The increase in soil temperature associated with climate change has introduced considerable challenges to crop production.Split nitrogen application(SN)represents a potential strategy for improving crop nitrogen use e...The increase in soil temperature associated with climate change has introduced considerable challenges to crop production.Split nitrogen application(SN)represents a potential strategy for improving crop nitrogen use efficiency and enhancing crop stress resistance.Nevertheless,the precise interaction between soil warming(SW)and SN remains unclear.In order to ascertain the impact of SW on maize growth and whether SN can improve the tolerance of maize to SW,a two-year field experiment was conducted(2022-2023).The aim was to examine the influence of two SW ranges(MT,warming 1.40℃;HT,warming 2.75℃)and two nitrogen application methods(N1,one-time basal application of nitrogen fertilizer;N2,one third of base nitrogen fertilizer+two thirds of jointing stage supplemental nitrogen fertilizer)on maize root growth,photosynthetic characteristics,nitrogen use efficiency,and yield.The results demonstrated that SW impeded root growth and precipitated the premature aging of maize leaves following anthesis,particularly in the HT,which led to a notable reduction in maize yield.In comparison to N1,SN has been shown to increase root length density by 8.54%,root bleeding rate by 8.57%,and enhance root distribution ratio in the middle soil layers(20-60 cm).The interaction between SW and SN had a notable impact on maize growth and yield.The SN improved the absorption and utilization efficiency of nitrogen by promoting root development and downward canopy growth,thus improving the tolerance of maize to SW at the later stage of growth.In particular,the N2HT resulted in a 14.51%increase in the photosynthetic rate,a 18.58%increase in nitrogen absorption efficiency,and a 18.32%increase in maize yield compared with N1HT.It can be posited that the SN represents a viable nitrogen management measure with the potential to enhance maize tolerance to soil high-temperature stress.展开更多
A complex system is inherently high-dimensional.Recent studies indicate that,even without complete knowledge of its evolutionary dynamics,the future behavior of such a system can be predicted using time-series data(da...A complex system is inherently high-dimensional.Recent studies indicate that,even without complete knowledge of its evolutionary dynamics,the future behavior of such a system can be predicted using time-series data(data-driven prediction).This suggests that the essential dynamics of a complex system can be captured through a low-dimensional representation.Virus evolution and climate change are two examples of complex,time-varying systems.In this article,we show that mutations in the spike protein provide valuable data for predicting SARS-CoV-2 variants,forecasting the possible emergence of the new macro-lineage Q in the near future.Our analysis also demonstrates that carbon dioxide concentration is a reliable indicator for predicting the evolution of the climate system,extending global surface air temperature(GSAT)forecasts through 2500.展开更多
Increasing temperatures and severe droughts threaten forest vitality globally.Prediction of forest response to climate change requires knowledge of the spatiotemporal patterns of monthly or seasonal climatic impacts o...Increasing temperatures and severe droughts threaten forest vitality globally.Prediction of forest response to climate change requires knowledge of the spatiotemporal patterns of monthly or seasonal climatic impacts on the growth of tree species,likely driven by local climatic aridity,climate trends,edaphic conditions,and the climatic adaption of tree species.The ability of tree species to cope with changing climate and the effects of environmental variables on growth trends and growth-climate relationships across diverse bioclimatic regions are still poorly understood for many species.This study investigated radial growth trends,interannual growth variability,and growth-climate sensitivity of two dominant tree species,Pinus tabulaeformis(PT)and Pinus sylvestris var.mongolica(PS),across a broad climatic gradient with a variety of soil properties in temperate Northern China.Using a network of 83 tree ring chronologies(54 for PT and 29 for PS)from 1971 to 2010,we documented that both species maintained constant growth trends at wet sites,while both displayed rapid declines at dry sites.We reported the species-specific drivers of spatial heterogeneity in growth trends,interannual growth variability,and growth-climate relationships.Calculated climatic variables and soil properties were identified as the most critical factors affecting the growth trends and growth-climate relationships.However,climatic variables play more essential roles than soil properties in determining the spatial heterogeneity of the growth-climate relationship.Lower clay content and higher soil nutrient regimes can exacerbate the moisture-related susceptibility of tree growth.Our findings highlight that soil properties emerged as important modulating factors to predict the drought vulnerability of forests in addition to climatic variables.Considering the continued climate warmingdrying trend in the future,both pines will face a more severe growth decline and increase in drought vulnerability at drier sites with lower clayed soil or higher nutrient regimes.展开更多
The effects of different warm rolling(WR)reductions on the microstructure and mechanical properties of low-Cr FeCrAl alloys at both room and elevated temperatures were investigated.The study revealed that when the WR ...The effects of different warm rolling(WR)reductions on the microstructure and mechanical properties of low-Cr FeCrAl alloys at both room and elevated temperatures were investigated.The study revealed that when the WR reduction is small,it effectively refines the grains and forms a large number of subgrains in the matrix,while also inducing the dissolution of the Laves phase.This enhances the mechanical properties of FeCrAl alloys primarily through grain refinement and solid solution strengthening.Conversely,with larger WR reductions,the grain refinement effect diminishes,but a significant number of Laves phases form in the matrix,strengthening the alloys primarily through precipitation strengthening.WR exhibited a remarkable enhancing effect on the comprehensive mechanical properties at both room and high temperatures,with a signi-ficant enhancement in ductility at high temperatures.Notably,a 10%WR reduction resulted in the optimal overall mechanical properties at both room and elevated temperatures.展开更多
The Tibetan Plateau(TP),known as the“Third Pole of Earth”,and its ecosystem is quite sensitive to climate change(Yao et al.,2012;Qiu,2008).In recent decades,the main TP has experienced warming and humidification(alt...The Tibetan Plateau(TP),known as the“Third Pole of Earth”,and its ecosystem is quite sensitive to climate change(Yao et al.,2012;Qiu,2008).In recent decades,the main TP has experienced warming and humidification(although there has been a drying trend in the southern region),and researchers anticipate that this change will continue in the future(Jiang et al.,2023;Sun et al.,2020;Chen et al.,2015).展开更多
