Climate extremes: observations, modeling, and impacts

A meta-analysis of the regional extreme rainfall events in the Indian sub-continent during the southwest monsoon period

The present review focuses on extreme rainfall events (EREs) over the Indian subcontinent during the southwest monsoon period. The evolution of ERE studies across India concentrates mainly on the regional characteristics that have influenced these events during the past decade. It evolved slowly by accounting for different indices to represent extremes, understanding causative mechanisms, and improving their forecasting. There are many methods for estimating EREs, each suited to various objectives. Rather than seeking a perfect method, the studies may adopt methodologies based on the purpose and scope. Moreover, EREs impose severe socioeconomic impacts on India, with heavy burdens on communities and resources. Factors such as low-pressure systems, Indian Ocean warming, and circulation shifts contribute to these extremes. Northwest India has seen a significant rise in ERE frequency and intensity in recent decades due to enhanced convective instability and moisture transport by various climate drivers. In contrast, Northeast India shows a decline in EREs driven by synoptic systems. EREs in the Himalayas are more complex and influenced by tropical and extratropical drivers. Regions like Kerala and the northeastern states face frequent ERE-linked flooding, while the Western Ghats show a declining trend. The ERE in the different regions show different dynamics due to their heating structure, moisture availability, and atmospheric instability factors. Thus, regional ERE forecasting is complex, but combining numerical models with machine learning can enhance accuracy and reliability. Future projections indicate a significant increase in regional EREs, but uncertainties persist due to models' biases. The findings underscore the need for improved modeling strategies and targeted policy measures to mitigate the adverse impacts of future EREs. This review offers insights into India's current state and research prospects, highlighting critical areas for further investigation and enhanced forecasting.

A Self-Cleaning Janus Textile for Highly Efficient Heating and Cooling Management

Textiles capable of achieving both solar heating and radiative cooling play a pivotal role in outdoor thermal management. Despite significant advancements, further improvements are necessary to enhance the optical performance and versatility. In this study, we developed a Janus textile comprising a porous poly(vinylidene fluoride-co-hexafluoropropylene) [P(VdF-HFP)HP] cooling layer (96.4% solar reflectance and 95.3% mid-infrared emissivity) and a Cu-nanoparticle-based heating layer (95.5% solar absorption and 89.1% mid-infrared reflectance). After 30 washing cycles, its performance remains stable. Field tests demonstrate impressive temperature differentials of +41.1 °C for heating and -4.5 °C for cooling relative to ambient conditions, thereby extending the thermal regulation range by 26.6 °C compared to conventional cotton textiles. Additionally, nanostructured surfaces impart hydrophobicity, oleophobicity, and fouling resistance. This design offers a sustainable solution with superior thermal management, stability, and self-cleaning ability for outdoor protection.

Adapting to an increasingly stressful environment: Experimental evidence for 'micro-evolutionary priming'

In many natural systems, animal populations are exposed to increasing levels of stress. Stress levels tend to fluctuate, and long-term increases in average stress levels are often accompanied by greater amplitudes of such fluctuations. Micro-evolutionary adaptation may allow populations to cope with gradually increasing stress levels but may not prevent their extirpation during acute stress events unless adaptation to low stress levels also increases their tolerance to acute stress. We tested this idea, here called 'micro-evolutionary priming', by exposing populations of the monogonont rotifer species Brachionus calyciflorus to four levels of copper stress (control, low, intermediate and high) during a multigenerational selection experiment. Subsequently, in a common garden experiment, we exposed randomly selected subsets of genotypes (clones) of each of these populations to low, intermediate and high copper levels and assessed their population growth performance across multiple generations. Compared to populations with an exposure history to copper, genotypes of control populations suffered strong growth reductions when exposed to intermediate and high levels of copper, mainly as a result of high mortality rates. Remarkably, when exposed to low copper levels, fitness differences between genotypes of control populations and populations adapted to these low levels were very small, whereas the latter strongly outperformed the former at intermediate and high copper levels. These results highlight the potentially strong but hitherto largely ignored impact of micro-evolutionary priming on the performance of populations in a changing environment. We discuss the potential consequences of micro-evolutionary priming for the persistence of populations and the spatial eco-evolutionary dynamics of metapopulations.

The structural and key technological analysis of phase-change cooling garments

The frequent occurrence of extreme high-temperature climates poses severe threats to human health and safety. Personal cooling garments, as an effective means to alleviate heat stress among outdoor workers, have garnered significant attention domestically and internationally. Phase-change cooling garments (PCCGs) have gained popularity due to their cost-effectiveness, portability, environmental benefits and energy efficiency. However, PCCGs face limitations, e.g., short cooling duration, low thermal conductivity of phase-change materials (PCMs) and challenges in regulating phase transition temperature. This study reviews the evolution of cooling garments, examines the design and implementation of PCCGs, and discusses key technologies in their development. Future research is needed to explore novel PCMs, heat transfer models, garment design and intelligent temperature control. The goal is to create standardized, portable and comfortable PCCGs. Furthermore, commercial applications of PCCGs are expanding, highlighting their growing importance in improving occupational safety and ergonomics in high-temperature environments.

Effects of Climate and Land Use on the Population Dynamics of the Bank Vole (Clethrionomys glareolus) in the Southernmost Part of Its Range

This study investigated the effects of habitat structure and climatic variables on populations of bank voles (Clethrionomys glareolus), a northern species with adaptations to cooler climate, at the southern end of their range in Western Europe over a 16-year period. This is the first long-term analysis of its kind in this region. The study aims to understand how these variables influence the population dynamics and occupancy of bank voles. The results suggested that warmer years and extreme precipitation events lead to a reduction in bank vole abundance. Although changes in land use were minimal in the plots studied, changes in forest composition, particularly the expansion of coniferous forests at the expense of deciduous forests, were also related to lower bank vole abundance. Occupancy models, taking into account detectability, indicated stable occupancy in all regions. Our results suggest that climate change and habitat alterations, such as changes in forest composition, could pose threats to bank vole populations in these regions.

Dynamic evaluation of winter wheat's freezing resistance under different low-temperature periods and durations

Winter extreme low temperature events have been occurring frequently both before and after the winter season. The freezing resistance temperature of wheat is far lower than the intensity of low temperatures during the mid-winter period. Therefore, it is necessary to further quantify and evaluate the impact of low-temperature periods and durations during the early winter and the green-up period on the freezing resistance of wheat, based on different evaluation indicators. Through conducting experiments in an artificial low-temperature control chamber, this study investigates the critical temperature thresholds for the impact of different low-temperature periods and durations on the tiller and yield of winter wheat, as well as the critical temperature thresholds for soil effective negative accumulated temperature. The results demonstrate that (1) the tiller mortality rate (RT) and yield reduction rate (RY) of winter wheat during the winter increase with the severity and duration of low temperatures, showing an S-shaped curve. The winter wheat mortality rate during the early winter is related to the soil effective negative accumulated temperature in an exponential function, while the mid-winter and green-up stages have a linear relationship. (2) The freezing threshold temperatures for the RT, RY and soil negative accumulated temperature (SENAT) in different low-temperature periods (early winter, mid-winter, and green-up periods) range from - 11.7 to -17.9 °C, -9.4 to -15.6 °C, and 15.9 to 131.7 °C·h (2.2 to 16.8 °C·d), respectively. (3) The freezing threshold temperatures for the RT and RY in different low-temperature durations (1 day, 2 days, and 3 days) range from - 2.8 to -17.9 °C and - 9.4 to -15.6 °C, respectively. The findings of this study provide technical support and scientific guidance for the global cultivation structure and variety layout of winter wheat under the background of climate warming, as well as for the prevention and reduction of freezing damage and yield losses.

Enhancing wheat resilience: biotechnological advances in combating heat stress and environmental challenges

Climate change, with its increasing temperatures, is significantly disrupting global agricultural systems, and wheat, a key cereal crop faces severe challenges. Heat stress has emerged as a critical threat, accelerating wheat growth, leading to premature maturation, reduced grain filling, and ultimately lower yields. The situation is exacerbated by more frequent and intense heat waves, particularly in regions already struggling with water scarcity. Maintaining the delicate balance of temperature and water necessary for optimal wheat production is becoming challenging, posing a serious risk to global food security. Therefore, there is an urgent need to develop adaptive strategies with innovations in breeding and transgenic technologies crucial to improving wheat resilience to environmental stresses, especially to combat the growing impacts of heat stress. Modern tools like CRISPR/Cas9, Transcription Activator-Like Effector Nucleases, and Zinc Finger Nucleases have been instrumental in developing wheat varieties with improved traits. However, the future of wheat cultivation requires more than just resistance to a single stressor. As climate change intensifies, there is an urgent need for wheat varieties that can withstand multiple stresses, including heat, drought, and pests. Developing these multi-stress-tolerant cultivars is crucial for ensuring food security in a rapidly changing climate.

