Red clay landslides are widely distributed worldwide,resulting in severe loss of life and property.Although rainfall-induced red clay slopes have received extensive attention,the role of cracks in the evolutionary pro...Red clay landslides are widely distributed worldwide,resulting in severe loss of life and property.Although rainfall-induced red clay slopes have received extensive attention,the role of cracks in the evolutionary process of red clay slopes and their connection to failure mechanisms is still poorly understood.A comprehensive approach integrating field investigation,laboratory tests,and numerical simulations was conducted to study the 168 red clay landslides in Xinshao County,China.The results show that red clay is prone to forming cracks at high moisture content due to its low swelling and high shrinkage properties.The failure mode of red clay slopes can be summarized in three stages:crack generation,slope excavation,and slope failure.Furthermore,the retrospective analysis and numerical simulations of the typical landslide in Guanchong indicated that intense rainfall primarily impacts the shallow layer of soil within approximately 0.5 m on the intact slope.However,cracks change the pattern of rainfall infiltration in the slope.Rainwater infiltrates rapidly through the preferential channels induced by the cracks rather than uniformly and slowly from the slope surface.This results in a significant increase in both the depth of infiltration and the saturated zone area of the cracked slope,reaching 3.8 m and 36.2 m^(2),respectively.Consequently,the factor of safety of the slope decreases by 13.4%compared to the intact slope,ultimately triggering landslides.This study can provide valuable insights into understanding the failure mechanisms of red clay slopes in China and other regions with similar geological settings.展开更多
China’s low-carbon development path will make significant contributions to achieving global sustainable development goals.Due to the diverse natural and economic conditions across different regions in China,there exi...China’s low-carbon development path will make significant contributions to achieving global sustainable development goals.Due to the diverse natural and economic conditions across different regions in China,there exists an imbalance in the distribution of car-bon emissions.Therefore,regional cooperation serves as an effective means to attain low-carbon development.This study examined the pattern of carbon emissions and proposed a potential joint emission reduction strategy by utilizing the industrial carbon emission intens-ity(ICEI)as a crucial factor.We utilized social network analysis and Local Indicators of Spatial Association(LISA)space-time trans-ition matrix to investigate the spatiotemporal connections and discrepancies of ICEI in the cities of the Pearl River Basin(PRB),China from 2010 to 2020.The primary drivers of the ICEI were determined through geographical detectors and multi-scale geographically weighted regression.The results were as follows:1)the overall ICEI in the Pearl River Basin is showing a downward trend,and there is a significant spatial imbalance.2)There are numerous network connections between cities regarding the ICEI,but the network structure is relatively fragile and unstable.3)Economically developed cities such as Guangzhou,Foshan,and Dongguan are in the center of the network while playing an intermediary role.4)Energy consumption,industrialization,per capita GDP,urbanization,science and techno-logy,and productivity are found to be the most influential variables in the spatial differentiation of ICEI,and their combination in-creased the explanatory power of the geographic variation of ICEI.Finally,through the analysis of differences and connections in urban carbon emissions under different economic levels and ICEI,the study suggests joint carbon reduction strategies,which are centered on carbon transfer,financial support,and technological assistance among cities.展开更多
Long-term temperature variations inferred from high-resolution proxies provide an important context to evaluate the intensity of current warming.However,tem-perature reconstructions in humid southeastern China are sca...Long-term temperature variations inferred from high-resolution proxies provide an important context to evaluate the intensity of current warming.However,tem-perature reconstructions in humid southeastern China are scarce and particularly lack long-term data,limiting us to obtain a complete picture of regional temperature evolution.In this study,we present a well-verified reconstruction of winter-spring(January–April)minimum temperatures over southeastern China based on stable carbon isotopic(δ^(13)C)records of tree rings from Taxus wallichiana var.mairei from 1860 to 2014.This reconstruction accounted for 56.4%of the total observed variance.Cold periods occurred during the 1860s–1910s and 1960s–1970s.Although temperatures have had an upward trend since the 1920s,most of the cold extremes were in recent decades.The El Niño-Southern Oscillation(ENSO)variance acted as a key modulator of regional winter-spring minimum temperature variability.However,teleconnections between them were a nonlinear process,i.e.,a reduced or enhanced ENSO variance may result in a weakened or intensified temperature-ENSO relationship.展开更多
Employing the nonlinear local Lyapunov exponent (NLLE) technique, this study assesses the quantitative predictability limit of oceanic mesoscale eddy (OME) tracks utilizing three eddy datasets for both annual and seas...Employing the nonlinear local Lyapunov exponent (NLLE) technique, this study assesses the quantitative predictability limit of oceanic mesoscale eddy (OME) tracks utilizing three eddy datasets for both annual and seasonal means. Our findings reveal a discernible predictability limit of approximately 39 days for cyclonic eddies (CEs) and 44 days for anticyclonic eddies (AEs) within the South China Sea (SCS). The predictability limit is related to the OME properties and seasons. The long-lived, large-amplitude, and large-radius OMEs tend to have a higher predictability limit. The predictability limit of AE (CE) tracks is highest in autumn (winter) with 52 (53) days and lowest in spring (summer) with 40 (30) days. The spatial distribution of the predictability limit of OME tracks also has seasonal variations, further finding that the area of higher predictability limits often overlaps with periodic OMEs. Additionally, the predictability limit of periodic OME tracks is about 49 days for both CEs and AEs, which is 5-10 days higher than the mean values. Usually, in the SCS, OMEs characterized by high predictability limit values exhibit more extended and smoother trajectories and often move along the northern slope of the SCS.展开更多
In the context of changes in global climate and land uses,biodiversity patterns and plant species distributions have been significantly affected.Soil salinization is a growing problem,particularly in the arid areas of...In the context of changes in global climate and land uses,biodiversity patterns and plant species distributions have been significantly affected.Soil salinization is a growing problem,particularly in the arid areas of Northwest China.Halophytes are ideal for restoring soil salinization because of their adaptability to salt stress.In this study,we collected the current and future bioclimatic data released by the WorldClim database,along with soil data from the Harmonized World Soil Database(v1.2)and A Big Earth Data Platform for Three Poles.Using the maximum entropy(MaxEnt)model,the potential suitable habitats of six halophytic plant species(Halostachys caspica(Bieb.)C.A.Mey.,Halogeton glomeratus(Bieb.)C.A.Mey.,Kalidium foliatum(Pall.)Moq.,Halocnemum strobilaceum(Pall.)Bieb.,Salicornia europaea L.,and Suaeda salsa(L.)Pall.)were assessed under the current climate conditions(average for 1970-2000)and future(2050s,2070s,and 2090s)climate scenarios(SSP245 and SSP585,where SSP is the Shared Socio-economic Pathway).The results revealed that all six halophytic plant species exhibited the area under the receiver operating characteristic curve values higher than 0.80 based on the MaxEnt model,indicating