[Objectives]To improve the thermal insulation performance of solar greenhouses in winter,enhance solar energy utilization efficiency,reduce additional carbon emissions,and lower winter heating costs for greenhouses.[M...[Objectives]To improve the thermal insulation performance of solar greenhouses in winter,enhance solar energy utilization efficiency,reduce additional carbon emissions,and lower winter heating costs for greenhouses.[Methods]An active heat storage and release water bag was added inside the solar greenhouse.Comparative experiments were conducted between the experimental greenhouse K1 equipped with the heat storage water bag and the control greenhouse K2 under different winter night weather conditions.[Results]On sunny days,the maximum temperature difference between K1 and K2 was 2.3℃,and the average temperature during the water bag's heat release period increased by 2.2℃;on cloudy days,the maximum temperature difference was 2.2℃,and the average temperature increased by 2.0℃;on snowy days,the maximum temperature difference was 1.8℃,and the average temperature increased by 1.6℃.Additionally,the heat storage capacities of the water bag on sunny,cloudy,and snowy days were 491.4,453.6,and 365.4 MJ,respectively.The corresponding nighttime heat release amounts were 378,302.4,and 226.8 MJ,respectively.The corresponding heat storage-release efficiencies were 76%,66.2%,and 62%,respectively.The service life of the heat storage water bag can reach 10 years,with an annual operating cost of approximately 2500 yuan.[Conclusions]By comprehensively analyzing the initial costs,operating expenses,and cost savings rate compared to coal burning for current main energy-saving heat storage and warming equipment in solar greenhouses,this study provides reference suggestions for the promotion,application,and selection of winter heat storage and warming equipment for solar greenhouses in different regions.Users can choose to install the equipment based on the performance characteristics of the heat storage water bag and their actual needs.展开更多
Lignocellulosic biomass is one of the viable solutions to alleviate the global warming. However, the limited utilization of biomass majorly focused on cellulose and hemicellulose restricts the economic and environment...Lignocellulosic biomass is one of the viable solutions to alleviate the global warming. However, the limited utilization of biomass majorly focused on cellulose and hemicellulose restricts the economic and environmental feasibilities. To cope with this issue, we proposed an integrated process of co-producing 1,6-hexanediol(1,6-HDO) with tetrahydrofuran and adipic acid from biomass, referred to as Strategy A. To compare the impacts of lignin upgrading and feedstock, Strategy B, which co-produces tetrahydrofuran alone, and Strategy C, which is the traditional route to produce 1,6-HDO from fossil fuels, were used. Heat networks are also designed to reduce operating costs and indirect carbon emissions due to energy consumption, saving 87% and 83% of the heat and cooling requirements, respectively, in Strategy A. The market competitiveness of Strategy A was evaluated by determining the minimum selling price through techno-economic analysis, and sustainability was thoroughly investigated by quantifying the environmental impacts through both midpoint and endpoint life-cycle assessments(LCAs).Strategy A was found to be the most favorable both economically(USRDSCHARDOLLAR3,402/ton) and environmentally(-26.9 kg CO_(2)eq.). This indicates that lignin valorization is not only economically but also environmentally preferred. Finally, changes in economic and environmental feasibilities depending on economic, process, and environmental parameters were investigated using sensitivity and uncertainty analyses. The results of these analyses provide valuable insight into bio-based chemical production.展开更多
Mediterranean forest communities are particularly diverse but at risk due to their sensitivity to global warming.Understanding the long-term vulnerability of Mediterranean vegetation to climate change is crucial for c...Mediterranean forest communities are particularly diverse but at risk due to their sensitivity to global warming.Understanding the long-term vulnerability of Mediterranean vegetation to climate change is crucial for conservation and management purposes.Studies on past changes of forest communities in response to climate change at ecologically meaningful resolutions(i.e.,decadal time scales) are therefore essential,but still very rare.The Holocene thermal maximum(HTM;ca.10,000-5,000 cal years before the present(BP)) may be used to study species and community responses to warmer conditions than during recent decades.We performed highresolution multiproxy palaeoecological analyses on sediments from crater Lake Mezzano in central Italy to reconstruct vegetation,diversity,and fire dynamics between 8,450 and 7,050 cal years BP.Ordination,crosscorrelation,and species-response analyses were used to investigate the response of Mediterranean forest communities to HTM climate warming,human impact,and fire.Vegetational changes prior to 7,450 cal years BP were driven by climate.Fagus sylvatica spread into mixed deciduous oak forests during the Early Holocene in response to declining seasonality(cooler summers and warmer winters).Subsequently,Fagus sylvatica declined and evergreen Quercus ilex expanded after 8,200 cal years BP when the climate became warmer.Although reduced,Fagus sylvatica remained important together with deciduous oaks.The co-existence of Fagus sylvatica and evergreen Quercus forests is extremely rare today.Human impact significantly affected forest vegetation after7,450 cal years BP,when Neolithic agricultural activities became important,ultimately extirpating these special communities but fostering the overall biodiversity.However,their past occurrence in several central Italian calderas during the HTM suggests that these environments provided habitats that permitted the thriving of cooltemperate forests of Fagus sylvatica under mesomediterranean conditions,with summers ca.1-2℃ warmer than today.Cool and moist calderas may thus become increasingly important for maintaining Mediterranean mesophilous forest species under global warming conditions.展开更多
Emphasis on future environmental changes grows due to climate change,with simulations predicting rising river temperatures globally.For Poland,which has a long history of thermal studies of rivers,such an approach has...Emphasis on future environmental changes grows due to climate change,with simulations predicting rising river temperatures globally.For Poland,which has a long history of thermal studies of rivers,such an approach has not been implemented to date.This study used 9 Global Climate Models and tested three machine-learning techniques to predict river temperature changes.Random Forest performed best,with R^(2)=0.88 and lowest error(RMSE:2.25,MAE:1.72).The range of future water temperature changes by the end of the 21st century was based on the Shared Socioeconomic Pathway scenarios SSP2-4.5 and SSP5-8.5.It was determined that by the end of the 21st century,the average temperature will increase by 2.1°C(SSP2-4.5)and 3.7°C(SSP5-8.5).A more detailed analysis,divided by two major basins Vistula and Odra,covered about 90%of Poland's territory.The average temperature increase,according to scenarios SSP2-4.5 and SSP5-8.5 for the Odra basin rivers,is 1.6°C and 3.2°C and for the Vistula basin rivers 2.3°C and 3.8°C,respectively.The Vistula basin's higher warming is due to less groundwater input and continental climate influence.These findings provide a crucial basis for water management to mitigate warming effects in Poland.展开更多
