Comprehensively revealing the intensity of drought propagation from meteorological to hydrological drought is crucial for effective drought monitoring and management.However,existing assessments often fail to integrat...Comprehensively revealing the intensity of drought propagation from meteorological to hydrological drought is crucial for effective drought monitoring and management.However,existing assessments often fail to integrate multiple drought characteristics,resulting in incomplete evaluations.To address this limitation,this study introduced the drought comprehensive propagation intensity(DCPI)index,a systematic tool that quantifies propagation intensity and incorporates five drought characteristic indicators(drought frequency,total duration,maximum duration,coverage,and degree)to assess the comprehensive drought intensity in the upper Shiyang River Basin,China from 1961 to 2023.The results indicated that pre-1980s drought propagation was relatively weak(DCPI<0.964),reflecting stable hydrological homeostasis.After the 1980s,the intensity significantly increased,peaking at 5.530(rather strong drought)in the 2000s due to human-induced alterations in surface runoff and ecological changes.Spatially,the western tributaries(e.g.,the Xida River Watershed)presented stronger hydrological drought intensity,whereas the eastern tributaries(e.g.,the Huangyang,Gulang,and Dajing river watersheds)presented higher meteorological drought intensity.The DCPI values decreased from west to east,with near peer-to-peer propagation observed in the Dongda,Huangyang,and Jinta river watersheds,suggesting minimal human interference.A nonlinear relationship between meteorological and hydrological droughts was identified,with severe drought frequency and duration emerging as critical drivers of propagation intensity.Notably,trends of meteorological humidification coexist with hydrological aridification,highlighting systemic challenges for water resource management.The DCPI framework enhances the understanding of drought mechanisms by enabling a structured evaluation of drought impacts,which is essential for developing effective water resource strategies and ecological restoration efforts in arid areas.This study underscores the importance of integrating multi-dimensional drought characteristics to improve prediction accuracy and inform policy decisions.展开更多
Drought stress is one of the factors limiting pepper production in water-stressed regions.It affects growth and development by inducing morphological,biochemical,and physiological changes.Breeding drought-resistant va...Drought stress is one of the factors limiting pepper production in water-stressed regions.It affects growth and development by inducing morphological,biochemical,and physiological changes.Breeding drought-resistant varieties is a sustainable strategy to mitigate drought,therefore,reliable evaluation systems are essential to identify drought-resistant pepper accessions.In this study,100 pepper accessions were screened for drought resistance under highly controlled conditions at the vegetative stage.Selected accessions exhibited a significantly higher recovery rate after water-deficiency and showed durable resistance under greenhouse conditions.Correlation analysis between drought resistance with morphological and physiological traits showed that the recovery rate was positively correlated with root length and relative water content,and negatively correlated with plant height and leaf area.Gene expression analysis showed that the drought-resistant accession exhibited higher expression levels of drought-responsive genes under drought stress.Among the accessions,anthocyanin-accumulating peppers showed more significant drought resistance compared to other accessions.When the MYB transcription factor An2,the genetic determinant of anthocyanin accumulation,was silenced,drought resistance was significantly reduced.Drought-resistant accessions with favorable adaptive traits identified in this study will be valuable in various breeding programs to generate new pepper cultivars to cope with climate change.展开更多
Water scarcity severely constrains the genetic potential of wheat yield worldwide.Proline is among the most versatile stress-related metabolites in plants,and targeting genes involved in proline synthesis and degradat...Water scarcity severely constrains the genetic potential of wheat yield worldwide.Proline is among the most versatile stress-related metabolites in plants,and targeting genes involved in proline synthesis and degradation represents a promising strategy for developing drought-tolerant wheat genotypes.This study evaluates the performance of the photosynthetic apparatus in transgenic wheat line with RNAi-mediated suppression of proline dehydrogenase(ProDH)and in the original(wild-type)genotype,under both drought and recovery conditions.Drought was induced at the flowering stage by lowering soil moisture to 30%field capacity for 7 days,compared with 70%field capacity in control plants.Measurements were taken at the onset and end of drought period and 7 days after subsequent recovery.The results demonstrated that drought-treated transgenic plants exhibited improved responses to both the short-term and prolonged effects of stress.Relative water content and chlorophyll levels in the leaves of the transgenic plants changed to a significantly lesser extent.The CO2 assimilation rate in the leaves of transgenic plants was significantly higher than in the wild type under both drought stress and recovery.The transgenic plants also showed superior water-use efficiency during photosynthesis under both conditions.While superoxide dismutase and ascorbate peroxidase activities in leaf chloroplasts increased similarly in both genotypes under drought,they returned to control levels more rapidly in the transgenic plants during recovery.Drought-induced productivity reduction was also significantly lower in the transgenic plants.These findings suggest that RNAi-mediated suppression of ProDH improved photosynthetic performance and grain yield in wheat under drought conditions.展开更多
Frequent droughts pose considerable threat to global forest carbon uptake,but little is known about the response of forest carbon fluxes in climatic transition zones to seasonal drought.In this study,the responses of ...Frequent droughts pose considerable threat to global forest carbon uptake,but little is known about the response of forest carbon fluxes in climatic transition zones to seasonal drought.In this study,the responses of carbon fluxes to seasonal drought in two natural forests(Quercus aliena var.acute serrata Maxim and Pinus tabuliformis Carr.)in the Baotianman Nature Reserve were investigated.The Q.aliena forest exhibited a high resilience with stable gross primary productivity(GPP).However,ecosystem respiration(Re)significantly declined by 18.4%compared with normal years,leading to an increase in net carbon sequestration capacity of 4.1%.This resilience was attributed to its deep root system accessing soil water(SWC_(50cm))to sustain stomatal openness,coupled with the efficient utilization of photosynthetically active radiation to drive photosynthesis.In contrast,the P.tabuliformis forest,which relied on shallow soil moisture(SWC_(20cm)),experienced simultaneous decreases in both GPP and Re during drought,with a sharply greater decrease in GPP,resulting in low net carbon sink capacity.Further analysis revealed that the Q.aliena forest prioritized carbon assimilation through a deep water-stomatal synergy strategy(anisohydric behavior),whereas the P.tabuliformis forest adopted an isohydric strategy favoring water conservation at the expense of carbon fixation efficiency.These findings highlight distinct mechanisms underlying drought adaptation between forest types,providing critical insight into optimizing forest carbon cycle models and selecting drought-resistant species under the influence of climate change.展开更多
The formation of wood is affected by the growing season and the environment.Ring-porous tree species have distinct earlywood-latewood differences.However,it is not clear how early wood and latewood respond to drought ...The formation of wood is affected by the growing season and the environment.Ring-porous tree species have distinct earlywood-latewood differences.However,it is not clear how early wood and latewood respond to drought and the differences in adaptation.Therefore,based on the analyses of phenology,growth,and xylem development over a year,xylem development in Fraxinus mandshurica was divided into earlyw ood,transition,and latewood stages.Variation patterns of 38 wood indices from 31 genotypes indicated that the formation of wood tissues was inhibited,and the proportion of xylem cells was affected by drought at each stage.However,soluble sugar affected osmotic regulation only during drought across early wood and transition stages.To maintain water and nutrient transport during drought and to resist embolism risk,drought in the early wood stage leads to varying degrees of early wood vessel diameter reduction,with pits enlarging to compensate.In contrast,during the late wood stage,drought causes latewood vessel diameter to increase and pits to shrink accordingly.In addition,the results indicate that several wood indices correlate with drought resistance at each stage,but early wood vessel diameter,soluble sugar,and latewood ves sel diameters exhibited the strongest correlations in the early wood,transition,and latewood stages.These findings provide clues to understanding plant survival strategies under drought stress and are of significance for plant ecology research on the growth and adaptation of tree species under climate change.展开更多