the excellent performance of the MaxEnt model.The suitability of the six halophytic plant species significantly varied across regions in the arid areas of Northwest China.Under different future climate change scenarios,the suitable habitat areas for the six halophytic plant species are expected to increase or decrease to varying degrees.As global warming progresses,the suitable habitat areas of K.foliatum,S.salsa,and H.strobilaceum exhibited an increasing trend.In contrast,the suitable habitat areas of H.glomeratus,S.europaea,and H.caspica showed an opposite trend.Furthermore,considering the ongoing global warming trend,the centroids of the suitable habitat areas for various halophytic plant species would migrate to different degrees,and four halophytic plant species,namely,S.salsa,H.strobilaceum,H.glomeratus,and H.capsica,would migrate to higher latitudes.Temperature,precipitation,and soil factors affected the possible distribution ranges of these six halophytic plant species.Among them,precipitation seasonality(coefficient of variation),precipitation of the warmest quarter,mean temperature of the warmest quarter,and exchangeable Na+significantly affected the distribution of halophytic plant species.Our findings are critical to comprehending and predicting the impact of climate change on ecosystems.The findings of this study hold significant theoretical and practical implications for the management of soil salinization and for the utilization,protection,and management of halophytes in the arid areas of Northwest China.展开更多
Terrestrial carbon storage(CS)plays a crucial role in achieving carbon balance and mitigating global climate change.This study employs the Shared Socioeconomic Pathways and Representative Concentration Pathways(SSPs-R...Terrestrial carbon storage(CS)plays a crucial role in achieving carbon balance and mitigating global climate change.This study employs the Shared Socioeconomic Pathways and Representative Concentration Pathways(SSPs-RCPs)published by the Intergovernmental Panel on Climate Change(IPCC)and incorporates the Policy Control Scenario(PCS)regulated by China’s land management policies.The Future Land Use Simulation(FLUS)model is employed to generate a 1 km resolution land use/cover change(LUCC)dataset for China in 2030 and 2060.Based on the carbon density dataset of China’s terrestrial ecosystems,the study analyses CS changes and their relationship with land use changes spanning from 1990 to 2060.The findings indicate that the quantitative changes in land use in China from 1990 to 2020 are characterised by a reduction in the area proportion of cropland and grassland,along with an increase in the impervious surface and forest area.This changing trend is projected to continue under the PCS from 2020 to 2060.Under the SSPs-RCPs scenario,the proportion of cropland and impervious surface predominantly increases,while the proportions of forest and grassland continuously decrease.Carbon loss in China’s carbon storage from 1990 to 2020 amounted to 0.53×10^(12)kg,primarily due to the reduced area of cropland and grassland.In the SSPs-RCPs scenario,more significant carbon loss occurs,reaching a peak of8.07×10^(12)kg in the SSP4-RCP3.4 scenario.Carbon loss is mainly concentrated in the southeastern coastal area and the Beijing-TianjinHebei(BTH)region of China,with urbanisation and deforestation identified as the primary drivers.In the future,it is advisable to enhance the protection of forests and grassland while stabilising cropland areas and improving the intensity of urban land.These research findings offer valuable data support for China’s land management policy,land space optimisation,and the achievement of dual-carbon targets.展开更多
China has resolved its overall regional poverty in 2020 by attaining moderate societal prosperity.The country has entered a new development stage designed to achieve its second centenary goal.However,ecological fragil...China has resolved its overall regional poverty in 2020 by attaining moderate societal prosperity.The country has entered a new development stage designed to achieve its second centenary goal.However,ecological fragility and risk susceptibility have increased the risk of returning to ecological poverty.In this paper,the Liupan Mountain Region of China was used as a case study,and the counties were used as the scale to reveal the spatiotempora differentiation and influcing factors of the risk of returning to poverty in study area.The indicator data for returning to ecological poverty from 2011-2020 were collected and summarized in three dimensions:ecological,economic and social.The autoregressive integrated moving average model(ARIMA)time series and exponential smoothing method(ES)were used to predict the multidimensional indicators of returning to ecological poverty for 61 counties(districts)in the Liupan Mountain Region for 2021-2030.The back propagation neural network(BPNN)and geographic information system(GIS)were used to generate the spatial distribution and time variation for the index of the risk of returning to ecological poverty(RREP index).The results show that 1)ecological factors were the main factors in the risk of returning to ecological poverty in Liupan Mountain Region.2)The RREP index for the 61 counties(districts)exhibited a downward trend from 2021-2030.The RREP index declined more in medium-and high-risk areas than in low-risk areas.From 2021 to 2025,the RREP index exhibited a slight downward trend.From 2026 to2030,the RREP index was expected to decline faster,especially from 2029-2030.3)Based on the RREP index,it can be roughly divided into three types,namely,the high-risk areas,the medium-risk areas,and the low-risk areas.The natural resource conditions in lowrisk areas of returning to ecological poverty,were better than those in medium-and high-risk areas.展开更多
China has experienced rapid rural transformation in the past four decades.Accompanying the rapid transformation is a significant rise in rural household income and a substantial fall in rural poverty.This paper examin...China has experienced rapid rural transformation in the past four decades.Accompanying the rapid transformation is a significant rise in rural household income and a substantial fall in rural poverty.This paper examines the evolutions of and the relationships between rural transformation(high-value agriculture and rural non-farm employment)and its outcomes(per capita rural income and rural poverty incidence)using provincial-level data.The results show that 31 provinces/autonomous regions/municipalities have undergone significant rural transformation,but the level and speed of rural transformation differed considerably.Moreover,an increased level of rural transformation is often associated with higher per capita rural income and reduced rural poverty incidence.Notably,a category of provincial rural transformation based on high-value agriculture and rural non-farm employment is also analyzed.We further discuss the likely impacts of institutions,policies,and investments(IPIs)on rural transformation and conclude with policy implications.展开更多
Extreme high temperatures frequently occur in southwestern China,significantly impacting the local ecological system and economic development.However,accurate prediction of extreme high-temperature days(EHDs)in this r...Extreme high temperatures frequently occur in southwestern China,significantly impacting the local ecological system and economic development.However,accurate prediction of extreme high-temperature days(EHDs)in this region is still an unresolved challenge.Based on the spatiotemporal characteristics of EHDs over China,a domain-averaged EHD index over southwestern China(SWC-EHDs)during April-May is defined.The simultaneous dynamic and thermodynamic fields associated with the increased SWC-EHDs are a local upper-level anticyclonic(high-pressure)anomaly and wavy geopotential height anomaly patterns over Eurasia.In tracing the origins of the lower boundary anomalies,two physically meaningful precursors are detected for SWC-EHDs.They are the tripolar SST change tendency from December-January to February-March in the northern Atlantic and the February-March mean snow depth in central Asia.Using these two selected predictors,a physics-based empirical model prediction was applied to the training period of 1961–2005 to obtain a skillful prediction of the EHDs index,attaining a correlation coefficient of 0.76 in the independent prediction period(2006–19),suggesting that 58%of the total SWC-EHDs variability is predictable.This study provides an estimate for the lower bound of the seasonal predictability of EHDs as well as for the hydrological drought over southwestern China.展开更多
