In order to improve the added value of the main vegetable products in Qinghai Province,we researched the effect of soil selenium content on vegetable quality in selenium-enriched area of Qinghai. Through the analysis ...In order to improve the added value of the main vegetable products in Qinghai Province,we researched the effect of soil selenium content on vegetable quality in selenium-enriched area of Qinghai. Through the analysis of Qinghai selenium-enriched soil selenium content and5 kinds of main vegetables corresponds to the total selenium,part of the mineral elements and soluble sugar and VC content,the effects of soil selenium levels on selenium absorption and nourishment quality of vegetables were researched. The results showed that he Qinghai selenium-enriched soil selenium content in the range of 100. 00-563. 00 μg/kg,among them,the soil samples with sufficient selenium and rich selenium accounted for 76. 53% and 18. 88%,respectively. Soil selenium content of garlic sampling area was relatively high,and soil selenium content of sugar beet sampling area was relatively low. Vegetable selenium content was in the range of 11. 00-340. 94 μg/kg,the average content of total selenium content of garlic was up to 170. 40 μg/kg,and the average content of the total selenium content of radish is 73. 00 μg/kg.90. 63% of the vegetables in the region reached the level of sufficient selenium,and 70. 31% reached the level of selenium enrichment. The average content of Ca and Mg was higher than the national average. There was no significant correlation between selenium content of soil and vegetable and nutritional quality.展开更多
The promotion of rural revitalization within the ecological conservation areas(“ECAs”) requires a careful balance between ecological protection and economic development and should be guided by the principle of ecolo...The promotion of rural revitalization within the ecological conservation areas(“ECAs”) requires a careful balance between ecological protection and economic development and should be guided by the principle of ecological priority. The cultivation of rural “Local Specialty Products”(“LSPs”) under a green-development framework aligns with the functional positioning of these areas, drives the revitalization of rural industries, and constitutes a fundamental strategy for addressing the unique challenges they face. Although ECAs possess inherent advantages in terms of developing LSPs, they are also confronted by multiple constraints. Accordingly, we propose development objectives that emphasize(a) driving rural industrial prosperity,(b) enhancing the appeal of agricultural heritage, and(c) ensuring inclusive prosperity in the farming communities. In selecting pathways for growth, priority should be given to improving the quality of products, fostering distinctiveness of the technologies, nurturing cultural identities, and upholding the principle of common prosperity. From a policy standpoint, the development of rural LSPs should be recognized as a key lever for advancing the comprehensiveness of rural revitalization in the ECAs. We recommend a set of supportive measures—namely, reinforcing the guidance for spatial planning, integrating the consolidation of factor inputs, and ensuring the robustness of organizational guarantees—to facilitate the high-quality development of LSPs in these areas.展开更多
Background:The mobility of people in rural areas may lead to more and more left-behind children(LBC)appearing,and being an LBC brings a lot of risks to mental health,which could greatly hinder children’s development ...Background:The mobility of people in rural areas may lead to more and more left-behind children(LBC)appearing,and being an LBC brings a lot of risks to mental health,which could greatly hinder children’s development and undermine their happiness and safety in life.Previous scholars have conducted plenty of studies that focused on Chinese rural LBCs’mental health issues,such as what they exactly look like and some potential factors,but there remains a paucity of reviews about the relationship among certain mental health issues.We will try to figure out how the most common mental health issues of LBC in China’s rural areas correlate with each other,as well as their related factors.Methods:In this study,we used a systematic review approach to analyze 35 publications from Web of Science and EBSCO(to August 2025),followed by the sorting standards of Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)2020.Results:By mainly using quantitative techniques,we found that Chinese rural LBC are more likely to have mental health issues than children who have no experience of being left behind,and they often suffer from depression,social anxiety,internet addiction,and suicidal ideation.These four mental health issues share influencing factors and positively correlate with each other.We also found that Chinese rural LBCs are somewhat resilient towards the risk factors of mental health issues,and national or social policies and interventions can really help them a lot.Conclusion:For Chinese rural LBC,there are important relationships among the common psychological disorders they often suffer,along with multiple factors that affect their mental health,which can help related scholars and practitioners pay attention to such mechanisms and think more comprehensively when they try to help the children who are left behind.展开更多
It is essential to understand how adaptation needs and options differ among stakeholders in protected areas(PAs)to effectively implement climate change(CC)adaptation strategies.Using the Qiangtang PA in Xizang as a ca...It is essential to understand how adaptation needs and options differ among stakeholders in protected areas(PAs)to effectively implement climate change(CC)adaptation strategies.Using the Qiangtang PA in Xizang as a case study,this research examines CC adaptation needs and options from the perspectives of stakeholders across multiple administrative levels,including provincial,prefectural,county authorities,73 protection stations,and 13364 pastoralists residing within the PA.The findings show that stakeholders at the provincial level,as well as those from the Ali and Naqu prefectures and six counties,place greater emphasis on institutional and resource-related needs than on other categories(attention score:7.0-9.3 vs.5.0-7.0).In contrast,stakeholders from the 73 protection stations prioritize technological and capacity-building needs more strongly than other types(attention score:8.0-9.0 vs.4.0-8.0).The 13364 pastoralists assign the highest importance to social needs relative to other categories(attention score:9.0-9.5 vs.3.0-8.0).Most of the eight existing protection measures were found to indirectly support broader climate adaptation efforts.In particular,protective actions addressing fire,pests,and weather-related disasters can be classified as autonomous adaptation,while other measures generate outcomes that enhance adaptation capacity under specific conditions.Adaptation options,grouped into three main types and 13 subcategories,differ across stakeholder groups,although substantial overlap exists between these options and current protective actions,including ecosystem based adaptation strategies,adaptation-related practices,autonomous adaptation measures,and emergency interventions.Overall,these findings highlight the critical role of all stakeholders-especially staff from the 73 protection stations and the 13364 pastoralists-in the effective implementation of adaptation actions within the PA.展开更多
Differentiation in housing costs reinforces the concentration of low-income groups in lowrent residential areas through residential location sorting,making the surrounding employment opportunity environment a crucial ...Differentiation in housing costs reinforces the concentration of low-income groups in lowrent residential areas through residential location sorting,making the surrounding employment opportunity environment a crucial perspective for assessing urban inclusiveness.Using residential areas as the unit of analysis,this study proposed a multidimensional framework for evaluating the spatial equity of urban employment by jointly capturing disparities between opportunity supply and access across three dimensions: employment opportunity quantity,wage levels,and commuting accessibility.In addition,we compared spatial differentiation among residential area types under rentbased stratification.This study focused on Urumqi,a major city in Northwest China,and integrated multisource geospatial data for 3465 residential areas,including points of interest(POIs),online job postings,and rental data for residential areas.Empirical analyses were conducted using the Gini coefficient,location quotient,and Geographically Weighted Regression(GWR) model.The findings reveal marked disparities in employment access across ring road areas and rent-based groups.In the urban core,low-rent residential areas benefit from relatively favorable commuting conditions;however,the accessible employment opportunities are concentrated in low-wage service sectors.In the peripheral zone,low-rent residential areas face a dual disadvantage of limited nearby employment supply and longer commuting distances.Even when spatial conditions are comparable,low-rent residential areas are systematically disadvantaged relative to non-low-rent residential areas in realized access to both employment opportunity quantity and wage levels.This pattern indicated that capability constraints impede the conversion of spatial resources into effective access.Further analyses highlight housing costs,infrastructure quality,and residential location as key associated factors.The findings underscored the importance of coordinated,targeted policies in affordable housing delivery,the spatial distribution of employment opportunities,and improvements in transport accessibility to promote urban spatial justice.展开更多