Drought stress orchestrates a phosphorylation-dependent signaling cascade that reprograms transcriptional networks to enhance crop resilience.Through a large-scale transgenic screening,we identified ZmCRK5A,a Ca^(2+)-...Drought stress orchestrates a phosphorylation-dependent signaling cascade that reprograms transcriptional networks to enhance crop resilience.Through a large-scale transgenic screening,we identified ZmCRK5A,a Ca^(2+)-independent calcium-dependent protein kinase(CDPK)-related kinase,as a master regulator of drought tolerance in maize.Mechanistically,ZmCRK5A directly phosphorylates the MYB transcriptional repressor ZmSMH4(Single MYB Histone 4)at three conserved serine residues(Ser42/43/59)within its SANT domain,as demonstrated by in vitro kinase assays and site-directed mutagenesis.This post-translational modification abolishes Zm SMH4's DNA-binding capacity to ACC cis-elements,thereby de-repressing the potassium influx channel gene Zm KCH1(K^(+)Channel 1).Functional validation revealed that Zm KCH1 overexpression confers drought resilience through optimized stomatal dynamics and water retention,whereas clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)-generated zmkch1 mutants display hypersensitivity to water deficit.Crucially,field evaluations demonstrated preserved grain yield alongside enhanced drought tolerance in plants with activated Zm CRK5A-Zm SMH4-Zm KCH1 signaling.Our findings delineate a kinase-transcription factor-ion channel axis that dynamically fine-tunes drought responses while maintaining productivity,providing a strategic framework for engineering stress-adapted crops without yield penalties.展开更多
Non-structural carbohydrates(NSCs)are critical for plant drought adaptation,but their environmental drivers under prolonged drought remains unclear.We investigated seasonal NSCs dynamics in the leaf,stem and root of P...Non-structural carbohydrates(NSCs)are critical for plant drought adaptation,but their environmental drivers under prolonged drought remains unclear.We investigated seasonal NSCs dynamics in the leaf,stem and root of Picea crass ifolia(Qinghai spruce)during the growing seasons of2021-2023 under intensifying drought at three altitudes in Qilian Mountains,Northwest China.Our results revealed synchronous seasonal patterns in soluble sugar,starch,and total non-structural carbohydrate within the same year,contrasting with marked altitudinal disparities.As drought progressed(from 2021 to 2023),soluble sugars initially increased(2022)then declined(2023),while starch showed consistent reduction(except leaves).Moreover,the altitude of peak NSCs concentrations shifted from 3200 m in 2021to 2700 m in 2023.In particular,prolonged drought alters the environmental factors affecting NSCs.NSCs demonstrated significant positive correlations with soil temperature during humid 2021,then negatively with air temperature,vapor pressure deficit,and precipitation during 2022's initial drought,whereas under 2023's persistent drought conditions,soil temperature and water content emerged as dominant drivers.Concurrently,the ratio of soluble sugar to starch transitioned from air temperature and precipitation associations(2021-2022)to soil parameter dependence in2023.These findings provide new insights into the seasonal carbon dynamics of Qinghai spruce and the environmental response mechanisms under increasing drought stress,contributing to a better understanding of tree physiological adaptations in drought stress.展开更多
Drought stress is a serious natural challenge for tea plants that significantly affects tea yield and quality.miR171s play critical roles in plant stress responses,however,their role in drought stress tolerance in tea...Drought stress is a serious natural challenge for tea plants that significantly affects tea yield and quality.miR171s play critical roles in plant stress responses,however,their role in drought stress tolerance in tea plants(Camellia sinensis)is poorly understood.This study experimentally verified the expression patterns of csn-miR171b-3p_2 and its target,scarecrow-like(SCL).We found that csn-miR171b-3p_2 could target and regulate CsSCL6-4 to play an important role in the defense against drought stress in tea plants.CsSCL6-4 is located in the nucleus and is selfactivated in vivo.In addition,we obtained 819 putative binding regions of CsSCL6-4 using DNA affinity purification sequencing analysis,which were assigned to 786 different genes,four of which were drought-resistant genes(CsPrx,CsSDR,CsFAD7,and CsCER1).Yeast one-hybrid and dual-luciferase reporter assays revealed that CsSCL6-4 directly promoted the expression of these four drought resistance genes by binding motifs 1/2/3 in their promoter regions.Both overexpression and suppression of CsSCL6-4 proved that CsSCL6-4 participated in the defense against drought stress in tea plants by regulating the expression of CsPrx,CsSDR,CsFAD7,and CsCER1.In addition,suppression of csn-miR171b-3p_2 expression significantly increased the expression of CsSCL6-4 and activated CsSCL6-4-bound gene transcription under drought stress.Therefore,the csn-miR171b-3p_2-CsSCL6-4 module participates in tea plant resistance to drought stress by promoting the expression of drought resistance genes.Our results revealed the function of csn-miR171b-3p_2 in tea plants and provided new insights into the mechanism of tea plant resistance to drought stress.展开更多
Drought stress significantly impedes apple growth,development,and yield,leading to substantial economic losses within the global apple industry.Malus prunifolia(Mp),a commonly utilized apple rootstock,has shown promis...Drought stress significantly impedes apple growth,development,and yield,leading to substantial economic losses within the global apple industry.Malus prunifolia(Mp),a commonly utilized apple rootstock,has shown promise in augmenting cultivated apple resistance to abiotic stress.Although Alfin-like(ALs)proteins have demonstrated pivotal roles in dicotyledonous plants'response to abiotic stresses,knowledge about AL genes in apple rootstocks is limited,and their functions remain largely elusive.In this study,we identified and characterized 10 MpAL gene members in the apple rootstock genome,confirming their localization within the nucleus.Our investigation revealed the significant regulation of MpALs'expression under drought and abscisic acid(ABA)stresses in M.prunifolia.In this study,one of the members,MpAL1,was selected for further exploration in Arabidopsis and apple to explore its potential function in response to drought and ABA stresses.The results showed that overexpression-MpAL1 transgenic apple calli grew significantly better than WT and MpAL1-RNAi lines,which regulates the accumulation of H_(2)O_(2)and O_(2).-levels.Additionally,transgenic Arabidopsis plants overexpressing MpAL1 exhibited positively regulating antioxidant enzymes activities under stress treatments.Further study showed that silencing MpAL1 in apple plants showed obvious chlorosis in leaves,and accumulation of reactive oxygen species under drought stress.Moreover,our detailed analysis established that MpAL1 regulates several drought and ABA-responsive genes,exerting an influence on their expression in transgenic apple.Collectively,our findings identify MpAL1 as a positive regulator that increases drought stress in apple,shedding light on its potential significance in bolstering drought resistance in this fruit crop.展开更多
Flash droughts(FDs)develop quickly and can rapidly deplete soil moisture,posing significant threats to agriculture and pastoral systems.To investigate the spatiotemporal characteristics and development mechanisms of F...Flash droughts(FDs)develop quickly and can rapidly deplete soil moisture,posing significant threats to agriculture and pastoral systems.To investigate the spatiotemporal characteristics and development mechanisms of FDs in Inner Mongolia,China,and to assess the roles of key meteorological drivers in driving soil moisture variability,FD events were identified using root-zone soil moisture data during the growing seasons from 1982 to 2022.The results indicate the presence of five FD hotspot regions,located in the southern Alxa Plateau,the Hetao Plain in Bayannur,the northwestern Xilingol Plain,the western Liaohe River Plain,and the northern Da Hinggan Ling.Over 41 years,FDs occurred on average 7.44 events across the study area,with a mean duration of 9.17 pentads(1 pentad equals 5 days).The duration exhibited a significant increasing trend of 0.39 pentads/10 years.FD onsets primarily lasted for 2-3 pentads.During the FD development phase,precipitation and evapotranspiration decreased while temperature,potential evapotranspiration,incoming solar radiation,and vapor pressure deficit increased.The dominant meteorological drivers of FD development exhibited notable spatial heterogeneity across hotspot regions,and vapor pressure deficit consistently was the most influential factor.These findings improve the understanding of climate drivers at different stages of FD development and provide scientific support for early warning and prevention of droughts in Inner Mongolia.展开更多