Thermophysiology and Cognitive Performance of Live-Line Workers in High-Temperature and High-Humidity Environments

Live-line workers' physiological and psychological conditions are significantly affected when operating in high-temperature and high-humidity environments, influencing both work efficiency and safety. Fifteen participants, wearing high-voltage-shielding clothing, were tested in a simulated environmental chamber at temperatures of 23 °C, 32 °C, and 38 °C, and relative humidities of RH 30%, RH 50%, and RH 75%. The experiment involved walking at a speed of 5 km/h for 75 min., during which the participants' skin temperature, core temperature, thermal sensation, heart rate, blood oxygen level, sweat rate, and cognitive performance were measured. The results indicated a marked increase in both core and skin temperatures with rising temperature and humidity levels. At 38 °C/RH 75%, the core temperature reached 38.39 °C, and the average skin temperature was 36.8 °C. Significant differences in skin temperature were observed across different body regions (p < 0.05), with this disparity decreasing as the temperature increased. Heart rate, blood oxygen level, and sweat rate also exhibited significant differences across varying conditions (p < 0.05). Specifically, heart rate and blood oxygen level increased with higher temperature and humidity, while blood oxygen levels decreased as the environmental temperature and humidity increased. In addition, as temperature and humidity levels rose, the participants' error rate and average response time in cognitive tasks increased. The negative impact of temperature and humidity on performance efficiency and accuracy was more pronounced in complex cognitive tasks. The study further found that thermal sensation voting (TSV) remained within the range of -0.5 to +0.5, with the average skin temperature in the thermal comfort zone ranging between 33.4 °C and 34.1 °C. It is recommended that the environmental temperature in high-humidity conditions be maintained between 20.8 °C and 25.8 °C. Our findings provide a theoretical foundation for the development of personal protective equipment for live-line workers.

Narrow Margins: Aerobic Performance and Temperature Tolerance of Coral Reef Fishes Facing Extreme Thermal Variability

Climate change is driving rising average sea temperatures and the intensification of thermal variability. Tropical coral reef fishes have evolved under thermally stable conditions to function optimally within a narrow temperature range, with many currently living close to their upper thermal limits. However, recent work has demonstrated that some species possess additional capacity, such as reductions in basal metabolic rates (i.e., 'plastic floors'), to compensate for the acute effects of thermal challenges when assessed over multigenerational timeframes. In this study, we use the 'plastic floors and concrete ceilings' hypothesis to generate and then test predictions regarding the thermal physiology of reef fishes in the world's hottest and most thermally variable coral reef ecosystem (southern Arabian/Persian Gulf). By comparing three species of reef fishes (Scolopsis ghanam, Ecsenius pulcher and Cheilodipterus novemstriatus) from the southern Arabian/Persian Gulf, with an annual temperature range of 18.0°C-36.5°C, to conspecifics from nearby but more thermally benign (~21.0°C-32.0°C) reefs in the Gulf of Oman, we find enhanced upper thermal limits and a broadening of the temperature performance curves for aerobic scope in the Arabian/Persian Gulf, but no evidence for changes in basal metabolic rates ('plastic floors'). Despite these conserved increases in temperature tolerance, the summer thermal safety margins of Arabian/Persian Gulf fishes were 1.47°C lower than those of conspecifics from the Gulf of Oman, demonstrating that while the temperature tolerance of tropical coral reef fishes is somewhat plastic over multigenerational timeframes, its rate of change is likely insufficient to keep pace with the rising average temperatures and growing thermal variability expected under climate change.

Contrasting drought sensitivity of Eurasian and North American grasslands

Extreme droughts generally decrease productivity in grassland ecosystems1-3 with negative consequences for nature's contribution to people4-7. The extent to which this negative effect varies among grassland types and over time in response to multi-year extreme drought remains unclear. Here, using a coordinated distributed experiment that simulated four years of growing-season drought (around 66% rainfall reduction), we compared drought sensitivity within and among six representative grasslands spanning broad precipitation gradients in each of Eurasia and North America-two of the Northern Hemisphere's largest grass-dominated regions. Aboveground plant production declined substantially with drought in the Eurasian grasslands and the effects accumulated over time, while the declines were less severe and more muted over time in the North American grasslands. Drought effects on species richness shifted from positive to negative in Eurasia, but from negative to positive in North America over time. The differing responses of plant production in these grasslands were accompanied by less common (subordinate) plant species declining in Eurasian grasslands but increasing in North American grasslands. Our findings demonstrate the high production sensitivity of Eurasian compared with North American grasslands to extreme drought (43.6% versus 25.2% reduction), and the key role of subordinate species in determining impacts of extreme drought on grassland productivity.

Quantifying disturbance effects on ecosystem services in a changing climate

Disturbances, such as hurricanes, fires, droughts and pest outbreaks, can cause major changes in ecosystem conditions that threaten Nature's contributions to people (ecosystem services). Climate change is intensifying disturbances, posing risks to ecosystem services. To assess those risks, we develop a flexible, functional trait-based approach to quantify ecological, ecosystem service and economic impacts from disturbance regimes. Our broadly applicable approach integrates knowledge from disturbance ecology and ecosystem service valuation, and we highlight the pitfalls of using either perspective in isolation. We demonstrate our approach by quantifying impacts to timber and recreational enjoyment from extreme windstorms in a midlatitude forest. While we predict large potential losses to these services under historical and future disturbance regimes, common ecological metrics of compositional and biomass stability are inadequate for predicting these impacts. We then provide a roadmap for applying our approach across different social-ecological systems, illustrating the approach for crop pollination, flood hazard mitigation and cultural values from coral reefs-which all face intensifying disturbances. This study highlights and provides tools to address the pressing need to consider disturbances in future ecosystem service assessments.

Gain of thermal tolerance through acclimation is quicker than the loss by de-acclimation in the freeze-tolerant potworm, Enchytraeus albidus

Environmental temperature variation, naturally occurring or induced by climate change, leads organisms to evolve behavioural and physiological responses to handle thermal fluctuations. Among them, phenotypic plasticity is considered a fundamental response to natural thermal variations. Nevertheless, we know little about the rate of thermal acclimation responses and the physiological mechanisms underpinning phenotypic plasticity in freeze-tolerant invertebrates. We assessed the temporal dynamics of heat and cold tolerance plasticity in the freeze-tolerant potworm Enchytraeus albidus following thermal acclimation. Acclimation responses were investigated in worms cultured at 5 or 20°C and acclimated for varying duration (hours to weeks) at the same temperature or relocated to the opposite temperature. The rate of phenotypic responses of thermal tolerance was evaluated by assessing survival after exposure to high and low stressful temperatures. Worms cultured at 5°C were more cold tolerant and less heat tolerant than worms cultured at 20°C. The plasticity of thermal tolerance in E. albidus varied in scope and response time according to both culture and acclimation temperatures: acclimation at 20°C of worms cultured at 5°C increased heat survival within 1 day and reduced cold tolerance in 5 days, while acclimation at 5°C of worms cultured at 20°C did not affect heat survival but considerably and quickly, within 1 day, increased cold tolerance. Effects of acclimation were also assessed on membrane phospholipid fatty acid (PLFA) composition and glycogen content of worms, and showed that improved tolerance was linked to changes in membrane PLFA desaturation and chain length.

Cold tolerance and prediction of northern distribution of Histia rhodope (Lepidoptera: Zygaenidae) in China

Histia rhodope (Cramer) (Lepidoptera: Zygaenidae) is one of the most destructive defoliating pests of the landscape tree Bischofia polycarpa (Levl.) S in China and other Southeast Asian regions, posing a critical threat to urban landscapes and their ecological benefits. This pest has shown a trend of northward range shift in recent years in China, making it urgent to understand its potential distribution. This study investigated the cold tolerance of overwintering H. rhodope larvae from October 2022 to March 2023 and estimated their overwintering potential in China. The results showed that the supercooling points (SCP) differed significantly across months. The SCP tended to decrease as the ambient temperature dropped until January, after which it gradually increased until the end of winter. The highest monthly mean SCP was -7.5 ± 2.22°C (October 2022), while the lowest monthly mean SCP was -15.09 ± 2.61°C (January 2023). The mortality rate increased with longer exposure times and lower exposure temperatures but decreased as winter progressed. Moreover, 50% and 90% lethal temperature (Ltemp50 and Ltemp90) exhibited a similar trend, decreasing to a minimum in January 2023, which indicates increased cold tolerance during the colder months. Using Ltemp90 in January as the isotherm for its northern limit indicated that H. rhodope may be limited by low temperatures along the 40°N latitude. These results provide a basis for predicting the dispersal potential and possible geographic range of this pest in China.