The acclimation capacity of Betula pendula and Betula pubescens was studied over 4 years in common gardens in central Italy(43°N)and southern(61°N)and northern Finland(67°N),representing drastically dif...The acclimation capacity of Betula pendula and Betula pubescens was studied over 4 years in common gardens in central Italy(43°N)and southern(61°N)and northern Finland(67°N),representing drastically different photoperiod and climate in temperate,boreal and subarctic vegetation zones.Two study sites that differed in soil fertility were established at each location,giving a total of six common gardens.The birch material was micropropagated from naturally regenerated stands of B.pendula and B.pubescens from Susa Valley and Rochemolle Valley in northern Italy,Punkaharju in southern Finland and Kittilä in northern Finland.The plants were measured for height growth,stem diameter,leaf chlorophyll content,leaf herbivory and pathogen damage.The effects of soil fertility on the common garden results were also analyzed.The results showed high acclimation capacity of B.pendula and B.pubescens after a long-range transfer from southern to northern Europe,despite the major shift in climate and photoperiod.First-year growth on average was best in boreal southern Finland for all origins.Betula pendula grew more than B.pubescens in Italy and southern Finland,while B.pubescens grew more in northern Finland and better tolerated the northward transfer.The height growth of origins showed a clear latitude gradient from slowly growing northern to fast growing southern origins in the nursery and laboratory,but not in the field.Soil fertility explained a significant part of variation among locations not only for growth variables,but also for leaf chlorophyll content and leaf herbivory and pathogen damage.Leaf herbivore and pathogen damage was greatest in southern Finland.Our results demonstrate good survival of birch from northern Italy in Finnish conditions and support the possibility of long-range south-to-north transfer of Betula species to provide resistant planting material in boreal forests for the rapidly changing climate.展开更多
Accurate quantification of life-cycle greenhouse gas(GHG)footprints(GHG_(fp))for a crop cultivation system is urgently needed to address the conflict between food security and global warming mitigation.In this study,t...Accurate quantification of life-cycle greenhouse gas(GHG)footprints(GHG_(fp))for a crop cultivation system is urgently needed to address the conflict between food security and global warming mitigation.In this study,the hydrobiogeochemical model,CNMM-DNDC,was validated with in situ observations from maize-based cultivation systems at the sites of Yongji(YJ,China),Yanting(YT,China),and Madeya(MA,Kenya),subject to temperate,subtropical,and tropical climates,respectively,and updated to enable life-cycle GHG_(fp)estimation.The model validation provided satisfactory simulations on multiple soil variables,crop growth,and emissions of GHGs and reactive nitrogen gases.The locally conventional management practices resulted in GHG_(fp)values of 0.35(0.09–0.53 at the 95%confidence interval),0.21(0.01–0.73),0.46(0.27–0.60),and 0.54(0.21–0.77)kg CO_(2)e kg~(-1)d.m.(d.m.for dry matter in short)for maize–wheat rotation at YJ and YT,and for maize–maize and maize–Tephrosia rotations at MA,respectively.YT's smallest GHG_(fp)was attributed to its lower off-farm GHG emissions than YJ,though the soil organic carbon(SOC)storage and maize yield were slightly lower than those of YJ.MA's highest SOC loss and low yield in shifting cultivation for maize–Tephrosia rotation contributed to its highest GHG_(fp).Management practices of maize cultivation at these sites could be optimized by combination of synthetic and organic fertilizer(s)while incorporating 50%–100%crop residues.Further evaluation of the updated CNMM-DNDC is needed for different crops at site and regional scales to confirm its worldwide applicability in quantifying GHG_(fp)and optimizing management practices for achieving multiple sustainability goals.展开更多
The Taklimakan Desert,located in the heart of central Asia,covers approximately 330000 km^(2),making it China's largest desert and the world's second-largest shifting desert(Dong et al.,2024).With an average a...The Taklimakan Desert,located in the heart of central Asia,covers approximately 330000 km^(2),making it China's largest desert and the world's second-largest shifting desert(Dong et al.,2024).With an average annual precipitation of less than 100 mm and evaporation rates ranging from 2000 to 3000 mm(Yang et al.,2020),it is recognized as one of the driest regions on Earth,often referred to as the“sea of death”.展开更多
Extensive flooding swept across large areas of Central Asia,mainly over Kazakhstan and southwestern Russia,from late March to April 2024.It was reported to be the worst flooding in the area in the past 70 years and ca...Extensive flooding swept across large areas of Central Asia,mainly over Kazakhstan and southwestern Russia,from late March to April 2024.It was reported to be the worst flooding in the area in the past 70 years and caused widespread devastation to society and infrastructure.However,the drivers of this record-breaking flood remain unexplored.Here,we show that the record-breaking floods were contributed by both long-term climate warming and interannual variability,with multiple climatic drivers at play across the synoptic to seasonal timescales.First,the heavy snowmelt in March 2024 was associated with above-normal preceding winter snow accumulation.Second,extreme rainfall was at a record-high during March 2024,in line with its increasing trend under climate warming.Third,the snowmelt and extreme rainfall in March were compounded by record-high soil moisture conditions in the preceding winter,which was a result of interannual variability and related to excessive winter rainfall over Central Asia.As climate warming continues,the interplay between the increasing trend of extreme rainfall,interannual variations in soil moisture pre-conditions,as well as shifting timing and magnitudes of spring snowmelt,will further increase and complicate spring flooding risks.This is a growing and widespread challenge for the mid-to high-latitude regions.展开更多
Agroforestry systems,as composite ecosystems,possess dual characteristics of both forest and agricultural ecosystems.They have been widely recognized as an important land-use approach in agriculture and play a signifi...Agroforestry systems,as composite ecosystems,possess dual characteristics of both forest and agricultural ecosystems.They have been widely recognized as an important land-use approach in agriculture and play a significant role in changing the climate.However,they also face limitations,including uncertainties related to future global climate change,land use,and land cover.This paper summarized the important role of agroforestry systems in the global carbon cycle and carbon balance from the methods and means used in the research on carbon storage and carbon balance and the research status of carbon storage and carbon balance in agroforestry ecosystems at home and abroad,and pointed out the problems that need to be paid attention to in future research.展开更多