Drought influences carbon fixation by plants.Therefore,elucidating its impact on carbon fluxes in plants at the ecosystem level is crucial for assessing their role in mitigating climate change.Using carbon fluxes and ...Drought influences carbon fixation by plants.Therefore,elucidating its impact on carbon fluxes in plants at the ecosystem level is crucial for assessing their role in mitigating climate change.Using carbon fluxes and environmental factor data from FLUXNET sites,we analyzed the influence of drought on carbon fluxes,their drivers,time-lag effects,and recovery times across various climatic regions and seasons.Results showed drought significantly decreased gross primary production(GPP),ecosystem respiration,and net ecosystem productivity in arid regions but slightly increased carbon sequestration in humid regions.Summer droughts negatively affected vegetation carbon fluxes,partly offset by the positive impact of spring droughts.Nonforest carbon fluxes were more susceptible to drought effects than forest fluxes.Soil water content(SWC)was the main influence on changes in arid regions,whereas vapor pressure deficit(VPD)dominated humid regions.Decreased SWC and increased VPD reduced carbon sequestration in arid regions but increased it in humid regions.Increased VPD reduced GPP,leading to forest carbon loss,whereas decreased SWC reduced GPP,leading to nonforest carbon loss.The lag time of the drought effects on carbon fluxes was longer in humid regions(19.44 d)than in arid regions(14.71 d).Compared to nonforest areas(16.74 d and 57 d for drought lag and recovery time,respectively),forest areas had a longer lag(18.81 d)and recovery time(92 d).The findings revealed discrepancies in the main factors regulating vegetation carbon fluxes during droughts between arid and humid regions and between forest and nonforest ecosystems.These insights provide a new perspective on understanding and simulating carbon-climate feedback.Enhancing ecosystem diversity is a feasible measure to increase drought resistance.展开更多
Tajikistan,a mountainous country and a vital water tower for Central Asia,is becoming increasingly vulnerable to snow drought under climate change,threatening its snow-and glacier-fed streamflow.Yet,the impacts of sno...Tajikistan,a mountainous country and a vital water tower for Central Asia,is becoming increasingly vulnerable to snow drought under climate change,threatening its snow-and glacier-fed streamflow.Yet,the impacts of snow drought on the regional hydrology remain insufficiently understood.In this study,we integrated multisource data,including the Fifth Generation European Centre for Medium-Range Weather Forecasts Atmospheric Reanalysis for Land Applications(ERA5-Land)data and hydrological station data,to systematically assess the snow drought patterns and their impacts on streamflow during 1950–2023.We identified snow drought events based on precipitation and snow fraction anomalies relative to climatological means and classified them into warm snow drought,dry snow drought,and warm&dry snow drought.The results revealed that snow drought was a recurrent phenomenon,occurring in 51.70%of the years during the study period,with warm&dry snow drought accounting for 21.90%of the total events.Both the frequency and severity exhibited pronounced spatial variability,largely governed by the elevation and snowfall fraction.Specifically,the frequency of warm snow drought was negatively correlated with the snowfall fraction,decreasing on average by 0.20 per unit increase in snowfall fraction,whereas the frequency of dry snow drought was positively correlated,increasing by 0.07 per unit increase.The streamflow analysis results demonstrated that snow drought typically reduced the warm-season discharge by 5.00%–18.00%in certain rivers,thereby exacerbating the water stress during the dry season.The results of this study advance our understanding by explicitly linking the types of snow drought to hydrological responses in Central Asia’s high mountains,providing a scientific basis for climate adaptation and sustainable water resource management in Tajikistan.展开更多
Forest ecosystems are increasingly susceptible to droughts and nitrogen(N)deposition.However,the effects of N addition on the growth of bamboo under drought stress remain unclear.This study conducted a comprehensive f...Forest ecosystems are increasingly susceptible to droughts and nitrogen(N)deposition.However,the effects of N addition on the growth of bamboo under drought stress remain unclear.This study conducted a comprehensive factorial experiment to investigate the combined effects of drought and N addition on the growth of Moso bamboo(Phyllostachys edulis)seedlings.Six treatment combinations were established:0 mg·kg^(-1) N with 80%–85%field capacity(FC)soil moisture,0 mg·kg^(-1) N with 50%–55%FC,0 mg·kg^(-1) N with 30%–35%FC,100 mg·kg^(-1) N with 80%–85%FC,100 mg·kg^(-1) N with 50%–55%FC,and 100 mg·kg^(-1) N with 30%–35%FC.The results revealed that drought altered the soil microbial community structure and significantly reduced the biomass of Moso bamboo seedlings.Notably,N addition mitigated the adverse effects of drought on bamboo growth in general.Specifically,N addition alleviated the negative effects of drought on root biomass but aggravated them on leaf biomass of Moso bamboo seedlings,and with the intensification of drought stress,this effect was weakened.Furthermore,sucrose and urease exerted dominant and direct influences on the total biomass.The results underscore the pivotal role of N in facilitating plant drought tolerance,suggesting that the interplay between drought and N addition in plant growth should be considered in the context of changing environmental conditions,and offering novel perspectives on sustainable management strategies for bamboo forests.展开更多
Prolonged droughts have emerged as a major impediment to the revitalization of pastoral regions worldwide because they significantly augment their susceptibility to the deleterious effects of global climate change,ove...Prolonged droughts have emerged as a major impediment to the revitalization of pastoral regions worldwide because they significantly augment their susceptibility to the deleterious effects of global climate change,overgrazing,and land degradation.This study,conducted in 106 pastoral villages across 33 pastoral banners of Inner Mongolia Autonomous Region of China between August 2021 and October 2022,used a community resilience evaluation indicator system to assess drought resistance.By calculating a community resilience index,the research explored influencing factors and proposed countermeasures,aiming to enhance resilience to prolonged drought.The results revealed three key findings.1)Pastoral areas exhibited a limited degree of community resilience to drought disasters(overall score=0.28),with resilience levels forming a pyramid-shaped hierarchy.2)Dimensional analysis showed that resilience scores decreased sequentially across five domains:social(0.53)>cultural(0.44)>environmental(0.38)>economic(0.32)>management(0.27).These results highlight the crucial role of economic and management resilience in enhancing community resilience,particularly when accompanied by pre-and post-disaster government support and social security,both of which must be improved.3)Key factors influencing community resilience included geographical location,traffic accessibility,and frequency and severity of droughts.From a drought resilience perspective,targeted strategies and recommendations are proposed to provide novel and practical approaches for achieving sustainable development in pastoral areas and rural regions as a whole.展开更多
As part of my master’s programme in resource use and environmental science at China Agricultural University,I had the privilege of joining a study trip to the Shiyang River Basin and its surrounding areas from 17 to ...As part of my master’s programme in resource use and environmental science at China Agricultural University,I had the privilege of joining a study trip to the Shiyang River Basin and its surrounding areas from 17 to 21 July 2025.This trip to Gansu Province was organised under the China-Africa Joint Centre for Agricultural Demonstration and Training in Arid Regions programme,an initiative aligned with President Xi Jinping’s call for deeper China-Africa cooperation.展开更多