Addressing the widespread issues of internal fragmentation within protected areas and the neglect of surrounding critical habitat networks,this study aims to develop an assessment framework for the precise identificat...Addressing the widespread issues of internal fragmentation within protected areas and the neglect of surrounding critical habitat networks,this study aims to develop an assessment framework for the precise identification and remediation of regional conservation gaps.To this end,we introduce the Framework for Conservation Priority Identification(FCPI).The framework integrates Morphological Spatial Pattern Analysis(MSPA),the Remote Sensing Ecological Index(RSEI),Circuit Theory,and the Minimum Cumulative Resistance(MCR)model to formulate a multidimensional conservation priority index.This index facilitates the identification of critical ecological network components and enables the dynamic prioritization of conservation efforts.A case study of Fuzhou City from 2014 to 2020 reveals that despite an overall improvement in regional environmental quality,the functionality of core ecological sources has markedly declined.Between 2014 and 2020,the number of ecological sources grew by 76.9%,yet their total area shrank by 13.9%.Concurrently,the number of ecological corridors rose from 27 to 53,extending their total length by 380.23 km,which indicates an intensifying trend of habitat fragmentation.Furthermore,a significant number of crucial ecological network nodes,particularly within Minhou County,lie explicitly outside the existing protected area system.This confirms the presence of conservation gaps and unveils the spatiotemporal dynamics of shifting conservation priorities.The research validates that the proposed FCPI can effectively diagnose the dynamic deficiencies within conservation systems.It offers scientific decisionsupport for local governments,facilitating a transition from isolated conservation efforts towards systematic and comprehensive ecological network governance.展开更多
The establishment of plantations has become a critical approach for reducing greenhouse gas emissions,particularly in fragile environments with carbon sequestration potential.In karst areas,plantations based on fastgr...The establishment of plantations has become a critical approach for reducing greenhouse gas emissions,particularly in fragile environments with carbon sequestration potential.In karst areas,plantations based on fastgrowing afforestation species made significant contributions to enhancing carbon sequestration.However,the impact of understory vegetation on carbon accumulation remains unclear.Especially,the carbon accumulation associated with litter produced during the replacement of understory species receives insufficient attention,which leads to the neglect of the carbon sequestration potential in plantations of karst areas.Leaf is a crucial organ that links the litter production.To explore how leaf traits adapt to competitive environments and drive litter carbon accumulation during understory species replacement,this study observed leaf traits and litter carbon content changes in three types of plantations in the Liujiang River Basin,a typical karst area.A total of 37 sampling plots were selected for field investigation over a twoyear period.Leaf traits,species diversity,vegetation coverage,and litter carbon characteristics in understory vegetation were measured.Variance analysis,allometric equations,and path analysis were used for data analysis.The results showed that most understory species adopted a biomass conservation strategy under high-coverage conditions(>44.27%)and expanded competitive leaf area under low-coverage conditions(<44.27%).However,Bidens pilosa and Miscanthus floridulus exhibited strong competitiveness during understory species replacement.They showed an expansion of competitive leaf area under high-coverage conditions.This competitive strategy reduced species diversity and community specific leaf area.But the rapid expansion of Bidens pilosa and Miscanthus floridulus increased understory vegetation coverage,and their increased specific leaf area facilitated leaf shedding,resulting in significant litter weight accumulation(P<0.05),thereby enhancing litter carbon content per unit area.These competitive strategies were key driving factors for the increase in litter carbon content per square meter,which reached a maximum of 49.6% higher than that in natural grasslands.And the maximum increase in litter carbon accumulation derived from understory vegetation reached 3.37 times from 2023 to 2024 in plantations.In the understory vegetation of plantations,the competitive strategies reflected by leaf adaptation of key competitive species are critical factors influencing litter carbon accumulation.Future research could deeply explore the carbon sequestration effects resulting from the dynamic changes in competition within the understory vegetation of plantations.展开更多
The study aimed at predicting potential suitable areas with national key reserve Orchidaceae plants in Heilongjiang province and conducive to plant protection.The distribution point data of six Orchidaceae plants and ...The study aimed at predicting potential suitable areas with national key reserve Orchidaceae plants in Heilongjiang province and conducive to plant protection.The distribution point data of six Orchidaceae plants and 19 bioclimatic variables were selected,and the environmental factors required for modeling were screened out by pearson correlation analysis and variance inflation factor(VIF)analysis.The potential suitable areas of Orchidaceae plants were predictat present and under different climate scenarios in 2090s by using geographic information system(GIS)and Maximum Entropy Model(MaxEnt).And then evaluated the prediction accuracy of the MaxEnt model using the AUC value,the TSS value and the Kappa value.The results showed that:1)The area under curve(AUC)values,true skill statistics(TSS)values and KAPPA values predicted by MaxEnt model were separately above 0.9,0.85 and 0.75.2)Under the climate scenario at present,the total suitable area of Orchidaceae plants was about 9.61×10^(6)km^(2),which was mainly distributed in Heilongjiang province.Among them,the high-suitable area of Cypripedium shanxiense S.C.Chen was the largest,the non-suitable area of Cypripedium guttatum Sw was the largest.3)Under different climate scenarios in 2090s,the total suitable area was slightly increasing(9.62×10^(6)km^(2)).Among them,Cypripedium shanxiense S.C.Chen and Gastrodiae Rhizoma both showed the trend of expansion to the southwest,China,and the suitable areas expanded significantly.Comprehensive factor analysis showed that temperature and precipitation were the main bioclimatic variables of suitable areas distribution,and the low emission scenario(SSP 2-4.5)will be more conducive to the survival of Orchidaceae plants.展开更多
This paper presents an optimal operation method for embedded DC interconnections based on low-voltage AC/DC distribution areas(EDC-LVDA)under three-phase unbalanced compensation conditions.It can optimally determine t...This paper presents an optimal operation method for embedded DC interconnections based on low-voltage AC/DC distribution areas(EDC-LVDA)under three-phase unbalanced compensation conditions.It can optimally determine the transmission power of the DC and AC paths to simultaneously improve voltage quality and reduce losses.First,considering the embedded interconnected,unbalanced power structure of the distribution area,a power flow calculation method for EDC-LVDA that accounts for three-phase unbalanced compensation is introduced.This method accurately describes the power flow distribution characteristics under both AC and DC power allocation scenarios.Second,an optimization scheduling model for EDC-LVDA under three-phase unbalanced conditions is developed,incorporating network losses,voltage quality,DC link losses,and unbalance levels.The proposed model employs an improved particle swarm optimization(IPSO)two-layer algorithm to autonomously select different power allocation coefficients for the DC link and AC section under various operating conditions.This enables embedded economic optimization scheduling while maintaining compensation for unbalanced conditions.Finally,a case study based on the IEEE 13-node system for EDC-LVDA is conducted and tested.The results show that the proposed optimal operation method achieves a 100%voltage compliance rate and reduces network losses by 13.8%,while ensuring three-phase power balance compensation.This provides a practical solution for the modernization and upgrading of low-voltage power grids.展开更多