Fast-Developing Dynamic Radiative Thermal Management: Full-Scale Fundamentals, Switching Methods, Applications, and Challenges

Rapid population growth in recent decades has intensified both the global energy crisis and the challenges posed by climate change, including global warming. Currently, the increased frequency of extreme weather events and large fluctuations in ambient temperature disrupt thermal comfort and negatively impact health, driving a growing dependence on cooling and heating energy sources. Consequently, efficient thermal management has become a central focus of energy research. Traditional thermal management systems consume substantial energy, further contributing to greenhouse gas emissions. In contrast, emergent radiant thermal management technologies that rely on renewable energy have been proposed as sustainable alternatives. However, achieving year-round thermal management without additional energy input remains a formidable challenge. Recently, dynamic radiative thermal management technologies have emerged as the most promising solution, offering the potential for energy-efficient adaptation across seasonal variations. This review systematically presents recent advancements in dynamic radiative thermal management, covering fundamental principles, switching mechanisms, primary materials, and application areas. Additionally, the key challenges hindering the broader adoption of dynamic radiative thermal management technologies are discussed. By highlighting their transformative potential, this review provides insights into the design and industrial scalability of these innovations, with the ultimate aim of promoting renewable energy integration in thermal management applications.

Rainfall distribution variability controls surface but not belowground litter decomposition in a semi-arid shrubland

Introduction

Rainfall patterns are expected to become increasingly erratic as a result of global climate change, with more intense but less frequent rainfall events leading to an increased occurrence of drought events. This process may lead to significant declines in vegetation cover and subsequent increases in soil erosion, consequently accelerating the bury of detached litter by soil deposition and the mixture of residues from different plant species. Responses of litter decomposition to increasing rainfall variability in distribution and subsequent litter mixing or soil cover have scarcely received attention.

Methods

To fill this gap in our knowledge, we analyzed the influence of rainfall variability, soil cover, and litter mixing on shrub-species litter decomposition in a semi-arid shrubland. We explored the effects of redistributing the frequency and amount of precipitation on surface and belowground decomposition of litter from two separate or mixed predominant shrubs.

Results

Decomposition of belowground litter was consistently higher than that of surface litter over the entire field-incubation process. Mass loss significantly decreased in surface litter but not in belowground litter due to the lower frequency and larger amount of precipitation compared to the control treatment. Furthermore, exclusion of 30% precipitation had no significant effects on decomposition of either surface or belowground litter. We observed stronger synergistic effect for belowground litter mixture relative to surface litter mixture of the two shrubs, especially in the hotter months over the 5-month incubation.

Discussion

These findings support that rainfall variability in terms of distribution pattern rather than in the amount controls the litter decomposition on the soil surface in the semi-arid shrubland. Meanwhile, soil burial or litter mixing have greater effects on litter decomposition, individually or jointly. Together, our results highlight the need to consider rainfall distribution variability and incorporate soil-covering and litter-mixing as driving factors of organic matter turnover in drylands.

Different impact of a severe storm on two gorgonian species

Extreme events influence ecosystem dynamics, but their effects on coastal marine habitats are often poorly perceived compared to their terrestrial counterparts. The detailed study of changes in benthic communities related to these phenomena is becoming urgent, due to the increasing intensity and frequency of hurricanes recorded in recent decades. Slow-growing benthic sessile organisms are particularly vulnerable to mechanical impacts, especially the large long-lived species with branched morphology that structure Mediterranean coralligenous assemblages. The present study evaluates the effects of the severe storm occurred in October 2018, and classified as one of most violent that ever struck north-western Mediterranean coasts, on two gorgonian species, the scleralcyonacean Corallium rubrum (with a solid carbonate axial skeleton) and the malacalcyonacean Paramuricea clavata (with a flexible proteinaceous axis). Comparing the cover and density of the two species before and after the severe storm, C. rubrum showed a decrease of more than 50% in one surveyed site. In contrast, P. clavata population did not show a decrease, and exhibited the highest density and cover in the same site, thanks to the high hydrodynamic condition which are favourable for this species. In this study, cover evaluation proved to be more time-efficient than counting colonies, and reduced the risk of errors. The present example highlighted the importance of continuous monitoring, including the assessment of the biological and ecological traits of the species, to provide a complete picture of their populations for conservation planning.

Are dispersal and dormancy alternative strategies for overcoming environmental variability?

Dispersal and dormancy serve as strategies for persistence in varying and uncertain environments and are critical to ecological models of biodiversity maintenance. Theories of specific ecological scenarios that favor dispersal, dormancy, or their covariance are rarely tested empirically, particularly in response to realistically complex patterns of spatiotemporal environmental variation. To resolve these complexities, we collected 20 populations of Vulpia microstachys, an annual grass native to California, from the field and grew them in a greenhouse, and on the offspring generation measured seed dispersal ability and seed dormancy rates. We hypothesized that seed dormancy rates, but not dispersal abilities, would be highest in populations from more productive, temporally variable sites, causing dispersal and dormancy to evolve independently-in other words, we leveraged evolved differences among populations to identify what ecological strategy (i.e., dispersal, dormancy, or both) is most likely to evolve at different parts of a variability gradient. Our data suggest that both dispersal and dormancy evolve to combat different axes and scales of spatial heterogeneity and can evolve independently (thus, they are not forced to covary). Most surprisingly, seed dormancy appears to have evolved as a strategy for overcoming microgeographic heterogeneity, an outcome that to our knowledge has not been considered by theory; we confirm the plausibility of this conclusion with a simulation. In sum, we provide much needed empirical data on the evolution of ecological strategies for coping with environmental variance, as well as a new perspective on the ecological function dormancy provides in heterogeneous landscapes.

From molecular to physiological responses: improved stress tolerance and longevity in Drosophila melanogaster under fluctuating thermal regimes

Climate change introduces greater thermal variability, profoundly affecting ectothermic species whose body temperatures rely heavily on the environment. Understanding the physiological and metabolic responses to such variability is crucial for predicting how these species will cope with changing climates. This study investigates how chronic thermal stress impacts mitochondrial metabolism and physiological parameters in Drosophila melanogaster, hypothesizing that a fluctuating thermal regime (FTR) activates protective mechanisms enhancing stress tolerance and longevity. To test this, Drosophila were exposed to constant 24°C or to an FTR of 24°C:15°C (day:night) cycle following an initial 5 day period at 24°C. The FTR group exhibited rapid transcript level changes after the first day of FTR, particularly those related to heat shock proteins, mitophagy and regulatory factors, which returned to initial levels after 5 days. Mitochondrial respiration rates initially decreased after 1 and 2 days of FTR, then recovered by day 5, indicating rapid acclimation. Enhanced antioxidant enzyme activities were observed early in the FTR group, after 1 day for mtSOD and SODcyt+ext and 3 days for both SOD and catalase, followed by a decline by day 5, suggesting efficient oxidative stress management. The FTR group showed lower CTmax on day 3, reflecting possible physiological strain at that time point, and complete recovery by day 5. Longevity increased under FTR, highlighting the activation of protective mechanisms with beneficial long-term effects. These results suggest that FTR prompts a temporal succession of rapid physiological adjustments at different levels of organisation, enhancing long-term survival in D. melanogaster.

Intraspecific Diversity in Thermal Performance Determines Phytoplankton Ecological Niche

Temperature has a primary influence on phytoplankton physiology and ecology. We grew 12 strains of Gephyrocapsa huxleyi isolated from different-temperature regions for ~45 generations (2 months) and characterised acclimated thermal response curves across a temperature range. Even with similar temperature optima and overlapping cell size, strain growth rates varied between 0.45 and 1 day-1. Thermal niche widths varied from 16.7°C to 24.8°C, suggesting that strains use distinct thermal response mechanisms. We investigated the implications of this thermal intraspecific diversity using an ocean ecosystem simulation resolving phytoplankton thermal phenotypes. Model analogues of thermal 'generalists' and 'specialists' resulted in a distinctive global biogeography of thermal niche widths with a nonlinear latitudinal pattern. We leveraged model output to predict ranges of the 12 lab-reared strains and demonstrated how this approach could broadly refine geographic range predictions. Our combination of observations and modelled biogeography highlights the capacity of diverse groups to survive temperature shifts.

