Search

Societal Impact Statement: Rice wild relatives (RWR) provide valuable genetic resources for modern rice breeding, yet knowledge gaps constrain their conservation and further utilization. To address these gaps, the potential distributions of 22 RWR taxa were modeled, and their conservation statuses were assessed. Most taxa were identified as medium priority for further conservation. Further ex‐situ collecting hotspots are in Southeast and South Asia, Northern Australia, West Africa, and tropical Americas, while habitat protection lies in Southeast and South Asia, Northern Australia, and West Africa. Climate change may shift equatorial habitats to higher latitudes and mountain habitats to higher altitudes. Summary: Rice wild relatives (RWR) provide valuable genetic resources for modern rice breeding. However, knowledge gaps on their geographic distributions and conservation status constrain their conservation and further utilization.To fill these critical gaps, we modeled the potential distributions of 22 RWR taxa under current climate scenarios, assessed their conservation status, both ex situ (in genebanks or botanical gardens) and in situ (in protected areas), and examined changes in taxa richness of RWR in predicted areas under future climate scenarios.The RWR were primarily distributed in tropical Asia to tropical Australia, tropical Africa, and South and Central America. We identified 4 out of 22 taxa as high priority (HP) for further conservation action and 18 taxa as medium priority (MP).Hotspots requiring further collecting for ex situ conservation are concentrated in Southeast and South Asia, Northern Australia, West Africa, and tropical Americas. Meanwhile, habitat protection should be enhanced in Southeast and South Asia, Northern Australia, and West Africa. Under future climate change, suitable habitats near the equator are expected to shift toward higher latitudes and some in lower‐latitude basins may become unsuitable due to excessive heat, resulting in decreased taxa richness in these areas. Additionally, suitable habitats in high mountain areas may shift to higher altitudes, potentially augmenting taxa richness in the highlands. Our findings provide vital insights to guide future rescue conservation efforts for RWR. [ABSTRACT FROM AUTHOR]

Aims: The Middle East, located in the arid belt of the Earth, is home to a diverse range of biodiversity, with its mountain ecosystems being the most important centres of species diversity and endemism. In this study, the impact of climate change on alpine bird species in the Middle East was assessed across five mountain systems: Alborz–Kopet‐Dagh, Caucasus–Pontic, Levant–Taurus, Sarawat–Hijaz and Zagros–Central Iran. Location: Middle East. Methods: Using species distribution models (SDMs), 38 native alpine bird species were analysed under different climate change scenarios. We also identified future multispecies in situ and ex situ climate refugia and assessed the efficiency of the current protected areas (PAs) system in protecting them. Results: The results indicated that, on average, habitat suitability for these species is projected to decline by 36.83% (2050, SSP2‐4.5) to 60.10% (2070, SSP5‐8.5) with an upward range shift. Based on stacking range change of the species, Levant–Taurus, Zagros–Central Iran and Alborz–Kopet–Dagh mountain ranges will experience the highest amount of habitat loss, respectively, with Caucasus–Pontic being least affected. The gap analysis showed that the existing PAs system covers only 13% and 10% of the in situ and ex situ climatic refugia, respectively. Conclusions: Our findings underscore the significance of mountainous regions in the Middle East for the persistence of alpine bird species and the urgent need to prioritize climate refugia in transboundary and participatory conservation plans. It is crucial to prevent habitat degradation and alteration resulting from human activities in these areas to ensure the persistence of alpine species and their habitats. [ABSTRACT FROM AUTHOR]

Environmental factors impact species richness differently across taxonomic groups, and understanding the geographic patterns and drivers influencing alpine plant richness remains limited. This study compiled global distribution data of 404 species of Gentiana, an alpine genus, and analyzed the relative effects of different environmental factors and several previously proposed models on the variation of Gentiana richness. By evaluating the effects of range size and regions on the relationships between Gentiana richness and environmental factors, we found that all tested environmental factors had weak effects on richness variation for all species and wide‐ranging species, while habitat heterogeneity was the best predictor for narrow‐ranging species. Habitat heterogeneity was the main driver of richness variation in Europe and Asia, but not in North America. The multiple regression model that included variables for energy, water, seasonality, habitat heterogeneity and past climate change had the highest explanatory power, but it still explained less than 50% of the variation in species richness for all Gentiana species at both global and regional scale, except for Europe. The limited explanatory power of environmental factors in explaining species richness patterns for all species, along with the variations observed among regions, suggest that other factors, such as evolutionary processes and biogeographic history may have also influenced the geographic patterns of Gentiana species richness. In conclusion, our results indicate a limited influence of climate factors on alpine species richness, while habitat heterogeneity, along with its impacts on speciation and dispersal, likely play significant roles in shaping the richness of alpine Gentiana species. [ABSTRACT FROM AUTHOR]

Warming and precipitation anomalies affect terrestrial carbon balance partly through altering microbial eco-physiological processes (e.g., growth and death) in soil. However, little is known about how such processes responds to simultaneous regime shifts in temperature and precipitation. We used the 18O-water quantitative stable isotope probing approach to estimate bacterial growth in alpine meadow soils of the Tibetan Plateau after a decade of warming and altered precipitation manipulation. Our results showed that the growth of major taxa was suppressed by the single and combined effects of temperature and precipitation, eliciting 40-90% of growth reduction of whole community. The antagonistic interactions of warming and altered precipitation on population growth were common (~70% taxa), represented by the weak antagonistic interactions of warming and drought, and the neutralizing effects of warming and wet. The members in Solirubrobacter and Pseudonocardia genera had high growth rates under changed climate regimes. These results are important to understand and predict the soil microbial dynamics in alpine meadow ecosystems suffering from multiple climate change factors. [ABSTRACT FROM AUTHOR]

Mountain forests provide multiple benefits but are threatened by climate change-induced forest dieback. Although many studies summarize perceptions of forest ecosystem services, relatively few deal with mountain forests. The local population's perception of forest dieback in mountain forests in relation to climate change has rarely been investigated so far. Their perspective is relevant as local people are often deeply attached to "their" forests, they actively use forest ecosystems and—as voters and taxpayers—they need to support the state's adaptation and funding measures. Therefore, this study investigates the climate change and forest dieback perception of local inhabitants in two mountain areas of Southern Germany (the German Alps and the Bavarian Forest) with a quantitative survey based on representative online samples (n = 709). Relying conceptually on van der Linden's (J Environ Psychol 41:112–124, 2015. https://doi.org/10.1016/j.jenvp.2014.11.012) climate change risk perception model, the results show that experiential processing, cognitive and socio-cultural factors are related to locals' forest dieback and climate change perception, while socio-demographics show no or few connections. Nearly two-thirds (64.7%) of the respondents perceive moderate to strong forest dieback, while more than half (55.0%) of the respondents already observe consequences of climate change. The perceptions of climate change and forest dieback are positively correlated with medium to high strength. This shows that forest dieback could be interpreted as an indicator of climate change, which is difficult to observe due to its long-term nature. We identify three groups of respondents regarding preferred forest adaptation strategies to climate change. In general, respondents support nature-based forest adaptation strategies over intense measures. [ABSTRACT FROM AUTHOR]

Microhabitat utilisation holds a pivotal role in shaping a species' ecological dynamics and stands as a crucial concern for effective conservation strategies. Despite its critical importance, microhabitat use has frequently been addressed as static, centering on microhabitat preference. Yet, a dynamic microhabitat use that allows individuals to adjust to fine-scale spatio-temporal prey fluctuations, becomes imperative for species thriving in challenging environments. High-elevation ecosystems, marked by brief growing seasons and distinct abiotic processes like snowmelt, winds, and solar radiation, feature an ephemeral distribution of key resources. To better understand species' strategies in coping with these rapidly changing environments, we delved into the foraging behaviour of the white-winged snowfinch Montifringilla nivalis, an emblematic high-elevation passerine. Through studying microhabitat preferences during breeding while assessing invertebrate prey availability, we unveiled a highly flexible microhabitat use process. Notably, snowfinches exhibited specific microhabitat preferences, favoring grass and melting snow margins, while also responding to local invertebrate availability. This behaviour was particularly evident in snow-associated microhabitats and less pronounced amid tall grass. Moreover, our investigation underscored snowfinches' fidelity to foraging sites, with over half located within 10 m of previous spots. This consistent use prevailed in snow-associated microhabitats and high-prey-density zones. These findings provide the first evidence of dynamic microhabitat use in high-elevation ecosystems and offer further insights into the crucial role of microhabitats for climate-sensitive species. They call for multi-faceted conservation strategies that go beyond identifying and protecting optimal thermal buffering areas in the face of global warming to also encompass locations hosting high invertebrate densities. [ABSTRACT FROM AUTHOR]

Viruses are major players in the biosphere, yet little is known about their dynamics and life strategies in alpine lakes, particularly those on the Tibetan Plateau. We investigated microbial abundance, viral dynamics, and viral life strategies in 10 high‐altitude Tibetan lakes and found that they harbor high levels of active viruses. Salinity was identified as a crucial factor influencing viral abundance, dynamics, as well as viral life strategies. Lytic and lysogenic viral productions in moderate‐ and high‐salinity lakes were significantly higher than those in freshwater lakes. A trade‐off between viral life strategies resulted in a switch from lysis to lysogeny in high‐salinity lakes. Virus‐mediated cell lysis and virus decay in sampled Tibetan lakes could release about 162.72 and 2.84 μg C L−1 d−1, respectively. These findings revealed the crucial role of viruses in the carbon cycle of Tibetan lakes, and a switch in viral life strategies may impact their contribution to the carbon cycle. The potential impact of salinity changes triggered by climate change on the carbon cycle in alpine lakes worldwide is highlighted. [ABSTRACT FROM AUTHOR]