Seasonal prediction of summer precipitation over eastern China is closely linked to the East Asian monsoon circulation,which is largely affected by the El Niño-Southern Oscillation(ENSO).In this study,results sho...Seasonal prediction of summer precipitation over eastern China is closely linked to the East Asian monsoon circulation,which is largely affected by the El Niño-Southern Oscillation(ENSO).In this study,results show that spring soil moisture(SM)over the Indo-China peninsula(ICP)could be a reliable seasonal predictor for eastern China summer precipitation under non-ENSO conditions.When springtime SM anomalies are present over the ICP,they trigger a structured response in summertime precipitation over most of eastern China.The resultant south-to-north,tri-polar configuration of precipitation anomalies has a tendency to yield increased(decreased)precipitation in the Yangtze River basin and decreased(increased)in South and North China with a drier(wetter)spring soil condition in the ICP.The analyses show that ENSO exerts a powerful control on the East Asian circulation system in the ENSO-decaying summer.In the case of ENSO forcing,the seasonal predictability of the ICP spring SM for eastern China summer precipitation is suppressed.However,in the absence of the influence of ENSO sea surface temperature anomalies from the preceding winter,the SM anomalies over the ICP induce abnormal local heating and a consequent geopotential height response owing to its sustained control on local temperature,which could,in turn,lead to abnormal eastern China summer precipitation by affecting the East Asian summer monsoon circulation.The present findings provide a better understanding of the complexity of summer climate predictability over eastern China,which is of potential significance for improving the livelihood of the people.展开更多
The prediction of precipitation at subseasonal to seasonal(S2S)timescales remains an enormous challenge because of the gap between weather and climate predictions.This study compares three deep learning algorithms,nam...The prediction of precipitation at subseasonal to seasonal(S2S)timescales remains an enormous challenge because of the gap between weather and climate predictions.This study compares three deep learning algorithms,namely,the long short-term memory recurrent(LSTM),gated recurrent unit(GRU),and recurrent neural network(RNN),and selects the optimal algorithm to establish an S2S precipitation prediction model.The models were evaluated in four subregions of the Sichuan Province:the Plateau,Valley,eastern Basin,and western Basin.The results showed that the RNN model had better performance than the LSTM and GRU models.This could be because the RNN model had an advantage over the LSTM model in the transformation of climate indices with positive and negative variations.In the validation of test datasets,the RNN model successfully predicted the precipitation trend in most years during the wet season(May-October).The RNN model had a lower prediction bias(within±10%),higher sign accuracy of the precipitation trend(~88.95%),and greater accuracy of the maximum precipitation month(>0.85).For the prediction of different lead times,the RNN model was able to provide a stable trend prediction for summer precipitation,and the time correlation coefficient score was higher than that of the National Climate Center of China.Furthermore,this study proposed a method to measure the sensitivity of the RNN model to different input features,which may provide unprecedented insights into the nonlinear relationship and complicated feedback process among climate systems.The results of the sensitivity distribution are as follows.First,the Niño 4 and Niño 3.4 indices were equally important for the prediction of wet season precipitation.Second,the sensitivity of the snow cover on the Tibetan Plateau was higher than that in the Northern Hemisphere.Third,an opposite sensitivity appeared in two different patterns of the Indian Ocean and sea ice concentrations in the Arctic and the Barents Sea.展开更多
Red blood cell(RBC)aggregation as well as their deformation signi¯cantly affects blood microrheology.These processes depend on various factors,one of which is concentration of the nitric oxide,one of the main sig...Red blood cell(RBC)aggregation as well as their deformation signi¯cantly affects blood microrheology.These processes depend on various factors,one of which is concentration of the nitric oxide,one of the main signaling molecule in the bloodstream.The purpose of this study was to investigate the effect of nitric oxide on the microrheological properties of red blood cells(RBCs)in RBC samples of various media after the addition of nitric oxide donor sodium nitroprusside in vitro.Microrheological properties were measured using laser aggregometer and ektacytometer based on diffuse light scattering and diffraction of laser light on a suspension of RBCs,respectively.The study found that heparin-stabilized blood showed increased RBC aggregation and deformation with sodium nitroprusside concentrations of 100,and 200M,while EDTA-stabilized blood showed slightly decreased aggregation and unchanged deformation.With washed RBCs in dextran solution,the addition of sodium nitroprusside(in the concentrations of 100,and 200M)resulted in decreased aggregation and increased deformation.These-ndings aid in our understanding of nitric oxide's effect on RBC microrheological properties.展开更多
The impact of cyclodextrins(CDs)on wine quality and stability remains largely unknown.This study systematically assessed the protective effect of the post-fermentation addition of CDs on color stability of red wine fr...The impact of cyclodextrins(CDs)on wine quality and stability remains largely unknown.This study systematically assessed the protective effect of the post-fermentation addition of CDs on color stability of red wine from the viewpoints of color characteristics,copigmentation and phenolic profiles.The grey relational analysis(GRA)and principal component analysis(PCA)methods were employed to dissect the key effective determinants related to color quality.The addition of CDs induced a significant hyperchromic effect of 8.19-25.40%,a significant bathochromic effect and an enhancement of the color intensity.Furthermore,the evolution of anthocyanin forms and the content of monomeric anthocyanins revealed that β-CD is a superior favorable cofactor during wine aging,but for long-term aging,2-HP-β-CD and 2-HP-γ-CD are more beneficial in promoting the formation of polymerized anthocyanins and color stability.This work provides an important reference for the use of CDs to enhance the color quality and stability of red wines.展开更多
A more resilient livelihood is increasingly recognized as an efficient way to improve vulnerable households’food security and optimize their dietary decisions.This study quantifies rural household resilience in weste...A more resilient livelihood is increasingly recognized as an efficient way to improve vulnerable households’food security and optimize their dietary decisions.This study quantifies rural household resilience in western China,identifies the three pillars(absorptive capacity,adaptive capacity,and transformative capacity)contribution to resilience,and then establishes the estimated Resilience Capacity Index(RCI)linked with food security and dietary diversity supported by the multiple indicator multiple cause(MIMIC)model.Results show that,despite geographical heterogeneity,the RCI consistently increased from 2015 to 2021.Households with a higher RCI inheriting better capacity to deal with risk and shocks are significantly and positively correlated with increasing food expenditure and diversifying food choices.It can be because resilient households will allocate more money to food expenditure instead of saving for livelihood uncertainty.Thus,policymakers can provide more incentives for rural households to adopt more dynamic and effective risk management strategies.This,in turn,could yield positive spillover effects by preventing human capital loss associated with dietary-related chronic diseases and mortality.展开更多