The Yili River Basin in Northwest China is a crucial ecological security barrier,yet it faces frequent droughts amid global climate change,posing significant threats to food security and ecological stability.However,t...The Yili River Basin in Northwest China is a crucial ecological security barrier,yet it faces frequent droughts amid global climate change,posing significant threats to food security and ecological stability.However,the spatiotemporal variations and driving mechanisms of drought in the basin remain unclear.Based on the monthly Standardized Precipitation Evapotranspiration Index(SPEI),this study employed the Run-Length theory to identify drought events in the basin during 1980-2020,applied statistical and time-series analyses to investigate the spatiotemporal variations,trends,periodicity,and persistence of drought,and explored the underlying drivers associated with meteorological factors and large-scale atmospheric circulation patterns.The results showed that droughts in the Yili River Basin are more severe in spring and summer.Droughts in the central and southwestern regions exhibit greater severity,with shorter durations and stronger intensity.Drought conditions have generally worsened(Sen’s slope=−0.146/10 yr),with notable intensification since 2005,especially in the northwestern region.Spring droughts(Sen’s slope=−0.213/10 yr)and summer droughts(Sen’s slope=−0.169/10 yr)have intensified at most stations,while autumn and winter droughts have eased.In the future,droughts are expected to alleviate overall,but summer droughts may continue to intensify.The Yili River Basin exhibits two primary drought periods of 9 yr and 21 yr,with primary periods in autumn(20 yr)and winter(20 yr)being longer than those in spring(10 yr)and summer(17 yr).Finally,droughts are impacted by both meteorological factors and large-scale atmospheric circulation patterns.Rising temperatures and uneven precipitation have intensified droughts.The SPEI exhibits a co-phase relationship with the North Atlantic Oscillation and an antiphase relationship with the East Central Tropical Pacific Sea Surface Temperature.Therefore,close monitoring and mitigation are necessary for spring and summer droughts,with a focus on the central and southwestern areas in autumn and winter.展开更多
Understanding the evolution and lag effects of droughts is critical to effective drought warning and water resources management.However,due to limited hydrological data,few studies have examined hydrological droughts ...Understanding the evolution and lag effects of droughts is critical to effective drought warning and water resources management.However,due to limited hydrological data,few studies have examined hydrological droughts and their lag time from meteorological droughts at a daily scale.In this study,precipitation data were collected to calculate the standardized precipitation index(SPI),and runoff data simulated by the variable infiltration capacity(VIC)model were utilized to compute the standardized runoff index(SRI).The three-threshold run theory was used to identify drought characteristics in China.These drought characteristics were utilized to investigate spatiotemporal variations,seasonal trends,and temporal changes in areas affected by meteorological and hydrological droughts.Additionally,the interconnections and lag effects between meteorological and hydrological droughts were explored.The results indicated that(1)drought occurred during approximately 28%of the past 34 years in China;(2)drought conditions tended to worsen in autumn and weaken in winter;(3)drought-affected areas shifted from northwest to northeast and finally to southern China;and(4)the correlation between meteorological and hydrological droughts was lower in the northwest and higher in the southeast,with all correlation coefficients exceeding 0.7.The lag times between meteorological and hydrological droughts were longest(5 d)in the Yangtze River,Yellow River,and Hai River basins,and shortest(0 d)in the Tarim River Basin.This study provides a scientific basis for effective early warning of droughts.展开更多
Accurate drought assessment demands thoughtful consideration of drought definition first of all.Drought is commonly defined as a prolonged period of below-average precipitation leading to water shortages that impact e...Accurate drought assessment demands thoughtful consideration of drought definition first of all.Drought is commonly defined as a prolonged period of below-average precipitation leading to water shortages that impact ecosystems,agriculture,and human societies.However,meteorologists,hydrologists,and agronomists often use different criteria to define drought,depending on their specific focus areas.For example,hydrologists define drought according to water deficits in some components of the hydrological cycle(such as precipitation,soil moisture,river flow,and groundwater)or its impacts on the level of services provided to public water supply,irrigation,or hydropower demands(Tate and Gustard,2000).Differences in drought definitions may result in great uncertainties in drought assessment(Satoh et al.,2021).We cannot expect the existence of any workable generalized objective definition of drought(Lloyd-Hughes,2014).展开更多
Frequent drought events severely restrict global crop productivity,especially those occurring in the reproductive stages.Moderate drought priming during the earlier growth stages is a promising strategy for allowing p...Frequent drought events severely restrict global crop productivity,especially those occurring in the reproductive stages.Moderate drought priming during the earlier growth stages is a promising strategy for allowing plants to resist recurrent severe drought stress.However,the underlying mechanisms remain unclear.Here,we subjected wheat plants to drought priming during the vegetative growth stage and to severe drought stress at 10 days after anthesis.We then collected leaf samples at the ends of the drought priming and recovery periods,and at the end of drought stress for transcriptome sequencing in combination with phenotypic and physiological analyses.The drought-primed wheat plants maintained a lower plant temperature,with higher stomatal openness and photosynthesis,thereby resulting in much lower 1,000-grain weight and grain yield losses under the later drought stress than the non-primed plants.Interestingly,416 genes,including 27 transcription factors(e.g.,MYB,NAC,HSF),seemed to be closely related to the improved drought tolerance as indicated by the dynamic transcriptome analysis.Moreover,the candidate genes showed six temporal expression patterns and were significantly enriched in several stress response related pathways,such as plant hormone signal transduction,starch and sucrose metabolism,arginine and proline metabolism,inositol phosphate metabolism,and wax synthesis.These findings provide new insights into the physiological and molecular mechanisms of the long-term effects of early drought priming that can effectively improve drought tolerance in wheat,and may provide potential approaches for addressing the challenges of increasing abiotic stresses and securing food safety under global warming scenarios.展开更多
Global warming and rapid economic development have led to increased levels of disaster risk in China.Previous attempts at assessing drought risk were highly subjective in terms of assessment methods and selection of t...Global warming and rapid economic development have led to increased levels of disaster risk in China.Previous attempts at assessing drought risk were highly subjective in terms of assessment methods and selection of the assessment indicators and which resulted in appreciable uncertainty in the results of these risk assessments.Based on the assumption that areas with historically high drought losses are more likely to suffer future high drought losses,we develop a new drought risk assessment model that includes historical drought loss data.With this model,we map the regional differentiation of Chinese drought risk.Regions with high(extreme high)drought risk account for 4.3%of China’s area.Five significant high-risk areas have been identified:Northeast China,North China,the east part of Northwest China,the east part of Southwest China and a small part in the west of Northwest China.Areas with high and extreme high drought risk are dominant in the Heilongjiang Province,accounting for 32%of the total area,followed by the Ningxia Hui Autonomous Region,with 26%of total area.The contribution of each influencing factor has been quantified,which indicates that high-exposure and high-vulnerability account for the high-risk of drought.We recommend that measures like strengthening the protection of cultivated land and reducing dependence on the primary industry should be taken to mitigate to drought-induced losses.展开更多
基金supported by the National Natural Science Foundation of China(42475177,41877521)the National Key Research and Development Program of China(2023YFC3008505,2016YFA0602402).