Bangladesh and northeast India are the most densely populated regions in the world where severe floods as a result of extreme rainfall events kill hundreds of people and cause socio‐economic losses regularly. Owing to local high topography, the moisture‐carrying monsoon winds converge near southeast Bangladesh (SEB) and northeast Bangladesh and India (NEBI), which produces significant extreme rainfall events from May to October. Using observed data, we find an increasing trend of 1‐day extreme event (>$$ > $$150 mm·$$ \cdotp $$day −1$$ {}^{-1} $$) frequency during 1950–2021. The extreme rainfall events quadrupled over western Meghalaya (affecting NEBI) and coastal SEB during this period. Composite analysis indicates that warm Bay of Bengal sea‐surface temperature intensifies the lower tropospheric moisture transport and flux through the low‐level jet (LLJ) to inland, where mountain‐forced moisture converges and precipitates as rainfall during extreme events. To understand the role of climate change, we use high‐resolution downscaled models from Coupled Model Intercomparison Project phase 6 (CMIP6). We find that the monsoon extreme event increase is ongoing and the region of quadrupled events further extends over the NEBI and SEB in the future (2050–2079) compared with historical simulations (1950–1979). A quadrupling of the intense daily moisture transport episodes due to increased LLJ instability, a northward shift of LLJ, and increased moisture contribute to the increased future extreme events. This dynamic process causes moisture to be transported to the NEBI from the southern Bay of Bengal, and the local thermodynamic response to climate change contributes to the increased extreme rainfall events. The CMIP6 projection indicates that more devastating flood‐causing extreme rainfall events will become more frequent in the future. [ABSTRACT FROM AUTHOR]

Questions: Climate change may have different effects on species richness depending on regional climates, soil types and the functional composition of local communities. Location: Subalpine belt of the Grandes Rousses (Alps) and Sancy mountain ranges (the Massif Central), France. Methods: We compared changes in species richness in response to recent climate change in communities from two mountain ranges subjected to contrasting environmental conditions, with a more continental climate and drier soils in the Alps than in the Massif Central. Vegetation composition of 189 and 157 plots was assessed in 1997 and 2017–2018 in the Alps and 1988–1989 and 2022 in the Massif Central, respectively. Five species traits (height, lateral spread, leaf area, specific leaf area and leaf dry matter content) were measured on 108 and 144 species, respectively. Changes in vegetation composition and species richness along spatial environmental gradients were analysed with correspondence analysis at the Sancy site and canonical correspondence analysis at the Alpe d'Huez site. Changes in functional composition across sites were analysed with principal components analysis. Changes in species richness with climate change were analysed with repeated‐measure ANOVAs. Results: In both mountain ranges summer temperatures increased and the hydric balance decreased over the past three decades, but snow cover duration decreased in the Alps only, whereas irradiance strongly increased in the Massif Central only. Functional composition was characterized by shorter and more conservative species in the Alps than in the Massif Central, which was dominated by tall exploitative species. Species richness overall decreased with climate change by ca 10% in the Alps but overall increased by ca 10% in the Massif Central. Species richness decreased in the Alps probably because of increasing competition induced by dwarf shrub encroachment due to decreasing snow cover duration, whereas species richness increased in the Massif Central probably due to increasing irradiance in a very nebulous climate. Conclusion: The opposite changes in species richness observed in the two mountain ranges with recent climate change were likely to be explained by their contrasting climate and soil conditions driving different functional compositions and diversity–environment relationships. [ABSTRACT FROM AUTHOR]

In addition to serving as North China's water supply and ecological barrier, the mountainous area of the Haihe River basin (MHRB) is a crucial location for the application of ecological engineering. Vegetation is an important component in the ecological conservation and eco-hydrological progress of the MHRB. A better understanding of regional vegetation growth can be achieved by a thorough investigation of vegetation indicators. In this research, the leaf area index (LAI) and gross primary productivity (GPP) were chosen as vegetation indicators. The characteristics and driving forces of the spatiotemporal variations of LAI and GPP in the MHRB were explored through Sen's slope, the Mann–Kendall test, the optimal parameter-based geographical detector model, and correlation analysis. From 2001 to 2018, the annual LAI and GPP increased significantly on the regional scale. The areas with significantly increased vegetation accounted for more than 81% of the MHRB. Land use was the most influential element for the spatial heterogeneity of LAI and GPP, and the humidity index was the most crucial one among climate indicators. Non-linear enhancement or bivariate enhancement was discovered between any two factors, and the strongest interaction was from land use and humidity index. The lowest vegetation cover was found in dry regions with annual precipitation below 407 mm and the humidity index under 0.41; while in both forests and large undulating mountains, higher LAI and GPP were observed. About 87% of the significantly increased vegetation was found in areas with unaltered land use. The increase in vegetation in the MHRB from 2001 to 2018 was promoted by the increased precipitation and humidity index and the reduced vapor pressure deficit. The sensitivity of GPP to climate change was stronger than that of LAI. These findings can serve as a theoretical guide for the application of ecological engineering and ecological preservation in the MHRB. [ABSTRACT FROM AUTHOR]

One of the ways in which plants are responding to climate change is by shifting their ranges to higher elevations. Early life‐history stages are major bottlenecks for species' range shifts, and variation in seedling emergence and establishment success can therefore be important determinants of species' ability to establish at higher elevations. Previous studies have found that warming per se tends to not only increase seedling establishment in alpine climates but it also increases plant productivity, which could limit establishment success through increased competition for light. Here we disentangle the relative importance of several climate‐related abiotic and biotic factors on sub‐alpine species' seedling emergence and survival in the alpine. Specifically, we test how temperature, precipitation and competition from neighbouring vegetation impacts establishment, and also whether species' functional traits, or strategies impact their ability to colonise alpine locations. We found that our six sub‐alpine study species were all able to recruit from seed in alpine locations under the extant alpine climate, but their emergence was limited by competition from neighbouring vegetation. This indicates that biotic interactions can hinder the range shifts expected as a result of climate warming. Species with a resource conservative strategy had higher emergence in the extant alpine climate than species with a resource acquisitive strategy, and they were largely unaffected by changes in temperature. The resource acquisitive species, in contrast, had faster emergence under warming, especially when they were released from competition from neighbouring vegetation. Our results indicate that competition from the established vegetation is limiting the spread of lowland species into the alpine, and as the climate continues to warm, species with resource acquisitive traits might gain an advantage. [ABSTRACT FROM AUTHOR]

Climate over the Tibetan Plateau (TP) has undergone substantial changes in recent decades due to its sensitive to global climate change. Regional land-atmosphere interactions are closely linked to the changes that have emerged across the TP. The TP is recognized as an ideal natural laboratory for monitoring ongoing climate changes and examining the mechanisms of land-atmosphere interactions over this high mountain region with diverse landscapes. Current models and satellites are struggle to accurately depict the interactions, critical field observations on land-atmosphere interactions here therefore provide necessitate independent validation data and fine-scale process insights for constraining reanalysis products, remote sensing retrievals, and land surface model parameterizations. Scientific data sharing is crucial 45 for the TP since acquiring critical field observations under this diverse topography and harsh conditions is challenging. However, in-situ observations are currently scattered among individuals or small groups and have yet to be integrated for comprehensive analysis, preventing a better understanding of the interactions, the unprecedented changes they generate, and the substantial massive ecological and environmental consequences they bring about. Here, we collaborated with different agencies and organizations to present a comprehensive dataset for hourly measurements of surface energy balance components, soil hydrothermal properties, and near-surface micrometeorological conditions spanning up to 17 years (2005-2021). This dataset is compiled from 12 field stations covering typical TP landscapes, and represents the most extensive in-situ observation data available for studying land-atmosphere interactions on the TP to date in terms of both spatial coverage and duration. To assure data quality, a set of rigorous data processing and quality control procedures are implemented for all observation elements in this dataset. The operational workflow and procedures are individually tailored to the varied types of elements at each station, including automated error screening, manual inspection, diagnostic checking, adjustments, and quality flagging. The hourly data series, the quality-assured data, and supplementary information including data integrity and the percentage of correct data on a monthly scale are provided via the National Tibetan Plateau Data Center (https://doi.org/10.11888/Atmos.tpdc.300977, Ma et al., 2023). The current dataset provides the benchmark constraints needed to both evaluate and improve the land surface models, reanalysis products, and remote sensing retrievals. Additionally, it is capable of characterizing fine-scale processes for land-atmosphere interactions of the TP and the underlying influence mechanisms. [ABSTRACT FROM AUTHOR]

