Warming and elevated CO 2 (eCO 2 ) are two potentially opposing climate‐carbon (C) feedback mechanisms that modulate the magnitude of the land C sink, with warming decreasing and eCO 2 increasing C sequestration. However, their net effect on soil organic C (SOC)—the largest terrestrial C stock—remains uncertain. Here, we quantify how warming, eCO 2 , and their interactions influence SOC by using 5558 paired observations from 1...

Climate forecasts project change not only in the mean of climate variables but also in their variance. If these dual changes interact, then future ecological dynamics will be difficult to predict using current experimental approaches, which typically change the mean or impose a single extreme event, such as drought. We designed a new field experiment to factorially reduce mean precipitation and increase its interannual variabi...

Forestation is a pivotal nature‐based strategy for enhancing soil organic carbon (SOC) sequestration, yet the differential impacts of pure versus mixed‐species plantations on SOC fractions and stability remain poorly quantified at a global scale. To address this knowledge gap, we performed a meta‐analysis of 4052 observations from 102 sites and showed that mixed forestation significantly increases SOC, particulate organic carb...

Global change ecology demands predictive models that reconcile data‐driven learning with mechanistic theory to address complex, interconnected ecosystem challenges. Traditional process‐based approaches struggle with spatiotemporal parameterization, while purely data‐driven machine learning approaches suffer from extrapolation, interpretability, and physical consistency. Knowledge‐guided machine learning (KGML) bridges this div...

The CO 2 ‐fertilisation effect (CFE) on vegetation productivity is the major driver of the enhanced land carbon sink in recent decades. CFE theoretically increases with elevation due to the higher sensitivity of carboxylation to an increase of CO 2 under lower CO 2 partial pressure, but the elevation‐dependent CFE pattern has been largely overlooked. By conducting a 6‐year CO 2 enrichment experiment (+100 ppm) in an alpine gra...

Understanding how extreme climate events reshape the temperature response of ecosystem respiration (Re) is critical for predicting carbon–climate feedbacks. Here, we combine observational data and land surface model simulations to investigate Re responses to heatwaves, focusing on temperature sensitivity ( Q 10 ) and thermal hysteresis. We develop a quantitative framework capturing hysteresis via temperature thresholds, their...

Aim Plastic responses of root productivity to precipitation changes would facilitate plant survival under drought stress. However, whether the responses are pervasive along the soil profile remains unknown. Here, we compiled a global dataset of root productivity at different soil depths from in situ precipitation manipulation experiments, and investigated whether the root productivity responded to precipitation changes uniform...

Aim Plant invasion is a major global environmental challenge. While invasive plants can potentially enhance soil nutrient availability by stimulating soil extracellular enzyme activities, empirical studies have yielded conflicting results. A comprehensive understanding of global patterns and underlying drivers is therefore essential for inferring generalities. Location Global. Time Period 2000–2025. Major Taxa Studied Invasive...

Aim Microbial carbon use efficiency ( CUE ) is one of the key indicators for the formation and release of soil carbon. CUE can be divided into exogenous CUE ( CUE ex , efficiency in using external carbon sources measured by e.g. 13 C or 14 C labeling) and endogenous CUE ( CUE en , efficiency in using internal carbon sources measured by 18 O labeling). Global changes strongly influence CUE, which response depends on the carbon...