Global warming leads to snow cover loss in the alpine ecosystem,exposing seeds to extreme diurnal temperature fluctuations during the growing season.The risk of freezing increases as seeds have increased moisture cont...Global warming leads to snow cover loss in the alpine ecosystem,exposing seeds to extreme diurnal temperature fluctuations during the growing season.The risk of freezing increases as seeds have increased moisture content.Studying the survival mechanisms of seeds at low temperatures can help analyze changes in alpine meadow populations and target conservation efforts.Here,we used three species of Poaceae as a model to understand freezing stress.Fully imbibed Elymus dahuricus,Festuca elata,and Lolium multiflorum seeds were subjected to programmed cooling at fast and slow rates(-1.0/0.05℃/min)and then assessed for survival.Differential Scanning Calorimetry was used to analyze thermal transitions during cooling.HE-stained paraffin sections and a Transmission Electron Microscope were employed to observe internal morphology and ultrastructural changes.E.dahuricus seeds exhibited greater tolerance to low temperatures than those of the other two species,with an LT_(50)of approximately-20℃for both cooling rates and maintained relatively intact ultrastructure.The observed the low-temperature exotherm(LTE)correlated with seed survival,with viability decreasing extensively below LTE.Fast cooling caused fewer changes to seed morphology and ultrastructure than slow cooling,suggesting that the primary survival mechanism during fast cooling is freezing avoidance through supercooling.Seeds exhibited greater freeze tolerance under slow than fast cooling,primarily by migrating intracellular water to extracellular spaces where it froze,causing considerable damage to cell ultrastructure and forming apparent cavities in some seeds.展开更多
Background:There is a gap in understanding the effects of different acupoints and treatment methods(acupuncture and moxibustion)on microcirculatory changes in the lumbar region.Objective:This study aimed to assess the...Background:There is a gap in understanding the effects of different acupoints and treatment methods(acupuncture and moxibustion)on microcirculatory changes in the lumbar region.Objective:This study aimed to assess the thermal effects of acupuncture at Weizhong(BL40),with acupuncture at Chize(LU5)and moxibustion at both acupoints as control interventions.Design,setting,participants and interventions:In this randomized controlled trial,140 healthy participants were equally divided into four groups:acupuncture at BL40(Acu-BL40),acupuncture at LU5(Acu-LU5),moxibustion at BL40(Mox-BL40)and moxibustion at LU5(Mox-LU5).Participants underwent a 30-minute session of their assigned treatment.Infrared thermal imaging was used to collect temperature data on the areas of interest for analysis.Main outcome measures:The primary measure was the change in average temperature of the observed area after the intervention.The secondary measures included periodic temperature changes every5 min and the temperature changes of the Governor Vessel and Bladder Meridian in the observed area after the intervention.Results:Significant interactions were observed between treatments and acupoints affecting temperature(P<0.001).The Acu-BL40 group showed a notably higher increase in mean temperature after 30 min compared to the Acu-LU5 and Mox-BL40 groups,with increases of 0.29(95%confidence interval[CI]=0.17 to 0.41)and 0.24(95%CI=0.08 to 0.41)℃,respectively.Conclusion:Acupuncture at BL40 acupoint can significantly increase the mean temperature in the observed area,highlighting the specific thermal effect of acupuncture compared to moxibustion in the lumbar area.This suggests a potential therapeutic benefit of acupuncture at BL40 for managing lumbar conditions.展开更多
The accelerated pace of natural and human-driven climate change presents profound challenges for Earth's systems.Oceans and ice sheets are critical regulators of climate systems,functioning as carbon sinks and the...The accelerated pace of natural and human-driven climate change presents profound challenges for Earth's systems.Oceans and ice sheets are critical regulators of climate systems,functioning as carbon sinks and thermal reservoirs.However,they are increasingly vulnerable to warming and greenhouse gas emissions.展开更多
Understanding the response of the phytoplankton community to climate change is essential for reservoir management.We analyzed a long-term data series(2009–2020)on the phytoplankton community in a large mesotrophic re...Understanding the response of the phytoplankton community to climate change is essential for reservoir management.We analyzed a long-term data series(2009–2020)on the phytoplankton community in a large mesotrophic reservoir in the wet season to investigate the impacts of temperature and precipitation increases caused by climate change on the functioning and trait composition of the phytoplankton community.Over the last twelve years,the 3-month accumulative precipitation increased from 291.03 mm to 590.91 mm,and the surface water temperature increased from 25.06℃to 26.49℃in wet season,respectively.These changes caused a higher water level,stronger thermal stratification and lower nitrogen concentration in Daxi Reservoir.The dynamic equilibrium model indicated that the increased precipitation and water temperature-related environmental changes would result in a more diverse and productive phytoplankton community.The effects of increasing water temperature and precipitation on the niche complementarity and selection effects within the phytoplankton community were analyzed using structural equation model by means of the functional divergence index and functional evenness index,respectively,elucidating the reasons for the increase in cyanobacteria in the absence of a significant increase in nutrient levels.Based on these results,it is advisable that more stringent phosphorus control standards might be conducted to reduce the risks of cyanobacteria proliferation in the context of global warming.展开更多
In August 2019,accompanied by an Arctic warming event,elevated thunderstorms crossed over the North Pole(NP)and produced lightning.The northernmost stroke occurred less than 50 km from the NP,marking the closest strok...In August 2019,accompanied by an Arctic warming event,elevated thunderstorms crossed over the North Pole(NP)and produced lightning.The northernmost stroke occurred less than 50 km from the NP,marking the closest stroke to the NP ever recorded.Using ERA5 reanalysis data and satellite observations,we investigated the background and development mechanism of this event.Warm and moist air from low latitudes was transported northward to the vicinity of the North Pole by the 850-h Pa jet,resulting in convergence.Through the combined effects of frontal lifting and the presence of underlying cold air,the warm and moist air was lifted to heights above the melting layer,triggering elevated thunderstorms above the frontal boundary.These findings describe a strong link between warming events and thunderstorms,revealing the formation mechanisms of elevated thunderstorms in the Arctic.In the context of rapid Arctic warming,this study provides preliminary insights into the meteorological conditions conducive to thunderstorm formation in the region.展开更多
基金supported by the Natural Science Fund of China(31771724)the Key Research and Development Project of Shaanxi Province(2024NC-ZDCYL-01-10).
