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There are 14 northern communities in Nunavik, the Arctic region of Quebec province, Canada. Transportation infrastructure plays a vital role in the social and economic development of these localities. The thawing of permafrost compromises the stability of northern transportation infrastructure. Harsh Arctic climate conditions limit the installation of effective monitoring systems to assess infrastructure stability. In Akulivik, the access road connects the Akulivik airport and the village of Akulivik. There is no monitoring to observe the thermal condition of the permafrost foundation of the access road, hindering the capacity to perform preventive maintenance activities, especially in the context of observed climate warming in Nunavik. This paper describes a project aiming at the assessment of the stability of the access road using a new approach and proposes adaptation solutions to stabilize the road, based on design tools recently developed. Particular attention was paid to the foundation soil under the side slope where relatively rapid permafrost degradation was occurring due to accumulated snow. The results indicate a positive thermal gradient of 0.29 degrees C/m under the side slope and a near-zero thermal gradient under the centerline. Projected climate warming was also considered to further investigate the thermal condition, providing a safety margin for the design of promising adaptation solutions. These results assist government agencies in evaluating the thermal conditions of underlying permafrost and deploying potential adaptation solutions in Akulivik.

期刊论文 2024-08-01 DOI: 10.1016/j.coldregions.2024.104230 ISSN: 0165-232X

Global warming effects in temperate and polar regions include higher average temperatures and a decrease in snow cover, which together lead to an increase in the number of freeze-thaw cycles (FTC). These changes could affect the fitness of both terrestrial and aquatic species. In this study, we tested how tardigrades, ubiquitous microscopic invertebrates, face FTC. Tardigrades are amongst the most resistant animals to unfavorable conditions, including long and deep freezing periods, and are an emerging model group for invertebrate ecology and evolution. We used 12 populations of tardigrades, representing different families within order Parachela, inhabiting different ecosystems (glaciers, snow, terrestrial, aquatic), found in various substrates (mosses, sediments in lakes, cryoconite on glaciers, and snow), and originating from different latitudes and altitudes. We estimated the number of cycles required to kill 50% of individuals and tested for its association with ecological characteristics of the natural habitat (e.g., number of months with predicted FTC), while accounting for phylogeny. The most resistant tardigrades to FTC were the ones from mountain areas and glaciers. The estimated number of cycles required to kill 50% of individuals was the highest for mountainous species inhabiting rock pools and cryoconite holes on glaciers (30 and 14 FTC, respectively). Tardigrades from lowlands were the most sensitive to changes, with 50% of individuals dying after three FTC, while lacustrine and subtropical tardigrades required only one FTC to reach 50% mortality. Our study shows that the response to recurrent freezing stress is taxon dependent and related to the local environmental conditions. The predicted increase of FTC cycles will negatively impact tardigrade populations. Considering the abundance and various trophic roles of tardigrades, reduction in population sizes or the disappearance of some fragile species could affect the functioning of both aquatic and terrestrial ecosystems. Tardigrades are candidate indicators of how freeze-thaw cycles impact ubiquitous microscopic metazoans with similar physiological capabilities.

期刊论文 2023-10-01 DOI: 10.1016/j.ecolind.2023.110460 ISSN: 1470-160X

Changing climatic conditions in High Mountain Asia (HMA), especially regional warming and changing precipitation patterns, have led to notable effects on mountain permafrost. Comprehensive knowledge of mountain permafrost in HMA is mostly limited to the mountains of the Qinghai-Tibetan Plateau, with a strong cluster of research activity related to critical infrastructure providing a basis for related climate adaptation measures. Insights related to the extent and changing characteristics of permafrost in the Hindu Kush Himalaya (HKH), are much more limited. This study provides the first comprehensive review of peer-reviewed journal articles, focused on hydrological, ecological, and geomorphic impacts associated with thawing permafrost in HMA, as well as those examining adaptations to changes in mountain permafrost. Studies reveal a clear warming trend across the region, likely resulting in increased landslide activity, effects on streamflow, soil saturation and subsequent vegetation change. Adaptation strategies have been documented only around infrastructure megaprojects as well as animal herding in China. While available research provides important insight that can inform planning in the region, we also identify a need for further research in the areas of hazards related to changing permafrost as well as its effect on ecosystems and subsequently livelihoods. We suggest that future planning of infrastructure in HMA can rely on extrapolation of already existing knowledge within the region to reduce risks associated with warming permafrost. We highlight key research gaps as well as specific areas where insights are limited. These are areas where additional support from governments and funders is urgently needed to enhance regional collaboration to sufficiently understand and effectively respond to permafrost change in the HKH region.