文摘Comprehensively revealing the intensity of drought propagation from meteorological to hydrological drought is crucial for effective drought monitoring and management.However,existing assessments often fail to integrate multiple drought characteristics,resulting in incomplete evaluations.To address this limitation,this study introduced the drought comprehensive propagation intensity(DCPI)index,a systematic tool that quantifies propagation intensity and incorporates five drought characteristic indicators(drought frequency,total duration,maximum duration,coverage,and degree)to assess the comprehensive drought intensity in the upper Shiyang River Basin,China from 1961 to 2023.The results indicated that pre-1980s drought propagation was relatively weak(DCPI<0.964),reflecting stable hydrological homeostasis.After the 1980s,the intensity significantly increased,peaking at 5.530(rather strong drought)in the 2000s due to human-induced alterations in surface runoff and ecological changes.Spatially,the western tributaries(e.g.,the Xida River Watershed)presented stronger hydrological drought intensity,whereas the eastern tributaries(e.g.,the Huangyang,Gulang,and Dajing river watersheds)presented higher meteorological drought intensity.The DCPI values decreased from west to east,with near peer-to-peer propagation observed in the Dongda,Huangyang,and Jinta river watersheds,suggesting minimal human interference.A nonlinear relationship between meteorological and hydrological droughts was identified,with severe drought frequency and duration emerging as critical drivers of propagation intensity.Notably,trends of meteorological humidification coexist with hydrological aridification,highlighting systemic challenges for water resource management.The DCPI framework enhances the understanding of drought mechanisms by enabling a structured evaluation of drought impacts,which is essential for developing effective water resource strategies and ecological restoration efforts in arid areas.This study underscores the importance of integrating multi-dimensional drought characteristics to improve prediction accuracy and inform policy decisions.
基金supported by Cooperative Research Program for Agriculture Science and Technology Development(Grant No.RS-2020-RD009069)Rural Development Administration and the National Research Foundation of Korea(Grant No.RS-2021-NR059647),Republic of Korea.
文摘Drought stress is one of the factors limiting pepper production in water-stressed regions.It affects growth and development by inducing morphological,biochemical,and physiological changes.Breeding drought-resistant varieties is a sustainable strategy to mitigate drought,therefore,reliable evaluation systems are essential to identify drought-resistant pepper accessions.In this study,100 pepper accessions were screened for drought resistance under highly controlled conditions at the vegetative stage.Selected accessions exhibited a significantly higher recovery rate after water-deficiency and showed durable resistance under greenhouse conditions.Correlation analysis between drought resistance with morphological and physiological traits showed that the recovery rate was positively correlated with root length and relative water content,and negatively correlated with plant height and leaf area.Gene expression analysis showed that the drought-resistant accession exhibited higher expression levels of drought-responsive genes under drought stress.Among the accessions,anthocyanin-accumulating peppers showed more significant drought resistance compared to other accessions.When the MYB transcription factor An2,the genetic determinant of anthocyanin accumulation,was silenced,drought resistance was significantly reduced.Drought-resistant accessions with favorable adaptive traits identified in this study will be valuable in various breeding programs to generate new pepper cultivars to cope with climate change.
基金The present study was conducted within the framework of the state budget research topic“Development of the scientific principles of creating high-productive varieties of cultivated plants with increased adaptive potential to adverse environmental conditions”No.6541030 funded by the National Academy of Sciences of Ukraine.
文摘Water scarcity severely constrains the genetic potential of wheat yield worldwide.Proline is among the most versatile stress-related metabolites in plants,and targeting genes involved in proline synthesis and degradation represents a promising strategy for developing drought-tolerant wheat genotypes.This study evaluates the performance of the photosynthetic apparatus in transgenic wheat line with RNAi-mediated suppression of proline dehydrogenase(ProDH)and in the original(wild-type)genotype,under both drought and recovery conditions.Drought was induced at the flowering stage by lowering soil moisture to 30%field capacity for 7 days,compared with 70%field capacity in control plants.Measurements were taken at the onset and end of drought period and 7 days after subsequent recovery.The results demonstrated that drought-treated transgenic plants exhibited improved responses to both the short-term and prolonged effects of stress.Relative water content and chlorophyll levels in the leaves of the transgenic plants changed to a significantly lesser extent.The CO2 assimilation rate in the leaves of transgenic plants was significantly higher than in the wild type under both drought stress and recovery.The transgenic plants also showed superior water-use efficiency during photosynthesis under both conditions.While superoxide dismutase and ascorbate peroxidase activities in leaf chloroplasts increased similarly in both genotypes under drought,they returned to control levels more rapidly in the transgenic plants during recovery.Drought-induced productivity reduction was also significantly lower in the transgenic plants.These findings suggest that RNAi-mediated suppression of ProDH improved photosynthetic performance and grain yield in wheat under drought conditions.
基金financially supported by the National Key Research and Development Program of China(2021YFD2200405)the National Natural Science Foundation of China(31930078)special funds for Baotianman Forest Ecosystem Research Station from Chinese Academy of Forestry and Ministry of Science and Technology of China。
文摘Frequent droughts pose considerable threat to global forest carbon uptake,but little is known about the response of forest carbon fluxes in climatic transition zones to seasonal drought.In this study,the responses of carbon fluxes to seasonal drought in two natural forests(Quercus aliena var.acute serrata Maxim and Pinus tabuliformis Carr.)in the Baotianman Nature Reserve were investigated.The Q.aliena forest exhibited a high resilience with stable gross primary productivity(GPP).However,ecosystem respiration(Re)significantly declined by 18.4%compared with normal years,leading to an increase in net carbon sequestration capacity of 4.1%.This resilience was attributed to its deep root system accessing soil water(SWC_(50cm))to sustain stomatal openness,coupled with the efficient utilization of photosynthetically active radiation to drive photosynthesis.In contrast,the P.tabuliformis forest,which relied on shallow soil moisture(SWC_(20cm)),experienced simultaneous decreases in both GPP and Re during drought,with a sharply greater decrease in GPP,resulting in low net carbon sink capacity.Further analysis revealed that the Q.aliena forest prioritized carbon assimilation through a deep water-stomatal synergy strategy(anisohydric behavior),whereas the P.tabuliformis forest adopted an isohydric strategy favoring water conservation at the expense of carbon fixation efficiency.These findings highlight distinct mechanisms underlying drought adaptation between forest types,providing critical insight into optimizing forest carbon cycle models and selecting drought-resistant species under the influence of climate change.
基金supported by the National Key R&D Program of China(2021YFD2200303)the National Natural Science Foundation of China(32271903,U24A20428)。
文摘The formation of wood is affected by the growing season and the environment.Ring-porous tree species have distinct earlywood-latewood differences.However,it is not clear how early wood and latewood respond to drought and the differences in adaptation.Therefore,based on the analyses of phenology,growth,and xylem development over a year,xylem development in Fraxinus mandshurica was divided into earlyw ood,transition,and latewood stages.Variation patterns of 38 wood indices from 31 genotypes indicated that the formation of wood tissues was inhibited,and the proportion of xylem cells was affected by drought at each stage.However,soluble sugar affected osmotic regulation only during drought across early wood and transition stages.To maintain water and nutrient transport during drought and to resist embolism risk,drought in the early wood stage leads to varying degrees of early wood vessel diameter reduction,with pits enlarging to compensate.In contrast,during the late wood stage,drought causes latewood vessel diameter to increase and pits to shrink accordingly.In addition,the results indicate that several wood indices correlate with drought resistance at each stage,but early wood vessel diameter,soluble sugar,and latewood ves sel diameters exhibited the strongest correlations in the early wood,transition,and latewood stages.These findings provide clues to understanding plant survival strategies under drought stress and are of significance for plant ecology research on the growth and adaptation of tree species under climate change.
