Forest Age and Management Measures Regulate the Responses of Forest Ecosystem to Drought

We thank Li et al. (2025) for emphasizing the role of forest age in the responses of plantations to drought. Although forest age was included in our analysis, canopy height emerged as a stronger predictor (Ma et al. 2025). Yet tree height or diameter at breast height does not always track chronological age (Au et al. 2022). Indeed, several studies suggest that tree age may be more relevant than height in addressing global change, as older trees store more carbon in biomass and retain it as a carbon sink for longer periods than fast-growing younger trees (Piovesan and Biondi 2021). However, the worldwide loss of old trees and reforestation dominated by young, even-aged stands (Lindenmayer et al. 2012) makes it a critical research priority to quantify how tree age modulates responses of forest ecosystems to drought.

A global tree-ring synthesis of more than 20,000 trees showed that younger, canopy-dominant trees suffer greater drought-induced growth reductions but recover more quickly after drought (Au et al. 2022). However, forest management can modulate drought responses by altering age structure, species composition, and canopy density (Manrique-Alba et al. 2022; Liu et al. 2022). Our study finds that plantations are more vulnerable to drought (Ma et al. 2025), but this does not preclude the potential for tree diversity and management practices to mitigate drought impacts. Diverse forest structures and targeted management enhance resistance (Liu et al. 2022). However, these effects are spatially heterogeneous and species-specific, and are constrained by stand characteristics (e.g., age, height) and site conditions (e.g., climate, soil nutrients) (Manrique-Alba et al. 2022; Li et al. 2020) (Figure 1). Our study reveals a temporal trade-off between drought resistance and resilience in plantations (Ma et al. 2025), likely driven by legacy effects of early-stage management on subsequent drought responses. Therefore, assessing forest drought responses requires considering tree age and how management enhances plantation resilience by optimizing stand structure and resource allocation.

Key methods for assessing the responses of forest ecosystems to drought include dendrochronology, forest inventories, and remote sensing (Figure 1). Remote sensing enables real-time monitoring of ecosystem water status and growth dynamics through vegetation indices (NDVI, EVI), surface temperature, and canopy moisture, and also captures drought-induced physiological and structural changes across spatiotemporal scales (Tian et al. 2018; Vicente-Serrano et al. 2013). Tree-ring width, by contrast, which directly reflects variations in radial growth, provides a quantitative measure of growth response to drought at the individual tree scale (Gazol et al. 2018; Vicente-Serrano et al. 2013). Unfortunately, matched datasets of tree rings from plantations and natural forests remain scarce. Although local forest inventories can partly fill this data gap, their discontinuous time series limit assessments of long-term drought effects. To enhance the ecological stability of plantations under climate change, we propose a multi-scale, multi-metric framework integrating remote sensing, field observations, and tree-ring data, with explicit consideration of stand age, tree height, species composition, biodiversity, and management practices (Figure 1). This approach supports mechanistic understanding of drought responses and informs targeted afforestation and adaptation strategies.

Longlong Ma: conceptualization, writing – review and editing. Jun Ma: writing – review and editing. Pu Yan: writing – original draft. Feng Tian: writing – original draft, writing – review and editing. Zhenhong Hu: conceptualization, writing – review and editing.

The authors declare no conflicts of interest.

This article is a Response to a Letter to the Editor by Li et al., https://doi.org/10.1111/gcb.70509 regarding Ma et al., https://doi.org/10.1111/gcb.70055.