期刊论文 2023-09-01 DOI: 10.1088/1748-9326/acf1b4 ISSN: 1748-9326

A clear understanding of the changes of water resources under the background of environmental changes is of great significance for scientific management and utilization of water resources in China. This study systematically analyzed the spatial-temporal variations of surface water resources in China since 2000. Water vulnerability in current (2010s) and its trends from 2000 to late-2010s in different regions of China were also summarized. In addition, the correspondingly adaptive measures to counter regional risks to water resources were proposed. We concluded that the runoff of major rivers had been decreasing in eastern China and increasing in western China during 2000-2018. In the arid area of Northwest China, the alpine runoff has shown an overall upward trend since the late-1990s/early-2000s, with a 10%-25% increase caused by the increase of glacial meltwater and precipitation. While the runoff of each hydrological station in the 2000s-2010s was 34.7% lower than that in the 1950s-2010s on average. The increases in precipitation and glacial meltwater with global warming caused a rapid expansion of lakes in the Qinghai-Tibet Plateau and Xinjiang, thus leading to an increase in total area and water quantity of lakes in China from 1995 to 2015. The mean contribution rates of climate change and human activity to runoff change in river basins of China were 53.5% and 46.5%, respectively, during the period of 2000-2010s. The driving factor of runoff change in many river basins has gradually changed from climate change (1950s-2000) to human activity (2000-2018). During 2000-2018, the contributions of human activities to runoff change were 50%-80% in major rivers of eastern China. The vulnerability in most areas of Northwest China and North China is generally high, with the vulnerability index greater than 0.6. Comparatively, in Northeast, East, South, and Central China, it is lower or not vulnerable. In Southwest China, the vulnerability varies greatly with Yunnan and Sichuan relatively low while Chongqing and Guizhou relatively high. The precipitation increase, the application of water-saving technology, the establishment of flood control and drought relief engineering facilities, and the introduction of relevant policies and measures have helped to gradually reduce the vulnerability of water resources in most areas of North and Northwest China (except Xinjiang) from 2000 to 2010s. Water vulnerability has been increasing in southern China, caused by climate change and the development of industry and agriculture, which increases water resource exposure since 2000. Based on the typical risk factors and vulnerability characteristics of water resources in different regions, this study proposed some targeted adaptive measures correspondingly so as to scientifically deal with the problems of surface water resources in China.

期刊论文 2023-04-01 DOI: http://dx.doi.org/10.1016/j.accre.2020.11.002 ISSN: 1674-9278

The harsh climatic conditions of deserts may lead to unique adaptations of microbes, which could serve as potential sources of new metabolites to cope with environmental stresses. However, the mechanisms governing the environmental adaptability and antimicrobial activity of desert Streptomyces remain inadequate, especially in extreme temperature differences, drought conditions, and strong radiation. Here, we isolated a Streptomyces strain from rocks in the Kumtagh Desert in Northwest China and tested its antibacterial activity, resistance to UV-C irradiation, and tolerance to hydrogen peroxide (H2O2). The whole-genome sequencing was carried out to study the mechanisms underlying physiological characteristics and ecological adaptation from a genomic perspective. This strain has a growth inhibitory effect against a variety of indicator bacteria, and the highest antibacterial activity recorded was against Bacillus cereus. Moreover, strain D23 can withstand UV-C irradiation up to 100 J/m(2) (D10 = 80 J/m(2)) and tolerate stress up to 70 mM H2O2. The genome prediction of strain D23 revealed the mechanisms associated with its adaptation to extreme environmental and stressful conditions. In total, 33 biosynthetic gene clusters (BGCs) were predicted based on anti-SMASH. Gene annotation found that S. huasconensis D23 contains several genes and proteins associated with the biosynthesis of factors required to cope with environmental stress of temperature, UV radiation, and osmotic pressure. The results of this study provide information about the genome and BGCs of the strain S. huasconensis D23. The experimental results combined with the genome sequencing data show that antimicrobial activity and stress resistance of S. huasconensis D23 was due to the rich and diverse secondary metabolite production capacity and the induction of stress-responsive genes. The environmental adaptability and antimicrobial activity information presented here will be valuable for subsequent work regarding the isolation of bioactive compounds and provide insight into the ecological adaptation mechanism of microbes to extreme desert environments.

期刊论文 2022-11-01 DOI: http://dx.doi.org/10.3390/microorganisms10122408

Mountains are highly diverse in areal extent, geological and climatic context, ecosystems and human activity. As such, mountain environments worldwide are particularly sensitive to the effects of anthropogenic climate change (global warming) as a result of their unique heat balance properties and the presence of climatically-sensitive snow, ice, permafrost and ecosystems. Consequently, mountain systems-in particular cryospheric ones-are currently undergoing unprecedented changes in the Anthropocene. This study identifies and discusses four of the major properties of mountains upon which anthropogenic climate change can impact, and indeed is already doing so. These properties are: the changing mountain cryosphere of glaciers and permafrost; mountain hazards and risk; mountain ecosystems and their services; and mountain communities and infrastructure. It is notable that changes in these different mountain properties do not follow a predictable trajectory of evolution in response to anthropogenic climate change. This demonstrates that different elements of mountain systems exhibit different sensitivities to forcing. The interconnections between these different properties highlight that mountains should be considered as integrated biophysical systems, of which human activity is part. Interrelationships between these mountain properties are discussed through a model of mountain socio-biophysical systems, which provides a framework for examining climate impacts and vulnerabilities. Managing the risks associated with ongoing climate change in mountains requires an integrated approach to climate change impacts monitoring and management.