Traumatic spinal cord injury is potentially catastrophic and can lead to permanent disability or even death.China has the largest population of patients with traumatic spinal cord injury.Previous studies of traumatic ...Traumatic spinal cord injury is potentially catastrophic and can lead to permanent disability or even death.China has the largest population of patients with traumatic spinal cord injury.Previous studies of traumatic spinal cord injury in China have mostly been regional in scope;national-level studies have been rare.To the best of our knowledge,no national-level study of treatment status and economic burden has been performed.This retrospective study aimed to examine the epidemiological and clinical features,treatment status,and economic burden of traumatic spinal cord injury in China at the national level.We included 13,465 traumatic spinal cord injury patients who were injured between January 2013 and December 2018 and treated in 30 hospitals in 11 provinces/municipalities representing all geographical divisions of China.Patient epidemiological and clinical features,treatment status,and total and daily costs were recorded.Trends in the percentage of traumatic spinal cord injuries among all hospitalized patients and among patients hospitalized in the orthopedic department and cost of care were assessed by annual percentage change using the Joinpoint Regression Program.The percentage of traumatic spinal cord injuries among all hospitalized patients and among patients hospitalized in the orthopedic department did not significantly change overall(annual percentage change,-0.5%and 2.1%,respectively).A total of 10,053(74.7%)patients underwent surgery.Only 2.8%of patients who underwent surgery did so within 24 hours of injury.A total of 2005(14.9%)patients were treated with high-dose(≥500 mg)methylprednisolone sodium succinate/methylprednisolone(MPSS/MP);615(4.6%)received it within 8 hours.The total cost for acute traumatic spinal cord injury decreased over the study period(-4.7%),while daily cost did not significantly change(1.0%increase).Our findings indicate that public health initiatives should aim at improving hospitals’ability to complete early surgery within 24 hours,which is associated with improved sensorimotor recovery,increasing the awareness rate of clinical guidelines related to high-dose MPSS/MP to reduce the use of the treatment with insufficient evidence.展开更多
The aim of this study is to investigate the impacts of the sampling strategy of landslide and non-landslide on the performance of landslide susceptibility assessment(LSA).The study area is the Feiyun catchment in Wenz...The aim of this study is to investigate the impacts of the sampling strategy of landslide and non-landslide on the performance of landslide susceptibility assessment(LSA).The study area is the Feiyun catchment in Wenzhou City,Southeast China.Two types of landslides samples,combined with seven non-landslide sampling strategies,resulted in a total of 14 scenarios.The corresponding landslide susceptibility map(LSM)for each scenario was generated using the random forest model.The receiver operating characteristic(ROC)curve and statistical indicators were calculated and used to assess the impact of the dataset sampling strategy.The results showed that higher accuracies were achieved when using the landslide core as positive samples,combined with non-landslide sampling from the very low zone or buffer zone.The results reveal the influence of landslide and non-landslide sampling strategies on the accuracy of LSA,which provides a reference for subsequent researchers aiming to obtain a more reasonable LSM.展开更多
This study examines the spatio-temporal characteristics of heavy precipitation forecasts in eastern China from the European Centre for Medium-Range Weather Forecasts(ECMWF) using the time-domain version of the Method ...This study examines the spatio-temporal characteristics of heavy precipitation forecasts in eastern China from the European Centre for Medium-Range Weather Forecasts(ECMWF) using the time-domain version of the Method for Object-based Diagnostic Evaluation(MODE-TD). A total of 23 heavy rainfall cases occurring between 2018 and 2021 are selected for analysis. Using Typhoon “Rumbia” as a case study, the paper illustrates how the MODE-TD method assesses the overall simulation capability of models for the life history of precipitation systems. The results of multiple tests with different parameter configurations reveal that the model underestimates the number of objects’ forecasted precipitation tracks, particularly at smaller radii. Additionally, the analysis based on centroid offset and area ratio tests for different classified precipitation objects indicates that the model performs better in predicting large-area, fast-moving, and longlifespan precipitation objects. Conversely, it tends to have less accurate predictions for small-area, slow-moving, and shortlifespan precipitation objects. In terms of temporal characteristics, the model overestimates the forecasted movement speed for precipitation objects with small-area, slow movement, or both long and short lifespans while underestimating it for precipitation with fast movement. In terms of temporal characteristics, the model tends to overestimate the forecasted movement speed for precipitation objects with small-area, slow movement, or both long and short lifespans while underestimating it for precipitation with fast movement. Overall, the model provides more accurate predictions for the duration and dissipation of precipitation objects with large-area or long-lifespan(such as typhoon precipitation) while having large prediction errors for precipitation objects with small-area or short-lifespan. Furthermore, the model’s simulation results regarding the generation of precipitation objects show that it performs relatively well in simulating the generation of large-area and fast-moving precipitation objects. However, there are significant differences in the forecasted generation of small-area and slow-moving precipitation objects after 9 hours.展开更多
Over the past few decades,the Internet has rapidly diffused across China.The spread of the Internet has had a profound economic and social impact on Chinese rural areas.Existing research shows that Internet access sig...Over the past few decades,the Internet has rapidly diffused across China.The spread of the Internet has had a profound economic and social impact on Chinese rural areas.Existing research shows that Internet access significantly impacts agricultural production and improves smallholder farmers’income.Beyond these,the Internet can affect other dimensions of social welfare.However,research about the impact of Internet access on dietary quality in rural China remains scarce.This study utilizes multi-period panel data from Fixed Observation Point in rural China from 2009 to 2015 to estimate the impact of Internet access on dietary quality and food consumption of rural households and conducts a causal analysis.Regression models with time and household fixed effects allow robust estimation while reducing potential issues of unobserved heterogeneity.The estimates show that Internet access has significantly increased rural household dietary quality(measured by the Chinese Diet Balance Index).Further research finds that Internet access has increased the consumption of animal products,such as aquatic and dairy products.We also examine the underlying mechanisms.Internet access improves dietary quality and food consumption mainly through increasing household income and food expenditure.These results encourage the promotion of Internet access as a valuable tool for nutritional improvements,especially in rural areas.展开更多
基金supported by the National Natural Science Foundation of China(Project No.41920104007 and 41772334).