Critical reproductive behaviors in Scaled Quail and Northern Bobwhite are affected by thermal variability and mean temperature

Animals can respond differently to shifting thermal variability versus thermal averages, both of which are changing due to climate warming. How these thermal variables affect parental care behaviors can reveal the ability of parents to modify their behaviors to meet the competing demands of their offspring's thermal needs and self-maintenance, which becomes critical in suboptimal thermal conditions. Further, the time frame used to examine the interplay between temperature and behavioral shifts (e.g., seasonal patterns in care vs. drivers of individual care decisions) can provide different information about the plasticity of parental care behavior. We investigated the relationship between thermal means, thermal variability, and incubation behaviors across multiple timescales in Scaled Quail and Northern Bobwhite. Both species decreased off-bout length during periods of high thermal variability, a novel finding among studies of avian parental behavior. Further relationships between thermal endpoints (mean vs. variation) and behavior differed depending on the temporal scale. For instance, total daily time spent off the nest was not influenced by daily average temperature, yet individual off-bout duration increased with increasing average temperature in the 2 h prior to the off-bout. These results provide evidence that thermal-behavioral relationships differ across scales and likely represent a bird's ability to modify their incubation strategy to rapidly respond to the immediate thermal environment (altering individual off-bout length based on temperature) to meet self-maintenance needs while resulting in a similar outcome for their nest (total daily off-bout time). However, longer off-bout durations during high temperature events can come with reproductive costs, sometimes resulting in acute offspring mortality when eggs or chicks experience lethal temperatures.

The environmental burden of inhalation

Inhalation systems, mostly metered dose inhalers (MDIs) and dry powder inhalers (DPIs), are currently submitted to a critical assessment for their carbon footprint (CF) and environmental impact. They are related to greenhouse gas (GHG) emissions and they produce waste of used devices with withheld drug residues and unused doses. However, with estimated contributions to anthropogenic GHG-emissions of 0.03 % for MDIs and 0.0012 % for DPIs globally, it may not be expected that mitigating the GHG emissions from inhalers will have a meaningful effect on the current climate change and global warming, notwithstanding that nationally these percentages may be somewhat higher, depending on the ratio of MDIs to DPIs and the total national CF. MDIs are particularly the preferred type of inhalers over DPIs in the USA and UK with ratios of 9: 1 and 7: 3 respectively. In such countries, a partial switch from MDIs to DPIs is to be recommended, providing that such a switch does not jeopardize the therapy. Using renewable energy only for the production and waste management of DPIs will make this type of inhaler almost climate neutral. A greater concern exists about inhaler waste, more particularly about the residual drug and unused doses in discarded devices. Inhalers contribute <0.02 % to global plastic waste annually and most plastic inhalers end in the domestic waste bin and not as litter polluting the environment with plastic. However, they do contain retained drug and unused doses, whereas even full inhalers are disposed. Because globally most municipal waste (70 %) ends up in dumps and landfills, leakage of the drugs into the soil and surface waters is a serious problem. It pollutes drinking water and endangers species and biodiversity. Therefore, a good collection system and an adequate waste management program for used inhalers seems to be the most meaningful measure to take for the environment, as this will stop inhalers and drugs from putting ecosystems at risk.

Responses of Body Mass, Organ Masses, and Metabolic Rates in Winter-Phenotype House Sparrows to Fluctuating Cold Temperatures

AbstractSmall birds in temperate regions are faced with a large range of environmental conditions throughout the year, including fluctuating temperatures. During cold winters, birds often exhibit an increase in metabolic rates, body mass, and pectoralis muscle mass because of the heightened energetic needs of thermoregulation. However, climate change is altering weather patterns, and in addition to widespread winter warming, temperature variability and the frequency of extreme temperatures are also expected to increase, including more winter cold snaps. In the present study, our goal was to determine whether an increase in temperature variability in a cold environment will impact the metabolic rates, organ masses, and body mass of winter-phenotype house sparrows (Passer domesticus). After exposing birds to stable warm, stable cold, or fluctuating cold temperatures, we found no significant differences in masses or metabolic rates between the stable and fluctuating cold groups. Compared to the warm treatment, both cold treatments had higher basal, but not summit (i.e., maximum, cold induced), metabolic rates. These results suggest that increasing temperature variability may not influence the maintenance costs or the thermoregulatory capacity of winter-phenotype house sparrows.

Shifting Precipitation Regimes Influence Optimal Germination Strategies and Population Dynamics in Bet-Hedging Desert Annuals

AbstractClimate change will affect both the mean and the variability in environmental conditions and may have major negative impacts on population densities in the future. For annual plants that already live in an extreme environment like the Sonoran Desert, keeping a fraction of their seeds dormant underground (for possibly years at a time) is critical to survive. Here, we consider how this form of bet hedging (i.e., delayed germination) for 10 Sonoran Desert annuals mediates responses to precipitation shifts. We use a demographic model parameterized with long-term field and precipitation data to explore how forecasted changes in precipitation impact annual plant species' population densities. We then examine how instantaneous evolution of optimal germination fractions in the shifted precipitation regimes bolsters population densities. Our results indicate that overall less rainfall and, to a lesser extent, increased variance in rainfall drive population levels down. Instantaneous evolution of optimal germination fractions in new regimes benefited species' populations only marginally, and only for small to moderate shifts in precipitation. Thus, even rapid evolution is unlikely to save populations experiencing larger shifts in precipitation. Finally, we predict that specialists that can capitalize on wet-year bonanzas or are water use efficient will be the most resilient to precipitation shifts as long as their seed survivorships are sufficiently high.

Spatio-temporal analysis of extreme air pollution and risk assessment

Extreme air pollution poses global health and environmental threats, necessitating robust policy interventions. This study first analyses the surface mass concentration of major aerosols (such as black carbon, organic carbon, dust, sea salts, and sulphates) to estimate global PM2.5 concentrations from 1980 to 2023. The developed model-estimated PM2.5 database was validated against data from 526 cities worldwide, showing strong accuracy, with RMSE, r, and R2 values of 7.47 μg/m³, 0.87, and 0.75, respectively. The motivation arises from the need to understand whether recent pollution increases are driven by rising emissions or natural variability, given the significant impacts on life and property. To assess both short-and long-term pollution trends, magnitudes, and risks, we proposed twelve novel extreme pollution indices, which comprehensively characterize the spatial and temporal variations in pollution. The highest PM2.5 concentrations were observed in regions near the Saharan Desert, reaching up to 90,000 μg/m³. However, significant PM2.5TOT (total pollution) concentrations were also found in the Indo-Gangetic Plain (IGP) and eastern China, ranging from 20,000 to 40,000 μg/m³. Persistent pollution burdens North Africa for approximately 350 days annually, while the IGP and eastern China experience extreme pollution for over 200 days yearly. Other pollution indices highlight the intensity and frequency of pollution in regions such as North Africa, IGP, Eastern Russia, Western USA, and Eastern China, revealing critical regional air quality challenges. Our analysis identifies cities in low-income and middle-income countries, such as New Delhi, Lahore, Dhaka, and Dammam, as being at extreme risk scores above 90 out of 100. Meanwhile, cities like Ghaziabad, Chongqing, Kolkata, Mumbai, and East London fall into the high-risk category, scoring between 60 and 80. Conversely, most cities in the EU, USA, and Canada are at very low risk, a result of the effective implementation of strategic air pollution norms and policies. The study promotes a phased approach for low- and middle-income regions, emphasizing achievable air quality standards, low-cost monitoring, targeted interventions, urban greening, public awareness, and innovative financing for improvements.

Precipitation in July maximizes total above-ground productivity of the desert steppe in Inner Mongolia, China

Precipitation distribution during the growing season and interannual precipitation variation may have significant impacts on grassland ecosystem productivity at the site level. To explore the effect of the distribution of precipitation on plant communities in the Inner Mongolian desert steppe dominated by Stipa breviflora, we analyzed monthly precipitation patterns during the growing season (May-October) over the past 60 years (1961-2020) and identified four major precipitation distribution patterns. These included the concentrated precipitation during July (TΛ7), August (TΛ8), and during the early and late growth stages. However, with precipitation being scarce during the boom (TM), the distribution resembled a normal distribution (T∩). Field experiments simulating the four distributions were conducted from May to October 2021. The results showed that the effects of the distribution of precipitation on plant species, diversity, and abundance were not significant; only the Pielou evenness showed a significant effect after July. The total above-ground net primary productivity (ANPP) of TΛ7 was 55.4% higher than those of the other three patterns, whereas the differences among the other three precipitation distributions were not significant. The annual forb Neopallasia pectinate was the primary contributor to the increased ANPP of TΛ7. These results suggest that the S. breviflora desert steppe achieved maximum productivity when the precipitation reached 41.6% of the annual average during July and satisfied the basic plant growth requirements during other months. This study emphasizes the implementation of management measures (irrigation or artificial precipitation) for maximizing forage yield and forecasting the plant composition in desert steppes.

