The temperature sensitivity (Q10) of soil carbon (C) release is a key parameter for evaluating soil C stability under climate warming, with particular importance in high-latitude regions that are highly vulnerable to rising temperatures. Nevertheless, the mechanisms by which nitrogen (N) addition modulates the temperature sensitivity of soil C release remain insufficiently understood. Here, we collected soils from a long-term N addition experiment in a high-latitude boreal forest and conducted controlled incubations to assess how N addition influences soil CO2 release and its temperature sensitivity. We found that N addition significantly suppressed soil CO2 release across all incubation temperatures (5°C, 15°C, and 25°C), yet its effects on Q10 were nonlinear. Specifically, N addition enhanced Q10 between 5°C and 15°C but suppressed Q10 between 15°C and 25°C. Both CO2 release and Q10 were strongly associated with bacterial and fungal diversity and biomass, as well as with the activities of key C- and N-cycling enzymes (e.g., β-glucosidase, cellobiohydrolase, and N-acetyl-glucosaminidase). However, the effects of N addition on CO2 release and Q10 were primarily mediated through both direct and indirect influences on microbial properties. Together, these findings demonstrate that N addition regulates soil CO2 release and Q10 mainly through microbial pathways, underscoring the pivotal role of microbial processes in determining high-latitude carbon dynamics and their feedbacks to climate change.
Tropical montane cloud forests (TMCFs) are globally important ecosystems, acting as large carbon sinks and supporting exceptional biodiversity. However, climate-driven declines in rainfall threaten these forests, but their responses to long-term soil moisture deficit remain poorly understood. We implemented a 5-year throughfall exclusion (TFE) experiment in a Peruvian TMCF, reducing soil moisture by 69.1% across a 0.09 ha plot. We compared the full carbon cycle budget, and surveyed tree physiological traits linked to hydraulics, metabolism and nutrients in the TFE plot and an adjacent, unmodified control (CON) plot. Soil drought reduced gross primary productivity by 4.24 ± 1.97 Mg C ha−1 year−1 but did not change net primary productivity because of an equivalent 3.38 ± 1.42 Mg C ha−1 year−1 decline in autotrophic respiration. Net ecosystem exchange also remained unchanged over 5 years of soil drought. Trees did not change xylem conductivity, hydraulic safety margins or photosynthetic capacity in the TFE, but did have 0.027 ± 0.011 g cm−3 denser wood and 4.58% ± 1.03% higher trunk starch concentrations. These results suggest that trees in TMCF avoid hydraulic failure and carbon starvation under sustained soil moisture drought via metabolic downregulation, resource conservation and non-structural carbohydrate storage. However, reduced uptake of nutrients (nitrogen, phosphorus, calcium) and 90.6% ± 29.8% decline in fruit production may impact future growth and demography. Our findings demonstrate surprising resilience of TMCFs to sustained, severe soil drought but highlight potential impacts on nutrient cycling and reproduction under climate change. Understanding the impacts of soil drought in conjunction with other climatic changes (e.g., fog reduction, temperature increases) is needed to fully assess the resilience of TMCFs to climate change.
Warming winter temperatures are driving range expansion of tropical, cold-sensitive mangroves into temperate ecosystems. Along the Atlantic coast of North America, the mangrove range limit is particularly sensitive to climate variability and historical data demonstrate that the mangrove-salt marsh ecotone on this coast has shifted recurrently during recent centuries. However, a comprehensive understanding of how this mangrove-salt marsh ecotone may shift in the future remains lacking. Here, we combine ensemble forecasting of mangrove distribution for the next century with high-resolution oceanographic dispersal simulations, phenological observations, and historical hurricane data to project future mangrove-salt marsh dynamics at the rapidly changing range limit in northeastern Florida (USA). We show that warming winter temperatures will drive continued poleward expansion of mangroves along North America's Atlantic coast, potentially reaching South Carolina by 2100. With ongoing climate change, suitable mangrove habitat is projected to expand beyond the current range limit, and dispersal simulations suggest successful colonization of these sites from established mangrove populations. Additionally, patterns in hurricane directionality and intensity and field reports of propagule presence reveal that these high-energy events may significantly contribute to future mangrove range expansion by facilitating long-distance, storm-driven propagule dispersal. The encroachment of mangroves in salt marsh-dominated latitudes is expected to substantially modify wetland ecosystem function and structure, emphasizing how the identification of newly colonizable habitat can inform conservation strategies and site-specific decisions on mangrove management.