文摘Red clay landslides are widely distributed worldwide,resulting in severe loss of life and property.Although rainfall-induced red clay slopes have received extensive attention,the role of cracks in the evolutionary process of red clay slopes and their connection to failure mechanisms is still poorly understood.A comprehensive approach integrating field investigation,laboratory tests,and numerical simulations was conducted to study the 168 red clay landslides in Xinshao County,China.The results show that red clay is prone to forming cracks at high moisture content due to its low swelling and high shrinkage properties.The failure mode of red clay slopes can be summarized in three stages:crack generation,slope excavation,and slope failure.Furthermore,the retrospective analysis and numerical simulations of the typical landslide in Guanchong indicated that intense rainfall primarily impacts the shallow layer of soil within approximately 0.5 m on the intact slope.However,cracks change the pattern of rainfall infiltration in the slope.Rainwater infiltrates rapidly through the preferential channels induced by the cracks rather than uniformly and slowly from the slope surface.This results in a significant increase in both the depth of infiltration and the saturated zone area of the cracked slope,reaching 3.8 m and 36.2 m^(2),respectively.Consequently,the factor of safety of the slope decreases by 13.4%compared to the intact slope,ultimately triggering landslides.This study can provide valuable insights into understanding the failure mechanisms of red clay slopes in China and other regions with similar geological settings.
基金Under the auspices of the Philosophy and Social Science Planning Project of Guizhou,China(No.21GZZD59)。
文摘China’s low-carbon development path will make significant contributions to achieving global sustainable development goals.Due to the diverse natural and economic conditions across different regions in China,there exists an imbalance in the distribution of car-bon emissions.Therefore,regional cooperation serves as an effective means to attain low-carbon development.This study examined the pattern of carbon emissions and proposed a potential joint emission reduction strategy by utilizing the industrial carbon emission intens-ity(ICEI)as a crucial factor.We utilized social network analysis and Local Indicators of Spatial Association(LISA)space-time trans-ition matrix to investigate the spatiotemporal connections and discrepancies of ICEI in the cities of the Pearl River Basin(PRB),China from 2010 to 2020.The primary drivers of the ICEI were determined through geographical detectors and multi-scale geographically weighted regression.The results were as follows:1)the overall ICEI in the Pearl River Basin is showing a downward trend,and there is a significant spatial imbalance.2)There are numerous network connections between cities regarding the ICEI,but the network structure is relatively fragile and unstable.3)Economically developed cities such as Guangzhou,Foshan,and Dongguan are in the center of the network while playing an intermediary role.4)Energy consumption,industrialization,per capita GDP,urbanization,science and techno-logy,and productivity are found to be the most influential variables in the spatial differentiation of ICEI,and their combination in-creased the explanatory power of the geographic variation of ICEI.Finally,through the analysis of differences and connections in urban carbon emissions under different economic levels and ICEI,the study suggests joint carbon reduction strategies,which are centered on carbon transfer,financial support,and technological assistance among cities.
基金supported by the National Science Foundation of China(42101082)the Science Foundation of Fujian Province(2023J01496).
文摘Long-term temperature variations inferred from high-resolution proxies provide an important context to evaluate the intensity of current warming.However,tem-perature reconstructions in humid southeastern China are scarce and particularly lack long-term data,limiting us to obtain a complete picture of regional temperature evolution.In this study,we present a well-verified reconstruction of winter-spring(January–April)minimum temperatures over southeastern China based on stable carbon isotopic(δ^(13)C)records of tree rings from Taxus wallichiana var.mairei from 1860 to 2014.This reconstruction accounted for 56.4%of the total observed variance.Cold periods occurred during the 1860s–1910s and 1960s–1970s.Although temperatures have had an upward trend since the 1920s,most of the cold extremes were in recent decades.The El Niño-Southern Oscillation(ENSO)variance acted as a key modulator of regional winter-spring minimum temperature variability.However,teleconnections between them were a nonlinear process,i.e.,a reduced or enhanced ENSO variance may result in a weakened or intensified temperature-ENSO relationship.
基金supported by the National Key R&D Program for Developing Basic Sciences(2022YFC3104802).
文摘Employing the nonlinear local Lyapunov exponent (NLLE) technique, this study assesses the quantitative predictability limit of oceanic mesoscale eddy (OME) tracks utilizing three eddy datasets for both annual and seasonal means. Our findings reveal a discernible predictability limit of approximately 39 days for cyclonic eddies (CEs) and 44 days for anticyclonic eddies (AEs) within the South China Sea (SCS). The predictability limit is related to the OME properties and seasons. The long-lived, large-amplitude, and large-radius OMEs tend to have a higher predictability limit. The predictability limit of AE (CE) tracks is highest in autumn (winter) with 52 (53) days and lowest in spring (summer) with 40 (30) days. The spatial distribution of the predictability limit of OME tracks also has seasonal variations, further finding that the area of higher predictability limits often overlaps with periodic OMEs. Additionally, the predictability limit of periodic OME tracks is about 49 days for both CEs and AEs, which is 5-10 days higher than the mean values. Usually, in the SCS, OMEs characterized by high predictability limit values exhibit more extended and smoother trajectories and often move along the northern slope of the SCS.
基金supported by the Third Xinjiang Scientific Expedition Program (2022xjkk1205)the Tianshan Talent Training Program (2023TSYCTD0084)+2 种基金the Science and Technology Major Program of Xinjiang Uygur Autonomous Region (2023A01002)the Young Top Talents of Xinjiang Normal University (XJNUQB2022-29)the Youth Innovation Promotion Association of the Chinese Academy of Sciences (2020437)
文摘In the context of changes in global climate and land uses,biodiversity patterns and plant species distributions have been significantly affected.Soil salinization is a growing problem,particularly in the arid areas of Northwest China.Halophytes are ideal for restoring soil salinization because of their adaptability to salt stress.In this study,we collected the current and future bioclimatic data released by the WorldClim database,along with soil data from the Harmonized World Soil Database(v1.2)and A Big Earth Data Platform for Three Poles.Using the maximum entropy(MaxEnt)model,the potential suitable habitats of six halophytic plant species(Halostachys caspica(Bieb.)C.A.Mey.,Halogeton glomeratus(Bieb.)C.A.Mey.,Kalidium foliatum(Pall.)Moq.,Halocnemum strobilaceum(Pall.)Bieb.,Salicornia europaea L.,and Suaeda salsa(L.)Pall.)were assessed under the current climate conditions(average for 1970-2000)and future(2050s,2070s,and 2090s)climate scenarios(SSP245 and SSP585,where SSP is the Shared Socio-economic Pathway).The results revealed that all six halophytic plant species exhibited the area under the receiver operating characteristic curve values higher than 0.80 based on the MaxEnt model,indicating the excellent performance of the MaxEnt model.The suitability of the six halophytic plant species significantly varied across regions in the arid areas of Northwest China.Under different future climate change scenarios,the suitable habitat areas for the six halophytic plant species are expected to increase or decrease to varying degrees.As global warming progresses,the suitable habitat areas of K.foliatum,S.salsa,and H.strobilaceum exhibited an increasing trend.In contrast,the suitable habitat areas of H.glomeratus,S.europaea,and H.caspica showed an opposite trend.Furthermore,considering the ongoing global warming trend,the centroids of the suitable habitat areas for various halophytic plant species would migrate to different degrees,and four halophytic plant species,namely,S.salsa,H.strobilaceum,H.glomeratus,and H.capsica,would migrate to higher latitudes.Temperature,precipitation,and soil factors affected the possible distribution ranges of these six halophytic plant species.Among them,precipitation seasonality(coefficient of variation),precipitation of the warmest quarter,mean temperature of the warmest quarter,and exchangeable Na+significantly affected the distribution of halophytic plant species.Our findings are critical to comprehending and predicting the impact of climate change on ecosystems.The findings of this study hold significant theoretical and practical implications for the management of soil salinization and for the utilization,protection,and management of halophytes in the arid areas of Northwest China.