Impact craters are important for understanding the evolution of lunar geologic and surface erosion rates,among other functions.However,the morphological characteristics of these micro impact craters are not obvious an...Impact craters are important for understanding the evolution of lunar geologic and surface erosion rates,among other functions.However,the morphological characteristics of these micro impact craters are not obvious and they are numerous,resulting in low detection accuracy by deep learning models.Therefore,we proposed a new multi-scale fusion crater detection algorithm(MSF-CDA)based on the YOLO11 to improve the accuracy of lunar impact crater detection,especially for small craters with a diameter of<1 km.Using the images taken by the LROC(Lunar Reconnaissance Orbiter Camera)at the Chang’e-4(CE-4)landing area,we constructed three separate datasets for craters with diameters of 0-70 m,70-140 m,and>140 m.We then trained three submodels separately with these three datasets.Additionally,we designed a slicing-amplifying-slicing strategy to enhance the ability to extract features from small craters.To handle redundant predictions,we proposed a new Non-Maximum Suppression with Area Filtering method to fuse the results in overlapping targets within the multi-scale submodels.Finally,our new MSF-CDA method achieved high detection performance,with the Precision,Recall,and F1 score having values of 0.991,0.987,and 0.989,respectively,perfectly addressing the problems induced by the lesser features and sample imbalance of small craters.Our MSF-CDA can provide strong data support for more in-depth study of the geological evolution of the lunar surface and finer geological age estimations.This strategy can also be used to detect other small objects with lesser features and sample imbalance problems.We detected approximately 500,000 impact craters in an area of approximately 214 km2 around the CE-4 landing area.By statistically analyzing the new data,we updated the distribution function of the number and diameter of impact craters.Finally,we identified the most suitable lighting conditions for detecting impact crater targets by analyzing the effect of different lighting conditions on the detection accuracy.展开更多
We investigated the impact of convexity and isoperimetric deficits on the accuracy of sectional area estimates of tree stems using traditional methods(caliper,tape,formulas based on stem diameter and circumference).In...We investigated the impact of convexity and isoperimetric deficits on the accuracy of sectional area estimates of tree stems using traditional methods(caliper,tape,formulas based on stem diameter and circumference).In two complementary experiments,the use of photographs to estimate cross-sectional areas was first validated,then the use of a caliper and diameter tape was computer-simulated.The results indicated that the photographic method offers high precision,with mean relative errors below 0.1%,minimal deviation,and no significant bias,and the traditional methods led to substantial and systematic errors,with deviations from circularity and convexity significantly increasing the errors in area estimation.展开更多
Background Organic selenium(Se)has gained recognition in poultry nutrition as a feed additive to boost production and Se deposition in eggs and tissues,owing to its high bioavailability,efficient tissue accumulation a...Background Organic selenium(Se)has gained recognition in poultry nutrition as a feed additive to boost production and Se deposition in eggs and tissues,owing to its high bioavailability,efficient tissue accumulation and minimal toxicity.Selenium-enriched yeast(SeY)is a well-established source,while selenium-enriched lactobacilli(SeL),a newer alternative,offers the added benefits of probiotics.This study examined the effects of SeY and SeL on egg quality,antioxidant capacity,Se deposition,and gut health in laying hens.After a two-week pre-treatment with a Sedeficient diet(SeD),450 Hy-Line Brown laying hens(30-week-old)were assigned into five dietary groups with six replicates of 15 hens each.The groups included a SeD,SeD supplemented with 1.5 mg Se/kg from SeY(SeY15),or 1.5,3.0,and 6.0 mg Se/kg from SeL(SeL15,SeL30,SeL60).The feeding trial lasted for 12 weeks.Results SeY15 and SeL15 improved the feed-to-egg ratio(P<0.05)in the latter stages.Haugh units were significantly increased(P<0.05)in the SeY15 and SeL30 groups,while darker yolk color(P<0.05)was observed in the SeY15,SeL15,and SeL60 groups.All Se-supplemented diets increased Se content in whole eggs,albumen,and yolk(P<0.05),while SeL groups showed a dose-dependent effect.Antioxidant enzyme activities increased,and MDA content decreased in the serum(P<0.05),with SeY15 showing the highest GSH-Px levels(P<0.05).SeL60 increased serum alkaline phosphatase and aspartate transaminase,and distorted the liver architecture(P<0.05).Se-diets reduced concentrations of reactive oxygen species(ROS)in the ileum and liver(P<0.05).SeL15 improved the ileal villus height-tocrypt depth ratio(P<0.05).SeY15 and/or SeL15 up-regulated TXNRD1 and SEPHS1 mRNA while down-regulating SCLY expression in the liver.SeY15 altered ileal microbiota by increasing both beneficial and pathogenic bacteria,whereas SeL15 predominantly boosted beneficial bacteria.Conclusion SeL integrates the antioxidant properties of organic Se with the probiotic benefits on gut health,resulting in a performance-enhancing effect comparable to that of SeY.However,high SeL level(6.0 mg Se/kg)compromised productivity and metabolic functions while enhancing Se deposition.展开更多
The rapid population and land urbanization not only promoted economic development but also affected the ecosystem service value(ESV).In the context of new-type urbanization and green development,it’s essential to inv...The rapid population and land urbanization not only promoted economic development but also affected the ecosystem service value(ESV).In the context of new-type urbanization and green development,it’s essential to investigate the impacts of urbanization on ESV in China.However,a comprehensive and dynamic framework to reveal the relationship between ESV and urbanization processes is lacking.This study adopted multi-source datasets to portray China’s urbanization process by integrating population,land,and economic urbanization,eval-uated the ESV changes of 10 categories by gross ecosystem product(GEP)methods,and explored ESV changes within different urbanization scales and speeds.The results showed rapid urbanization in the population,land,and economic dimensions in China,with a faster process of economic urbanization.The ESV also exhibited an increasing trend,with higher levels in the southeastern coastal regions and lower levels in the northwestern regions.Urbanization had positive impacts on ESV across various research units,but the ESV exhibited heteroge-neous changes across different urbanization scales,speeds,and their interactive effects.The response of ESV to dynamic urbanization processes was influenced by socio-economic,ecological,and policy factors;it is essential to combine targeted measures with general ecological product value realization methods in each unit to maximize social-economic-ecological benefits.展开更多
Soil moisture(SM)is a critical variable in terrestrial ecosystems,especially in arid and semi-arid areas where water sources are limited.Despite its importance,understanding the spatiotemporal variations and influenci...Soil moisture(SM)is a critical variable in terrestrial ecosystems,especially in arid and semi-arid areas where water sources are limited.Despite its importance,understanding the spatiotemporal variations and influencing factors of SM in these areas remains insufficient.This study investigated the spatiotemporal variations and influencing factors of SM in arid and semi-arid areas of China by utilizing the extended triple collation(ETC),Mann-Kendall test,Theil-Sen estimator,ridge regression analysis,and other relevant methods.The following findings were obtained:(1)at the pixel scale,the long-term monthly SM data from the European Space Agency Climate Change Initiative(ESA CCI)exhibited the highest correlation coefficient of 0.794 and the lowest root mean square error(RMSE)of 0.014 m^(3)/m^(3);(2)from 2000 to 2022,the study area experienced significant increase in annual average SM,with a rate of 0.408×10^(-3)m^(3)/(m^(3)•a).Moreover,higher altitudes showed a notable upward trend,with SM increasing rates at 0.210×10^(-3)m^(3)/(m^(3)•a)between 1000 and 2000 m,0.530×10^(-3)m^(3)/(m^(3)•a)between 2000 and 4000 m,and 0.760×10^(-3)m^(3)/(m^(3)•a)at altitudes above 4000 m;(3)land surface temperature(LST),root zone soil moisture(RSM)(10-40 cm depth),and normalized difference vegetation index(NDVI)were identified as the primary factors influencing annual average SM,which accounted for 34.37%,24.16%,and 22.64%relative contributions,respectively;and(4)absolute contribution of LST was more significant in subareas at higher altitudes,with average absolute contributions of 0.800×10^(-3)m^(3)/(m^(3)•a)between 2000 and 4000 m and 0.500×10^(-2) m^(3)/(m^(3)•a)above 4000 m.This study reveals the spatiotemporal variations and main influencing factors of SM in Chinese arid and semi-arid areas,highlighting the more pronounced absolute contribution of LST to SM in high-altitude areas,providing valuable insights for ecological research and water resource management in these areas.展开更多