Observations and model simulations have confirmed that the higher percentiles of precipitation intensity of all wet days have increased with the local daily dewpoint temperature at the Clausius–Clapeyron (C-C) rate of 7% °C−1 using the binning technique over China. It is uncertain whether the binning scaling rates will remain constant in the future climate. Here, we use daily precipitation and dewpoint temperature (DPT) over China from 20 CMIP6 models to examine and project the change of binning scaling of precipitation extremes. The results of the study suggest that the multimodel ensemble median (MEM) generally captures the spatial distribution of binning scaling rates and binning curves in different climate zones across China. The binning scaling rates have stability in the future but with a large increasing trend (more than 30%) in southeast China in the far future (2061–2100) under the SSP5-8.5 scenario. CMIP6 models project that both the peak of extreme precipitation and the temperature for the plateau mountain zone will increase in the far future under the SSP5-8.5 scenario, implying that the peak structure does not provide an upper limit for future precipitation extremes. Significance Statement: The binning scaling rates describe the relationship between precipitation extremes and temperature based on their day-to-day variations. However, it is still unclear whether the binning scaling rates of daily precipitation extremes with daily temperature will change in the future. We use 20 CMIP6 models to project the scaling rates of precipitation extremes with dewpoint temperature over China in the future. The results show that the sensitivity of precipitation extremes to dewpoint temperature will generally be stable, except that southeast China shows an increasing trend of up to 30%. Moreover, the peak of extreme precipitation and the temperature will increase with warming in the plateau mountain zone. Our results have implications for precipitation prediction and risk assessment. [ABSTRACT FROM AUTHOR]

Mountain forests are plant diversity hotspots, but changing climate and increasing forest disturbances will likely lead to far‐reaching plant community change. Projecting future change, however, is challenging for forest understory plants, which respond to forest structure and composition as well as climate. Here, we jointly assessed the effects of both climate and forest change, including wind and bark beetle disturbances, using the process‐based simulation model iLand in a protected landscape in the northern Alps (Berchtesgaden National Park, Germany), asking: (1) How do understory plant communities respond to 21st‐century change in a topographically complex mountain landscape, representing a hotspot of plant species richness? (2) How important are climatic changes (i.e., direct climate effects) versus forest structure and composition changes (i.e., indirect climate effects and recovery from past land use) in driving understory responses at landscape scales? Stacked individual species distribution models fit with climate, forest, and soil predictors (248 species currently present in the landscape, derived from 150 field plots stratified by elevation and forest development, overall area under the receiving operator characteristic curve = 0.86) were driven with projected climate (RCP4.5 and RCP8.5) and modeled forest variables to predict plant community change. Nearly all species persisted in the landscape in 2050, but on average 8% of the species pool was lost by the end of the century. By 2100, landscape mean species richness and understory cover declined (−13% and −8%, respectively), warm‐adapted species increasingly dominated plant communities (i.e., thermophilization, +12%), and plot‐level turnover was high (62%). Subalpine forests experienced the greatest richness declines (−16%), most thermophilization (+17%), and highest turnover (67%), resulting in plant community homogenization across elevation zones. Climate rather than forest change was the dominant driver of understory responses. The magnitude of unabated 21st‐century change is likely to erode plant diversity in a species richness hotspot, calling for stronger conservation and climate mitigation efforts. [ABSTRACT FROM AUTHOR]

Climate change has induced substantial shifts in vegetation boundaries such as alpine treelines and shrublines, with widespread ecological and climatic influences. However, spatial and temporal changes in the upper elevational limit of alpine grasslands ("alpine grasslines") are still poorly understood due to lack of field observations and remote sensing estimates. In this study, taking the Tibetan Plateau as an example, we propose a novel method for automatically identifying alpine grasslines from multi‐source remote sensing data and determining their positions at 30‐m spatial resolution. We first identified 2895 mountains potentially having alpine grasslines. On each mountain, we identified a narrow area around the upper elevational limit of alpine grasslands where the alpine grassline was potentially located. Then, we used linear discriminant analysis to adaptively generate from Landsat reflectance features a synthetic feature that maximized the difference between vegetated and unvegetated pixels in each of these areas. After that, we designed a graph‐cut algorithm to integrate the advantages of the Otsu and Canny approaches, which was used to determine the precise position of the alpine grassline from the synthetic feature image. Validation against alpine grasslines visually interpreted from a large number of high‐spatial‐resolution images showed a high level of accuracy (R2,.99 and.98; mean absolute error, 22.6 and 36.2 m, vs. drone and PlanetScope images, respectively). Across the Tibetan Plateau, the alpine grassline elevation ranged from 4038 to 5380 m (5th–95th percentile), lower in the northeast and southeast and higher in the southwest. This study provides a method for remotely sensing alpine grasslines for the first‐time at large scale and lays a foundation for investigating their responses to climate change. [ABSTRACT FROM AUTHOR]

Mountain lee waves present significant hazards to aviation, often inducing turbulence and aircraft icing. The current study focuses on understanding the potential impact of global climate change on the precursor environments to mountain lee wave cloud episodes over central Iberia. We examine the suitability of several Global Climate Models (GCMs) from CMIP6 in predicting these environments using the ERA5 reanalysis as a benchmark for performance. The dataset is divided into two periods: historical data (2001–2014) and projections for the SSP5–8.5 future climate scenario (2015–2100). The variations and trends in precursor environments between historical data and future climate scenarios are exposed, with a particular focus on the expansion of the Azores High towards the Iberian Peninsula, resulting in increased zonal winds throughout the Iberian Peninsula in the future. However, the increase in zonal wind is insufficient to modify the wind pattern, so future mountain lee wave cloud events will not vary significantly. The relative humidity trends reveal no significant changes. Moreover, the risk of icing precursor environments connected with mountain lee wave clouds is expected to decrease in the future, due to rising temperatures. Our results highlight that the EC-EARTH3 GCM reveals the closest alignment with ERA5 data, and statistically significant differences between the historical and future climate scenario periods are presented, making EC-EARTH3 a robust candidate for conducting future studies on the precursor environments to mountain lee wave cloud events. [ABSTRACT FROM AUTHOR]

Background: The alpine meadow is one of the most important ecosystems in the Qinghai-Tibet Plateau (QTP), and critically sensitive to climate change and human activities. Thus, it is crucial to precisely reveal the current state and predict future trends in the carbon budget of the alpine meadow ecosystem. The objective of this study was to explore the applicability of the Biome-BGC model (BBGC) in the Qinghai Lake Basin (QLB), identify the key parameters affecting the variation of net ecosystem exchange (NEE), and further predict the future trends in carbon budget in the QLB. Results: The alpine meadow mainly acted as carbon sink during the growing season. For the eco-physiological factors, the YEL (Yearday to end litterfall), YSNG (Yearday to start new growth), CLEC (Canopy light extinction coefficient), FRC:LC (New fine root C: new leaf C), SLA (Canopy average specific leaf area), C:Nleaf (C:N of leaves), and FLNR (Fraction of leaf N in Rubisco) were confirmed to be the top seven parameters affecting carbon budget of the alpine meadow. For the meteorological factors, the sensitivity of NEE to precipitation was greater than that to vapor pressure deficit (VPD), and it was greater to radiation than to air temperature. Moreover, the combined effect of two different meteorological factors on NEE was higher than the individual effect of each one. In the future, warming and wetting would enhance the carbon sink capacity of the alpine meadow during the growing season, but extreme warming (over 3.84 ℃) would reduce NEE (about 2.9%) in the SSP5-8.5 scenario. Conclusion: Overall, the alpine meadow ecosystem in the QLB generally performs as a carbon sink at present and in the future. It is of great significance for the achievement of the goal of carbon neutrality and the management of alpine ecosystems. [ABSTRACT FROM AUTHOR]

Morocco is located in a region vulnerable to the impacts of climate change, which can have profound effects on its social, economic and environmental systems. This makes studies aimed at forecasting these impacts in future using climate models particularly important. However, the generally coarse spatial resolution of models, combined with a large number of models, imposes a limitation on the models, allowing the selection of the most appropriate ones for climate change impact assessments in a specific region. In this study, 38 GCMs and GCM‐RCMs from CMIP5 ensemble and CORDEX project were downscaled and bias‐corrected for use in projecting climate change over Morocco under the RCP4.5 and RCP8.5 scenarios. A three‐step sequential process was adopted, involving in that order the selection of models based on: (i) projection of climate means; (ii) projection of climate extremes; and (iii) ability of the models to simulate the baseline climate. Climate projections show precipitation decreases of up to 10% by the beginning of the century, with decreases of more than 20% under RCP8.5 projected by 2100, with the central and northern mountainous regions of the country being the most affected. Seasonal projections showed autumn months likely to experience the greatest decline in precipitation, up to 36.56% by the end of the century. Temperature projections revealed an upward trend in mean, maximum and minimum temperatures, with increases of up to 3°C predicted by mid‐century over most of the country, particularly in the winter months. Our results point to a concerning future, with impacts related to decreased precipitation and increased temperatures expected to be many and varied across the country. Nevertheless, they can help provide a knowledge base for efforts to mitigate and adapt to expected changes. [ABSTRACT FROM AUTHOR]