基金Under the auspices of the National Natural Science Foundation of China(No.41971219,41571168)Natural Science Foundation of Hunan Province(No.2020JJ4372)Philosophy and Social Science Fund Project of Hunan Province(No.18ZDB015)。
文摘Terrestrial carbon storage(CS)plays a crucial role in achieving carbon balance and mitigating global climate change.This study employs the Shared Socioeconomic Pathways and Representative Concentration Pathways(SSPs-RCPs)published by the Intergovernmental Panel on Climate Change(IPCC)and incorporates the Policy Control Scenario(PCS)regulated by China’s land management policies.The Future Land Use Simulation(FLUS)model is employed to generate a 1 km resolution land use/cover change(LUCC)dataset for China in 2030 and 2060.Based on the carbon density dataset of China’s terrestrial ecosystems,the study analyses CS changes and their relationship with land use changes spanning from 1990 to 2060.The findings indicate that the quantitative changes in land use in China from 1990 to 2020 are characterised by a reduction in the area proportion of cropland and grassland,along with an increase in the impervious surface and forest area.This changing trend is projected to continue under the PCS from 2020 to 2060.Under the SSPs-RCPs scenario,the proportion of cropland and impervious surface predominantly increases,while the proportions of forest and grassland continuously decrease.Carbon loss in China’s carbon storage from 1990 to 2020 amounted to 0.53×10^(12)kg,primarily due to the reduced area of cropland and grassland.In the SSPs-RCPs scenario,more significant carbon loss occurs,reaching a peak of8.07×10^(12)kg in the SSP4-RCP3.4 scenario.Carbon loss is mainly concentrated in the southeastern coastal area and the Beijing-TianjinHebei(BTH)region of China,with urbanisation and deforestation identified as the primary drivers.In the future,it is advisable to enhance the protection of forests and grassland while stabilising cropland areas and improving the intensity of urban land.These research findings offer valuable data support for China’s land management policy,land space optimisation,and the achievement of dual-carbon targets.
基金Under the auspices of National Natural Science Foundation of China(No.42071230)。
文摘China has resolved its overall regional poverty in 2020 by attaining moderate societal prosperity.The country has entered a new development stage designed to achieve its second centenary goal.However,ecological fragility and risk susceptibility have increased the risk of returning to ecological poverty.In this paper,the Liupan Mountain Region of China was used as a case study,and the counties were used as the scale to reveal the spatiotempora differentiation and influcing factors of the risk of returning to poverty in study area.The indicator data for returning to ecological poverty from 2011-2020 were collected and summarized in three dimensions:ecological,economic and social.The autoregressive integrated moving average model(ARIMA)time series and exponential smoothing method(ES)were used to predict the multidimensional indicators of returning to ecological poverty for 61 counties(districts)in the Liupan Mountain Region for 2021-2030.The back propagation neural network(BPNN)and geographic information system(GIS)were used to generate the spatial distribution and time variation for the index of the risk of returning to ecological poverty(RREP index).The results show that 1)ecological factors were the main factors in the risk of returning to ecological poverty in Liupan Mountain Region.2)The RREP index for the 61 counties(districts)exhibited a downward trend from 2021-2030.The RREP index declined more in medium-and high-risk areas than in low-risk areas.From 2021 to 2025,the RREP index exhibited a slight downward trend.From 2026 to2030,the RREP index was expected to decline faster,especially from 2029-2030.3)Based on the RREP index,it can be roughly divided into three types,namely,the high-risk areas,the medium-risk areas,and the low-risk areas.The natural resource conditions in lowrisk areas of returning to ecological poverty,were better than those in medium-and high-risk areas.
基金The authors acknowledge the financial support from the Australian Centre for International Agricultural Research(ADP/2017/024)the National Natural Science Foundation of China(71934003)+1 种基金the National Social Science Fundof China(19ZDA002 and 22CJL003)the International Fund for Agricultural Development(2000000866).
文摘China has experienced rapid rural transformation in the past four decades.Accompanying the rapid transformation is a significant rise in rural household income and a substantial fall in rural poverty.This paper examines the evolutions of and the relationships between rural transformation(high-value agriculture and rural non-farm employment)and its outcomes(per capita rural income and rural poverty incidence)using provincial-level data.The results show that 31 provinces/autonomous regions/municipalities have undergone significant rural transformation,but the level and speed of rural transformation differed considerably.Moreover,an increased level of rural transformation is often associated with higher per capita rural income and reduced rural poverty incidence.Notably,a category of provincial rural transformation based on high-value agriculture and rural non-farm employment is also analyzed.We further discuss the likely impacts of institutions,policies,and investments(IPIs)on rural transformation and conclude with policy implications.
基金supported by the National Natural Science Foundation of China(Grant Nos.42088101 and 42175033)the High-Performance Computing Center of Nanjing University of Information Science&Technology。
文摘Extreme high temperatures frequently occur in southwestern China,significantly impacting the local ecological system and economic development.However,accurate prediction of extreme high-temperature days(EHDs)in this region is still an unresolved challenge.Based on the spatiotemporal characteristics of EHDs over China,a domain-averaged EHD index over southwestern China(SWC-EHDs)during April-May is defined.The simultaneous dynamic and thermodynamic fields associated with the increased SWC-EHDs are a local upper-level anticyclonic(high-pressure)anomaly and wavy geopotential height anomaly patterns over Eurasia.In tracing the origins of the lower boundary anomalies,two physically meaningful precursors are detected for SWC-EHDs.They are the tripolar SST change tendency from December-January to February-March in the northern Atlantic and the February-March mean snow depth in central Asia.Using these two selected predictors,a physics-based empirical model prediction was applied to the training period of 1961–2005 to obtain a skillful prediction of the EHDs index,attaining a correlation coefficient of 0.76 in the independent prediction period(2006–19),suggesting that 58%of the total SWC-EHDs variability is predictable.This study provides an estimate for the lower bound of the seasonal predictability of EHDs as well as for the hydrological drought over southwestern China.
