Microclimate modulation: An overlooked mechanism influencing the impact of plant diversity on ecosystem functioning

Abstract

Changes in climate and biodiversity are widely recognized as primary global change drivers of ecosystem structure and functioning, also affecting ecosystem services provided to human populations. Increasing plant diversity not only enhances ecosystem functioning and stability but also mitigates climate change effects and buffers extreme weather conditions, yet the underlying mechanisms remain largely unclear. Recent studies have shown that plant diversity can mitigate climate change (e.g. reduce temperature fluctuations or drought through microclimatic effects) in different compartments of the focal ecosystem, which as such may contribute to the effect of plant diversity on ecosystem properties and functioning. However, these potential plant diversity‐induced microclimate effects are not sufficiently understood. Here, we explored the consequences of climate modulation through microclimate modification by plant diversity for ecosystem functioning as a potential mechanism contributing to the widely documented biodiversity–ecosystem functioning (BEF) relationships, using a combination of theoretical and simulation approaches. We focused on a diverse set of response variables at various levels of integration ranging from ecosystem‐level carbon exchange to soil enzyme activity, including population dynamics and the activity of specific organisms. Here, we demonstrated that a vegetation layer composed of many plant species has the potential to influence ecosystem functioning and stability through the modification of microclimatic conditions, thus mitigating the negative impacts of climate extremes on ecosystem functioning. Integrating microclimatic processes (e.g. temperature, humidity and light modulation) as a mechanism contributing to the BEF relationships is a promising avenue to improve our understanding of the effects of climate change on ecosystem functioning and to better predict future ecosystem structure, functioning and services. In addition, microclimate management and monitoring should be seen as a potential tool by practitioners to adapt ecosystems to climate change.

Biodiversity and Climate Extremes: Known Interactions and Research Gaps

“…This process results in a higher evaporative demand, intensifying the heat/drought episode through what is known as the soil moisture-temperature feedback loop. The variety in plants' physiological responses becomes critical in moderating the severity of this feedback, thereby directly impacting human activities, especially agricultural productivity (Barriopedro et al, 2023;Beugnon et al, 2024;Graf et al, 2020;Miralles et al, 2019).…”

“…Biodiversity controls how ecosystems absorb pollutants, store carbon, or provide numerous natural resources. The regulation of water, gas, and energy fluxes, and the release and absorption of primary emitted particles (Fröhlich-Nowoisky et al, 2016;Sanaei et al, 2023) by functional and structural diversity and landscape heterogeneity, contributes to the regulation of land-surface climate feedbacks and can thereby affect local to global climate (Beugnon et al, 2024;Bonan, 2008;Duveiller et al, 2021;Graf et al, 2020;Miralles et al, 2019;Santanello et al, 2018;Ukkola et al, 2018).…”