With the EU-funded PACE (Permafrost and Climate in Europe) project at the turn of this century, several deep boreholes (100 m +) were drilled in European mountain sites, including in mainland Norway, Svalbard and Sweden. During other projects from 2004 and the International Polar Year (IPY) period in 2006–2007, several additional boreholes were drilled in different sites in both Norway and Iceland, measuring temperatures along both altitudinal and latitudinal gradients. At most sites, multi-temporal geophysical soundings are available using electrical resistivity tomography (ERT). Here, we study the development of permafrost and ground temperatures in mainland Norway and Iceland based on these data sets. We document that permafrost in Norway and Iceland is warming at a high rate, including the development of taliks in both Norway and Iceland in response to global climate change during the last 20 years. At most sites, ground surface temperature (GST) is apparently increasing more strongly than surface air temperature (SAT). Changing snow conditions appear to be the most important factor for the higher GST rates. Modelling exercises also indicate that the talik development can be explained by both higher air temperatures and increasing snow depth. [ABSTRACT FROM AUTHOR]

Strains of Bacillus genus were isolated from soil samples in the permafrost region (Yakutia, Russia). The phenotypic characteristics of the strains are given. The analysis of the obtained data made it possible to assign them to the Bacillus cereus complex. PCR analysis made it possible to determine the profile of B. cereus toxin synthesis genes in the genomes of the studied strains. Genetic characterization was obtained by RAPD genotyping and using MLVA loci used for genotyping of the anthrax pathogen. The results of genotyping at different levels of resolution made it possible to differentiate the studied strains from the B. anthracis species and to show their intraspecific genetic differences and the degree of relationship. Whole genome sequencing was carried out, based on the data of which MLST genotyping was carried out, which revealed two known sequence types and one new one that is described for the first time in this work. The results we obtained are of practical importance and are extremely interesting from the point of view of the evolution and phylogeography of the B. cereus group, since the fact that strains were isolated from permafrost suggests that their age may be much older than expected. [ABSTRACT FROM AUTHOR]

Soil temperature and moisture are important regulators of a broad range of biotic and abiotic processes in terrestrial ecosystems. Vegetation can, in turn, play a role in regulating soil microclimate, which creates potential for powerful and interactive feedbacks from soil and vegetation on the atmosphere. Although the regulatory effect of vegetation on soil microclimatic conditions has been quite extensively and empirically assessed, most studies have determined the net effect of intact woody vegetation versus bare ground. However, for other plant functional groups we lack a clear understanding of their role and any climate‐context dependency in controlling microclimatic conditions. We investigated the role of three major plant functional groups – graminoids, forbs and bryophytes – in regulating soil microclimate in semi‐natural alpine grasslands. Using a fully factorial above‐ground biomass removal experiment, we assessed the role of these plant functional groups in regulating soil temperature amplitude, soil moisture, and number of freezing days. The experiment was replicated across orthogonal temperature and precipitation gradients in Norway to assess whether the effects of functional group abundance varied with climate. The effect of plant biomass on soil microclimate varied among functional groups across the climatic gradients. Bryophytes reduced growing season soil temperature, whereas graminoids and forbs did not (0.5ºC compared to 0ºC), and with a stronger effect in colder climates at higher elevations and on days with high solar radiation. Bryophyte biomass further reduced the number of soil freezing days at boreal and sub‐alpine sites. Finally, graminoid biomass partly explained variation in soil moisture: soils dried more under graminoids at drier sites. Our findings highlight that functional group identity plays a key role in regulating soil microclimate in alpine grasslands across seasons. The strong effect of bryophytes on soil temperature points to their importance in the plant community for a variety of ecosystem functions, some of which may be indirectly vulnerable to future warming via biomass reductions of bryophytes. [ABSTRACT FROM AUTHOR]

Aim: Alpine treeline ecotones are influenced by environmental drivers and are anticipated to shift their locations in response to changing climate. Our goal was to determine the extent of recent climate‐induced treeline advance in the northeastern United States, and we hypothesized that treelines have advanced upslope in complex ways depending on treeline structure and environmental conditions. Location: White Mountain National Forest (New Hampshire) and Baxter State Park (Maine), USA. Taxon: High‐elevation tree species—Abies balsamea, Picea mariana and Betula cordata. Methods: We compared current and historical high‐resolution aerial imagery to quantify the advance of treelines over the last four decades, and link treeline changes to treeline form (demography) and environmental drivers. Spatial analyses of the aerial images were coupled with ground surveys of forest vegetation and topographical features to ground‐truth treeline classification and provide information on treeline demography and additional potential drivers of treeline locations. We used multiple linear regression models to examine the importance of both topographic and climatic variables on treeline advance. Results: Regional treelines have significantly shifted upslope over the past several decades (on average by 3 m/decade). Gradual diffuse treelines (characterized by declining tree density) showed significantly greater upslope shifts (5 m/decade) compared to other treeline forms, suggesting that both climate warming and treeline demography are important correlates of treeline shifts. Topographical features (slope, aspect) as well as climate (accumulated growing degree days, AGDD) explained significant variation in the magnitude of treeline advance (R2 = 0.32). Main Conclusions: The observed advance of treelines is consistent with the hypothesis that climate warming induces upslope treeline shifts. Overall, our findings suggest that gradual diffuse treelines at high elevations may be indicative of climate warming more than other alpine treeline ecotones and thus they can inform us about past and ongoing climatic changes. [ABSTRACT FROM AUTHOR]

Restoring degraded forest ecosystems is an important element in the ongoing challenge to sustain the integrity and functioning of the biosphere. However, the evaluation of restoration success is hampered by long lead times of management measures in forests. Moreover, forest change is accelerating also in the absence of management because of ongoing climate change. Yet, because a counterfactual is frequently missing, it remains unclear whether restoration measures are aided or impeded by climate change.Here, we analysed the pace and success of forest restoration under climate change, combining field data and simulation modelling. We focused on the management zone of Berchtesgaden National Park (BGNP), Germany, where restoration aims to restore homogeneous Norway spruce (Picea abies) forests to structurally diverse mixed mountain forests. We evaluated three alternative restoration strategies: Two active strategies focused on planting the currently underrepresented silver fir (Abies alba) and European beech (Fagus sylvatica) but differing in the creation of gap‐cuts, and a third passive restoration strategy without interventions. Strategies were simulated with the forest landscape model iLand from 2020 to 2100 under different climate scenarios (historic, RCP 2.6, 4.5, and 8.5).The forests of BGNP developed into structurally diverse and mixed forests under all evaluated management strategies, and differences between active and passive restoration were generally small. While restoration goals for forest structure were largely met by 2100, forest composition remained far from target in all strategies. Climate change aided restoration by significantly increasing the prevalence of silver fir and European beech (+104.2% to +258.6%). Field data on short‐term restoration effects were in line with simulated long‐term trajectories.Synthesis and applications: We here show that forest restoration efforts in Central European mountain forests will likely be accelerated by climate change. Nonetheless, the slow pace of restoration underscores the need for taking action. Our study highlights that active restoration measures such as tree planting can bring the system closer to restoration targets. However, it also demonstrates that passive restoration (no intervention) is a viable option for management, highlighting the need to evaluate restoration measures against the counterfactual of a no intervention strategy. [ABSTRACT FROM AUTHOR]

High mountains are climate change hotspots. Quickly rising temperatures trigger vegetation shifts such as upslope migration, possibly threatening mountain biodiversity. At the same time, mountain slopes are becoming increasingly unstable due to degrading permafrost and changing rain and snowfall regimes, which favour slope movements such as rockfall and debris flows. Slope movements can limit plant colonization, while, at the same time, plant colonization can stabilize moving slopes. Thus, we here propose that response of high mountain environments to climate change depends on a 'biogeomorphic balance' between slope movement intensity and the trait-dependent ability of mountain plants to survive and stabilize slopes. We envision three possible scenarios of biogeomorphic balance: (1) Intensifying slope movements limit vegetation shifts and thus amplify instability. (2) Shifting ecosystem engineer species reduce slope movement and facilitate shifts for less movement-adapted species. (3) Trees and tall shrubs shifting on stable slopes limit slope instability but decrease biodiversity. Previous geomorphic, ecological and palaeoecological studies support all three scenarios. Given differences in ecologic and geomorphic response rates to climate change, as well as high environmental heterogeneity and elevational gradients in mountain environments, we posit that future biogeomorphic balances will be variable and heterogeneous in time and space. To further unravel future biogeomorphic balances, we propose three new research directions for joint research of mountain geomorphologists and ecologists, using advancing field measurement, remote sensing and modelling techniques. Recognizing high mountains as 'biogeomorphic ecosystems' will help to better safeguard mountain infrastructure, lives and livelihoods of millions of people around the world. [ABSTRACT FROM AUTHOR]

Very high tropical alpine ice cores provide a distinct paleoclimate record for climate changes in the middle and upper troposphere. However, the climatic interpretation of a key proxy, the stablewater oxygen isotopic ratio in ice cores (d18Oice), remains an outstanding problem. Here, combining proxy records with climate models, modern satellite measurements, and radiative-convective equilibrium theory, we show that the tropical d18Oice is an indicator of the temperature of the middle and upper troposphere, with a glacial cooling of -7.35° ± 1.1°C (66% CI). Moreover, it severs as a "Goldilocks-type" indicator of global mean surface temperature change, providing the first estimate of glacial stage cooling that is independent of marine proxies as -5.9° ± 1.2°C. Combined with all estimations available gives the maximum likelihood estimate of glacial cooling as -5.85° ± 0.51°C. [ABSTRACT FROM AUTHOR]