基金supported by the National Natural Science Foundation of China (Grant No. 41831175)the Fundamental Research Funds for the Central Universities (Grant No. B210201029)+2 种基金the Key Scientific and Technological Project of the Ministry of Water Resources, P. R. China (SKS2022001)the Joint Open Project of the KLME and CIC-FEMD (Grant No. KLME202202)the Open Research Fund of the State Key Laboratory of Tropical Oceanography (South China Sea Institute of Oceanology, Chinese Academy of Sciences) (Grant No. LTO2110)
文摘Seasonal prediction of summer precipitation over eastern China is closely linked to the East Asian monsoon circulation,which is largely affected by the El Niño-Southern Oscillation(ENSO).In this study,results show that spring soil moisture(SM)over the Indo-China peninsula(ICP)could be a reliable seasonal predictor for eastern China summer precipitation under non-ENSO conditions.When springtime SM anomalies are present over the ICP,they trigger a structured response in summertime precipitation over most of eastern China.The resultant south-to-north,tri-polar configuration of precipitation anomalies has a tendency to yield increased(decreased)precipitation in the Yangtze River basin and decreased(increased)in South and North China with a drier(wetter)spring soil condition in the ICP.The analyses show that ENSO exerts a powerful control on the East Asian circulation system in the ENSO-decaying summer.In the case of ENSO forcing,the seasonal predictability of the ICP spring SM for eastern China summer precipitation is suppressed.However,in the absence of the influence of ENSO sea surface temperature anomalies from the preceding winter,the SM anomalies over the ICP induce abnormal local heating and a consequent geopotential height response owing to its sustained control on local temperature,which could,in turn,lead to abnormal eastern China summer precipitation by affecting the East Asian summer monsoon circulation.The present findings provide a better understanding of the complexity of summer climate predictability over eastern China,which is of potential significance for improving the livelihood of the people.
基金the National Natural Science Foundation of China(Nos.U20A2097,42175042)the Natural Science Foundation of Sichuan(Nos.2022NSFSC1056,2023NSFSC0246)+3 种基金the China Scholarship Council(No.201908510031)the Plateau and Basin Rainstorm,Drought and Flood Key Laboratory of Sichuan Province(Nos.SCQXKJZD202102-6,SCQXKJYJXMS202102)the Innovation Team Fund of Southwest Regional Meteorological Center,China Meteorological Administration(No.XNQYCXTD202201)the Sichuan Science and Technology Program(No.2022YFS0544).
文摘The prediction of precipitation at subseasonal to seasonal(S2S)timescales remains an enormous challenge because of the gap between weather and climate predictions.This study compares three deep learning algorithms,namely,the long short-term memory recurrent(LSTM),gated recurrent unit(GRU),and recurrent neural network(RNN),and selects the optimal algorithm to establish an S2S precipitation prediction model.The models were evaluated in four subregions of the Sichuan Province:the Plateau,Valley,eastern Basin,and western Basin.The results showed that the RNN model had better performance than the LSTM and GRU models.This could be because the RNN model had an advantage over the LSTM model in the transformation of climate indices with positive and negative variations.In the validation of test datasets,the RNN model successfully predicted the precipitation trend in most years during the wet season(May-October).The RNN model had a lower prediction bias(within±10%),higher sign accuracy of the precipitation trend(~88.95%),and greater accuracy of the maximum precipitation month(>0.85).For the prediction of different lead times,the RNN model was able to provide a stable trend prediction for summer precipitation,and the time correlation coefficient score was higher than that of the National Climate Center of China.Furthermore,this study proposed a method to measure the sensitivity of the RNN model to different input features,which may provide unprecedented insights into the nonlinear relationship and complicated feedback process among climate systems.The results of the sensitivity distribution are as follows.First,the Niño 4 and Niño 3.4 indices were equally important for the prediction of wet season precipitation.Second,the sensitivity of the snow cover on the Tibetan Plateau was higher than that in the Northern Hemisphere.Third,an opposite sensitivity appeared in two different patterns of the Indian Ocean and sea ice concentrations in the Arctic and the Barents Sea.
基金supported by the Russian Science Foundation grant(No.22-15-00120)supported by the grant(No.21-2-10-59-1)from the Foundation for the Development of Theoretical Physics and Mathematics BASIS.
文摘Red blood cell(RBC)aggregation as well as their deformation signi¯cantly affects blood microrheology.These processes depend on various factors,one of which is concentration of the nitric oxide,one of the main signaling molecule in the bloodstream.The purpose of this study was to investigate the effect of nitric oxide on the microrheological properties of red blood cells(RBCs)in RBC samples of various media after the addition of nitric oxide donor sodium nitroprusside in vitro.Microrheological properties were measured using laser aggregometer and ektacytometer based on diffuse light scattering and diffraction of laser light on a suspension of RBCs,respectively.The study found that heparin-stabilized blood showed increased RBC aggregation and deformation with sodium nitroprusside concentrations of 100,and 200M,while EDTA-stabilized blood showed slightly decreased aggregation and unchanged deformation.With washed RBCs in dextran solution,the addition of sodium nitroprusside(in the concentrations of 100,and 200M)resulted in decreased aggregation and increased deformation.These-ndings aid in our understanding of nitric oxide's effect on RBC microrheological properties.
基金supported by the Regional Collaborative Innovation Project in Xinjiang Autonomous Region of China(2022E02011)the National Key R&D Program of China(2019YFD1002500)the Key Project of Research and Development Plan in Ningxia Hui Autonomous Region of China(2018BBF02001)。
文摘The impact of cyclodextrins(CDs)on wine quality and stability remains largely unknown.This study systematically assessed the protective effect of the post-fermentation addition of CDs on color stability of red wine from the viewpoints of color characteristics,copigmentation and phenolic profiles.The grey relational analysis(GRA)and principal component analysis(PCA)methods were employed to dissect the key effective determinants related to color quality.The addition of CDs induced a significant hyperchromic effect of 8.19-25.40%,a significant bathochromic effect and an enhancement of the color intensity.Furthermore,the evolution of anthocyanin forms and the content of monomeric anthocyanins revealed that β-CD is a superior favorable cofactor during wine aging,but for long-term aging,2-HP-β-CD and 2-HP-γ-CD are more beneficial in promoting the formation of polymerized anthocyanins and color stability.This work provides an important reference for the use of CDs to enhance the color quality and stability of red wines.
基金This paper was supported by the National Natural Science Foundation of China(NSFC)(71973138 and 72061137002)the Ministry of Science and Technology of China(2023YFE0105009).