文摘The increase in soil temperature associated with climate change has introduced considerable challenges to crop production.Split nitrogen application(SN)represents a potential strategy for improving crop nitrogen use efficiency and enhancing crop stress resistance.Nevertheless,the precise interaction between soil warming(SW)and SN remains unclear.In order to ascertain the impact of SW on maize growth and whether SN can improve the tolerance of maize to SW,a two-year field experiment was conducted(2022-2023).The aim was to examine the influence of two SW ranges(MT,warming 1.40℃;HT,warming 2.75℃)and two nitrogen application methods(N1,one-time basal application of nitrogen fertilizer;N2,one third of base nitrogen fertilizer+two thirds of jointing stage supplemental nitrogen fertilizer)on maize root growth,photosynthetic characteristics,nitrogen use efficiency,and yield.The results demonstrated that SW impeded root growth and precipitated the premature aging of maize leaves following anthesis,particularly in the HT,which led to a notable reduction in maize yield.In comparison to N1,SN has been shown to increase root length density by 8.54%,root bleeding rate by 8.57%,and enhance root distribution ratio in the middle soil layers(20-60 cm).The interaction between SW and SN had a notable impact on maize growth and yield.The SN improved the absorption and utilization efficiency of nitrogen by promoting root development and downward canopy growth,thus improving the tolerance of maize to SW at the later stage of growth.In particular,the N2HT resulted in a 14.51%increase in the photosynthetic rate,a 18.58%increase in nitrogen absorption efficiency,and a 18.32%increase in maize yield compared with N1HT.It can be posited that the SN represents a viable nitrogen management measure with the potential to enhance maize tolerance to soil high-temperature stress.
基金Natural science foundation of Inner Mongolia(2024LHMS06018)The basic scientific research funding for directly affiliated universities in the Inner Mongolia(JY20250094)。
文摘A complex system is inherently high-dimensional.Recent studies indicate that,even without complete knowledge of its evolutionary dynamics,the future behavior of such a system can be predicted using time-series data(data-driven prediction).This suggests that the essential dynamics of a complex system can be captured through a low-dimensional representation.Virus evolution and climate change are two examples of complex,time-varying systems.In this article,we show that mutations in the spike protein provide valuable data for predicting SARS-CoV-2 variants,forecasting the possible emergence of the new macro-lineage Q in the near future.Our analysis also demonstrates that carbon dioxide concentration is a reliable indicator for predicting the evolution of the climate system,extending global surface air temperature(GSAT)forecasts through 2500.
基金funded by the National Key Research and Development Plan of China(No.2022YFE0127900)the National Natural Science Foundation of China(Nos.32071558,32171559)+2 种基金the Natural Science Foundation Key Project of Inner Mongolia Autonomous Region,China(No.2023ZD23)the Hulunbuir Science and Technology Plan Project(No.SF2022001)the Fundamental Research Funds of CAF(CAFYBB2023ZA002).
文摘Increasing temperatures and severe droughts threaten forest vitality globally.Prediction of forest response to climate change requires knowledge of the spatiotemporal patterns of monthly or seasonal climatic impacts on the growth of tree species,likely driven by local climatic aridity,climate trends,edaphic conditions,and the climatic adaption of tree species.The ability of tree species to cope with changing climate and the effects of environmental variables on growth trends and growth-climate relationships across diverse bioclimatic regions are still poorly understood for many species.This study investigated radial growth trends,interannual growth variability,and growth-climate sensitivity of two dominant tree species,Pinus tabulaeformis(PT)and Pinus sylvestris var.mongolica(PS),across a broad climatic gradient with a variety of soil properties in temperate Northern China.Using a network of 83 tree ring chronologies(54 for PT and 29 for PS)from 1971 to 2010,we documented that both species maintained constant growth trends at wet sites,while both displayed rapid declines at dry sites.We reported the species-specific drivers of spatial heterogeneity in growth trends,interannual growth variability,and growth-climate relationships.Calculated climatic variables and soil properties were identified as the most critical factors affecting the growth trends and growth-climate relationships.However,climatic variables play more essential roles than soil properties in determining the spatial heterogeneity of the growth-climate relationship.Lower clay content and higher soil nutrient regimes can exacerbate the moisture-related susceptibility of tree growth.Our findings highlight that soil properties emerged as important modulating factors to predict the drought vulnerability of forests in addition to climatic variables.Considering the continued climate warmingdrying trend in the future,both pines will face a more severe growth decline and increase in drought vulnerability at drier sites with lower clayed soil or higher nutrient regimes.
文摘The effects of different warm rolling(WR)reductions on the microstructure and mechanical properties of low-Cr FeCrAl alloys at both room and elevated temperatures were investigated.The study revealed that when the WR reduction is small,it effectively refines the grains and forms a large number of subgrains in the matrix,while also inducing the dissolution of the Laves phase.This enhances the mechanical properties of FeCrAl alloys primarily through grain refinement and solid solution strengthening.Conversely,with larger WR reductions,the grain refinement effect diminishes,but a significant number of Laves phases form in the matrix,strengthening the alloys primarily through precipitation strengthening.WR exhibited a remarkable enhancing effect on the comprehensive mechanical properties at both room and high temperatures,with a signi-ficant enhancement in ductility at high temperatures.Notably,a 10%WR reduction resulted in the optimal overall mechanical properties at both room and elevated temperatures.
基金supported by the Basic Science Center for Tibetan Plateau Earth System(No.41988101)the Science and Technology Plan Project of the Xizang Autonomous Region(No.XZ202201ZD0005G01)。
文摘The Tibetan Plateau(TP),known as the“Third Pole of Earth”,and its ecosystem is quite sensitive to climate change(Yao et al.,2012;Qiu,2008).In recent decades,the main TP has experienced warming and humidification(although there has been a drying trend in the southern region),and researchers anticipate that this change will continue in the future(Jiang et al.,2023;Sun et al.,2020;Chen et al.,2015).