Data from existing monitoring schemes point to a global crisis of butterflies across Europe, with habitat loss/degradation, climate change and chemical pollution as the main drivers of decline.The existing butterfly time series from Western Europe come from densely populated, relatively flat areas. However, population trends from less populated areas, such as mountain ranges in the south of Europe, have been less studied, despite these areas harbouring one of the highest butterfly biodiversity of the continent.Here, we analyse trends for butterfly populations in a Southwestern Europe mountain range (Picos de Europa, Northwest Spain), for the last 9 years (2013–2021), across an altitudinal gradient (80–2000 m). We show that this region, protected as National Park more than 100 years ago, is nonetheless under a great threat, with a decline in butterfly abundance of, on average, 5.7% per year (45.7% cumulative decline in the last 9 years).Species at higher elevations are faring worse than those at low elevations and communities at mid‐elevations (below the tree line) are changing towards higher abundance of species with a preference from closed habitats. Combined effects of amplified climate change in mountains and habitat loss, due to abandonment of traditional management, appear to be affecting both individual species and community composition of butterflies in our study area. [ABSTRACT FROM AUTHOR]

Warming in mountain regions is projected to be three times faster than the global average. Pronounced climate change will likely lead to species reshuffling in mountain plant communities and consequently change ecosystem resilience and functioning. Yet, little is known about the role of inter‐ versus intraspecific changes of plant traits and their consequences for functional richness and evenness of mountain plant communities under climate change. We performed a downslope translocation experiment of intact plant‐soil mesocosms from an alpine pasture and a subalpine grassland in the Swiss and Austrian Alps to simulate an abrupt shift in climate and removal of dispersal barriers. Translocated plant communities experienced warmer and dryer climatic conditions. We found a considerable shift from resource conservative to resource acquisitive leaf‐economy in the two climate change scenarios. However, shifts in leaf‐economy were mainly attributable to species turnover, namely colonization by novel lowland species with trait expressions for a wider range of resource use. We also found an increase in vegetative height of the warmed and drought‐affected alpine plant community, while trait plasticity to warming and drought was limited to few graminoid species of the subalpine plant community. Our results highlight the contrast between the strong competitive potential of novel lowland species in quickly occupying available niche space and native species' lack of both the intraspecific trait variability and the plant functional trait expressions needed to increase functional richness under warming and drought. This is particularly important for the trailing range of many mountain species (i.e. subalpine zone) where upward moving lowland species are becoming more abundant and abiotic climate stressors are likely to become more frequent in the near future. Our study emphasizes mountain plant communities' vulnerability to novel climates and biotic interactions under climate change and highlights graminoid species as potential winners of a warmer and dryer future. Keywords: alpine grassland, functional diversity, invasion, species turnover, traitspace, translocation [ABSTRACT FROM AUTHOR]

Latent heat released during orographic precipitation over the Western Ghat (WG) Mountain drives the Indian Summer Monsoon. Instrumental data record a considerable spatiotemporal variation of rainfall amount along the mountain. Although Indian teak (Tectona grandis LF) samples from WG have been used earlier for reconstructing past monsoon rainfall, the effect of rainfall variation on the annual ring growth pattern along the mountain has not been extensively studied yet. To address this issue, tree-ring width data series from three locations—Dahanu (1763 -1985), Nagerhole (1703–2016), and Tekkedy (1785–2003) are presented in this study. The locations are situated along WG from north to south. Monthly mean rainfall data obtained from the nearest observatories show a decreasing (increasing) rainfall amount from north to south during summer monsoon (pre and post-monsoon). We obtain a significant positive correlation between ring width indices and monsoon rainfall and a negative correlation with summer (especially May) temperature suggesting a contrasting response of summer temperature and monsoon rain on teak growth. The correlation between rainfall and ring width varies from southern to northern WG (both in significance level and the number of months with significant correlation). While the southernmost location exhibits positive (significant) correlations for both pre and summer monsoon months, the correlations are found for only two summer monsoonal months in the northernmost location. This spatial correlation trend reflects the variation of the pre-monsoon to monsoon rainfall ratio observed in our study locations. This observation is further substantiated by soil moisture-ring width relationship. Furthermore, our study shows that ring width indices respond to a variation of western equatorial Pacific sea surface temperature and vapor pressure deficit. Our study, therefore, suggests that the Indian teak samples can be used for understanding regional and seasonal scale rainfall/soil moisture variation along the WG and teleconnection studies. [ABSTRACT FROM AUTHOR]

The response of lightning to a changing climate is not fully understood. Historic trends of proxies known for fostering convective environments suggest an increase of lightning over large parts of Europe. Since lightning results from the interaction of processes on many scales, as many of these processes as possible must be considered for a comprehensive answer. Recent achievements of decade-long seamless lightning measurements and hourly reanalyses of atmospheric conditions including cloud micro-physics combined with flexible regression techniques have made a reliable reconstruction of cloud-to-ground lightning down to its seasonally varying diurnal cycle feasible. The European Eastern Alps and their surroundings are chosen as reconstruction region since this domain includes a large variety of land-cover, topographical and atmospheric circulation conditions. The most intense changes over the four decades from 1980 to 2019 occurred over the high Alps where lightning activity doubled in the 2010 s compared to the 1980 s. There, the lightning season reaches a higher maximum and starts one month earlier. Diurnally, the peak is up to 50% stronger with more lightning strikes in the afternoon and evening hours. Signals along the southern and northern alpine rim are similar but weaker whereas the flatlands surrounding the Alps have no significant trend. [ABSTRACT FROM AUTHOR]

The Sierra Nevada and Southern Cascades—California's snowy mountains—are primary freshwater sources and natural reservoirs for the states of California and Nevada. These mountains receive precipitation overwhelmingly from wintertime storms including atmospheric rivers (ARs), much of it falling as snow at the higher elevations. Using a seven-decade record of daily observed temperature and precipitation as well as a snow reanalysis and downscaled climate projections, we documented historical and future changes in snow accumulation and snowlines. In four key subregions of California's snowy mountains, we quantified the progressing contribution of ARs and non-AR storms to the evolving and projected snow accumulation and snowlines (elevation of the snow-to-rain transition), exploring their climatology, variability and trends. Historically, snow makes up roughly a third of the precipitation affecting California's mountains. While ARs make up only a quarter of all precipitating days and, due to their relative warmth, produce snowlines higher than do other storms, they contribute over 40% of the total seasonal snow. Under projected unabated warming, snow accumulation would decline to less than half of historical by the late twenty-first century, with the greatest snow loss at mid elevations (from 1500 to 3300 m by the mountain sub-regions) during fall and spring. Central and Southern Sierra Nevada peaks above 3400 m might see occasionally extreme snow accumulations in January–February resulting entirely from wetter ARs. AR-related snowlines are projected to increase by more than 700 m, compared to about 500 m for other storms. We discuss likely impacts of the changing climate for water resources as well as for winter recreation. [ABSTRACT FROM AUTHOR]

Settlement crises in ancient cultures of Western Asia are commonly thought to be caused by climatic events such as severe droughts. However, the insufficient climate proxy situation in this region challenges the inference of clear relationships between climate and settlement dynamics. We investigate the Holocene climatic changes on the Varamin Plain in the context of the climatic history of Western Central Asia by using a transient comprehensive Earth System Model simulation (8 ka BP to pre-industrial), a high-resolution regional snapshot simulation and a synthesis of pollen-based climate reconstructions. In line with the reconstructions, the models reveal only slightly varying mean climatic conditions on the Varamin Plain but indicate substantial changes in seasonality during the Holocene. Increased precipitation during spring, combined with lower temperature and potentially stronger snow accumulation on the upstream Alborz mountains may have led to an increased water supply on the alluvial fan during the vegetation period and thus to more favourable conditions for agricultural production during the Mid-Holocene compared to modern times. According to the model, dry periods on the Central Iranian Plateau are related to particularly weak Westerly winds, fostering the subsidence in the mid-troposphere and hampering precipitation over the region. The model reveals that dry periods have spatially heterogenous manifestations, thus explaining why they do not appear in all proxy records in the wider study region. In fact, the climatic signal may depend on local environmental conditions. The interaction of the topography with the atmospheric circulation leads to additional spatial heterogeneity. Although our results provide several indications for a connection between climate and settlement dynamics, the small overall changes in moisture call into question whether climate is the main driver for settlement discontinuities on the Central Iranian Plateau. To shed further light on this issue, more high-resolution long-term proxy records are needed. [ABSTRACT FROM AUTHOR]

Climate change has a strong impact on the environment in mountain areas, where ecosystems have adapted to climatic conditions that change with elevation. In this study, the response of temperature and precipitation climatic indices in the complex orography setting of the Great Alpine Region is discussed. The high‐resolution gridded dataset that is presented has been produced with the Weather Research Forecasting (WRF) convection permitting regional model. Two 30‐year periods have been considered (1979–2008, 2039–2068), obtained by downscaling global climate simulations with historical setting and RCP8.5 emission scenario. Both daily temperature and precipitation statistics have been found to be significantly different in the two periods, consisting in an overall projected warming and drying of the region. The dependence of the projected changes on elevation is highlighted, indicating a larger warming at medium and high elevations as well as a limited or nonexisting drying at high elevations. Physical mechanisms at the base of those differences are presented and discussed. [ABSTRACT FROM AUTHOR]