文摘A more resilient livelihood is increasingly recognized as an efficient way to improve vulnerable households’food security and optimize their dietary decisions.This study quantifies rural household resilience in western China,identifies the three pillars(absorptive capacity,adaptive capacity,and transformative capacity)contribution to resilience,and then establishes the estimated Resilience Capacity Index(RCI)linked with food security and dietary diversity supported by the multiple indicator multiple cause(MIMIC)model.Results show that,despite geographical heterogeneity,the RCI consistently increased from 2015 to 2021.Households with a higher RCI inheriting better capacity to deal with risk and shocks are significantly and positively correlated with increasing food expenditure and diversifying food choices.It can be because resilient households will allocate more money to food expenditure instead of saving for livelihood uncertainty.Thus,policymakers can provide more incentives for rural households to adopt more dynamic and effective risk management strategies.This,in turn,could yield positive spillover effects by preventing human capital loss associated with dietary-related chronic diseases and mortality.
基金supported by the National Key Research and Development Project,No.2019YFA0112100(to SF).
文摘Traumatic spinal cord injury is potentially catastrophic and can lead to permanent disability or even death.China has the largest population of patients with traumatic spinal cord injury.Previous studies of traumatic spinal cord injury in China have mostly been regional in scope;national-level studies have been rare.To the best of our knowledge,no national-level study of treatment status and economic burden has been performed.This retrospective study aimed to examine the epidemiological and clinical features,treatment status,and economic burden of traumatic spinal cord injury in China at the national level.We included 13,465 traumatic spinal cord injury patients who were injured between January 2013 and December 2018 and treated in 30 hospitals in 11 provinces/municipalities representing all geographical divisions of China.Patient epidemiological and clinical features,treatment status,and total and daily costs were recorded.Trends in the percentage of traumatic spinal cord injuries among all hospitalized patients and among patients hospitalized in the orthopedic department and cost of care were assessed by annual percentage change using the Joinpoint Regression Program.The percentage of traumatic spinal cord injuries among all hospitalized patients and among patients hospitalized in the orthopedic department did not significantly change overall(annual percentage change,-0.5%and 2.1%,respectively).A total of 10,053(74.7%)patients underwent surgery.Only 2.8%of patients who underwent surgery did so within 24 hours of injury.A total of 2005(14.9%)patients were treated with high-dose(≥500 mg)methylprednisolone sodium succinate/methylprednisolone(MPSS/MP);615(4.6%)received it within 8 hours.The total cost for acute traumatic spinal cord injury decreased over the study period(-4.7%),while daily cost did not significantly change(1.0%increase).Our findings indicate that public health initiatives should aim at improving hospitals’ability to complete early surgery within 24 hours,which is associated with improved sensorimotor recovery,increasing the awareness rate of clinical guidelines related to high-dose MPSS/MP to reduce the use of the treatment with insufficient evidence.
文摘The aim of this study is to investigate the impacts of the sampling strategy of landslide and non-landslide on the performance of landslide susceptibility assessment(LSA).The study area is the Feiyun catchment in Wenzhou City,Southeast China.Two types of landslides samples,combined with seven non-landslide sampling strategies,resulted in a total of 14 scenarios.The corresponding landslide susceptibility map(LSM)for each scenario was generated using the random forest model.The receiver operating characteristic(ROC)curve and statistical indicators were calculated and used to assess the impact of the dataset sampling strategy.The results showed that higher accuracies were achieved when using the landslide core as positive samples,combined with non-landslide sampling from the very low zone or buffer zone.The results reveal the influence of landslide and non-landslide sampling strategies on the accuracy of LSA,which provides a reference for subsequent researchers aiming to obtain a more reasonable LSM.
基金National Key Research and Development Program of China (2021YFC3000802)National Natural Science Foundation of China (41875059)The Open Research Program of the State Key Laboratory of Severe Weather (2021LASW-A04)。
文摘This study examines the spatio-temporal characteristics of heavy precipitation forecasts in eastern China from the European Centre for Medium-Range Weather Forecasts(ECMWF) using the time-domain version of the Method for Object-based Diagnostic Evaluation(MODE-TD). A total of 23 heavy rainfall cases occurring between 2018 and 2021 are selected for analysis. Using Typhoon “Rumbia” as a case study, the paper illustrates how the MODE-TD method assesses the overall simulation capability of models for the life history of precipitation systems. The results of multiple tests with different parameter configurations reveal that the model underestimates the number of objects’ forecasted precipitation tracks, particularly at smaller radii. Additionally, the analysis based on centroid offset and area ratio tests for different classified precipitation objects indicates that the model performs better in predicting large-area, fast-moving, and longlifespan precipitation objects. Conversely, it tends to have less accurate predictions for small-area, slow-moving, and shortlifespan precipitation objects. In terms of temporal characteristics, the model overestimates the forecasted movement speed for precipitation objects with small-area, slow movement, or both long and short lifespans while underestimating it for precipitation with fast movement. In terms of temporal characteristics, the model tends to overestimate the forecasted movement speed for precipitation objects with small-area, slow movement, or both long and short lifespans while underestimating it for precipitation with fast movement. Overall, the model provides more accurate predictions for the duration and dissipation of precipitation objects with large-area or long-lifespan(such as typhoon precipitation) while having large prediction errors for precipitation objects with small-area or short-lifespan. Furthermore, the model’s simulation results regarding the generation of precipitation objects show that it performs relatively well in simulating the generation of large-area and fast-moving precipitation objects. However, there are significant differences in the forecasted generation of small-area and slow-moving precipitation objects after 9 hours.
基金This study was supported in part by the National Natural Science Foundation of China(71973136 and 72061147002)the 2115 Talent Development Program of China Agricultural University.
文摘Over the past few decades,the Internet has rapidly diffused across China.The spread of the Internet has had a profound economic and social impact on Chinese rural areas.Existing research shows that Internet access significantly impacts agricultural production and improves smallholder farmers’income.Beyond these,the Internet can affect other dimensions of social welfare.However,research about the impact of Internet access on dietary quality in rural China remains scarce.This study utilizes multi-period panel data from Fixed Observation Point in rural China from 2009 to 2015 to estimate the impact of Internet access on dietary quality and food consumption of rural households and conducts a causal analysis.Regression models with time and household fixed effects allow robust estimation while reducing potential issues of unobserved heterogeneity.The estimates show that Internet access has significantly increased rural household dietary quality(measured by the Chinese Diet Balance Index).Further research finds that Internet access has increased the consumption of animal products,such as aquatic and dairy products.We also examine the underlying mechanisms.Internet access improves dietary quality and food consumption mainly through increasing household income and food expenditure.These results encourage the promotion of Internet access as a valuable tool for nutritional improvements,especially in rural areas.