基金Supported by Hetian Prefecture Regional-Level Planning Project(20220219)。
文摘[Objectives]To improve the thermal insulation performance of solar greenhouses in winter,enhance solar energy utilization efficiency,reduce additional carbon emissions,and lower winter heating costs for greenhouses.[Methods]An active heat storage and release water bag was added inside the solar greenhouse.Comparative experiments were conducted between the experimental greenhouse K1 equipped with the heat storage water bag and the control greenhouse K2 under different winter night weather conditions.[Results]On sunny days,the maximum temperature difference between K1 and K2 was 2.3℃,and the average temperature during the water bag's heat release period increased by 2.2℃;on cloudy days,the maximum temperature difference was 2.2℃,and the average temperature increased by 2.0℃;on snowy days,the maximum temperature difference was 1.8℃,and the average temperature increased by 1.6℃.Additionally,the heat storage capacities of the water bag on sunny,cloudy,and snowy days were 491.4,453.6,and 365.4 MJ,respectively.The corresponding nighttime heat release amounts were 378,302.4,and 226.8 MJ,respectively.The corresponding heat storage-release efficiencies were 76%,66.2%,and 62%,respectively.The service life of the heat storage water bag can reach 10 years,with an annual operating cost of approximately 2500 yuan.[Conclusions]By comprehensively analyzing the initial costs,operating expenses,and cost savings rate compared to coal burning for current main energy-saving heat storage and warming equipment in solar greenhouses,this study provides reference suggestions for the promotion,application,and selection of winter heat storage and warming equipment for solar greenhouses in different regions.Users can choose to install the equipment based on the performance characteristics of the heat storage water bag and their actual needs.
基金Material Parts Technology Development Program (20017461, Development and Performance Improvement of Air Operated Valve for 105 MPa Hydrogen Charging Station) funded by the Ministry of Trade,Industry and Energy(MOTIE, Republic of Korea)Korea Evaluation Institute of Industrial Technology (KEIT, Republic of Korea)+1 种基金financial support from the Korea Institute of Energy Technology Evaluation and Planning (KETEP)Ministry of Trade,Industry&Energy (MOTIE) of the Republic of Korea(RS-2024-00419764)。
文摘Lignocellulosic biomass is one of the viable solutions to alleviate the global warming. However, the limited utilization of biomass majorly focused on cellulose and hemicellulose restricts the economic and environmental feasibilities. To cope with this issue, we proposed an integrated process of co-producing 1,6-hexanediol(1,6-HDO) with tetrahydrofuran and adipic acid from biomass, referred to as Strategy A. To compare the impacts of lignin upgrading and feedstock, Strategy B, which co-produces tetrahydrofuran alone, and Strategy C, which is the traditional route to produce 1,6-HDO from fossil fuels, were used. Heat networks are also designed to reduce operating costs and indirect carbon emissions due to energy consumption, saving 87% and 83% of the heat and cooling requirements, respectively, in Strategy A. The market competitiveness of Strategy A was evaluated by determining the minimum selling price through techno-economic analysis, and sustainability was thoroughly investigated by quantifying the environmental impacts through both midpoint and endpoint life-cycle assessments(LCAs).Strategy A was found to be the most favorable both economically(USRDSCHARDOLLAR3,402/ton) and environmentally(-26.9 kg CO_(2)eq.). This indicates that lignin valorization is not only economically but also environmentally preferred. Finally, changes in economic and environmental feasibilities depending on economic, process, and environmental parameters were investigated using sensitivity and uncertainty analyses. The results of these analyses provide valuable insight into bio-based chemical production.
基金funded by the Swiss National Science Foundation(SNF 200020_182084).
文摘Mediterranean forest communities are particularly diverse but at risk due to their sensitivity to global warming.Understanding the long-term vulnerability of Mediterranean vegetation to climate change is crucial for conservation and management purposes.Studies on past changes of forest communities in response to climate change at ecologically meaningful resolutions(i.e.,decadal time scales) are therefore essential,but still very rare.The Holocene thermal maximum(HTM;ca.10,000-5,000 cal years before the present(BP)) may be used to study species and community responses to warmer conditions than during recent decades.We performed highresolution multiproxy palaeoecological analyses on sediments from crater Lake Mezzano in central Italy to reconstruct vegetation,diversity,and fire dynamics between 8,450 and 7,050 cal years BP.Ordination,crosscorrelation,and species-response analyses were used to investigate the response of Mediterranean forest communities to HTM climate warming,human impact,and fire.Vegetational changes prior to 7,450 cal years BP were driven by climate.Fagus sylvatica spread into mixed deciduous oak forests during the Early Holocene in response to declining seasonality(cooler summers and warmer winters).Subsequently,Fagus sylvatica declined and evergreen Quercus ilex expanded after 8,200 cal years BP when the climate became warmer.Although reduced,Fagus sylvatica remained important together with deciduous oaks.The co-existence of Fagus sylvatica and evergreen Quercus forests is extremely rare today.Human impact significantly affected forest vegetation after7,450 cal years BP,when Neolithic agricultural activities became important,ultimately extirpating these special communities but fostering the overall biodiversity.However,their past occurrence in several central Italian calderas during the HTM suggests that these environments provided habitats that permitted the thriving of cooltemperate forests of Fagus sylvatica under mesomediterranean conditions,with summers ca.1-2℃ warmer than today.Cool and moist calderas may thus become increasingly important for maintaining Mediterranean mesophilous forest species under global warming conditions.
文摘Emphasis on future environmental changes grows due to climate change,with simulations predicting rising river temperatures globally.For Poland,which has a long history of thermal studies of rivers,such an approach has not been implemented to date.This study used 9 Global Climate Models and tested three machine-learning techniques to predict river temperature changes.Random Forest performed best,with R^(2)=0.88 and lowest error(RMSE:2.25,MAE:1.72).The range of future water temperature changes by the end of the 21st century was based on the Shared Socioeconomic Pathway scenarios SSP2-4.5 and SSP5-8.5.It was determined that by the end of the 21st century,the average temperature will increase by 2.1°C(SSP2-4.5)and 3.7°C(SSP5-8.5).A more detailed analysis,divided by two major basins Vistula and Odra,covered about 90%of Poland's territory.The average temperature increase,according to scenarios SSP2-4.5 and SSP5-8.5 for the Odra basin rivers,is 1.6°C and 3.2°C and for the Vistula basin rivers 2.3°C and 3.8°C,respectively.The Vistula basin's higher warming is due to less groundwater input and continental climate influence.These findings provide a crucial basis for water management to mitigate warming effects in Poland.