Climate change is increasing drought frequency, threatening the stability of soil carbon sinks. While droughts are known to accelerate soil organic matter decomposition and enhance CO2 emissions, the long-term effects of recurrent droughts on soil remain unclear. We addressed this pressing issue by modelling long-term drought events in a temperate heathland on organo-mineral soil using the ECOSSE biogeochemical model and developing new metrics to assess changes in soil organic carbon (SOC) sequestration and stabilisation. Across all scenarios, drought events decreased the size of microbial (BIO) and humified (HUM) SOC pools by up to 15% and 8% respectively. Short-interval droughts weakened the BIO-to-HUM transfer, leading to incomplete recovery after rewetting, whereas prolonged droughts increased decomposition of stable pools at depth but allowed only partial re-equilibration during recovery. These changes were mirrored by contrasting responses in the carbon use efficiencies of labile (CUEI) and stable (CUES) pools. During frequent droughts, CUEI remained relatively stable, while the contribution of CUES increased indicating a higher contribution of stable SOC pools under soil moisture stress. The carbon sequestration efficiency (CSE = CUEI/CUES) declined by up to 15% under prolonged droughts compared with more frequent drought-rewetting cycles, signalling a progressive reduction in soil carbon sequestration. The stabilisation efficiency (SE = ΔHUM/ΔBIO) declined to about 40%, implying that recurrent droughts reduced the efficiency with which microbial carbon was stabilized into the HUM pool. Collectively, these metrics revealed a reversal in the CSE-water relationship: CSE increased with soil water during drought but declined after rewetting, indicating a persistent post-drought decoupling between decomposition and stabilisation processes. Recurrent droughts thus reshape SOC dynamics reducing CSE and altering the balance between decomposition and stabilisation with depth. Drought frequency rather than duration, emerges as the dominant control on long-term soil carbon stability in organo-mineral systems.
The natural process of silicate weathering has inspired two CO2 removal technologies: enhanced weathering and mineral carbonation. Here, in a 15-month mesocosm experiment, both approaches were combined, with the aim of maximising CO2 removal. To do so, pre-carbonated steel slags (basic oxygen furnace (BOF) and argon oxygen decarburisation (AOD) slag) with mineral carbonation rates ranging from 0.04 to 0.13 t CO2/t rock were applied to soil planted with maize. Other treatments included uncarbonated slags and basalt for comparison. Aside from the commonly assessed leachate and soil solid carbonate pool, which contribute to inorganic CO2 removal, also other soil pools (plant, exchangeable, (hydr)oxide, SOM) not directly linked to CO2 removal were assessed. These alternative sinks are key to better understand the low inorganic CO2 removal efficiencies reported in many experiments. Indeed, also in this experiment, the realised inorganic CO2 removal of enhanced weathering remained low in all treatments (< 0.014 t CO2/t rock), except for the highest carbonated slag treatment, which removed slightly more CO2 (0.04 t CO2/t rock). Thus, with a high degree of prior mineral carbonation, the inorganic CO2 removal during enhanced weathering was increased. This was the case even though carbonated slags weathered slower. These results demonstrate that active weathering does not necessarily imply high inorganic CO2 removal. While slags weathered almost entirely after only 4 months, less than 5.3% of the theoretical possible CO2 removal was realised. If weathering occurred too rapidly, the formation of secondary minerals such as (hydr)oxides and/or aluminosilicate clays likely immobilised base cations, thereby constraining inorganic CO2 removal. For uncarbonated slags, ~58% (BOF) and 70% (AOD) of the added base cations were likely locked in (hydr)oxides/aluminosilicate clays. These findings underline that understanding the fate of weathering products (beyond the leachate and carbonate pool) is key to assess the ‘true’ inorganic CO2 removal potential of enhanced weathering.
Ecological traps, poor-quality habitats that attract animals, significantly threaten ecosystems but have rarely been documented in marine environments. In fish, early life-history events, such as larval settlement, play a key role in shaping individual survival, population stability, and community interactions. While evidence suggests that late-stage fish and invertebrate larvae exhibit a phototactic response, the effects of light pollution on larval settlement and survival remain poorly understood. Here, we simulated environmental light pollution on coral reefs using artificial light to examine its impact on fish settlement and post-settlement consequences. We found that settlement was up to eight times higher onto corals exposed to light pollution compared to those under natural conditions. However, exposure to light pollution reduced recruit survival by half, desynchronized settlement from the full moon and reduced size at settlement. We identified key mechanisms contributing to increased mortality of individuals exposed to artificial light, including disruptions in resting metabolic rhythm and higher predation (due to heightened predator attraction). Additionally, we reveal potential trait compensation in body condition and maximum metabolic rate, traits linked to fitness. However, despite these potential compensatory mechanisms, light pollution functions as a severe ecological trap for fish, attracting individuals into suboptimal environments where they experience higher mortality. This underscores the need to regulate light pollution as a critical environmental stressor.