Based on comprehensive observations of 20 wire icing events during winter from 2019 to 2021,we investigated the characteristics of the icing properties,the atmospheric boundary layer structure,the raindrop size distri...Based on comprehensive observations of 20 wire icing events during winter from 2019 to 2021,we investigated the characteristics of the icing properties,the atmospheric boundary layer structure,the raindrop size distribution,and their associated effects on the ice accretion mechanism in the mountainous region of Southwest China.The maximum ice weight was positively correlated with the duration of ice accretion in the mountainous area.The duration of precipitation accounted for less than 20%of the icing period in the mountainous area,with solid-phase hydrometeors being predominant.Icing events,dominated by freezing rain(FR)and mixed rain–graupel(more than 70%),were characterized by glaze or highdensity mixed icing.The relationship between the melting energy and refreezing energy reflected the distribution characteristics of the proportion of FR under mixed-phase precipitation.The intensity of the warm layer and the dominant precipitation phase significantly affected the variations in the microphysical properties of FR.The melting of large dry snowflakes significantly contributed to FR in the mountainous areas,resulting in smaller generalized intercepts and larger mass-weighted mean diameters in the presence of a stronger warm layer.Under a weaker warm layer,the value of the massweighted mean diameter was significantly smaller because of the inability of large solid particles to melt.Finally,FR in the mountainous area dominated the ice weight during the rapid ice accumulation period.A numerical simulation of FR icing on wires effectively revealed the evolution of disaster-causing icing in mountainous areas.展开更多
The gap between the projected urban areas in the current trend(UAC)and those in the sustainable scenario(UAS)is a critical factor in understanding whether cities can fulfill the requirements of sustainable development...The gap between the projected urban areas in the current trend(UAC)and those in the sustainable scenario(UAS)is a critical factor in understanding whether cities can fulfill the requirements of sustainable development.However,there is a paucity of knowledge on this cutting-edge topic.Given the extensive and rapid urbanization in the United States(U.S.)over the past two centuries,accurately measuring this gap between UAS and UAC is of critical importance for advancing future sustainable urban development,as well as having significant global implications.This study finds that although the 740 U.S.cities have a large UAC in 2100,these cities will encom pass a significant gap from UAC to UAS(approximately 165,000 km2),accounting for 30%UAC at that time.The study also reveals the spatio-temporal heterogeneity of the gap.The gap initially increases before reaching a inflection point in 2090,and it disparates greatly from−100%to 240%at city level.While cities in the Northwestern U.S.maintain UAC that exceeds UAS from 2020 to 2100,cities in other regions shift from UAC that exceeds UAS to UAC that falls short of UAS.Filling the gap without additional urban growth planning could lead to a reduction of crop production ranging from 0.3%to 3%and a 0.68%loss of biomass.Hence,dynamic and forward-looking urban planning is essential for addressing the challenges of sustainable development posed by urbanization,both within the U.S.and globally.展开更多
“Go!Faster!”“Pass the ball!”Echoes of encouragement ring across the football field at Yisa Primary School,nestled high in the mountains of Butuo County in Liangshan Yi Autonomous Prefecture,southwest China’s Sich...“Go!Faster!”“Pass the ball!”Echoes of encouragement ring across the football field at Yisa Primary School,nestled high in the mountains of Butuo County in Liangshan Yi Autonomous Prefecture,southwest China’s Sichuan Province.Against a backdrop of cloudwrapped peaks,girls in jerseys dart across the turf with infectious energy.展开更多
Background:Undernutrition poses a major threat for the growth and development of children in remote island regions of Bangladesh.Methods:This study investigated the prevalence and risk predictors of undernutrition amo...Background:Undernutrition poses a major threat for the growth and development of children in remote island regions of Bangladesh.Methods:This study investigated the prevalence and risk predictors of undernutrition among children under five in the island regions of Bangladesh.A cross‐sectional study was conducted in 13 unions across two islands,with a random sample of 549 children.Results:Descriptive analyses showed that underweight(Z‐score<−2),wasting(Z‐score<−2),and stunting(Z‐score<−2)were prevalent,with rates of 36.80%,24.60%,and 47.20%,respectively.Significant predictors of underweight included a history of diarrhea(AOR=2.24,p<0.001),acute respiratory infection(ARI)(AOR=1.84,p<0.01),anemic caregivers(AOR=1.52,p<0.05),and belonging to day labor families(AOR=0.29,p<0.01).Childhood wasting was significantly associated with partial vaccination(AOR=2.84,p<0.001),large family size(AOR=1.79,p<0.05),higher birth order(AOR=0.58,p<0.05),diarrhea(AOR=3.09,p<0.001),anemic mothers(AOR=1.89,p<0.05),primary(AOR=3.35,p<0.05)and secondary(AOR=4.11,p<0.01)maternal education,and fathers working abroad(AOR=0.42,p<0.05)or as daily laborers(AOR=0.17,p<0.001).Stunting was more common among children with partial vaccination,diarrhea,and ARI,and less common among those with a history of fever or those from day laborer families.Conclusion:Overall,undernutrition among children in the island areas of Bangladesh is influenced by multiple factors,necessitating a multisectoral approach to improve their nutritional status.展开更多
This study tracked the characteristics of atmospheric wet deposition of the toxic element arsenic(As)at both urban(Guangzhou(GZ))and forested(Dinghushan Natural Reserve(DHS))sites within the Pearl River Delta(PRD)regi...This study tracked the characteristics of atmospheric wet deposition of the toxic element arsenic(As)at both urban(Guangzhou(GZ))and forested(Dinghushan Natural Reserve(DHS))sites within the Pearl River Delta(PRD)region between 2016 and 2019,examining its correlation with rainfall patterns.Additionally,by employing backward trajectory analysis and the potential source contribution function(PSCF)in conjunction with pertinent emission inventories,we pinpointed the main pathways of atmospheric arsenic transport and evaluated the emission contributions from priority source areas.The study revealed that the atmospheric arsenic wet deposition fluxes at the GZ and DHS sites exhibited a trend of increase followed by a decrease over the four-year period.Wet season deposition fluxes were more than triple those of the dry season,with urban site showing a difference of over four times.Notably,wet season As deposition at both sites was predominantly affected by heavy rainfall from marine air masses,constituting 31%of the total deposition.The predominant trajectory directions contributing to arsenic deposition at GZ and DHS were northeast(55%)and south(53%),respectively.The primary source areas for both sites were largely outside the PRD region,with the GZ site having 80%to 95%of its source area in the non-PRD region,compared to 69%to 88%at the DHS site.Furthermore,non-PRD areas contributed approximately 65%to arsenic emissions for both sites,with the industrial sector being the dominant emission source,exceeding 97%of the total emissions.展开更多
Focusing on comprehensive land consolidation in mountainous areas, this paper explores the connotation of comprehensive land consolidation and its internal logic for promoting rural revitalization. Furthermore, it elu...Focusing on comprehensive land consolidation in mountainous areas, this paper explores the connotation of comprehensive land consolidation and its internal logic for promoting rural revitalization. Furthermore, it elucidates the effectiveness and experience of mountainous area comprehensive land consolidation in the rural revitalization process by using practical cases. The aim is to provide theoretical reference and practical guidance for leveraging the role of comprehensive land consolidation in mountainous areas for rural revitalization, thereby promoting the sustainable utilization of land resources and the coordinated development of the economy and society in mountainous regions.展开更多
文摘In order to improve the added value of the main vegetable products in Qinghai Province,we researched the effect of soil selenium content on vegetable quality in selenium-enriched area of Qinghai. Through the analysis of Qinghai selenium-enriched soil selenium content and5 kinds of main vegetables corresponds to the total selenium,part of the mineral elements and soluble sugar and VC content,the effects of soil selenium levels on selenium absorption and nourishment quality of vegetables were researched. The results showed that he Qinghai selenium-enriched soil selenium content in the range of 100. 00-563. 00 μg/kg,among them,the soil samples with sufficient selenium and rich selenium accounted for 76. 53% and 18. 88%,respectively. Soil selenium content of garlic sampling area was relatively high,and soil selenium content of sugar beet sampling area was relatively low. Vegetable selenium content was in the range of 11. 00-340. 94 μg/kg,the average content of total selenium content of garlic was up to 170. 40 μg/kg,and the average content of the total selenium content of radish is 73. 00 μg/kg.90. 63% of the vegetables in the region reached the level of sufficient selenium,and 70. 31% reached the level of selenium enrichment. The average content of Ca and Mg was higher than the national average. There was no significant correlation between selenium content of soil and vegetable and nutritional quality.