基金supported by Academy of Finland(project 284931)the Finnish Cultural Foundation/Eva Barbara WilhelminaFoundation(Decision 27.2.2021).
文摘The acclimation capacity of Betula pendula and Betula pubescens was studied over 4 years in common gardens in central Italy(43°N)and southern(61°N)and northern Finland(67°N),representing drastically different photoperiod and climate in temperate,boreal and subarctic vegetation zones.Two study sites that differed in soil fertility were established at each location,giving a total of six common gardens.The birch material was micropropagated from naturally regenerated stands of B.pendula and B.pubescens from Susa Valley and Rochemolle Valley in northern Italy,Punkaharju in southern Finland and Kittilä in northern Finland.The plants were measured for height growth,stem diameter,leaf chlorophyll content,leaf herbivory and pathogen damage.The effects of soil fertility on the common garden results were also analyzed.The results showed high acclimation capacity of B.pendula and B.pubescens after a long-range transfer from southern to northern Europe,despite the major shift in climate and photoperiod.First-year growth on average was best in boreal southern Finland for all origins.Betula pendula grew more than B.pubescens in Italy and southern Finland,while B.pubescens grew more in northern Finland and better tolerated the northward transfer.The height growth of origins showed a clear latitude gradient from slowly growing northern to fast growing southern origins in the nursery and laboratory,but not in the field.Soil fertility explained a significant part of variation among locations not only for growth variables,but also for leaf chlorophyll content and leaf herbivory and pathogen damage.Leaf herbivore and pathogen damage was greatest in southern Finland.Our results demonstrate good survival of birch from northern Italy in Finnish conditions and support the possibility of long-range south-to-north transfer of Betula species to provide resistant planting material in boreal forests for the rapidly changing climate.
基金jointly supported by the National Key R&D Program of China(Grant No.2022YFE0209200)the National Natural Science Foundation of China(Grant Nos.U22A20562,42330607 and 41761144054)the National Large Scientific and Technological Infrastructure“Earth System Science Numerical Simulator Facility”(Earth-Lab)(https://cstr.cn/31134.02.EL)。
文摘Accurate quantification of life-cycle greenhouse gas(GHG)footprints(GHG_(fp))for a crop cultivation system is urgently needed to address the conflict between food security and global warming mitigation.In this study,the hydrobiogeochemical model,CNMM-DNDC,was validated with in situ observations from maize-based cultivation systems at the sites of Yongji(YJ,China),Yanting(YT,China),and Madeya(MA,Kenya),subject to temperate,subtropical,and tropical climates,respectively,and updated to enable life-cycle GHG_(fp)estimation.The model validation provided satisfactory simulations on multiple soil variables,crop growth,and emissions of GHGs and reactive nitrogen gases.The locally conventional management practices resulted in GHG_(fp)values of 0.35(0.09–0.53 at the 95%confidence interval),0.21(0.01–0.73),0.46(0.27–0.60),and 0.54(0.21–0.77)kg CO_(2)e kg~(-1)d.m.(d.m.for dry matter in short)for maize–wheat rotation at YJ and YT,and for maize–maize and maize–Tephrosia rotations at MA,respectively.YT's smallest GHG_(fp)was attributed to its lower off-farm GHG emissions than YJ,though the soil organic carbon(SOC)storage and maize yield were slightly lower than those of YJ.MA's highest SOC loss and low yield in shifting cultivation for maize–Tephrosia rotation contributed to its highest GHG_(fp).Management practices of maize cultivation at these sites could be optimized by combination of synthetic and organic fertilizer(s)while incorporating 50%–100%crop residues.Further evaluation of the updated CNMM-DNDC is needed for different crops at site and regional scales to confirm its worldwide applicability in quantifying GHG_(fp)and optimizing management practices for achieving multiple sustainability goals.
基金supported by the National Natural Science Foundation of China(No.42072211)the National Natural Science Foundation of China(No.42401048)the Third Xinjiang Scientific Expedition and Research Program(No.2021xjkk0302)。
文摘The Taklimakan Desert,located in the heart of central Asia,covers approximately 330000 km^(2),making it China's largest desert and the world's second-largest shifting desert(Dong et al.,2024).With an average annual precipitation of less than 100 mm and evaporation rates ranging from 2000 to 3000 mm(Yang et al.,2020),it is recognized as one of the driest regions on Earth,often referred to as the“sea of death”.
基金jointly supported by the National Natural Science Foundation of China(Grant Nos.42422502,42275038)the China Meteorological Administration Climate Change Special Program(Grant No.QBZ202306)。
文摘Extensive flooding swept across large areas of Central Asia,mainly over Kazakhstan and southwestern Russia,from late March to April 2024.It was reported to be the worst flooding in the area in the past 70 years and caused widespread devastation to society and infrastructure.However,the drivers of this record-breaking flood remain unexplored.Here,we show that the record-breaking floods were contributed by both long-term climate warming and interannual variability,with multiple climatic drivers at play across the synoptic to seasonal timescales.First,the heavy snowmelt in March 2024 was associated with above-normal preceding winter snow accumulation.Second,extreme rainfall was at a record-high during March 2024,in line with its increasing trend under climate warming.Third,the snowmelt and extreme rainfall in March were compounded by record-high soil moisture conditions in the preceding winter,which was a result of interannual variability and related to excessive winter rainfall over Central Asia.As climate warming continues,the interplay between the increasing trend of extreme rainfall,interannual variations in soil moisture pre-conditions,as well as shifting timing and magnitudes of spring snowmelt,will further increase and complicate spring flooding risks.This is a growing and widespread challenge for the mid-to high-latitude regions.