期刊论文 2022-10-24 DOI: 10.7717/peerj.14253 ISSN: 2167-8359

Understanding how microbial communities adapt to environmental stresses is critical for interpreting ecological patterns and microbial diversity. In the case of the Gobi Desert, little is known on the environmental factors that explain hypolithic colonization under quartz stones. By analyzing nine hypolithic communities across an arid gradient and the effects of the season of the year in the Hexi Corridor of this desert, we found a significant decrease in hypolithic colonization rates (from 47.24 to 15.73%) with the increasing drought gradient and found two distinct communities in Hot and Cold samples, which survived or proliferated after a hot or a cold period. While Cold communities showed a greater species diversity and a predominance of Cyanobacteria, Hot communities showed a predominance of members of the Proteobacteria and the Firmicutes. In comparison, Cold communities also possessed stronger functions in the photosynthesis and carbon metabolism. Based on the findings of this study, we proposed that the hypolithic communities of the Hexi Corridor of the Gobi Desert might follow a seasonal developmental cycle in which temperature play an important role. Thus after a critical thermal threshold is crossed, heterotrophic microorganisms predominate in the hot period, while Cyanobacteria predominate in the cold period.

期刊论文 2022-02-15 DOI: http://dx.doi.org/10.1007/s00248-022-02043-3 ISSN: 0095-3628

The Arctic has experienced rapid change associated with warming since the 1970s. The rapid retreat of the terrestrial cryosphere can release a large amount greenhouse gas from the permafrost regions into the air, and the sea ice decline will affect the CO2 and CH4 balance in the ocean. Changes in the Arctic provide feedback mechanisms that can also impinge on the global ocean's thermohaline circulation. During the past years, the overall natural processes in the Arctic have been studied although the magnitude and timing of carbon release from the cryosphere changes require further investigation. However, few studies have been conducted to link the natural and social systems in the Arctic. Scientists and policymakers must consider the coupled Arctic land, ocean, and social systems in their decisions for coping with climate change.

期刊论文 2021-10-01 DOI: http://dx.doi.org/10.1029/2022EF003293

Through advancements in technology humans have cultivated more food, used more fossil fuel reserves, polluted the environment, and caused climate change. This was not the case some few decades ago where indigenous technologies were used in exploiting natural resources. Unfortunately, the effects of climate change on the planet are no more distant reality. The melting of glaciers, rising sea levels, extreme rainfall, and prolonged drought are already being experienced. These have affected water resources, land, and food security across the world. The limits of conventional climate change adaptation and mitigation strategies call for the integration of indigenous knowledge and technologies for tackling climate change issues. This is because of the importance that indigenous knowledge and technologies have for identifying the impacts and as well providing effective adaption and mitigation strategies to climate change. Thus, this chapter explores the potential of indigenous knowledge and technologies for the sustainable management of water, land, and food security amidst climate change. The applications of indigenous technologies and knowledge such as agroforestry, the use of sacred groves to conserve water, land, and biodiversity resources, and the practising of conservation-agriculture are discussed as solutions for reducing greenhouse gas emissions, water shortages, land degradation, and pollution. However, these indigenous technologies will be less useful in today's world if not harnessed. Thus also in this chapter, the scientific know-how available to improve the effectiveness of indigenous technologies for the sustainable use of water, land, and food resources have been identified (Robotics, sensors/detectors, internet of things) and discussed.

期刊论文 2021-08-12 DOI: 10.3389/fsufs.2021.691603

Coastal inundation causes considerable impacts on communities and economies. Sea level rise due to climate change increases the occurrence of coastal flood events, creating more challenges to coastal societies. Here we intend to draw the understanding of coastal inundation from our early studies, and provide a silhouette of our approaches in assessing climate change impacts as well as developing risk-based climate adaptation. As a result, we impart a distinctive view of the adaption towards the integration of asset design, coastal planning and policy development, which reflect multiscale approaches crossing individual systems to regions and then nation. Having the approaches, we also discussed the constraints that would be faced in adaptation implementation. In this regard, we initially follow the risk approach by illustrating hazards, exposure and vulnerability in relation to coastal inundation, and manifest the impact and risk assessment by considering an urban environment pertinent to built, natural, and socioeconomic systems. We then extend the scope and recommend the general approaches in developing adaptation to coastal inundation under climate change towards ameliorating overall risks, practically, by the reduction in exposure and vulnerability in virtue of the integration of design, planning and polices. In more details, a resilience design is introduced, to effectively enhance the capacity of built assets to resist coastal inundation impact. We then emphasize on the cost-effective adaptation for coastal planning, which delineates the problem of under-adaptation that leaves some potential benefits unrealized or over-adaptation that potentially consumes an excessive amount of resources. Finally, we specifically explore the issues in planning and policies in mitigating climate change risks, and put forward some emerging constraints in adaptation implementation. It suggests further requirements of harmonizing while transforming national policies into the contents aligned with provincial and local governments, communities, and households.

期刊论文 2020-12-01 DOI: http://dx.doi.org/10.1016/j.accre.2020.11.010 ISSN: 1674-9278
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