Future no-analogue vegetation produced by no-analogue combinations of temperature and insolation
Projections of future climate change suggest that regional climates may evolve to states that are unlike any climate regime found on Earth today. These climates will impose novel constraints on plant species, and are likely to give rise to plant associations that are compositionally unlike any found on Earth today. Here, we explore whether the geographical distribution of previously mapped no-analogue climates corresponds to the geographical distribution of simulated no-analogue vegetation under scenarios of global warming.
We used JeDi, a process-based vegetation model that accounts for ecophysiological trade-offs in plant growth and survival, to identify the assembly of plant functional types into no-analogue associations under scenarios of global warming. We compared the geographical distribution of these no-analogue vegetation types with those of no-analogue climates derived from seasonal temperature and precipitation. To better understand the climatic causes that lead to no-analogue vegetation, we performed a set of JeDi simulation experiments and compared them, as well as selected climate indices, with the geographical distribution of no-analogue vegetation. Finally, we explored the changes in plant characteristics leading to no-analogue vegetation composition.
In our model simulations, a no-analogue vegetation type emerged in Northern Eurasia due to the interacting effects of rising temperatures and the prolongation of the growing season, combined with stable patterns in the seasonal insolation cycle. Future tropical biomes experiencing novel temperature and precipitation regimes however, resemble contemporary vegetation despite significant losses of plant diversity.
Our modelling study shows how no-analogue vegetation can emerge in response to novel climates produced by rising temperatures and stable insolation, while also suggesting that no-analogue climates do not necessarily lead to no-analogue vegetation types. This result underlines the importance of considering plant diversity and the need to integrate ecophysiological knowledge through process-orientated models when projecting future vegetation.