基金supported by National Key Research and Development Program of China(2022YFF1001600)BeijingNatural Science Foundation(5244040)+1 种基金STI2030-Major Projects(2030ZD0407101)China Postdoctoral Science Foundation(2022M723435)。
文摘Drought stress orchestrates a phosphorylation-dependent signaling cascade that reprograms transcriptional networks to enhance crop resilience.Through a large-scale transgenic screening,we identified ZmCRK5A,a Ca^(2+)-independent calcium-dependent protein kinase(CDPK)-related kinase,as a master regulator of drought tolerance in maize.Mechanistically,ZmCRK5A directly phosphorylates the MYB transcriptional repressor ZmSMH4(Single MYB Histone 4)at three conserved serine residues(Ser42/43/59)within its SANT domain,as demonstrated by in vitro kinase assays and site-directed mutagenesis.This post-translational modification abolishes Zm SMH4's DNA-binding capacity to ACC cis-elements,thereby de-repressing the potassium influx channel gene Zm KCH1(K^(+)Channel 1).Functional validation revealed that Zm KCH1 overexpression confers drought resilience through optimized stomatal dynamics and water retention,whereas clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)-generated zmkch1 mutants display hypersensitivity to water deficit.Crucially,field evaluations demonstrated preserved grain yield alongside enhanced drought tolerance in plants with activated Zm CRK5A-Zm SMH4-Zm KCH1 signaling.Our findings delineate a kinase-transcription factor-ion channel axis that dynamically fine-tunes drought responses while maintaining productivity,providing a strategic framework for engineering stress-adapted crops without yield penalties.
基金supported by the National Natural Science Foundation of China(No.42277481,42007410,32271667,42207537)。
文摘Non-structural carbohydrates(NSCs)are critical for plant drought adaptation,but their environmental drivers under prolonged drought remains unclear.We investigated seasonal NSCs dynamics in the leaf,stem and root of Picea crass ifolia(Qinghai spruce)during the growing seasons of2021-2023 under intensifying drought at three altitudes in Qilian Mountains,Northwest China.Our results revealed synchronous seasonal patterns in soluble sugar,starch,and total non-structural carbohydrate within the same year,contrasting with marked altitudinal disparities.As drought progressed(from 2021 to 2023),soluble sugars initially increased(2022)then declined(2023),while starch showed consistent reduction(except leaves).Moreover,the altitude of peak NSCs concentrations shifted from 3200 m in 2021to 2700 m in 2023.In particular,prolonged drought alters the environmental factors affecting NSCs.NSCs demonstrated significant positive correlations with soil temperature during humid 2021,then negatively with air temperature,vapor pressure deficit,and precipitation during 2022's initial drought,whereas under 2023's persistent drought conditions,soil temperature and water content emerged as dominant drivers.Concurrently,the ratio of soluble sugar to starch transitioned from air temperature and precipitation associations(2021-2022)to soil parameter dependence in2023.These findings provide new insights into the seasonal carbon dynamics of Qinghai spruce and the environmental response mechanisms under increasing drought stress,contributing to a better understanding of tree physiological adaptations in drought stress.
基金supported by the Rural Revitalization Tea Industry Technical Service Project of Fujian Agriculture and Forestry University(Grant No.11899170145)the“Double firstclass”scientific and technological innovation capacity and enhancement cultivation plan of Fujian Agriculture and Forestry University(Grant No.KSYLP004)+4 种基金6.18 Tea Industry Technology Branch of Collaborative Innovation Institute(Grant No.K1520001A)Fujian Agriculture and Forestry University Construction Project for Technological Innovation and Service System of Tea Industry Chain(Grant No.K1520005A01)Tea Industry Branch of Collaborative Innovation Institute of Fujian Agriculture and Forestry University(Grant No.K1521015A)Science and Technology Innovation Special Fund Project of Fujian Agriculture and Forestry University(Grant No.KFb22020XA)the Special Fund for Science and Technology Innovation of Fujian Zhang Tianfu Tea Development Foundation(Grant No.FJZTF01).
文摘Drought stress is a serious natural challenge for tea plants that significantly affects tea yield and quality.miR171s play critical roles in plant stress responses,however,their role in drought stress tolerance in tea plants(Camellia sinensis)is poorly understood.This study experimentally verified the expression patterns of csn-miR171b-3p_2 and its target,scarecrow-like(SCL).We found that csn-miR171b-3p_2 could target and regulate CsSCL6-4 to play an important role in the defense against drought stress in tea plants.CsSCL6-4 is located in the nucleus and is selfactivated in vivo.In addition,we obtained 819 putative binding regions of CsSCL6-4 using DNA affinity purification sequencing analysis,which were assigned to 786 different genes,four of which were drought-resistant genes(CsPrx,CsSDR,CsFAD7,and CsCER1).Yeast one-hybrid and dual-luciferase reporter assays revealed that CsSCL6-4 directly promoted the expression of these four drought resistance genes by binding motifs 1/2/3 in their promoter regions.Both overexpression and suppression of CsSCL6-4 proved that CsSCL6-4 participated in the defense against drought stress in tea plants by regulating the expression of CsPrx,CsSDR,CsFAD7,and CsCER1.In addition,suppression of csn-miR171b-3p_2 expression significantly increased the expression of CsSCL6-4 and activated CsSCL6-4-bound gene transcription under drought stress.Therefore,the csn-miR171b-3p_2-CsSCL6-4 module participates in tea plant resistance to drought stress by promoting the expression of drought resistance genes.Our results revealed the function of csn-miR171b-3p_2 in tea plants and provided new insights into the mechanism of tea plant resistance to drought stress.
基金supported by the National Natural Science Foundation of China(Grant Nos.32102311 and 32102338)the China Postdoctoral Science Foundation(Grant No.2021M690129).
文摘Drought stress significantly impedes apple growth,development,and yield,leading to substantial economic losses within the global apple industry.Malus prunifolia(Mp),a commonly utilized apple rootstock,has shown promise in augmenting cultivated apple resistance to abiotic stress.Although Alfin-like(ALs)proteins have demonstrated pivotal roles in dicotyledonous plants'response to abiotic stresses,knowledge about AL genes in apple rootstocks is limited,and their functions remain largely elusive.In this study,we identified and characterized 10 MpAL gene members in the apple rootstock genome,confirming their localization within the nucleus.Our investigation revealed the significant regulation of MpALs'expression under drought and abscisic acid(ABA)stresses in M.prunifolia.In this study,one of the members,MpAL1,was selected for further exploration in Arabidopsis and apple to explore its potential function in response to drought and ABA stresses.The results showed that overexpression-MpAL1 transgenic apple calli grew significantly better than WT and MpAL1-RNAi lines,which regulates the accumulation of H_(2)O_(2)and O_(2).-levels.Additionally,transgenic Arabidopsis plants overexpressing MpAL1 exhibited positively regulating antioxidant enzymes activities under stress treatments.Further study showed that silencing MpAL1 in apple plants showed obvious chlorosis in leaves,and accumulation of reactive oxygen species under drought stress.Moreover,our detailed analysis established that MpAL1 regulates several drought and ABA-responsive genes,exerting an influence on their expression in transgenic apple.Collectively,our findings identify MpAL1 as a positive regulator that increases drought stress in apple,shedding light on its potential significance in bolstering drought resistance in this fruit crop.
基金funded by the Inner Mongolia Autonomous Region Natural Science Foundation Youth Fund Project(Grants No.2024QN04020)A Science and technology program of Inner Mongolia Autonomous Region(Grants No.2022YFDZ0027)。
文摘Flash droughts(FDs)develop quickly and can rapidly deplete soil moisture,posing significant threats to agriculture and pastoral systems.To investigate the spatiotemporal characteristics and development mechanisms of FDs in Inner Mongolia,China,and to assess the roles of key meteorological drivers in driving soil moisture variability,FD events were identified using root-zone soil moisture data during the growing seasons from 1982 to 2022.The results indicate the presence of five FD hotspot regions,located in the southern Alxa Plateau,the Hetao Plain in Bayannur,the northwestern Xilingol Plain,the western Liaohe River Plain,and the northern Da Hinggan Ling.Over 41 years,FDs occurred on average 7.44 events across the study area,with a mean duration of 9.17 pentads(1 pentad equals 5 days).The duration exhibited a significant increasing trend of 0.39 pentads/10 years.FD onsets primarily lasted for 2-3 pentads.During the FD development phase,precipitation and evapotranspiration decreased while temperature,potential evapotranspiration,incoming solar radiation,and vapor pressure deficit increased.The dominant meteorological drivers of FD development exhibited notable spatial heterogeneity across hotspot regions,and vapor pressure deficit consistently was the most influential factor.These findings improve the understanding of climate drivers at different stages of FD development and provide scientific support for early warning and prevention of droughts in Inner Mongolia.