Heat Wave Adaptations: Unraveling the Competitive Dynamics Between Invasive Wedelia trilobata and Native Wedelia chinensis

Heat waves (HW) are projected to become more frequent and intense with climate change, potentially enhancing the invasiveness of certain plant species. This study aims to compare the physiological and photosynthetic responses of the invasive Wedelia trilobata and its native congener Wedelia chinensis under simulated heat wave conditions (40.1 °C, derived from local historical data). Results show that W. trilobata maintained higher photosynthetic efficiency, water-use efficiency (WUE), and total biomass under HW, suggesting that its ability to optimize above-ground growth contributes to its success in heat-prone environments. In contrast, W. chinensis focused more on root development and antioxidant protection, exhibiting a decrease in total biomass under heat wave conditions. These results indicate that W. trilobata employs a more effective strategy to cope with heat stress, likely enhancing its competitive advantage in regions affected by heat waves. This study highlights the importance of understanding species-specific responses to extreme climate events and underscores the potential for heat waves to drive ecological shifts, favoring invasive species with higher phenotypic plasticity.

High sea surface temperatures were a prerequisite for the development and expansion of the Great Barrier Reef

The Great Barrier Reef is the largest reef system in the modern ocean. To date, the influence of temperature on the origin and long-term evolution of the Great Barrier Reef remains enigmatic. Here, we present a 900-thousand year TEX86H-derived temperature proxy record from Ocean Drilling Program Site 820 in the Coral Sea. It demonstrates that the onset of reef growth on the outer shelf was preceded by a rise in summer temperature from ~26° to ~28°C at around 700 thousand years ago (marine isotope stage 17). This approximately 2°C rise in summer sea surface temperatures (SSTs) likely resulted in higher carbonate production rates, which were crucial for the formation of the Great Barrier Reef. Subsequently, reconstructed SSTs remained sufficiently warm for the Great Barrier Reef to thrive and evolve continuously. The evolution of the Great Barrier Reef, therefore, appears to be closely linked to SSTs.

Stress of soil moisture and temperature exacerbates the toxicity of tire wear particles to soil fauna: Tracking the role of additives through host microbiota

Tire wear particles (TWPs) are considered as an emerging threat to soil fauna. However, how TWP toxicity to soil fauna responds to the stress of soil moisture and temperature remains unclear. We assessed the toxicity of environmentally relevant TWPs to the soil model species Enchytraeus crypticus under three soil moisture and two temperature gradients. Typical thermoplastic polypropylene (PP) was selected for comparison. Results showed that compared with PP, TWPs exerted stronger toxicity, including decreasing the worm growth, survival and reproduction rates, disturbing the soil and worm gut microbiota, and leaching more diverse and higher contents of additives. Stress of soil moisture and temperature exacerbated TWP toxicity mainly through affecting the leaching and transformation of additives. Fourteen mediated additives significantly contributed to the shift of the gut microbiota under soil moisture and temperature stress, among which 1,3-diphenylguanidine, N,N'-bis(methylphenyl)-1,4-benzenediamine quinone, N-tert-butyl-2-benzothiazolesulfenamide, and 2-aminobenzothiazole were identified as the main drivers. In addition, this study provided the first clear evidence that increased soil moisture and temperature promoted the transformation of additives in the soil. Our study revealed the non-negligible aggravated toxicity of TWPs to soil fauna under stress of soil moisture and temperature, providing novel insights into the environmental behavior of additives.

Soil carbon in the world's tidal marshes

Tidal marshes are threatened coastal ecosystems known for their capacity to store large amounts of carbon in their water-logged soils. Accurate quantification and mapping of global tidal marshes soil organic carbon (SOC) stocks is of considerable value to conservation efforts. Here, we used training data from 3710 unique locations, landscape-level environmental drivers and a global tidal marsh extent map to produce a global, spatially explicit map of SOC storage in tidal marshes at 30 m resolution. Here we show the total global SOC stock to 1 m to be 1.44 Pg C, with a third of this value stored in the United States of America. On average, SOC in tidal marshes' 0-30 and 30-100 cm soil layers are estimated at 83.1 Mg C ha-1 (average predicted error 44.8 Mg C ha-1) and 185.3 Mg C ha-1 (average predicted error 105.7 Mg C ha-1), respectively.

Community responses of testate amoebae (Arcellinida and Euglyphida) to ecological disturbance explained by contrasting assembly mechanisms in two subtropical reservoirs

Mechanisms underlying the effects of ecological disturbance on aquatic ecosystems remain uncertain in subtropical regions. Here, we used a proxy-based approach to explore the community dynamics of testate amoebae (Arcellinida and Euglyphida) in two subtropical deep reservoirs (Tingxi and Shidou) in Xiamen, southeastern China, over a three-year period. Specifically, we employed drought and typhoon events recorded by weather station as proxies for ecological disturbance and chlorophyll-a estimated through fluorometry as a proxy for testate amoeba food. We addressed three questions: (1) Does typhoon-induced ecological disturbance affect the distribution patterns of testate amoebae in subtropical reservoirs? (2) Do typhoon- and drought-induced ecological disturbances affect the testate amoeba community across different water layers of subtropical reservoirs similarly? (3) Do stochastic or deterministic processes shaping the testate amoeba community over time exhibit similar patterns in different water layers of subtropical reservoirs? The typhoon-induced ecological disturbance resulted in pronounced shifts in the distribution patterns of testate amoebae, characterized by lower shell influx in surface waters (11-12 ind. mL-1 d-1) and higher shell influx in middle and bottom waters (12-22 ind. mL-1 d-1). The impact of typhoon-and drought-induced ecological disturbance was more pronounced in surface waters, and its pure explanation accounted for 29.5-35.5 % community variation in a variation partitioning analysis. The effect of stochastic processes revealed by the neutral model increased with water depths, accounting for 63.3-76.5 % of the community variation in the surface, 77.4-82.6 % in the middle, and 82.8-88.1 % in the bottom water. The effect of deterministic processes shown by the null model decreased with water depth and remained relatively low across all water layers. These results suggest contrasting patterns of assembly mechanisms underlying the testate amoeba community responses to ecological disturbance, with the balance perhaps shaped by water depth and the average water residence time in a reservoir.

Climate Response and Radial Growth Dynamics of Pedunculate Oak (Quercus robur L.) Plus Trees and Their Half-Sib Progeny in Periods of Severe Droughts in the Forest-Steppe Zone of Eastern Europe

The dendrochronological parameters of 97 pedunculate oak (Quercus robur L.) trees including 20 plus trees (142-year-old on average) and four half-sib families for four of them were analyzed considering also specifically years of the most severe droughts that were identified using average monthly air temperature and precipitation data. The tree-ring width (TRW) was mostly affected by air temperature that had the largest cross-dating indices (CDI), up to 78% maximum. However, the 32-year Brückner-Egeson-Lockyer cycle (a climatic cycle of approximately 30-40 years that correlates with sunspot activity) was more reflected in the TRW dynamics in plus trees than precipitation and air temperature. A high-frequency of abnormal TRW was clearly observed during drought periods and in the following 2-3 years. Tree radial-growth reduction due to drought stress varied significantly between families. The resistance to drought based on TRW was higher in the maternal plus oak trees than in progeny. Drought resulted in reduced growth during the subsequent year(s); hence, the minimum growth occurred after the actual climate event. Autumn-winter precipitation and weather conditions were of the greatest importance at the onset of active vegetation in April and May. The influence of air temperature on oak growth was the largest in March (r = 0.39, p < 0.05). The strongest positive correlation between precipitation and growth (with r up to 0.38) was observed in May 2023. Plus trees had a high adaptive potential due to the stability of radial growth during drought with high resistance (Rt = 1.29) and resilience (Rs = 1.09) indexes. The offspring of families 1 (Rt = 0.89, Rs = 0.89) and 2 (Rt = 1.04, Rs = 0.87) had similar resistance and resilience, but the recovery indices (Rc) for offspring in families 1, 2 and 3 exceeded the recovery values for plus trees. For offspring in families 3 and 4, the index values were lower. The revealed responses of wood growth of plus trees to climatic parameters estimated as resistance (Rt), resilience (Rs) and recovery (Rc) indexes and similar responses in their progeny can be used in breeding pedunculate oak for wood growth productivity and drought resistance.

