Global Change Biology最新文献

Ecosystem carbon dynamics are governed by complex temporal dependencies and environmental interactions, yet these processes remain poorly understood and quantified across diverse biomes. Here, we developed an explainable LSTM-Attention framework that integrates LSTM networks, attention mechanisms, and gradient-based attribution methods to reveal temporal dependencies in ecosystem carbon flux responses by analyzing eddy covariance flux measurements from 71 sites spanning eight North American biomes. Using this approach, we identified three distinct temporal memory patterns governing carbon flux responses. Grasslands exhibit short-term memory dominance with exponentially increasing temporal contributions from distant to recent past. Deciduous broadleaf forests and wetlands show long-term memory dominance, with deciduous broadleaf forests displaying the strongest historical dependence (attribution values declining from 0.30 at 6 months to 0.045 at 1 month). Croplands and evergreen needleleaf forests demonstrate U-shaped dual memory patterns. Building on these temporal patterns, we identified biome-specific environmental drivers operating within each memory framework: wetlands primarily controlled by soil moisture, evergreen needleleaf forests by radiation, and closed shrublands by vapor pressure deficit. Beyond individual drivers, we uncovered critical nonlinear interactions that diverged from linear correlations at most sites (55 of 71 with ρ < 0.5). For instance, the carbon sink capacity of deciduous broadleaf forests depends on synchronized canopy development and photosynthetic activity, while closed shrublands show strong suppression of carbon uptake by atmospheric water deficit regardless of vegetation greenness, revealing how multiple drivers jointly regulate ecosystem functioning. Validating memory's fundamental role, ablation experiments confirmed that removing memory mechanisms degraded model prediction performance and altered environmental driver identification (Kendall's Tau < 0.5), demonstrating that temporal memory is integral to accurately modeling ecosystem carbon flux responses to environmental drivers. These findings provide mechanistic insights into temporal controls of carbon exchange across different biomes. This knowledge is critical for improving terrestrial carbon-climate feedback representations under global change.

The symbioses between corals and microorganisms, including the endosymbiotic dinoflagellates (family Symbiodiniaceae) and bacteria, are central to coral health and functioning. Certain species of Symbiodiniaceae in the genus Durusdinium are known to confer enhanced thermotolerance to corals and could therefore be beneficial under global climate change. However, association with thermotolerant algal symbionts may come with trade-offs that affect long-term coral persistence, and this study reports on one potentially consequential trade-off. We exposed colonies of the coral Galaxea fascicularis hosting Symbiodiniaceae in the genus Cladocopium (C-corals) or Durusdinium (D-corals) to elevated temperature equivalent to ~9.5 degree heating weeks. While C-corals were heat-sensitive, as evidenced by reduced Symbiodiniaceae cell density, photochemical efficiency and tissue pigmentation, they were resilient to tissue loss, maintained a stable bacterial community under elevated temperature, and showed limited mortality (12.5%) at the end of the 15-week recovery. Conversely, D-corals showed limited Symbiodiniaceae photodamage or tissue pigmentation loss under elevated temperature and initially demonstrated heat resilience. However, D-corals exhibited tissue loss and a significant reduction in newly formed polyps under elevated temperature, which occurred in parallel with a shift in their bacterial community composition toward taxa linked to bleaching, disease or algal overgrowth (e.g., Sphingomonas). Most D-corals died at the end of the recovery period. The intracellular bacterial communities in Cladocopium and Durusdinium freshly isolated from the experimental corals revealed symbiont-specific patterns, where Durusdinium showed strong affiliation with the diazotroph Ruegeria sp. Our findings show that G. fascicularis associating with the thermally tolerant Durusdinium may have higher susceptibility to tissue loss relative to corals with Cladocopium symbionts. If this trade-off occurs across corals that can associate with both Cladocopium and Durusdinium, it can have profound implications for reef persistence under global climate change, and further study is critical to inform conservation strategies aiming to build resilient reefs.

Forest conversion for agriculture is a major cause of tropical biodiversity loss, but its impacts vary with spatial scale. Higher species turnover in forests than in farmland means that land-use change causes greater biodiversity loss at broader than at local scales, yet broad-scale assessments are scarce. Phylogenetic diversity is increasingly prioritised in conservation to protect evolutionary history under global change, yet how deforestation-driven changes in phylogenetic diversity scale spatially and accumulate in regions of high species turnover remains unclear. We compiled a large field database from across 13 biogeographically diverse regions affected by deforestation for cattle farming, covering most of Colombia, a megadiverse tropical country. Using occupancy models, we estimated bird communities for 1547 (936 observed plus 611 never-observed) species across ecoregions and nationally in both forest and pasture habitats to quantify changes in phylogenetic diversity metrics and determine whether these impacts are dependent on spatial scale. We found an average loss of 2300 Myr of phylogenetic diversity at the country scale, with most species negatively affected across the phylogeny. Although single regional-scale relative loss was on average comparable to broader scales, there was high variability between regional units. The latter was especially critical when evaluating metrics of evolutionary distinctiveness, which are key indicators for biodiversity conservation planning. Such underestimation of national-scale impacts highlights the importance of sampling across multiple regions. Immediate conservation action is needed to safeguard evolutionarily unique species and prevent phylogenetic homogenisation driven by agricultural expansion across spatial scales-a threat often underestimated due to assessments limited to single biogeographic regions.

von Fromm S.F., Olson C.I., Monroe M.D., Sierra C.A., Driscoll C.T., Groffman P.M., Johnson C.E., Raymond P.A., Pries C.H. 2025 “Temporal and Spatial Dynamics of Soil Carbon Cycling and Its Response to Environmental Change in a Northern Hardwood Forest.” Global Change Biology 31: e70250. https://doi.org/10.1111/gcb.70250.