基金supported by the National Natural Science Foundation of China(grant no.32371866)。
文摘Drought influences carbon fixation by plants.Therefore,elucidating its impact on carbon fluxes in plants at the ecosystem level is crucial for assessing their role in mitigating climate change.Using carbon fluxes and environmental factor data from FLUXNET sites,we analyzed the influence of drought on carbon fluxes,their drivers,time-lag effects,and recovery times across various climatic regions and seasons.Results showed drought significantly decreased gross primary production(GPP),ecosystem respiration,and net ecosystem productivity in arid regions but slightly increased carbon sequestration in humid regions.Summer droughts negatively affected vegetation carbon fluxes,partly offset by the positive impact of spring droughts.Nonforest carbon fluxes were more susceptible to drought effects than forest fluxes.Soil water content(SWC)was the main influence on changes in arid regions,whereas vapor pressure deficit(VPD)dominated humid regions.Decreased SWC and increased VPD reduced carbon sequestration in arid regions but increased it in humid regions.Increased VPD reduced GPP,leading to forest carbon loss,whereas decreased SWC reduced GPP,leading to nonforest carbon loss.The lag time of the drought effects on carbon fluxes was longer in humid regions(19.44 d)than in arid regions(14.71 d).Compared to nonforest areas(16.74 d and 57 d for drought lag and recovery time,respectively),forest areas had a longer lag(18.81 d)and recovery time(92 d).The findings revealed discrepancies in the main factors regulating vegetation carbon fluxes during droughts between arid and humid regions and between forest and nonforest ecosystems.These insights provide a new perspective on understanding and simulating carbon-climate feedback.Enhancing ecosystem diversity is a feasible measure to increase drought resistance.
基金supported by the National Key Research and Development Project of China(2025YFE0103300)the National Natural Science Foundation of China(W2412135)+2 种基金the Natural Science Foundation of Xinjiang Uygur Autonomous Region(2024D01A143,2025D01B165)the China Postdoctoral Science Foundation(GZC20250226)the S&T Innovation and Development Project of Information Institution of Ministry of Emergency Management,China(2024506).
文摘Tajikistan,a mountainous country and a vital water tower for Central Asia,is becoming increasingly vulnerable to snow drought under climate change,threatening its snow-and glacier-fed streamflow.Yet,the impacts of snow drought on the regional hydrology remain insufficiently understood.In this study,we integrated multisource data,including the Fifth Generation European Centre for Medium-Range Weather Forecasts Atmospheric Reanalysis for Land Applications(ERA5-Land)data and hydrological station data,to systematically assess the snow drought patterns and their impacts on streamflow during 1950–2023.We identified snow drought events based on precipitation and snow fraction anomalies relative to climatological means and classified them into warm snow drought,dry snow drought,and warm&dry snow drought.The results revealed that snow drought was a recurrent phenomenon,occurring in 51.70%of the years during the study period,with warm&dry snow drought accounting for 21.90%of the total events.Both the frequency and severity exhibited pronounced spatial variability,largely governed by the elevation and snowfall fraction.Specifically,the frequency of warm snow drought was negatively correlated with the snowfall fraction,decreasing on average by 0.20 per unit increase in snowfall fraction,whereas the frequency of dry snow drought was positively correlated,increasing by 0.07 per unit increase.The streamflow analysis results demonstrated that snow drought typically reduced the warm-season discharge by 5.00%–18.00%in certain rivers,thereby exacerbating the water stress during the dry season.The results of this study advance our understanding by explicitly linking the types of snow drought to hydrological responses in Central Asia’s high mountains,providing a scientific basis for climate adaptation and sustainable water resource management in Tajikistan.
基金supported by the National Key Research and Development Program of China(No.2021YFD2200402)the Leading Goose Project from Zhejiang Department of Science and Technology(No.2023C02035)+1 种基金the Central Non-profit Research Institution(CAFYBB2025ZC006)the Fundamental Research Funds for the National Natural Science Foundation of China(No.32071756 and U24A20429)。
文摘Forest ecosystems are increasingly susceptible to droughts and nitrogen(N)deposition.However,the effects of N addition on the growth of bamboo under drought stress remain unclear.This study conducted a comprehensive factorial experiment to investigate the combined effects of drought and N addition on the growth of Moso bamboo(Phyllostachys edulis)seedlings.Six treatment combinations were established:0 mg·kg^(-1) N with 80%–85%field capacity(FC)soil moisture,0 mg·kg^(-1) N with 50%–55%FC,0 mg·kg^(-1) N with 30%–35%FC,100 mg·kg^(-1) N with 80%–85%FC,100 mg·kg^(-1) N with 50%–55%FC,and 100 mg·kg^(-1) N with 30%–35%FC.The results revealed that drought altered the soil microbial community structure and significantly reduced the biomass of Moso bamboo seedlings.Notably,N addition mitigated the adverse effects of drought on bamboo growth in general.Specifically,N addition alleviated the negative effects of drought on root biomass but aggravated them on leaf biomass of Moso bamboo seedlings,and with the intensification of drought stress,this effect was weakened.Furthermore,sucrose and urease exerted dominant and direct influences on the total biomass.The results underscore the pivotal role of N in facilitating plant drought tolerance,suggesting that the interplay between drought and N addition in plant growth should be considered in the context of changing environmental conditions,and offering novel perspectives on sustainable management strategies for bamboo forests.
基金Under the auspices of the National Key Research and Development Program of China Science and Technology Cooperation Project of the Chinese and Russian Governments(No.2023YFE0111300)National Social Science Fund of China(No.23BGL204)Natural Science Foundation of Inner Mongolia(No.2022MS04001)。
文摘Prolonged droughts have emerged as a major impediment to the revitalization of pastoral regions worldwide because they significantly augment their susceptibility to the deleterious effects of global climate change,overgrazing,and land degradation.This study,conducted in 106 pastoral villages across 33 pastoral banners of Inner Mongolia Autonomous Region of China between August 2021 and October 2022,used a community resilience evaluation indicator system to assess drought resistance.By calculating a community resilience index,the research explored influencing factors and proposed countermeasures,aiming to enhance resilience to prolonged drought.The results revealed three key findings.1)Pastoral areas exhibited a limited degree of community resilience to drought disasters(overall score=0.28),with resilience levels forming a pyramid-shaped hierarchy.2)Dimensional analysis showed that resilience scores decreased sequentially across five domains:social(0.53)>cultural(0.44)>environmental(0.38)>economic(0.32)>management(0.27).These results highlight the crucial role of economic and management resilience in enhancing community resilience,particularly when accompanied by pre-and post-disaster government support and social security,both of which must be improved.3)Key factors influencing community resilience included geographical location,traffic accessibility,and frequency and severity of droughts.From a drought resilience perspective,targeted strategies and recommendations are proposed to provide novel and practical approaches for achieving sustainable development in pastoral areas and rural regions as a whole.