基金a phased research outcome report of the Major Innovation Project of the Chinese Academy of Social Sciences,“Research on Major Issues in Improving the Mechanisms and Institutions for Integrated Urban-Rural Development”(Project No. 2024YZD008)。
文摘The promotion of rural revitalization within the ecological conservation areas(“ECAs”) requires a careful balance between ecological protection and economic development and should be guided by the principle of ecological priority. The cultivation of rural “Local Specialty Products”(“LSPs”) under a green-development framework aligns with the functional positioning of these areas, drives the revitalization of rural industries, and constitutes a fundamental strategy for addressing the unique challenges they face. Although ECAs possess inherent advantages in terms of developing LSPs, they are also confronted by multiple constraints. Accordingly, we propose development objectives that emphasize(a) driving rural industrial prosperity,(b) enhancing the appeal of agricultural heritage, and(c) ensuring inclusive prosperity in the farming communities. In selecting pathways for growth, priority should be given to improving the quality of products, fostering distinctiveness of the technologies, nurturing cultural identities, and upholding the principle of common prosperity. From a policy standpoint, the development of rural LSPs should be recognized as a key lever for advancing the comprehensiveness of rural revitalization in the ECAs. We recommend a set of supportive measures—namely, reinforcing the guidance for spatial planning, integrating the consolidation of factor inputs, and ensuring the robustness of organizational guarantees—to facilitate the high-quality development of LSPs in these areas.
基金funded by the Fundamental Research Funds for the Central Universities(No.1233300002).
文摘Background:The mobility of people in rural areas may lead to more and more left-behind children(LBC)appearing,and being an LBC brings a lot of risks to mental health,which could greatly hinder children’s development and undermine their happiness and safety in life.Previous scholars have conducted plenty of studies that focused on Chinese rural LBCs’mental health issues,such as what they exactly look like and some potential factors,but there remains a paucity of reviews about the relationship among certain mental health issues.We will try to figure out how the most common mental health issues of LBC in China’s rural areas correlate with each other,as well as their related factors.Methods:In this study,we used a systematic review approach to analyze 35 publications from Web of Science and EBSCO(to August 2025),followed by the sorting standards of Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)2020.Results:By mainly using quantitative techniques,we found that Chinese rural LBC are more likely to have mental health issues than children who have no experience of being left behind,and they often suffer from depression,social anxiety,internet addiction,and suicidal ideation.These four mental health issues share influencing factors and positively correlate with each other.We also found that Chinese rural LBCs are somewhat resilient towards the risk factors of mental health issues,and national or social policies and interventions can really help them a lot.Conclusion:For Chinese rural LBC,there are important relationships among the common psychological disorders they often suffer,along with multiple factors that affect their mental health,which can help related scholars and practitioners pay attention to such mechanisms and think more comprehensively when they try to help the children who are left behind.
基金supported by the National Key Research and Development Project[Grand No.2022YFF0802304]Key Research and Development and Transformation Project of the Xizang Autonomous Region[Grand No.XZ202501ZY0119].
文摘It is essential to understand how adaptation needs and options differ among stakeholders in protected areas(PAs)to effectively implement climate change(CC)adaptation strategies.Using the Qiangtang PA in Xizang as a case study,this research examines CC adaptation needs and options from the perspectives of stakeholders across multiple administrative levels,including provincial,prefectural,county authorities,73 protection stations,and 13364 pastoralists residing within the PA.The findings show that stakeholders at the provincial level,as well as those from the Ali and Naqu prefectures and six counties,place greater emphasis on institutional and resource-related needs than on other categories(attention score:7.0-9.3 vs.5.0-7.0).In contrast,stakeholders from the 73 protection stations prioritize technological and capacity-building needs more strongly than other types(attention score:8.0-9.0 vs.4.0-8.0).The 13364 pastoralists assign the highest importance to social needs relative to other categories(attention score:9.0-9.5 vs.3.0-8.0).Most of the eight existing protection measures were found to indirectly support broader climate adaptation efforts.In particular,protective actions addressing fire,pests,and weather-related disasters can be classified as autonomous adaptation,while other measures generate outcomes that enhance adaptation capacity under specific conditions.Adaptation options,grouped into three main types and 13 subcategories,differ across stakeholder groups,although substantial overlap exists between these options and current protective actions,including ecosystem based adaptation strategies,adaptation-related practices,autonomous adaptation measures,and emergency interventions.Overall,these findings highlight the critical role of all stakeholders-especially staff from the 73 protection stations and the 13364 pastoralists-in the effective implementation of adaptation actions within the PA.
基金supported by the National Key Research and Development Program of China (2024YFF0809304)the Third Xinjiang Scientific Expedition Program,China (2021xjkk0905)。
文摘Differentiation in housing costs reinforces the concentration of low-income groups in lowrent residential areas through residential location sorting,making the surrounding employment opportunity environment a crucial perspective for assessing urban inclusiveness.Using residential areas as the unit of analysis,this study proposed a multidimensional framework for evaluating the spatial equity of urban employment by jointly capturing disparities between opportunity supply and access across three dimensions: employment opportunity quantity,wage levels,and commuting accessibility.In addition,we compared spatial differentiation among residential area types under rentbased stratification.This study focused on Urumqi,a major city in Northwest China,and integrated multisource geospatial data for 3465 residential areas,including points of interest(POIs),online job postings,and rental data for residential areas.Empirical analyses were conducted using the Gini coefficient,location quotient,and Geographically Weighted Regression(GWR) model.The findings reveal marked disparities in employment access across ring road areas and rent-based groups.In the urban core,low-rent residential areas benefit from relatively favorable commuting conditions;however,the accessible employment opportunities are concentrated in low-wage service sectors.In the peripheral zone,low-rent residential areas face a dual disadvantage of limited nearby employment supply and longer commuting distances.Even when spatial conditions are comparable,low-rent residential areas are systematically disadvantaged relative to non-low-rent residential areas in realized access to both employment opportunity quantity and wage levels.This pattern indicated that capability constraints impede the conversion of spatial resources into effective access.Further analyses highlight housing costs,infrastructure quality,and residential location as key associated factors.The findings underscored the importance of coordinated,targeted policies in affordable housing delivery,the spatial distribution of employment opportunities,and improvements in transport accessibility to promote urban spatial justice.
