner.
Publications
- (2014) Relative effects of temperature vs. photoperiod on growth and cold acclimation of northern and southern ecotypes of the grass Arrhenatherum elatius. Environmental and Experimental Botany 106: 189‐196
Malyshev AV, Henry HAL, Kreyling J
(See online at https://doi.org/10.1016/j.envexpbot.2014.02.007) - (2015) Plant responses to climatic extremes: within‐species variation equals among‐species variation. Global Change Biology
Malyshev AV, Beierkuhnlein C, Henry HAL, Jentsch A, Arfin Khan MAS, Steinbauer MJ, Dengler J, Willner E, Kreyling J
(See online at https://doi.org/10.1111/gcb.13114)
