Contrasting thermophilization among forests, grasslands and alpine summits

Area of Science:

• Ecology
• Climate Change Biology
• Biodiversity Research

Background:

• Climate warming alters species composition, favoring warmth-demanding species over cold-adapted ones (thermophilization).
• Biodiversity responses to climate change often lag, leading to accumulating climatic debts in ecosystems.
• Standardized quantification of thermophilization and climatic debts across diverse European habitats is lacking.

Purpose of the Study:

• To quantify thermophilization and climatic debts across European forests, grasslands, and alpine summits.
• To investigate variations in thermophilization trajectories and debt accumulation among different ecosystems.
• To identify mechanisms driving differential responses of plant communities to climate warming.

Main Methods:

• Analysis of multidecadal vegetation data from 6,067 resurveyed plots across Europe.
• Long-term monitoring spanning 12-78 years in forests, grasslands, and alpine summit habitats.
• Statistical assessment of thermophilization trends and climatic debt accumulation in relation to temperature changes.

Main Results:

• Forest understory and grassland plant communities showed positive but non-significant thermophilization.
• Alpine summit vegetation exhibited significantly stronger thermophilization (up to five times).
• Climatic debts accumulated in forests and alpine summits, correlating positively with macroclimate temperature changes, while grasslands showed less debt.

Conclusions:

• Plant communities exhibit divergent thermophilization trajectories and increasing climatic debts across different European ecosystems.
• Alpine summits are particularly vulnerable to climate warming, showing pronounced thermophilization and debt.
• Understanding ecosystem-specific responses is crucial for projecting future biodiversity shifts under accelerating climate change.