Hydro-climatic extremes shift the hydrologic sensitivity regime in a cold basin

Escalating climate extreme events disrupt hydrological processes by affecting both water availability and sediment dynamics. However, the interconnection between hydrological variability and climatic extremes remains underexplored, particularly in cold regions under a changing climate. Here, we develop a yield-based dichotomy framework to examine the impact of shifted climatic extreme patterns on hydrological regimes in the Ishikari River Basin (IRB), Hokkaido, Japan, which is a crucial area for local agriculture and urban development. Utilizing a modified Soil and Water Assessment Tool (SWAT) integrated with downscaled CMIP6-GCM climate projections under Shared Socioeconomic Pathways (SSPs) scenarios, we identified significant annual variability in water and sediment yields associated with extreme climate events. Hot-dry conditions correlate with lower water and sediment yields, whereas increased cold extremes may result in higher sediment yields across the IRB. Our findings also indicate that hotter and drier patterns interact with hydrological processes, potentially establishing new hydrologic regimes and shifting climatic extremes-induced thresholds for yield classification within the IRB. Notably, under SSP585, both water availability and sediment transport are projected to intensify, increasing flood risks and exacerbating sedimentation challenges. Our study highlights the urgent need for adaptive water management strategies to address these anticipated changes in hydrological regimes in response to global climate change.

The response of grey mouse lemurs to acute caloric restriction before reproduction supports the 'thrifty female hypothesis'

The 'thrifty female hypothesis' states that females preserve more of their energy reserves during winter than males because of the sex-specific time frame of energy allocation for reproduction. As males reactivate their reproductive axis before the mating period, while females mainly allocate energy during gestation and lactation, we hypothesized that males would have to use shorter torpor bouts and longer periods of normothermic activity to promote spermatogenesis during winter, a period of low food availability. Here, we applied an acute 2 week 80% caloric restriction in male and female grey mouse lemurs shortly before the mating period. We found evidence of thriftier phenotypes in wintering females, which performed deeper and longer torpor bouts than males and ultimately lost less body mass. Our results thus support the 'thrifty female hypothesis' in a seasonally breeding primate and reinforce the concept of a sex-biased trade-off in using torpor, which might ultimately benefit reproduction and survival.

How should climate actions be planned? Model lessons from published action plans

To effectively protect against the increasingly pervasive effects of climate change, countries and cities around the world are tasked with formulating and implementing climate actions that effectively respond to the challenges ahead. However, choosing the optimal climate actions is complex, since it is necessary to consider many external impacts as early on as the planning phase. Our novel methodology uncovers and integrates into first-of-its-kind decision support framework the identified climate actions of 443 European cities (from 32 countries) and the city structure-related features that influence the basic success of strategy creation into a first-of-its-kind decision support framework. Depending on their budget, population density, development and energy consumption portfolio, the results highlight that the analyzed European cities need to adopt a different way of thinking. The research results lay the foundation for the decision support of evidence-based climate action planning and contribute towards strengthening the role of cities worldwide in the fight against climate change in the future.

The impacts of diet on cardiac performance under changing environments

Natural and anthropogenic stressors are dramatically altering environments, impacting key animal physiological traits, including cardiac performance. Animals require energy and nutrients from their diet to support cardiac performance and plasticity; however, the nutritional landscape is changing in response to environmental perturbations. Diet quantity, quality and options vary in space and time across heterogeneous environments, over the lifetime of an organism and in response to environmental stressors. Variation in dietary energy and nutrients (e.g. lipids, amino acids, vitamins, minerals) impact the heart's structure and performance, and thus whole-animal resilience to environmental change. Notably, many animals can alter their diet in response to environmental cues, depending on the context. Yet, most studies feed animals ad libitum using a fixed diet, thus underestimating the role of food in impacting cardiac performance and resilience. By applying an ecological lens to the study of cardiac plasticity, this Commentary aims to further our understanding of cardiac function in the context of environmental change.

Artificial Intelligence for Climate Change Biology: From Data Collection to Predictions

In the era of big data, ecological research is experiencing a transformative shift, yet big-data advancements in thermal ecology and the study of animal responses to climate conditions remain limited. This review discusses how big data analytics and artificial intelligence (AI) can significantly enhance our understanding of microclimates and animal behaviors under changing climatic conditions. We explore AI's potential to refine microclimate models and analyze data from advanced sensors and camera technologies, which capture detailed, high-resolution information. This integration can allow researchers to dissect complex ecological and physiological processes with unprecedented precision. We describe how AI can enhance microclimate modeling through improved bias correction and downscaling techniques, providing more accurate estimates of the conditions that animals face under various climate scenarios. Additionally, we explore AI's capabilities in tracking animal responses to these conditions, particularly through innovative classification models that utilize sensors such as accelerometers and acoustic loggers. For example, the widespread usage of camera traps can benefit from AI-driven image classification models to accurately identify thermoregulatory responses, such as shade usage and panting. AI is therefore instrumental in monitoring how animals interact with their environments, offering vital insights into their adaptive behaviors. Finally, we discuss how these advanced data-driven approaches can inform and enhance conservation strategies. In particular, detailed mapping of microhabitats essential for species survival under adverse conditions can guide the design of climate-resilient conservation and restoration programs that prioritize habitat features crucial for biodiversity resilience. In conclusion, the convergence of AI, big data, and ecological science heralds a new era of precision conservation, essential for addressing the global environmental challenges of the 21st century.

Flavonoid Synthesis Pathway Response to Low-Temperature Stress in a Desert Medicinal Plant, Agriophyllum Squarrosum (Sandrice)

Background/Objectives:Agriophyllum squarrosum (L.) Moq. (A. squarrosum), also known as sandrice, is an important medicinal plant widely distributed in dunes across all the deserts of China. Common garden trials have shown content variations in flavonoids among the ecotypes of sandrice, which correlated with temperature heterogeneity in situ. However, there have not been any environmental control experiments to further elucidate whether the accumulation of flavonoids was triggered by cold stress; Methods: This study conducted a four-day ambient 4 °C low-temperature treatment on three ecotypes along with an in situ annual mean temperature gradient (Dulan (DL), Aerxiang (AEX), and Dengkou (DK)); Results: Target metabolomics showed that 12 out of 14 flavonoids in sandrice were driven by cold stress. Among them, several flavonoids were significantly up-regulated, such as naringenin and naringenin chalcone in all three ecotypes; isorhamnetin, quercetin, dihydroquercetin, and kaempferol in DL and AEX; and astragalin in DK. They were accompanied by 19 structural genes of flavonoid synthesis and 33 transcription factors were markedly triggered by cold stress in sandrice. The upstream genes, AsqAEX006535-CHS, AsqAEX016074-C4H, and AsqAEX004011-4CL, were highly correlated with the enrichment of naringenin, which could be fine-tuned by AsqAEX015868-bHLH62, AsqAEX001711-MYB12, and AsqAEX002220-MYB1R1; Conclusions: This study sheds light on how desert plants like sandrice adapt to cold stress by relying on a unique flavonoid biosynthesis mechanism that regulating the accumulation of naringenin. It also supports the precise development of sandrice for the medicinal industry. Specifically, quercetin and isorhamnetin should be targeted for development in DL and AEX, while astragalin should be precisely developed in DK.

Seasonality in embolism resistance and hydraulic capacitance jointly mediate hydraulic safety in branches and leaves of oriental cork oak (Quercus variabilis Bl.)