文摘As part of my master’s programme in resource use and environmental science at China Agricultural University,I had the privilege of joining a study trip to the Shiyang River Basin and its surrounding areas from 17 to 21 July 2025.This trip to Gansu Province was organised under the China-Africa Joint Centre for Agricultural Demonstration and Training in Arid Regions programme,an initiative aligned with President Xi Jinping’s call for deeper China-Africa cooperation.
基金Under the auspices of the Third Xinjiang Scientific Expedition Program(No.2022xjkk0600)。
文摘The Yili River Basin in Northwest China is a crucial ecological security barrier,yet it faces frequent droughts amid global climate change,posing significant threats to food security and ecological stability.However,the spatiotemporal variations and driving mechanisms of drought in the basin remain unclear.Based on the monthly Standardized Precipitation Evapotranspiration Index(SPEI),this study employed the Run-Length theory to identify drought events in the basin during 1980-2020,applied statistical and time-series analyses to investigate the spatiotemporal variations,trends,periodicity,and persistence of drought,and explored the underlying drivers associated with meteorological factors and large-scale atmospheric circulation patterns.The results showed that droughts in the Yili River Basin are more severe in spring and summer.Droughts in the central and southwestern regions exhibit greater severity,with shorter durations and stronger intensity.Drought conditions have generally worsened(Sen’s slope=−0.146/10 yr),with notable intensification since 2005,especially in the northwestern region.Spring droughts(Sen’s slope=−0.213/10 yr)and summer droughts(Sen’s slope=−0.169/10 yr)have intensified at most stations,while autumn and winter droughts have eased.In the future,droughts are expected to alleviate overall,but summer droughts may continue to intensify.The Yili River Basin exhibits two primary drought periods of 9 yr and 21 yr,with primary periods in autumn(20 yr)and winter(20 yr)being longer than those in spring(10 yr)and summer(17 yr).Finally,droughts are impacted by both meteorological factors and large-scale atmospheric circulation patterns.Rising temperatures and uneven precipitation have intensified droughts.The SPEI exhibits a co-phase relationship with the North Atlantic Oscillation and an antiphase relationship with the East Central Tropical Pacific Sea Surface Temperature.Therefore,close monitoring and mitigation are necessary for spring and summer droughts,with a focus on the central and southwestern areas in autumn and winter.
基金supported by the National Key Research and Development Program of China(Grant No.2023YFC3006505)the Fundamental Research Funds for the Central Universities of China(Grant No.B240203007)the National Key Laboratory of Water Disaster Prevention(Grant No.524015222)。
文摘Understanding the evolution and lag effects of droughts is critical to effective drought warning and water resources management.However,due to limited hydrological data,few studies have examined hydrological droughts and their lag time from meteorological droughts at a daily scale.In this study,precipitation data were collected to calculate the standardized precipitation index(SPI),and runoff data simulated by the variable infiltration capacity(VIC)model were utilized to compute the standardized runoff index(SRI).The three-threshold run theory was used to identify drought characteristics in China.These drought characteristics were utilized to investigate spatiotemporal variations,seasonal trends,and temporal changes in areas affected by meteorological and hydrological droughts.Additionally,the interconnections and lag effects between meteorological and hydrological droughts were explored.The results indicated that(1)drought occurred during approximately 28%of the past 34 years in China;(2)drought conditions tended to worsen in autumn and weaken in winter;(3)drought-affected areas shifted from northwest to northeast and finally to southern China;and(4)the correlation between meteorological and hydrological droughts was lower in the northwest and higher in the southeast,with all correlation coefficients exceeding 0.7.The lag times between meteorological and hydrological droughts were longest(5 d)in the Yangtze River,Yellow River,and Hai River basins,and shortest(0 d)in the Tarim River Basin.This study provides a scientific basis for effective early warning of droughts.
基金supported by the National Natural Science Foundation of China(Grant No.42471027).
文摘Accurate drought assessment demands thoughtful consideration of drought definition first of all.Drought is commonly defined as a prolonged period of below-average precipitation leading to water shortages that impact ecosystems,agriculture,and human societies.However,meteorologists,hydrologists,and agronomists often use different criteria to define drought,depending on their specific focus areas.For example,hydrologists define drought according to water deficits in some components of the hydrological cycle(such as precipitation,soil moisture,river flow,and groundwater)or its impacts on the level of services provided to public water supply,irrigation,or hydropower demands(Tate and Gustard,2000).Differences in drought definitions may result in great uncertainties in drought assessment(Satoh et al.,2021).We cannot expect the existence of any workable generalized objective definition of drought(Lloyd-Hughes,2014).
基金supported by the projects of the National Key Research and Development Program of China(2023YFD2300202)the Natural Science Foundation of Jiangsu Province,China(BK20241543)+5 种基金the National Natural Science Foundation of China(32272213,32030076,U1803235,and 32021004)the Fundamental Research Funds for the Central Universities,China(XUEKEN2023013)the Jiangsu Innovation Support Program for International Science and Technology Cooperation Project,China(BZ2023049)the Jiangsu Agriculture Science and Technology Innovation Fund,China(CX(22)1006)the China Agriculture Research System(CARS-03)the Jiangsu Collaborative Innovation Center for Modern Crop Production,China(JCIC-MCP)。
文摘Frequent drought events severely restrict global crop productivity,especially those occurring in the reproductive stages.Moderate drought priming during the earlier growth stages is a promising strategy for allowing plants to resist recurrent severe drought stress.However,the underlying mechanisms remain unclear.Here,we subjected wheat plants to drought priming during the vegetative growth stage and to severe drought stress at 10 days after anthesis.We then collected leaf samples at the ends of the drought priming and recovery periods,and at the end of drought stress for transcriptome sequencing in combination with phenotypic and physiological analyses.The drought-primed wheat plants maintained a lower plant temperature,with higher stomatal openness and photosynthesis,thereby resulting in much lower 1,000-grain weight and grain yield losses under the later drought stress than the non-primed plants.Interestingly,416 genes,including 27 transcription factors(e.g.,MYB,NAC,HSF),seemed to be closely related to the improved drought tolerance as indicated by the dynamic transcriptome analysis.Moreover,the candidate genes showed six temporal expression patterns and were significantly enriched in several stress response related pathways,such as plant hormone signal transduction,starch and sucrose metabolism,arginine and proline metabolism,inositol phosphate metabolism,and wax synthesis.These findings provide new insights into the physiological and molecular mechanisms of the long-term effects of early drought priming that can effectively improve drought tolerance in wheat,and may provide potential approaches for addressing the challenges of increasing abiotic stresses and securing food safety under global warming scenarios.
基金the China National Key R&D Program(Grant No.2019YFA0606900)the National Science Founda-tion of China(Grant No.41771536)the National Science Founda-tion for Distinguished Young Scholars of China(Grant No.51425903)。
文摘Global warming and rapid economic development have led to increased levels of disaster risk in China.Previous attempts at assessing drought risk were highly subjective in terms of assessment methods and selection of the assessment indicators and which resulted in appreciable uncertainty in the results of these risk assessments.Based on the assumption that areas with historically high drought losses are more likely to suffer future high drought losses,we develop a new drought risk assessment model that includes historical drought loss data.With this model,we map the regional differentiation of Chinese drought risk.Regions with high(extreme high)drought risk account for 4.3%of China’s area.Five significant high-risk areas have been identified:Northeast China,North China,the east part of Northwest China,the east part of Southwest China and a small part in the west of Northwest China.Areas with high and extreme high drought risk are dominant in the Heilongjiang Province,accounting for 32%of the total area,followed by the Ningxia Hui Autonomous Region,with 26%of total area.The contribution of each influencing factor has been quantified,which indicates that high-exposure and high-vulnerability account for the high-risk of drought.We recommend that measures like strengthening the protection of cultivated land and reducing dependence on the primary industry should be taken to mitigate to drought-induced losses.