基金supported by the Natural Science Foundation of Fujian Province(2023J01434)the Science and Technology Innovation Special Fund Project of Fujian Agriculture and Forestry University(KFb22028XA)。
文摘Addressing the widespread issues of internal fragmentation within protected areas and the neglect of surrounding critical habitat networks,this study aims to develop an assessment framework for the precise identification and remediation of regional conservation gaps.To this end,we introduce the Framework for Conservation Priority Identification(FCPI).The framework integrates Morphological Spatial Pattern Analysis(MSPA),the Remote Sensing Ecological Index(RSEI),Circuit Theory,and the Minimum Cumulative Resistance(MCR)model to formulate a multidimensional conservation priority index.This index facilitates the identification of critical ecological network components and enables the dynamic prioritization of conservation efforts.A case study of Fuzhou City from 2014 to 2020 reveals that despite an overall improvement in regional environmental quality,the functionality of core ecological sources has markedly declined.Between 2014 and 2020,the number of ecological sources grew by 76.9%,yet their total area shrank by 13.9%.Concurrently,the number of ecological corridors rose from 27 to 53,extending their total length by 380.23 km,which indicates an intensifying trend of habitat fragmentation.Furthermore,a significant number of crucial ecological network nodes,particularly within Minhou County,lie explicitly outside the existing protected area system.This confirms the presence of conservation gaps and unveils the spatiotemporal dynamics of shifting conservation priorities.The research validates that the proposed FCPI can effectively diagnose the dynamic deficiencies within conservation systems.It offers scientific decisionsupport for local governments,facilitating a transition from isolated conservation efforts towards systematic and comprehensive ecological network governance.
基金supported by the Scientific Research Foundation supported by Yunnan Agricultural University(A3012024035044)International Cooperation and Exchange of the National Natural Science Foundation of China(No.42361144885).
文摘The establishment of plantations has become a critical approach for reducing greenhouse gas emissions,particularly in fragile environments with carbon sequestration potential.In karst areas,plantations based on fastgrowing afforestation species made significant contributions to enhancing carbon sequestration.However,the impact of understory vegetation on carbon accumulation remains unclear.Especially,the carbon accumulation associated with litter produced during the replacement of understory species receives insufficient attention,which leads to the neglect of the carbon sequestration potential in plantations of karst areas.Leaf is a crucial organ that links the litter production.To explore how leaf traits adapt to competitive environments and drive litter carbon accumulation during understory species replacement,this study observed leaf traits and litter carbon content changes in three types of plantations in the Liujiang River Basin,a typical karst area.A total of 37 sampling plots were selected for field investigation over a twoyear period.Leaf traits,species diversity,vegetation coverage,and litter carbon characteristics in understory vegetation were measured.Variance analysis,allometric equations,and path analysis were used for data analysis.The results showed that most understory species adopted a biomass conservation strategy under high-coverage conditions(>44.27%)and expanded competitive leaf area under low-coverage conditions(<44.27%).However,Bidens pilosa and Miscanthus floridulus exhibited strong competitiveness during understory species replacement.They showed an expansion of competitive leaf area under high-coverage conditions.This competitive strategy reduced species diversity and community specific leaf area.But the rapid expansion of Bidens pilosa and Miscanthus floridulus increased understory vegetation coverage,and their increased specific leaf area facilitated leaf shedding,resulting in significant litter weight accumulation(P<0.05),thereby enhancing litter carbon content per unit area.These competitive strategies were key driving factors for the increase in litter carbon content per square meter,which reached a maximum of 49.6% higher than that in natural grasslands.And the maximum increase in litter carbon accumulation derived from understory vegetation reached 3.37 times from 2023 to 2024 in plantations.In the understory vegetation of plantations,the competitive strategies reflected by leaf adaptation of key competitive species are critical factors influencing litter carbon accumulation.Future research could deeply explore the carbon sequestration effects resulting from the dynamic changes in competition within the understory vegetation of plantations.
基金funded by Project of Scientific Research Business Expenses of Provincial Scientific Research Institutes in Heilongjiang Province(No.CZKYF2023-1-B024)Heilongjiang Academy of Sciences Dean Fund Project(No.YZ2022ZR02)+1 种基金the Science and Technology Basic Resources Investigation Program of China(No.2019FY100500)the Fundamental Research Funds for the Central Universities(No.2572023CT11).
文摘The study aimed at predicting potential suitable areas with national key reserve Orchidaceae plants in Heilongjiang province and conducive to plant protection.The distribution point data of six Orchidaceae plants and 19 bioclimatic variables were selected,and the environmental factors required for modeling were screened out by pearson correlation analysis and variance inflation factor(VIF)analysis.The potential suitable areas of Orchidaceae plants were predictat present and under different climate scenarios in 2090s by using geographic information system(GIS)and Maximum Entropy Model(MaxEnt).And then evaluated the prediction accuracy of the MaxEnt model using the AUC value,the TSS value and the Kappa value.The results showed that:1)The area under curve(AUC)values,true skill statistics(TSS)values and KAPPA values predicted by MaxEnt model were separately above 0.9,0.85 and 0.75.2)Under the climate scenario at present,the total suitable area of Orchidaceae plants was about 9.61×10^(6)km^(2),which was mainly distributed in Heilongjiang province.Among them,the high-suitable area of Cypripedium shanxiense S.C.Chen was the largest,the non-suitable area of Cypripedium guttatum Sw was the largest.3)Under different climate scenarios in 2090s,the total suitable area was slightly increasing(9.62×10^(6)km^(2)).Among them,Cypripedium shanxiense S.C.Chen and Gastrodiae Rhizoma both showed the trend of expansion to the southwest,China,and the suitable areas expanded significantly.Comprehensive factor analysis showed that temperature and precipitation were the main bioclimatic variables of suitable areas distribution,and the low emission scenario(SSP 2-4.5)will be more conducive to the survival of Orchidaceae plants.
基金supported by the key technology project of China Southern Power Grid Corporation(GZKJXM20220041)partly by the National Key Research and Development Plan(2022YFE0205300).
文摘This paper presents an optimal operation method for embedded DC interconnections based on low-voltage AC/DC distribution areas(EDC-LVDA)under three-phase unbalanced compensation conditions.It can optimally determine the transmission power of the DC and AC paths to simultaneously improve voltage quality and reduce losses.First,considering the embedded interconnected,unbalanced power structure of the distribution area,a power flow calculation method for EDC-LVDA that accounts for three-phase unbalanced compensation is introduced.This method accurately describes the power flow distribution characteristics under both AC and DC power allocation scenarios.Second,an optimization scheduling model for EDC-LVDA under three-phase unbalanced conditions is developed,incorporating network losses,voltage quality,DC link losses,and unbalance levels.The proposed model employs an improved particle swarm optimization(IPSO)two-layer algorithm to autonomously select different power allocation coefficients for the DC link and AC section under various operating conditions.This enables embedded economic optimization scheduling while maintaining compensation for unbalanced conditions.Finally,a case study based on the IEEE 13-node system for EDC-LVDA is conducted and tested.The results show that the proposed optimal operation method achieves a 100%voltage compliance rate and reduces network losses by 13.8%,while ensuring three-phase power balance compensation.This provides a practical solution for the modernization and upgrading of low-voltage power grids.