Seasonality in temperate regions is prominent during the era of increased climatic variability. A hydraulic trait that can adjust to seasonally changing climatic conditions is crucial for tree safety. However, little attention has been paid to the intraspecific seasonality of drought-related traits and hydraulic safety of keystone forest trees. We examined seasonal variations in the key morphological and physiological traits as well as multiple hydraulic safety margins (SMs) at the branch and leaf levels in oriental cork oak (Quercus variabilis Bl.), which is predominant in Chinese temperate forests. Pneumatic measurements indicated that, as seasons progressed, the water potential at which 50% of branch embolisms occur (P50_branch) decreased from -3.34 to -4.23 MPa, with a coefficient of variation (CV) of 9.08%. Sapwood capacitance ranged from 48.19 to 248.08 kg m-3 MPa-1, peaking in autumn and reaching minimum in winter (CV 60.58%). Rehydration kinetics confirmed higher leaf embolism vulnerability (P50_leaf) in spring and autumn than those in summer, with values ranging from -1.06 to -3.02 MPa (CV 39.85%). All leaf pressure-volume (PV) traits shifted with growth, with CVs ranging from 6.95% to 46.69%. Sapwood density had significant negative correlations with P50_branch and hydraulic capacitance for elastic water storage, whereas leaf mass per area was linearly associated with PV traits but not with P50_leaf. Furthermore, the branch typical SMs (difference between branch midday water potential and P50_branch) were consistently >1.84 MPa, and vulnerability segmentation was prevalent throughout, implying a plausible hydraulic foundation for the dominance of Q. variabilis. Diverse hydraulic response patterns existed across seasons, leading to positive SMs mediated by the aforementioned physiological traits. Although Q. variabilis exhibits a high level of hydraulic safety, its susceptibility to sudden summer droughts may increase due to global climate change.

Machine learning-based extreme event attribution

The observed increase in extreme weather has prompted recent methodological advances in extreme event attribution. We propose a machine learning-based approach that uses convolutional neural networks to create dynamically consistent counterfactual versions of historical extreme events under different levels of global mean temperature (GMT). We apply this technique to one recent extreme heat event (southcentral North America 2023) and several historical events that have been previously analyzed using established attribution methods. We estimate that temperatures during the southcentral North America event were 1.18° to 1.42°C warmer because of global warming and that similar events will occur 0.14 to 0.60 times per year at 2.0°C above preindustrial levels of GMT. Additionally, we find that the learned relationships between daily temperature and GMT are influenced by the seasonality of the forced temperature response and the daily meteorological conditions. Our results broadly agree with other attribution techniques, suggesting that machine learning can be used to perform rapid, low-cost attribution of extreme events.

Deep mitigation for trade-embodied carbon emissions among the Belt and Road Initiative countries

The frequent trade within and beyond the Belt and Road Initiative (BRI) has prospered the economy but has also expanded carbon emissions. Here, through a multi-regional environmental input-output analysis framework, we explore the patterns and inter-sectoral linkage of trade-embodied carbon emissions among BRI countries during 2015-2019. Then, a dynamic data envelopment analysis model considering carbon inequality as a non-discretionary input is constructed to assess the carbon emission efficiency of the identified key sector. We find that trade-embodied carbon emissions in the BRI steadily increased during 2015-2019. The manufacturing sector was identified as the key sector, exhibiting an overall efficiency of 0.6268 on average, with significant efficiency disparities. Moreover, we validate the positive role of efficiency enhancement in carbon emission mitigation, as well as the negative moderating effect of carbon inequality. Overall, this study provides optimal collaboration and initiatives to mitigate trade-embodied carbon emissions among BRI countries deeply.

The Invasive Plant Amaranthus spinosus L. Exhibits a Stronger Resistance to Drought than the Native Plant A. tricolor L. under Co-Cultivation Conditions When Treated with Light Drought

Drought may facilitate the invasion process of invasive plants, mainly because invasive plants can obtain a stronger growth competitiveness than native plants under drought. It is therefore imperative to illuminate the mechanisms underlying the successful invasion of invasive plants under drought, with a particular focus on the differences in the resistance of invasive and native plants to drought. This study aimed to elucidate the differences in the resistance between the invasive plant Amaranthus spinosus L. and the native plant A. tricolor L. to drought under a gradient of drought. The resistance of co-cultivated A. spinosus to drought was significantly higher than that of co-cultivated A. tricolor under light drought. Hence, A. spinosus may obtain a stronger competitive advantage than A. spinosus under co-cultivation conditions when treated with light drought. The resistance of the two plants to drought may be predominantly influenced by their height and biomass. This present study also defines a method for evaluating the stress resistance of a given plant species to stress by calculating the stress resistance index. This present study offers a robust theoretical foundation for determining the stress resistance of a given plant species and the environmental management of A. spinosus under drought.

Quantitative reconstruction of a single super rainstorm using daily resolved δ18O of land snail shells

A "once-in-a-millennium" super rainstorm battered Zhengzhou, central China, from 07/17/2021 to 07/22/2021 (named "7.20" Zhengzhou rainstorm). It killed 398 people and caused billions of dollars in damage. A pressing question is whether rainstorms of this intensity can be effectively documented by geological archives to understand better their historical variabilities beyond the range of meteorological data. Here, four land snail shells were collected from Zhengzhou, and weekly to daily resolved snail shell δ18O records from June to September of 2021 were obtained by gas-source mass spectrometry and secondary ion mass spectrometry. The daily resolved records show a dramatic negative shift between 06/18/2021 and 09/18/2021, which has been attributed to the "7.20" Zhengzhou rainstorm. Moreover, the measured amplitude of this shift is consistent with the theoretical value estimated from the flux balance model and instrumental data for the "7.20" Zhengzhou rainstorm. Our results suggest that the ultra-high resolution δ18O of land snail shells have the potential to reconstruct local synoptic scale rainstorms quantitatively, and thus fossil snail shells in sedimentary strata can be valuable material for investigating the historical variability of local rainstorms under different climate backgrounds.

Vegetation growth responses to climate change: A cross-scale analysis of biological memory and time lags using tree ring and satellite data

Vegetation growth is affected by past growth rates and climate variability. However, the impacts of vegetation growth carryover (VGC; biotic) and lagged climatic effects (LCE; abiotic) on tree stem radial growth may be decoupled from photosynthetic capacity, as higher photosynthesis does not always translate into greater growth. To assess the interaction of tree-species level VGC and LCE with ecosystem-scale photosynthetic processes, we utilized tree-ring width (TRW) data for three tree species: Castanopsis eyrei (CE), Castanea henryi (CH, Chinese chinquapin), and Liquidambar formosana (LF, Chinese sweet gum), along with satellite-based data on canopy greenness (EVI, enhanced vegetation index), leaf area index (LAI), and gross primary productivity (GPP). We used vector autoregressive models, impulse response functions, and forecast error variance decomposition to analyze the duration, intensity, and drivers of VGC and of LCE response to precipitation, temperature, and sunshine duration. The results showed that at the tree-species level, VGC in TRW was strongest in the first year, with an average 77% reduction in response intensity by the fourth year. VGC and LCE exhibited species-specific patterns; compared to CE and CH (diffuse-porous species), LF (ring-porous species) exhibited stronger VGC but weaker LCE. For photosynthetic capacity at the ecosystem scale (EVI, LAI, and GPP), VGC and LCE occurred within 96 days. Our study demonstrates that VGC effects play a dominant role in vegetation function and productivity, and that vegetation responses to previous growth states are decoupled from climatic variability. Additionally, we discovered the possibility for tree-ring growth to be decoupled from canopy condition. Investigating VGC and LCE of multiple indicators of vegetation growth at multiple scales has the potential to improve the accuracy of terrestrial global change models.

Temporal patterns in multiple stressors shape the vulnerability of overwintering Arctic zooplankton

The Arctic polar nights bring extreme environmental conditions characterised by cold and darkness, which challenge the survival of organisms in the Arctic. Additionally, multiple anthropogenic stressors can amplify the pressure on the fragile Arctic ecosystems during this period. Determining how multiple anthropogenic stressors may affect the survival of Arctic life is crucial for ecological risk assessments and management, but this topic is understudied. For the first time, our study investigates the complex interactions of multiple stressors, exploring stressor temporal dynamics and exposure duration on a key Arctic copepod Calanus glacialis during the polar nights. We conducted experiments with pulse (intermittent) and press (continuous) exposure scenarios, involving microplastics, pyrene and warming in a fully factorial design. We observed significant effects on copepod survival, with pronounced impacts during later stressor phases. We also detected two-way interactions between microplastics and pyrene, as well as pyrene and warming, further intensified with the presence of a third stressor. Continuous stressor exposure for 9 days (press-temporal scenario) led to greater reductions in copepod survival compared to the pulse-temporal scenario, characterised by two 3-day stressor exposure phases. Notably, the inclusion of recovery phases, free from stressor exposure, positively influenced copepod survival, highlighting the importance of temporal exposure dynamics. We did not find behaviour to be affected by the different treatments. Our findings underscore the intricate interactions amongst multiple stressors and their temporal patterns in shaping the vulnerability of overwintering Arctic copepods with crucial implications for managing Arctic aquatic ecosystems under the fastest rate of ongoing climate change on earth.