In the published version of this article, an error occurred during figure assembly. Specifically, panels b and d of Figure 5 are identical. Panel b is correct (observed vs. predicted SOC for the one-pool Oi/Oe model), whereas panel d should display the corresponding plot for the two-pool Oi/Oe model. The figure caption remains unchanged. No analyses, numerical results, statistics, or interpretations in the text are affected by this correction. All other figures, tables, and statements in the manuscript remain valid.

Figure 5 (corrected). Model results for the Oi/Oe layer using Dataset 2 (1998–2023). Panels (a) and (c) show measured mean SOC stocks (green circles) with standard deviation (black error bars) over time and modeled mean values (green line) with 95% credible intervals (green shaded area) for the models with one- and two-pool for the Oi/Oe layer, respectively. The dashed black line and gray shaded area represent the fitted linear regression and standard error for the observed SOC stocks. Panels (b) and (d) show observed versus predicted soil organic carbon (SOC) stocks (g C m⁻²) for the one- and two-pool models of the Oi/Oe layer, respectively.

High-latitude soils are warming rapidly due to climate change, raising concerns about long-term impacts on nitrogen (N) and carbon (C) cycling. Here, we investigate how decadal soil warming affects microbial N transformations in subarctic grasslands using natural geothermal gradients with soil temperatures ranging from ambient to +12.3°C. Seasonal measurements of N-pools and gross N transformation rates—including the production and uptake of amino acids, ammonium, and nitrate—were used to characterize microbial responses across warming intensities and time. Warming enhanced microbial turnover of amino acids by accelerating both gross amino acid production and uptake, while net depolymerization remained unchanged. In contrast, ammonium production remained stable, but its microbial uptake increased significantly with temperature. These decoupled responses suggest a microbial shift toward preferential use of organic N sources under warming, likely driven by reduced soil C availability. This strategy provides a dual source of C and N, enabling microbes to sustain high metabolic activity while limiting additional N losses. Supporting this, total soil N stocks declined early in the warming period—by 0.11 tons of nitrogen per hectare per degree Celsius over 5 years—but remained stable thereafter, indicating a transition toward more conservative microbial N cycling. Together, these findings reveal that long-term warming restructures microbial N use strategies, favoring tight organic N recycling and mineral N conservation. These physiological adjustments may buffer N losses under future warming and should be integrated into models predicting high-latitude ecosystem responses to climate change.

This review examines the multifaceted implications of global climate change on mammalian hibernators, emphasizing physiological, ecological and phenological impacts. While high-latitude habitats are experiencing faster overall warming, tropical and southern hemisphere regions face more unpredictable and variable climate alterations. Increasing temperature can directly affect hibernators by elevating hibernacula temperatures, shortening torpor bouts, increasing arousal frequency, and depleting energy reserves crucial for survival and reproductive success. Conversely, cold anomalies due to climate change may cause disruptive late-season cold snaps, affecting post-hibernation recovery and reproduction. The phenological timing of hibernation, emergence and reproduction is becoming increasingly decoupled from environmental cues, creating potential mismatches that threaten fitness and survival. Habitat modifications, including urbanisation, further modify microclimates, introducing new risks and opportunities influencing hibernation behaviour, resource availability and susceptibility to disturbances and diseases. Despite anticipated physiological resilience owing to broad thermal tolerances, many hibernating species already inhabit extreme environments and operate near their physiological limits, thus are even more at risk through ecological disruptions as climate variability intensifies. Ultimately, the capacity for adaptive phenotypic plasticity combined with ecological resilience will determine species' future persistence, with high-latitude species potentially more vulnerable to ecological disruptions like habitat loss, predation and disrupted food webs, while tropical species face greater physiological risk.

RETRACTION: A.J. Smith, G.L. Noyce, J.P. Megonigal, G.R. Guntenspergen, M.L. Kirwan, “ Temperature Optimum for Marsh Resilience and Carbon Accumulation Revealed in a Whole-Ecosystem Warming Experiment,” Global Change Biology 28, no. 10 (2022): 3236–3245, https://doi.org/10.1111/gcb.16149.

The above article, published online on 03 March 2022 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the authors; journal Editor-in-Chief, Danielle Way; and John Wiley & Sons, Ltd. The authors noticed an error in the analysis resulting in substantial alterations to the findings and conclusions. An erroneous “-1” was applied to all data, meaning that the maximum found was actually a minimum. This error was carried through the entire paper and affects not just the central finding, but the entire argument in the paper. Therefore, the paper has been retracted.