基金the National Key Research and Development Program of China (Grant No.2022YFF0711400)the National Space Science Data Center Youth Open Project (Grant No. NSSDC2302001)
文摘Impact craters are important for understanding the evolution of lunar geologic and surface erosion rates,among other functions.However,the morphological characteristics of these micro impact craters are not obvious and they are numerous,resulting in low detection accuracy by deep learning models.Therefore,we proposed a new multi-scale fusion crater detection algorithm(MSF-CDA)based on the YOLO11 to improve the accuracy of lunar impact crater detection,especially for small craters with a diameter of<1 km.Using the images taken by the LROC(Lunar Reconnaissance Orbiter Camera)at the Chang’e-4(CE-4)landing area,we constructed three separate datasets for craters with diameters of 0-70 m,70-140 m,and>140 m.We then trained three submodels separately with these three datasets.Additionally,we designed a slicing-amplifying-slicing strategy to enhance the ability to extract features from small craters.To handle redundant predictions,we proposed a new Non-Maximum Suppression with Area Filtering method to fuse the results in overlapping targets within the multi-scale submodels.Finally,our new MSF-CDA method achieved high detection performance,with the Precision,Recall,and F1 score having values of 0.991,0.987,and 0.989,respectively,perfectly addressing the problems induced by the lesser features and sample imbalance of small craters.Our MSF-CDA can provide strong data support for more in-depth study of the geological evolution of the lunar surface and finer geological age estimations.This strategy can also be used to detect other small objects with lesser features and sample imbalance problems.We detected approximately 500,000 impact craters in an area of approximately 214 km2 around the CE-4 landing area.By statistically analyzing the new data,we updated the distribution function of the number and diameter of impact craters.Finally,we identified the most suitable lighting conditions for detecting impact crater targets by analyzing the effect of different lighting conditions on the detection accuracy.
文摘We investigated the impact of convexity and isoperimetric deficits on the accuracy of sectional area estimates of tree stems using traditional methods(caliper,tape,formulas based on stem diameter and circumference).In two complementary experiments,the use of photographs to estimate cross-sectional areas was first validated,then the use of a caliper and diameter tape was computer-simulated.The results indicated that the photographic method offers high precision,with mean relative errors below 0.1%,minimal deviation,and no significant bias,and the traditional methods led to substantial and systematic errors,with deviations from circularity and convexity significantly increasing the errors in area estimation.
基金supported by the National Natural Science Foundation of China(32302774)Beijing Innovation Consortium of Agriculture Research System(BAIC04)+1 种基金China Agriculture Research System(CARS-40)the Agricultural Science and Technology Innovation Program of the Feed Research Institute of the Chinese Academy of Agricultural Sciences(CAASIFR-ZDRW202402).
文摘Background Organic selenium(Se)has gained recognition in poultry nutrition as a feed additive to boost production and Se deposition in eggs and tissues,owing to its high bioavailability,efficient tissue accumulation and minimal toxicity.Selenium-enriched yeast(SeY)is a well-established source,while selenium-enriched lactobacilli(SeL),a newer alternative,offers the added benefits of probiotics.This study examined the effects of SeY and SeL on egg quality,antioxidant capacity,Se deposition,and gut health in laying hens.After a two-week pre-treatment with a Sedeficient diet(SeD),450 Hy-Line Brown laying hens(30-week-old)were assigned into five dietary groups with six replicates of 15 hens each.The groups included a SeD,SeD supplemented with 1.5 mg Se/kg from SeY(SeY15),or 1.5,3.0,and 6.0 mg Se/kg from SeL(SeL15,SeL30,SeL60).The feeding trial lasted for 12 weeks.Results SeY15 and SeL15 improved the feed-to-egg ratio(P<0.05)in the latter stages.Haugh units were significantly increased(P<0.05)in the SeY15 and SeL30 groups,while darker yolk color(P<0.05)was observed in the SeY15,SeL15,and SeL60 groups.All Se-supplemented diets increased Se content in whole eggs,albumen,and yolk(P<0.05),while SeL groups showed a dose-dependent effect.Antioxidant enzyme activities increased,and MDA content decreased in the serum(P<0.05),with SeY15 showing the highest GSH-Px levels(P<0.05).SeL60 increased serum alkaline phosphatase and aspartate transaminase,and distorted the liver architecture(P<0.05).Se-diets reduced concentrations of reactive oxygen species(ROS)in the ileum and liver(P<0.05).SeL15 improved the ileal villus height-tocrypt depth ratio(P<0.05).SeY15 and/or SeL15 up-regulated TXNRD1 and SEPHS1 mRNA while down-regulating SCLY expression in the liver.SeY15 altered ileal microbiota by increasing both beneficial and pathogenic bacteria,whereas SeL15 predominantly boosted beneficial bacteria.Conclusion SeL integrates the antioxidant properties of organic Se with the probiotic benefits on gut health,resulting in a performance-enhancing effect comparable to that of SeY.However,high SeL level(6.0 mg Se/kg)compromised productivity and metabolic functions while enhancing Se deposition.
基金supported by the Key Program of the National Natural Science Foundation of China(Grant No.41931293)the National Natural Science Foundation of China(Grant No.42271275).
文摘The rapid population and land urbanization not only promoted economic development but also affected the ecosystem service value(ESV).In the context of new-type urbanization and green development,it’s essential to investigate the impacts of urbanization on ESV in China.However,a comprehensive and dynamic framework to reveal the relationship between ESV and urbanization processes is lacking.This study adopted multi-source datasets to portray China’s urbanization process by integrating population,land,and economic urbanization,eval-uated the ESV changes of 10 categories by gross ecosystem product(GEP)methods,and explored ESV changes within different urbanization scales and speeds.The results showed rapid urbanization in the population,land,and economic dimensions in China,with a faster process of economic urbanization.The ESV also exhibited an increasing trend,with higher levels in the southeastern coastal regions and lower levels in the northwestern regions.Urbanization had positive impacts on ESV across various research units,but the ESV exhibited heteroge-neous changes across different urbanization scales,speeds,and their interactive effects.The response of ESV to dynamic urbanization processes was influenced by socio-economic,ecological,and policy factors;it is essential to combine targeted measures with general ecological product value realization methods in each unit to maximize social-economic-ecological benefits.
基金supported by the Natural Science Foundation of Henan Province(252300421290)the National Natural Science Foundation of China(41771438)+1 种基金the Program for Innovative Research Team(in Science and Technology)of Henan University(22IRTSTHN010)the Postgraduate Education Reform and Quality Improvement Project of Henan Province(HNYJS2020JD14).
文摘Soil moisture(SM)is a critical variable in terrestrial ecosystems,especially in arid and semi-arid areas where water sources are limited.Despite its importance,understanding the spatiotemporal variations and influencing factors of SM in these areas remains insufficient.This study investigated the spatiotemporal variations and influencing factors of SM in arid and semi-arid areas of China by utilizing the extended triple collation(ETC),Mann-Kendall test,Theil-Sen estimator,ridge regression analysis,and other relevant methods.The following findings were obtained:(1)at the pixel scale,the long-term monthly SM data from the European Space Agency Climate Change Initiative(ESA CCI)exhibited the highest correlation coefficient of 0.794 and the lowest root mean square error(RMSE)of 0.014 m^(3)/m^(3);(2)from 2000 to 2022,the study area experienced significant increase in annual average SM,with a rate of 0.408×10^(-3)m^(3)/(m^(3)•a).Moreover,higher altitudes showed a notable upward trend,with SM increasing rates at 0.210×10^(-3)m^(3)/(m^(3)•a)between 1000 and 2000 m,0.530×10^(-3)m^(3)/(m^(3)•a)between 2000 and 4000 m,and 0.760×10^(-3)m^(3)/(m^(3)•a)at altitudes above 4000 m;(3)land surface temperature(LST),root zone soil moisture(RSM)(10-40 cm depth),and normalized difference vegetation index(NDVI)were identified as the primary factors influencing annual average SM,which accounted for 34.37%,24.16%,and 22.64%relative contributions,respectively;and(4)absolute contribution of LST was more significant in subareas at higher altitudes,with average absolute contributions of 0.800×10^(-3)m^(3)/(m^(3)•a)between 2000 and 4000 m and 0.500×10^(-2) m^(3)/(m^(3)•a)above 4000 m.This study reveals the spatiotemporal variations and main influencing factors of SM in Chinese arid and semi-arid areas,highlighting the more pronounced absolute contribution of LST to SM in high-altitude areas,providing valuable insights for ecological research and water resource management in these areas.