Responses of non-native and native plant species to fluctuations of water availability in a greenhouse experiment

Water availability strongly influences the survival, growth, and reproduction of most terrestrial plant species. Experimental evidence has well documented the effect of changes in total amount of water availability on non-native vs. native plants. However, little is known about how fluctuations in water availability affect these two groups, although more extreme fluctuations in water availability increasingly occur with prolonged drought and extreme precipitation events. Here, we grew seven non-native and seven native plant species individually in the greenhouse. Then, we exposed them to four watering treatments, each treatment with the same total amount of water, but with different divisions: W1 (added water 16 times with 125 mL per time), W2 (8 times, 250 mL per time), W3 (4 times, 500 mL per time), and W4 (2 times, 1000 mL per time). We found that both non-native and native plants produced the most biomass under medium frequency/magnitude watering treatments (W2 and W3). Interestingly, non-native plants produced 34% more biomass with the infrequent, substantial watering treatment (W4) than with frequent, minor watering treatment (W1), whereas native plants showed opposite patterns, producing 26% more biomass with W1 than with W4. Differences in the ratio of root to shoot under few/large and many/small watering treatments of non-native vs. native species probably contributed to their different responses in biomass production. Our results advance the current understanding of the effect of water availability on non-native plants, which are affected not only by changes in amount of water availability but also by fluctuations in water availability. Furthermore, our results indicate that an increased few/large precipitation pattern expected under climate change conditions might further promote non-native plant invasions. Future field experiments with multiple phylogenetically controlled pairs of non-native and native species will be required to enhance our understanding of how water availability fluctuations impact on non-native invasions.

How modularity and heterotrophy complicate the understanding of the causes of thermal performance curves: the case of feeding rate in a filter-feeding animal

Warming global temperatures have consequences for biological rates. Feeding rates reflect the intake of energy that fuels survival, growth and reproduction. However, temperature can also affect food abundance and quality, as well as feeding behavior, which all affect feeding rate, making it challenging to understand the pathways by which temperature affects the intake of energy. Therefore, we experimentally assessed how clearance rate varied across a thermal gradient in a filter-feeding colonial marine invertebrate (the bryozoan Bugula neritina). We also assessed how temperature affects phytoplankton as a food source, and zooid states within a colony that affect energy budgets and feeding behavior. Clearance rate increased linearly from 18°C to 32°C, a temperature range that the population experiences most of the year. However, temperature increased algal cell size, and decreased the proportion of feeding zooids, suggesting indirect effects of temperature on clearance rates. Temperature increased polypide regression, possibly as a stress response because satiation occurred quicker, or because phytoplankton quality declined. Temperature had a greater effect on clearance rate per feeding zooid than it did per total zooids. Together, these results suggest that the effect of temperature on clearance rate at the colony level is not just the outcome of individual zooids feeding more in direct response to temperature but also emerges from temperature increasing polypide regression and the remaining zooids increasing their feeding rates in response. Our study highlights some of the challenges for understanding why temperature affects feeding rates, especially for understudied, yet ecologically important, marine colonial organisms.

Effects of periodic heat events on the reproduction and longevity of female and male Agasicles hygrophila (Coleoptera: Chrysomelidae)

Alternanthera philoxeroides (Amaranthaceae), commonly known as alligator weed, is a globally invasive and detrimental perennial weed. Agasicles hygrophila serves as an important biocontrol agent for alligator weeds. However, during mid-summer, when temperatures increase, A. hygrophila populations experience a significant decline, leading to ineffective weed control. This study has examined the impact of periodic heat events on the reproduction and survival of A. hygrophila females and males using various mating combinations and durations of temperature treatments. The results demonstrated significant effects on all of the studied parameters across mating combinations when compared with the control. Under the same temperature combination, the fecundity and survival rates of females, as well as the egg-hatching rate, decreased significantly with increasing repeated heat exposure. Furthermore, the egg-hatching rate varied significantly among different temperatures and time-interval combinations. In addition, the females displayed greater sensitivity to heat stress than males in terms of fecundity. These findings enhance our understanding of A. hygrophila population dynamics during summer and provide insights into the release of biocontrol agents in diverse regions with varying climates.

Nitrogen addition alleviates the adverse effects of drought on plant productivity in a temperate steppe

Drought and nitrogen enrichment could profoundly affect the productivity of semiarid ecosystems. However, how ecosystem productivity will respond to different drought scenarios, especially with a concurrent increase in nitrogen availability, is still poorly understood. Using data from a 4-year field experiment conducted in a semiarid temperate steppe, we explored the responses of aboveground net primary productivity (ANPP) to different drought scenarios and nitrogen addition, and the underlying mechanisms linking soil properties, plant species richness, functional diversity (community-weighted means of plant traits, functional dispersion) and phylogenetic diversity (net relatedness index) to ANPP. Our results showed that completely excluding precipitation in June (1-month intense drought) and reducing half the precipitation amount from June to August (season-long chronic drought) both significantly reduced ANPP, with the latter having a more negative impact on ANPP. However, reducing half of the precipitation frequency from June to August (precipitation redistribution) had no significant effect on ANPP. Nitrogen addition increased ANPP irrespective of drought scenarios. ANPP was primarily determined by soil moisture and nitrogen availability by regulating the community-weighted means of plant height, rather than other aspects of plant diversity. Our findings suggest that precipitation amount is more important than precipitation redistribution in influencing the productivity of temperate steppe, and nitrogen supply could alleviate the adverse impacts of drought on grassland productivity. Our study advances the mechanistic understanding of how the temperate grassland responds to drought stress, and implies that management strategies to protect tall species in the community would be beneficial for maintaining the productivity and carbon sequestration of grassland ecosystems under climate drought.

Bumble bee responses to climate and landscapes: Investigating habitat associations and species assemblages across geographic regions in the United States of America

Bumble bees are integral pollinators of native and cultivated plant communities, but species are undergoing significant changes in range and abundance on a global scale. Climate change and land cover alteration are key drivers in pollinator declines; however, limited research has evaluated the cumulative effects of these factors on bumble bee assemblages. This study tests bumble bee assemblage (calculated as richness and abundance) responses to climate and land use by modeling species-specific habitat requirements, and assemblage-level responses across geographic regions. We integrated species richness, abundance, and distribution data for 18 bumble bee species with site-specific bioclimatic, landscape composition, and landscape configuration data to evaluate the effects of multiple environmental stressors on bumble bee assemblages throughout 433 agricultural fields in Florida, Indiana, Kansas, Kentucky, Maryland, South Carolina, Utah, Virginia, and West Virginia from 2018 to 2020. Distinct east versus west groupings emerged when evaluating species-specific habitat associations, prompting a detailed evaluation of bumble bee assemblages by geographic region. Maximum temperature of warmest month and precipitation of driest month had a positive impact on bumble bee assemblages in the Corn Belt/Appalachian/northeast, southeast, and northern plains regions, but a negative impact on the mountain region. Further, forest land cover surrounding agricultural fields was highlighted as supporting more rich and abundant bumble bee assemblages. Overall, climate and land use combine to drive bumble bee assemblages, but how those processes operate is idiosyncratic and spatially contingent across regions. From these findings, we suggested regionally specific management practices to best support rich and abundant bumble bee assemblages in agroecosystems. Results from this study contribute to a better understanding of climate and landscape factors affecting bumble bees and their habitats throughout the United States.

Contrasting nidification behaviors facilitate diversification and colonization of the Music frogs under a changing paleoclimate

In order to cope with the complexity and variability of the terrestrial environment, amphibians have developed a wide range of reproductive and parental behaviors. Nest building occurs in some anuran species as parental care. Species of the Music frog genus Nidirana are known for their unique courtship behavior and mud nesting in several congeners. However, the evolution of these frogs and their nidification behavior has yet to be studied. With phylogenomic and phylogeographic analyses based on a wide sampling of the genus, we find that Nidirana originated from central-southwestern China and the nidification behavior initially evolved at ca 19.3 Ma but subsequently lost in several descendants. Further population genomic analyses suggest that the nidification species have an older diversification and colonization history, while N. adenopleura complex congeners that do not exhibit nidification behavior have experienced a recent rapid radiation. The presence and loss of the nidification behavior in the Music frogs may be associated with paleoclimatic factors such as temperature and precipitation. This study highlights the nidification behavior as a key evolutionary innovation that has contributed to the diversification of an amphibian group under past climate changes.