Tree line areas exhibited significant changes in response to climate change, including upward migration. Lower tree line dynamics are rarely studied, but as unique features in arid and semi-arid areas, they may influence forest distribution. Here, eight lower tree line plots in a Picea crassifolia Kom. (Qinghai spruce) forest in the arid and semi-arid Qilian Mountains of northwestern China were used to determine changes in tree line location and relationships with meteorological factors during 1968–2018. The results showed that the lower tree line descended by an average of 9.82 m during 1968 to 2018, and exhibited almost no change after 2008. The change in the lower tree line was significantly correlated with the annual average temperature (°C) and annual precipitation (mm) and may be affected by human activities. In the past 50 years, the lower tree line in arid areas exhibited a downward trend. Our findings indicate that the movement of the lower tree line is also an important aspect of climatic changes in coniferous forest distribution in arid and semi-arid mountains. [ABSTRACT FROM AUTHOR]

Climate change will impact environments globally. These changes, however, can affect species or regions differently. The upward limitation of high‐mountain species suggests these are especially prone to the effects of climate change. We assess the impact of future climate scenarios on high‐mountain species' suitable climatic niches. We gathered 1351 occurrence records of high‐mountain (>2000 m asl) squamates and assessed species distribution models for those species occupying more than 10 unique grid‐cells. Afterwards, for each species we ensemble climatic‐niche suitability models for historic (1981–2010) and future climate scenarios (2011–2040, 2041–2070, 2071–2100) for two representative concentration pathways (RCP 2.6 and 8.5). We identified 252 high‐elevation squamate species that occur in Africa, Asia, North America and South America. When we examined species distribution models for the 17 lizard species occupying more than 10 unique grid‐cells, we found a consistent negative effect of future climate change on suitable climatic‐niche models: we inferred species' climatic‐niche losses for 16 species and species' climatic‐niche gains for 1 species. Regardless of future scenarios, two species of lizards will likely lose at least 80% of their suitable climatic niche, and seven species will likely see their suitable climatic niche completely disappear. Climate change will likely have a negative impact on species' suitable climatic‐niche availability. High altitude and associated environmental factors may accelerate local extinctions of mountain reptiles. We highlight the importance of identifying high‐risk species for better conservation efforts. [ABSTRACT FROM AUTHOR]

Root exudation fulfills fundamental roles in regulating carbon (C)-nutrient cycling in forest ecosystems, yet the main ecological drivers of root exudation and underlying mechanisms in forests under natural gradients remain poorly understood. Here, we investigated the intraspecific variation of root exudation rates in two alpine coniferous forests (Abies faxoniana Rehder et Wilson and Abies georgei Orr) along two elevation gradients on the eastern Tibetan Plateau. Meanwhile, the fine root traits and associated climate and soil parameters were assessed to examine the effects of elevation-dependent changes in climatic and soil nutrient conditions on root exudation. Results showed that root exudation rates decreased with increasing elevation and were positively correlated with mean air temperature. However, the relationships of root exudation with soil moisture and soil nitrogen availability were not significant. The structural equation model (SEM) further revealed that air temperature affected root exudation both directly and indirectly through the effects on fine root morphology and biomass, implying that the adaption of root C allocation and fine root morphological traits to low temperatures primarily resulted in declined root exudation at higher elevations. These results highlight the perceived importance of temperature in determining the elevational variation of root exudation in alpine coniferous forests, which has foreseeably great implications for the exudate-mediated ecosystem C and nutrient processes in the face of drastic warming on the eastern Tibetan Plateau. [ABSTRACT FROM AUTHOR]

Aboveground, large and higher trophic‐level organisms often respond more strongly to environmental changes than small and lower trophic‐level organisms. However, whether this trophic or size‐dependent sensitivity also applies to the most abundant animals, microscopic soil‐borne nematodes, remains largely unknown. Here, we sampled an altitudinal transect across the Tibetan Plateau and applied a community‐weighted mean (CWM) approach to test how differences in climatic and edaphic properties affect nematode CWM biomass at the level of community, trophic group and taxon mean biomass within trophic groups. We found that climatic and edaphic properties, particularly soil water‐related properties, positively affected nematode CWM biomass, with no overall impact of altitude on nematode CWM biomass. Higher trophic‐level omnivorous and predatory nematodes responded more strongly to climatic and edaphic properties, particularly to temperature, soil pH, and soil water content than lower trophic‐level bacterivorous and fungivorous nematodes. However, these differences were likely not (only) driven by size, as we did not observe significant interactions between climatic and edaphic properties and mean biomasses within trophic groups. Together, our research implies a stronger, size‐independent trophic sensitivity of higher trophic‐level nematodes compared with lower trophic‐level ones. Therefore, our findings provide new insights into the mechanisms underlying nematode body size structure in alpine grasslands and highlight that traits independent of size need to be found to explain increased sensitivity of higher trophic‐level nematodes to climatic and edaphic properties, which might affect soil functioning. [ABSTRACT FROM AUTHOR]

There are different ideas about the classification and distribution of permafrost in Mongolia. Terms such as continuous, discontinuous, sporadic, and isolated permafrost are inconsistently applied; hence, maps of permafrost display different distribution patterns. Particularly, the southern border of the Siberian permafrost in Mongolia is still debated. Furthermore, comparing these maps is challenging when studying impacts of climate change on permafrost. While, without a doubt, Mongolia's permafrost is in a stage of significant degradation and has receded from vast regions, telling this story is difficult when data are not easily comparable. Today, all permafrost is restricted to Mongolia's mountains. To better describe permafrost that depends on orography and elevation, we propose to use the more appropriate term 'mountain permafrost.' Surprisingly, the term 'periglacial' is mostly absent in the literature on Mongolia's permafrost. We here aim to clarify definitions of terms and hope that future studies will pay attention to both periglacial environments and mountain permafrost. [ABSTRACT FROM AUTHOR]

Aim: Climate change is transforming mountain summit plant communities worldwide, but we know little about such changes in the High Andes. Understanding large‐scale patterns of vegetation changes across the Andes, and the factors driving these changes, is fundamental to predicting the effects of global warming. We assessed trends in vegetation cover, species richness (SR) and community‐level thermal niches (CTN) and tested whether they are explained by summits' climatic conditions and soil temperature trends. Location: High Andes. Time period: Between 2011/2012 and 2017/2019. Major taxa studied: Vascular plants. Methods: Using permanent vegetation plots placed on 45 mountain summits and soil temperature loggers situated along a ~6800 km N‐S gradient, we measured species and their relative percentage cover and estimated CTN in two surveys (intervals between 5 and 8 years). We then estimated the annual rate of changes for the three variables and used generalized linear models to assess their relationship with annual precipitation, the minimum air temperatures of each summit and rates of change in the locally recorded soil temperatures. Results: Over time, there was an average loss of vegetation cover (mean = −0.26%/yr), and a gain in SR across summits (mean = 0.38 species m2/yr), but most summits had significant increases in SR and vegetation cover. Changes in SR were positively related to minimum air temperature and soil temperature rate of change. Most plant communities experienced shifts in their composition by including greater abundances of species with broader thermal niches and higher optima. However, the measured changes in soil temperature did not explain the observed changes in CTN. Main conclusions: High Andean vegetation is changing in cover and SR and is shifting towards species with wider thermal niche breadths. The weak relationship with soil temperature trends could have resulted from the short study period that only marginally captures changes in vegetation through time. [ABSTRACT FROM AUTHOR]

Fully mechanized maize production has been trending in China, and using agricultural machinery to harvest maize grains is the focus of the transformation of maize production methods. Grain moisture content is the main factor affecting mechanical kernel harvesting, which is mainly affected by the agronomic characteristics of maize, ecological meteorological factors at the late growth stage, cultivation and management practice and other factors. Northeast China (NEC) is one of the main maize production regions and is the most sensitive regions to climate change in China. Clarifying the climate suitability and suitable zones for mechanical maize kernel harvesting in NEC under future climate conditions can provide scientific basis for improving the mechanization level of maize production and realizing the fully mechanized maize production in the future. In this study, based on the predicted climate data of 2021−2060 under two greenhouse gas concentration scenarios of RCP4.5 and RCP8.5 (the radiation forcing levels will reach 4.5W·m−2 and 8.5W·m−2 by 2100, which representing medium and high emission scenario, respectively) and the growth period data of spring maize, the northern boundaries of climate suitable zones for mechanical kernel harvesting of currently widely planted 29 middle-late spring maize varieties were determined using the kernel moisture content prediction models, and further the multi-variety based climate suitable zones were analyzed for the future 40 years. The results showed that climate very suitable, suitable, moderately suitable and marginally suitable zones for mechanical kernel harvesting will extend from southwest to northeast in NEC. And among different varieties, the northern boundaries of climate suitable zones fluctuate from the southwest to the southeastern mountainous areas of Jilin province (Changbai, Donggang and Songjiang areas) and the northern high latitude areas of Heilongjiang province. Under RCP4.5 (RCP8.5) climate scenario, the very suitable zones for 50% and 80% of middle-late maturing spring maize varieties located in the southern part of Liaoning province (the western and southern parts of Liaoning province). The northernmost can reach 42.0°N and 41.0°N (42.8°N and 41.9°N) latitude, and the easternmost can reach 123.4°E and 123.3°E (124.5°E and 123.3°E) longitude, respectively. The areas account for 5.9% and 1.8% (11.2% and 5.9%) of the potential growing area of spring maize in NEC, respectively. Suitable zones located in the northern and central parts of Liaoning province (the northern part of Liaoning province and southwestern part of Jilin province), with the northernmost reaching 43.0°N and 42.7°N (44.8°N and 42.9°N) latitude, the easternmost reaching 124.7°E and 124.4°E (124.7°E and 124.5°E) longitude, and the areas accounting for 8.3% and 8.9% (4.7% and 6.6%) of potential growing area of spring maize, respectively. In the future 40 years, compared with the RCP4.5 climate scenario, the middle-late maturing varieties of spring maize under RCP8.5 climate scenario have stronger climatic suitability for mechanical kernel harvesting, but the climate very suitable and suitable zones under the two climate scenarios are both small. The climate suitable zones for mechanical kernel harvesting will differ greatly between varieties, so varieties with short growth periods and fast dehydration rates which are suitable for mechanical kernel harvesting should be selected to improve the quality and efficiency of mechanical kernel harvesting in the future. [ABSTRACT FROM AUTHOR]