基金funded by the National Natural Science Foundation of China(Grant No.42325503)the Hubei Provincial Natural Science Foundation and the Meteorological Innovation and Development Project of China(Grant Nos.2023AFD096 and 2022CFD122)+1 种基金the Natural Science Foundation of Wuhan(Grant No.2024020901030454)the Beijige Foundation of NJIAS(Grant No.BJG202304)。
文摘Based on comprehensive observations of 20 wire icing events during winter from 2019 to 2021,we investigated the characteristics of the icing properties,the atmospheric boundary layer structure,the raindrop size distribution,and their associated effects on the ice accretion mechanism in the mountainous region of Southwest China.The maximum ice weight was positively correlated with the duration of ice accretion in the mountainous area.The duration of precipitation accounted for less than 20%of the icing period in the mountainous area,with solid-phase hydrometeors being predominant.Icing events,dominated by freezing rain(FR)and mixed rain–graupel(more than 70%),were characterized by glaze or highdensity mixed icing.The relationship between the melting energy and refreezing energy reflected the distribution characteristics of the proportion of FR under mixed-phase precipitation.The intensity of the warm layer and the dominant precipitation phase significantly affected the variations in the microphysical properties of FR.The melting of large dry snowflakes significantly contributed to FR in the mountainous areas,resulting in smaller generalized intercepts and larger mass-weighted mean diameters in the presence of a stronger warm layer.Under a weaker warm layer,the value of the massweighted mean diameter was significantly smaller because of the inability of large solid particles to melt.Finally,FR in the mountainous area dominated the ice weight during the rapid ice accumulation period.A numerical simulation of FR icing on wires effectively revealed the evolution of disaster-causing icing in mountainous areas.
基金supported by the National Natural Science Foun-dation of China(Grants No.42330103,42271469)the Ningbo Science and Technology Bureau(Grant No.2022Z081).
文摘The gap between the projected urban areas in the current trend(UAC)and those in the sustainable scenario(UAS)is a critical factor in understanding whether cities can fulfill the requirements of sustainable development.However,there is a paucity of knowledge on this cutting-edge topic.Given the extensive and rapid urbanization in the United States(U.S.)over the past two centuries,accurately measuring this gap between UAS and UAC is of critical importance for advancing future sustainable urban development,as well as having significant global implications.This study finds that although the 740 U.S.cities have a large UAC in 2100,these cities will encom pass a significant gap from UAC to UAS(approximately 165,000 km2),accounting for 30%UAC at that time.The study also reveals the spatio-temporal heterogeneity of the gap.The gap initially increases before reaching a inflection point in 2090,and it disparates greatly from−100%to 240%at city level.While cities in the Northwestern U.S.maintain UAC that exceeds UAS from 2020 to 2100,cities in other regions shift from UAC that exceeds UAS to UAC that falls short of UAS.Filling the gap without additional urban growth planning could lead to a reduction of crop production ranging from 0.3%to 3%and a 0.68%loss of biomass.Hence,dynamic and forward-looking urban planning is essential for addressing the challenges of sustainable development posed by urbanization,both within the U.S.and globally.
文摘“Go!Faster!”“Pass the ball!”Echoes of encouragement ring across the football field at Yisa Primary School,nestled high in the mountains of Butuo County in Liangshan Yi Autonomous Prefecture,southwest China’s Sichuan Province.Against a backdrop of cloudwrapped peaks,girls in jerseys dart across the turf with infectious energy.
文摘Background:Undernutrition poses a major threat for the growth and development of children in remote island regions of Bangladesh.Methods:This study investigated the prevalence and risk predictors of undernutrition among children under five in the island regions of Bangladesh.A cross‐sectional study was conducted in 13 unions across two islands,with a random sample of 549 children.Results:Descriptive analyses showed that underweight(Z‐score<−2),wasting(Z‐score<−2),and stunting(Z‐score<−2)were prevalent,with rates of 36.80%,24.60%,and 47.20%,respectively.Significant predictors of underweight included a history of diarrhea(AOR=2.24,p<0.001),acute respiratory infection(ARI)(AOR=1.84,p<0.01),anemic caregivers(AOR=1.52,p<0.05),and belonging to day labor families(AOR=0.29,p<0.01).Childhood wasting was significantly associated with partial vaccination(AOR=2.84,p<0.001),large family size(AOR=1.79,p<0.05),higher birth order(AOR=0.58,p<0.05),diarrhea(AOR=3.09,p<0.001),anemic mothers(AOR=1.89,p<0.05),primary(AOR=3.35,p<0.05)and secondary(AOR=4.11,p<0.01)maternal education,and fathers working abroad(AOR=0.42,p<0.05)or as daily laborers(AOR=0.17,p<0.001).Stunting was more common among children with partial vaccination,diarrhea,and ARI,and less common among those with a history of fever or those from day laborer families.Conclusion:Overall,undernutrition among children in the island areas of Bangladesh is influenced by multiple factors,necessitating a multisectoral approach to improve their nutritional status.
基金supported by the National Natural Science Foundation of China(Nos.42121004,42275107,and 42077205)the National Key Research and Development Plan(No.2023YFC3706202)+1 种基金the Foundational and Applied Basic Research in Guangzhou in 2023(No.2023A04J0251)the Special Fund Project for Science and Technology Innovation Strategy of Guangdong Province(No.2019B121205004)。
文摘This study tracked the characteristics of atmospheric wet deposition of the toxic element arsenic(As)at both urban(Guangzhou(GZ))and forested(Dinghushan Natural Reserve(DHS))sites within the Pearl River Delta(PRD)region between 2016 and 2019,examining its correlation with rainfall patterns.Additionally,by employing backward trajectory analysis and the potential source contribution function(PSCF)in conjunction with pertinent emission inventories,we pinpointed the main pathways of atmospheric arsenic transport and evaluated the emission contributions from priority source areas.The study revealed that the atmospheric arsenic wet deposition fluxes at the GZ and DHS sites exhibited a trend of increase followed by a decrease over the four-year period.Wet season deposition fluxes were more than triple those of the dry season,with urban site showing a difference of over four times.Notably,wet season As deposition at both sites was predominantly affected by heavy rainfall from marine air masses,constituting 31%of the total deposition.The predominant trajectory directions contributing to arsenic deposition at GZ and DHS were northeast(55%)and south(53%),respectively.The primary source areas for both sites were largely outside the PRD region,with the GZ site having 80%to 95%of its source area in the non-PRD region,compared to 69%to 88%at the DHS site.Furthermore,non-PRD areas contributed approximately 65%to arsenic emissions for both sites,with the industrial sector being the dominant emission source,exceeding 97%of the total emissions.
文摘Focusing on comprehensive land consolidation in mountainous areas, this paper explores the connotation of comprehensive land consolidation and its internal logic for promoting rural revitalization. Furthermore, it elucidates the effectiveness and experience of mountainous area comprehensive land consolidation in the rural revitalization process by using practical cases. The aim is to provide theoretical reference and practical guidance for leveraging the role of comprehensive land consolidation in mountainous areas for rural revitalization, thereby promoting the sustainable utilization of land resources and the coordinated development of the economy and society in mountainous regions.