文摘Agroforestry systems,as composite ecosystems,possess dual characteristics of both forest and agricultural ecosystems.They have been widely recognized as an important land-use approach in agriculture and play a significant role in changing the climate.However,they also face limitations,including uncertainties related to future global climate change,land use,and land cover.This paper summarized the important role of agroforestry systems in the global carbon cycle and carbon balance from the methods and means used in the research on carbon storage and carbon balance and the research status of carbon storage and carbon balance in agroforestry ecosystems at home and abroad,and pointed out the problems that need to be paid attention to in future research.
基金supported by National Science Foundation of China(NSFC)[No.32001119].
文摘Global warming leads to snow cover loss in the alpine ecosystem,exposing seeds to extreme diurnal temperature fluctuations during the growing season.The risk of freezing increases as seeds have increased moisture content.Studying the survival mechanisms of seeds at low temperatures can help analyze changes in alpine meadow populations and target conservation efforts.Here,we used three species of Poaceae as a model to understand freezing stress.Fully imbibed Elymus dahuricus,Festuca elata,and Lolium multiflorum seeds were subjected to programmed cooling at fast and slow rates(-1.0/0.05℃/min)and then assessed for survival.Differential Scanning Calorimetry was used to analyze thermal transitions during cooling.HE-stained paraffin sections and a Transmission Electron Microscope were employed to observe internal morphology and ultrastructural changes.E.dahuricus seeds exhibited greater tolerance to low temperatures than those of the other two species,with an LT_(50)of approximately-20℃for both cooling rates and maintained relatively intact ultrastructure.The observed the low-temperature exotherm(LTE)correlated with seed survival,with viability decreasing extensively below LTE.Fast cooling caused fewer changes to seed morphology and ultrastructure than slow cooling,suggesting that the primary survival mechanism during fast cooling is freezing avoidance through supercooling.Seeds exhibited greater freeze tolerance under slow than fast cooling,primarily by migrating intracellular water to extracellular spaces where it froze,causing considerable damage to cell ultrastructure and forming apparent cavities in some seeds.
基金funded by the National Key Research and Development Program of China(No.2018YFC1704600)Top-notch Innovative Talent Cultivation Program of Zhejiang Chinese Medicine University(No.741100G00726)。
文摘Background:There is a gap in understanding the effects of different acupoints and treatment methods(acupuncture and moxibustion)on microcirculatory changes in the lumbar region.Objective:This study aimed to assess the thermal effects of acupuncture at Weizhong(BL40),with acupuncture at Chize(LU5)and moxibustion at both acupoints as control interventions.Design,setting,participants and interventions:In this randomized controlled trial,140 healthy participants were equally divided into four groups:acupuncture at BL40(Acu-BL40),acupuncture at LU5(Acu-LU5),moxibustion at BL40(Mox-BL40)and moxibustion at LU5(Mox-LU5).Participants underwent a 30-minute session of their assigned treatment.Infrared thermal imaging was used to collect temperature data on the areas of interest for analysis.Main outcome measures:The primary measure was the change in average temperature of the observed area after the intervention.The secondary measures included periodic temperature changes every5 min and the temperature changes of the Governor Vessel and Bladder Meridian in the observed area after the intervention.Results:Significant interactions were observed between treatments and acupoints affecting temperature(P<0.001).The Acu-BL40 group showed a notably higher increase in mean temperature after 30 min compared to the Acu-LU5 and Mox-BL40 groups,with increases of 0.29(95%confidence interval[CI]=0.17 to 0.41)and 0.24(95%CI=0.08 to 0.41)℃,respectively.Conclusion:Acupuncture at BL40 acupoint can significantly increase the mean temperature in the observed area,highlighting the specific thermal effect of acupuncture compared to moxibustion in the lumbar area.This suggests a potential therapeutic benefit of acupuncture at BL40 for managing lumbar conditions.
文摘The accelerated pace of natural and human-driven climate change presents profound challenges for Earth's systems.Oceans and ice sheets are critical regulators of climate systems,functioning as carbon sinks and thermal reservoirs.However,they are increasingly vulnerable to warming and greenhouse gas emissions.
基金Supported by the National Natural Science Foundation of China(Nos.U22A20616,32071573)。
文摘Understanding the response of the phytoplankton community to climate change is essential for reservoir management.We analyzed a long-term data series(2009–2020)on the phytoplankton community in a large mesotrophic reservoir in the wet season to investigate the impacts of temperature and precipitation increases caused by climate change on the functioning and trait composition of the phytoplankton community.Over the last twelve years,the 3-month accumulative precipitation increased from 291.03 mm to 590.91 mm,and the surface water temperature increased from 25.06℃to 26.49℃in wet season,respectively.These changes caused a higher water level,stronger thermal stratification and lower nitrogen concentration in Daxi Reservoir.The dynamic equilibrium model indicated that the increased precipitation and water temperature-related environmental changes would result in a more diverse and productive phytoplankton community.The effects of increasing water temperature and precipitation on the niche complementarity and selection effects within the phytoplankton community were analyzed using structural equation model by means of the functional divergence index and functional evenness index,respectively,elucidating the reasons for the increase in cyanobacteria in the absence of a significant increase in nutrient levels.Based on these results,it is advisable that more stringent phosphorus control standards might be conducted to reduce the risks of cyanobacteria proliferation in the context of global warming.
基金supported by the National Key Research and Development Program of China(2023YFC3007703)National Natural Science Foundation of China(Grant Nos.41675066,42394122)+1 种基金CAS Project of Stable Support for Youth Team in Basic Research Field(YSRR-018)the Chinese Meridian Project。
文摘In August 2019,accompanied by an Arctic warming event,elevated thunderstorms crossed over the North Pole(NP)and produced lightning.The northernmost stroke occurred less than 50 km from the NP,marking the closest stroke to the NP ever recorded.Using ERA5 reanalysis data and satellite observations,we investigated the background and development mechanism of this event.Warm and moist air from low latitudes was transported northward to the vicinity of the North Pole by the 850-h Pa jet,resulting in convergence.Through the combined effects of frontal lifting and the presence of underlying cold air,the warm and moist air was lifted to heights above the melting layer,triggering elevated thunderstorms above the frontal boundary.These findings describe a strong link between warming events and thunderstorms,revealing the formation mechanisms of elevated thunderstorms in the Arctic.In the context of rapid Arctic warming,this study provides preliminary insights into the meteorological conditions conducive to thunderstorm formation in the region.