We currently lack a predictive understanding of how soil archaeal communities may respond to climate change, particularly in Alpine areas where warming is far exceeding the global average. Here, we characterized the abundance, structure, and function of total (by metagenomics) and active soil archaea (by metatranscriptomics) after 5‐year experimental field warming (+1°C) in Italian Alpine grasslands and snowbeds. Our multi‐omics approach unveiled an increasing abundance of Archaea during warming in snowbeds, which was negatively correlated with the abundance of fungi (by qPCR) and micronutrients (Ca and Mg), but positively correlated with soil water content. In the snowbeds transcripts, warming resulted in the enrichment of abundances of transcription and nucleotide biosynthesis. Our study provides novel insights into possible changes in soil Archaea composition and function in the climate change scenario. [ABSTRACT FROM AUTHOR]

Globally, subalpine and alpine plant communities are receiving increasing attention owing to disproportionately rapid warming at high altitudes, and the resultant habitat shrinkage leaving high-altitude specialists with nowhere to migrate. The Hawaiian subalpine zone (1,700–3,000 m) is an interesting example of this potential phenomenon because of the high endemism. We analyzed plant species richness, cover, and density from 89 plots (1,000 m2) sampled in 2010–2018 across two volcanic mountains, Haleakalā on Maui, and Mauna Loa on Hawai'i. Most of the 139 plant species recorded were non-native (55%), with the remainder endemic (31%) and indigenous (14%). Plot-level richness differed from gamma diversity, with endemic species more abundant than non-native species. Non-native species richness was higher on Haleakalā than Mauna Loa. These communities are patchy with low-lying (<1 m) vegetation, and lower cover on younger drier Mauna Loa (36%) than Haleakalā (54%). Density was largely consistent with the understory cover data, with endemic Vaccinium reticulatum (>3,500/ha) and indigenous Leptecophylla tameiameiae (>2,430/ha) shrubs dominant on both volcanoes. Woodland communities were encountered only on Mauna Loa, with endemic trees Metrosideros polymorpha on wetter, south aspects, and Sophora chrysophylla on the drier, leeward side. Hawaiian subalpine vegetation varies among islands, volcanoes, and aspects, yet remains largely native-dominated, though with increasing threats from climate change, invasive non-native species, and wildfire. We recommend continued monitoring of biotic communities and climate in this sensitive zone, in situ physiological studies for the native matrix species, stricter non-native species biosecurity and sanitation protocols, wildfire prevention, and improved documentation of the effects of feral ungulates. [ABSTRACT FROM AUTHOR]

Between 1958 and 2018, multiple roadside surveys were conducted on the upper altitudinal limits of the alpine Maunaloa (now preferred Hawaiian language spelling of Mauna Loa) vascular flora from near tree line (2,525 m) to the NOAA Mauna Loa Observatory (MLO) at 3,397 m. Five native plant species were encountered in 1958 on numerous sparsely vegetated historic and prehistoric basaltic lava flows. A resurvey of the roadside 50 years later (2008) yielded 22 species including nine new native species and eight aliens. The aliens were limited to a few individuals at sites disturbed by human activity. Here, floristic change along the transect was reassessed after 60 years (2018), recording a total of 30 species with 15 natives and 15 aliens. Floristic diversity and shifts in altitudinal limits are evaluated in relation to well documented and dramatic local climate change over recent decades, along with the competing influences of substrate-control and increasing human disturbance. The results indicate that lava substrate age and textural variation, along with human mediated propagule pressure, and associated disturbance exert greater impact than rapid climate change in explaining current patterns of plant distribution and diversity in this hyper-arid, alpine environment. This long-term monitoring effort of alpine lava flows has also informed and reinforced a more general moisture/substrate-control model for early primary succession extending to lower subalpine mountain elevations involving the two dominant lava flow textural classes: ' a ' ā and pāhoehoe. [ABSTRACT FROM AUTHOR]

As many tree species populations are being degraded by climate change, adaptive conservation, and forest management, such as assisted gene flow (AGF), can provide the genetic variation needed to adapt to climate change. The core of this strategy is to assist the adaptation process in populations at risk of climate maladaptation by introducing individuals with beneficial alleles to cope with expected climate changes. Castanea sativa Mill. (sweet chestnut) is an essential component of natural forests in the Mediterranean and Caucasian regions, with a long history of cultivation. Current climate change may seriously threaten the long-term persistence of the species, particularly in the Caucasus region, where the largest range reductions are predicted. Here, we used Species Distribution Models (SDMs) to assess the feasibility of AGF in European and Caucasian populations of Castanea sativa. Bioclimatic variables for present (1981-2010) and future (2071-2100) conditions were obtained from the CHELSA climate database. The final models of future species ranges were averaged across three climate models (IPSL-CM6A-LR, MPI-ESM1-2-HR and UKESM1-0-L) and three climate change scenarios -- SSP1-2.6, SSP3-7.0 and SSP5-8.5. There are marked differences in the climatic niches of the Iberian, Alpine-Apennine, Balkan, and Caucasian populations, with significant implications for AGF. The most suitable European areas for the Caucasian populations were found only in the Adriatic region. The Iberian populations were not compatible with the predicted future climate in the Caucasus in any of the scenarios tested. Suitable areas for Alpine-Apennine populations within the AGF strategy were predicted in the Colchic lowlands, the eastern Pontic mountains and the Hyrcanian forests in the SSP1-2.6 and SSP3-7.0 climate change scenarios. In contrast, the Balkan populations would be compatible at most with the western Pontic mountains and, to a lesser extent, with the Hyrcanian forests. According to the most damaging climate scenario SSP5-8.5, the potential of AGF in the Caucasus with Alpine-Apennine and Balkan populations could be very limited. Our study showed limited applicability of AGF for Castanea sativa between the European and Caucasian populations due to low climate match. Genomic modelling is needed to fully assess the feasibility of this strategy in the species. [ABSTRACT FROM AUTHOR]

Simple Summary: Tropical mountains are rather interesting ecosystems that exhibit a diverse array of features of an ecological niche that shapes the geographic distribution of species and their co-occurrence patterns. Both historical and contemporary factors significantly influence species and lineages diversification and distribution on mountains. We studied the Peromyscus mexicanus rodent group, distributed across mountains in Guatemala-Chiapas and Central America. We aimed to describe the phylogeography, demography, current distribution, and potential range changes due to future climate change. Based on a framework of genetic (mitochondrial and nuclear sequences) and ecological niche modeling methods, we show that lineages with particular ecological features and distribution on lowlands and highlands have distinctive demographic histories associated with glacial and interglacial cycles during the Pleistocene–Holocene. Additionally, the distribution range of some lineages will potentially be significantly reduced by future climate change. This information is crucial for management and conservation purposes for these lineages in particular, but also as a cautionary tale for potential climate change impacts on a variety of mountain taxa. Mountains harbor a significant number of the World's biodiversity, both on tropical and temperate regions. Notably, one crucial gap in conservation is the consideration of historical and contemporary patterns influencing differential distribution in small mammal mountain species and how climate change will affect their distribution and survival. The mice Peromyscus mexicanus species group is distributed across mountains in Guatemala-Chiapas and Central America, which experienced significant effects of glacial and interglacial cycles. We determined phylogeographic and demographic patterns of lowlands and highlands mountain lineages, revealing that the radiation of modern P. mexicanus lineages occurred during the Pleistocene (ca. 2.6 mya) along Nuclear Central America. In concert with climatic cycles and the distribution of habitats, lowland and highland lineages showed recent population size increase and decrease, respectively. We also estimated the current and future distribution ranges for six lineages, finding marked area size increase for two lineages for which vegetation type and distribution would facilitate migrating towards higher elevations. Contrastingly, three lineages showed range size decrease; their ecological requirements make them highly susceptible to future habitat loss. Our findings are clear evidence of the negative impacts of future climate change, while our ability to manage and conserve these vulnerable ecosystems and mountain species is contingent on our understanding of the implications of climate change on the distribution, ecology, and genetics of wildlife populations. [ABSTRACT FROM AUTHOR]