Brazil is globally known as a megadiverse country that holds within its six biomes a high level of biodiversity and a large number of endemic species, often with important and distinct roles for the provision of ecosystem services and global climate regulation. Whilst the natural beauty, abundant life and natural resources of the country have inspired the national anthem, encompassing the term ‘splendid cradle’, Brazil is being adversely affected by biological invasions, particularly by invasive plants. Historically, Brazilian research on alien plant species has focused on management interventions and population-derived aspects, such as the negative effects on native communities associated with plant invaders and removal protocols. In contrast, assessments on the contribution of invasive plants to climate modifications, through their impacts on greenhouse gas (GHG) emissions and soil carbon stocks, have been overlooked and remain largely unstudied. According to our estimates, up to 150,424,000 Mg CO2-eq year−1 or ca. 7% of the country's national inventory might be emitted by invasions associated with the top 10 most problematic plants, with an annual loss of nearly US$ 2 billion in carbon credits. Here, we analyse the potential impact that invasive plants have on climate change based on the most problematic invasive plants in Brazil, and recommend a list of actions, including, but not limited to: (i) accurate mapping of the extent of plant invasions; (ii) dedicated studies on soil GHG emissions in invaded areas; (iii) quantification of plant-mediated emissions and their contribution to ecosystem budgets; (iv) more detailed research on soil carbon stocks and pools and how plant invaders might affect them; and (v) assessments of the most appropriate restoration protocols that would minimise any climate-related impacts. With this information, Brazil can become closer to the ‘splendid cradle’ ideal and lead the development of more accurate national GHG inventory reporting.
Desert ecosystems, which cover more than one-third of Earth's land surface, are experiencing intensifying pressures from land-use disturbances and climate change that threaten their stability and biodiversity. Yet despite their global extent and ecological importance, deserts remain among the least studied biomes, particularly with respect to the belowground processes that sustain productivity, biogeochemical cycling, and long-term ecosystem resilience. Most prior work has focused on vegetation, leaving the roles of soil microbiomes and plant functional trait coordination comparatively underexplored. This knowledge gap is significant because growing evidence shows that microbial dynamics and plant trait syndromes jointly regulate nutrient cycling, carbon stabilization, and drought recovery, potentially determining whether desert ecosystems cross critical thresholds under future climate scenarios. This review synthesizes recent advances in understanding the influence of microbial legacies (persistent effects of past environmental conditions) on ecosystem processes, and how desert plants adapt via coordinated traits that optimize water and nutrient use under extreme conditions. We propose a novel framework that integrates belowground microbial responses and aboveground plant trait strategies, highlighting their interactions and feedback loops in shaping desert ecosystem resilience. By explicitly linking these two domains, the review addresses a major knowledge gap in predicting dryland responses to intensifying climate extremes, offering a mechanistic foundation for improving ecological models and management strategies. This integrated perspective provides new insights into the mechanisms that underlie adaptation to climate stress and offers actionable pathways for conservation, restoration, and climate adaptation in desert landscapes. By bridging microbial ecology and trait-based plant science, this review contributes to a more comprehensive understanding of how desert ecosystems can persist and function in a rapidly changing world.
Barriers represent one of the greatest threats to river integrity and freshwater fish, as they fragment habitats and impair species dispersal, particularly in a scenario of climate change. In this context, we applied a novel framework that combined predictions of species distribution models with a river connectivity index to identify accessible and climatic-environmental suitable habitats for frugivorous and socioeconomically important fish in the Amazon basin. We also ranked dams based on their potential for river fragmentation and blocking access to climate refuge for fish species that provide essential ecosystem functions and services in the Amazon. Our results revealed that there are still extensive areas that remain both connected and climatic-environmentally suitable along the Amazon-Solimões rivers, acting as core areas for fish dispersal and tracking suitable habitats. However, the planned expansion of hydropower infrastructure combined with climate change can lead to a contraction of areas that will remain simultaneously climatic-environmental suitable and connected. By identifying and ranking the most impactful barriers, our results can provide innovative and applicable information for sustainable energy planning decisions in the Amazon. These results can inform policies and conservation actions aimed at preserving river connectivity, biodiversity, and ecosystem services under rapidly changing conditions.
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