Pollen-based vegetation, biodiversity, and biome reconstructions over the last 15,500 years from sediment core data at Mbi Crater in the Cameroon highlands (6.089273° N, 10.348549° E; 2015 m above sea level) are used to discuss the behavior of the lower edge of the Afromontane forest facing climate change. The data reveal that the post-glacial forest change gradually happened at Mbi and that the forest-wooded grassland ecotone was highly influenced by the climate variability related to the North Atlantic. The forest disruption and diversity loss intermittently occurred over the whole period, and their vegetation changes temporally match dry-cold events at the northern latitudes during the Younger Dryas, at 9.5–9.1 ka, 8.6–8.0 ka, 6.7–6.0 ka, 3.2 ka, and during the Little Ice Age (LIA). During the LIA, the mountain forest was subject to unprecedented levels of disturbance at all altitudes, unlike the seasonal lowland forests, which appears to have been only marginally affected. [ABSTRACT FROM AUTHOR]

We present the results of a study of the Lepidoptera species inhabiting the various biotic zones of the western slope of the Sierra Nevada Mountains, from the Great Central Valley to the mountain crest, in an area around an approximate transect from the city of Fresno to Mono Pass. The investigation methods included day-catching, day- and nocturnal trapping, searching and rearing of immature stages, and catch and release techniques. We identified 1092 species. Most of them represented Noctuoidea, Geometroidea, Gelechioidea, Pyraloidea, and Tortricoidea superfamilies. Most species were encountered at the base of the mountain, in the Foothill Woodland zone, indicating a low-plateau pattern of species richness for our sampled area. We found a bimodal annual species richness curve at the lower elevations (Valley Floor and Foothill Woodland) with a peak in May/June and another one in October. At higher altitudes there was only one richness peak, in July. In the Valley Floor and Foothill Woodland zones there was continuous flight activity throughout the year, while at higher altitudes this activity became gradually restricted to the warmer periods of the year. Anthropogenic changes were detected in the natural habitat at all elevations. These were most pronounced in the Valley Floor and Foothill Woodland zones, thereafter decreasing with the altitude. We found a direct relationship between the mean low temperature values in any given zone and month and the number of species flying at that time and altitude. We assessed this relationship visually, from the charts we plotted for each zone with the pertinent values. During this study, we encountered larval-host plant associations for Udea vacunalis (Pyralidae), Anoncia mosa (Cosmopterygidae), and Aristotelia sp. (Gelechiidae) for which we could not find any references in the literature as well as certain larval habits of Plebejus acmon and Agriades podarce (both Lycaenidae) that expand the awareness concerning their larval behaviors. [ABSTRACT FROM AUTHOR]

Social-ecological systems in mountains are sensitive to the effects of climate change and are being affected at rates faster than other terrestrial habitats. We need to know which species are likely to be "winners" and which are likely to be "losers" in the context of climate change. This study evaluated the current and predicted future habitat suitability of selected range-expanding woody plant species (Acacia dealbata, Leucosidea sericea, Vernonanthura phosphorica) in African mountains under climate change. These species are representative of range-expanding plants, which have the potential to affect ecosystem services. Future average temperature is projected to decline in African mountains whereas global mean temperatures are projected to increase. Climate-change models may not be capturing dynamics in the climate of African mountains, possibly due to a lack of representative climate data used in calibrating these models. Although only climate variables were assessed, potential species distribution results were considered accurate according to model evaluation metrics, and some static factors thought to influence species distribution were strongly coupled to climate. Vernonanthura phosphorica and A. dealbata are likely to spread under climate change. The extent of habitat suitable for L. sericea is predicted to decline under climate change. An improved understanding of climate change in mountain systems through better representation of mountain climates in climate-change models could enhance the accuracy of species distribution models. [ABSTRACT FROM AUTHOR]

Plot-based monitoring has yielded much information on the taxonomic diversity and carbon (C) storage in tropical lowland forests of the Amazon basin. This has resulted in an improved understanding of the relationship between lowland forest biomass dynamics and global change drivers, such as climate change and atmospheric CO2 concentration. Much less attention has been paid to the mountain ecosystems of South America that comprise montane forests and alpine vegetation (páramo, puna, high Andean grasslands, wetlands, and alpine heath). This vegetation complex provides a variety of ecosystem services and forms a natural laboratory along various physiographic, geological and evolutionary history/biogeography, and land use history gradients. Here, we review existing empirical understanding and model-based approaches to quantify the contribution of mountain ecosystems to ecosystem service provision in the rapidly changing socioecological setting of the South American mountains. The objective of this paper is to outline a broad road map for the implementation of mountain vegetation into dynamic global vegetation models (DGVM) for use in Earth System Models (ESM), based on our current understanding of their structure and function and of their responsiveness to global change drivers. We also identify treeline processes, critical in mountain ecosystems, as key missing elements in DGVMs/ESMs, and thus explore in addition a treeline model. Stocktaking of the availability of empirical data was undertaken from eight research sites along the Andes and in south-eastern Brazil. Out of eight sites, two (one each in Venezuela and Brazil) had some climate, ecological and ecophysiological data potentially suitable to parametrise a DGVM. Tree biomass data were available for six sites. A preliminary assessment of the Joint UK Land Environment Simulator (JULES) DGVM was made to identify gaps in available data and their impacts on model parametrisation and calibration. Additionally, the potential climate-determined elevation of the treeline was modelled to check the DGVM for its ability to identify the transition between the montane forest and alpine vegetation. Outcomes of the evaluation of the JULES land surface model identified the following key processes in montane forests: temperature-related decrease in net primary production, respiration, and allocation to above-ground biomass and increase in soil C stocks with elevation. There was a variable agreement between simulated biomass and those derived from field measurements via allometric equations. We identified major gaps between data availability and the needs for process-based modelling of South American mountain vegetation and its dynamics in DGVMs. To bridge this gap, we propose a transdisciplinary network, composed of members of the theoretical/modelling and empirical scientific communities, to study the natural dynamics of mountain ecosystems and their responses to global change drivers locally, regionally and at the continental scale, within a social-ecological system framework. The work presented here forms the basis for the design of data collection from field measurements and instrumental monitoring stations to parametrise and verify DGVMs. The network is designed to collaborate with and complement existing long-term research initiatives in the region and will adopt existing standard field protocols. Complementary protocols will ensure compatibility between field data collection and data needed for process-based and empirical models. [ABSTRACT FROM AUTHOR]

This research examined how edaphoclimatic variations are related to dendrometric variables of the Tara tree in natural and agroforestry systems in Cajamarca, Peru. Evaluations followed three approaches: (a) principal components analysis (PCA) with environmental factors and altitude classes with 1 °C of temperature variation for edaphic and dendrometric variables; (b) evaluation of possible differences by the bootstrap method for the different variables in the PCAs; and (c) correlation analysis between plant density, plant and crown height, stem and crown diameter, and the number of stem branches with the physical and chemical attributes of the soil and with air temperature. In the altitudinal gradient from 2021 to 3007 ± 7 m, the temperature ranged from 19.8 to 13.4 ± 0.4 °C; the soils possessed alkaline pH, high organic matter (OM), K and CEC, lower contents of CaCO3, N, P, K, B, Cu, Fe, Mn, and Zn. The soil properties with the most significant contribution to PCAs were OM, CEC, N content, and sand, with no variation among environments but among altitudes. None of the dendrometric variables varied as a function of altitude and temperature in PCAs run in the natural environment. However, in the agroforestry environment, there was a greater crown diameter, and tree and crown height in the 2185 m altitude class associated with Medicago sativa. In contrast, the opposite behavior was found in these variables and in the altitude class 2798 m associated with low Fe content, and already in the altitude class at 3007 m, a larger stem diameter is associated with higher levels of CaCO3. The anthropic effect on the agroforestry environment did not significantly alter the soil's CEC, OM, N, and sand. Tara's crown diameter and tree height appeared higher in agroforestry environments. The variations of Fe and CaCO3 in the soil might have influence on the development of Tara individuals in natural and agroforestry environments. It is important to carry out further studies for a better understanding of the relationship between the production of Tara pods and soil fertility in altitudinal variation, aiming to improve the income and employment of family farmers who exploit Tara in the Peruvian Andes. [ABSTRACT FROM AUTHOR]

There is a significant impact of climate change on species distribution and vegetation patterns in high mountain regions, which is a major topic of research in biogeography. It has recently warmed up on the Western Sichuan Plateau, one of the most vulnerable regions to climate change. Based on the MaxEnt model, we were able to predict distributions based on current and future climate conditions, and determine the trend of distribution change and the underlying climate factors. Under current climate conditions, the two typical tree species display distinct spatial distributions. Furthermore, under future climate conditions, distribution ranges of both typical tree species will shrink and move to the northern part of the plateau. The variation in temperature between seasons and years affected the distribution of two tree species. This study provided a scientific basis for understanding how high mountain and plateau forests respond to climate change. [ABSTRACT FROM AUTHOR]