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How does urbanization evolve heterogeneously in urbanized,urbanizing,and rural areas of China?Insights from ecosystem service value 被引量:2
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作者 Yikun Zhang Yongsheng Wang 《Geography and Sustainability》 2025年第3期117-128,共12页
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
关键词 URBANIZATION Urban-rural areas Ecosystem service value Social-economic-ecological benefits China
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Causes and health risk assessment of fluorine in the Red bed groundwater and adjacent geothermal water of the Guang'an Area,Southwest China 被引量:2
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作者 Yu-xiang Shao Wei Zhang +6 位作者 Wen-bin Chen Li Chen Jian Li Guang-long Tian Li-cheng Quan Bu-qingYan Yu-jie Liu 《Journal of Groundwater Science and Engineering》 2025年第2期116-132,共17页
Understanding the levels,causes,and sources of fluoride in groundwater is critical for public health,effective water resource management,and sustainable utilization.This study employs multivariate statistical methods,... Understanding the levels,causes,and sources of fluoride in groundwater is critical for public health,effective water resource management,and sustainable utilization.This study employs multivariate statistical methods,hazard quotient assessment,and geochemical analyses,such as mineral saturation index,ionic activities,and Gibbs diagrams,to investigate the hydrochemical characteristics,causes,and noncarcinogenic risks of fluoride in Red bed groundwater and geothermal water in the Guang'an area and neighboring regions.Approximately 9%of the Red bed groundwater samples contain fluoride concentrations exceeding 1 mg·L^(-1).The predominant water types identified are Cl-Na and HCO_(3)-Na,primarily influenced by evapotranspiration.Low-fluoride groundwater and high-fluoride geothermal water exhibit distinct hydrochemical types HCO_(3)-Ca and SO_(4)-Ca,respectively,which are mainly related to the weathering of carbonate,sulfate,and fluorite-containing rocks.Correlation analysis reveals that fluoride content in Red bed groundwater is positively associated with Na^(+),Cl^(-),SO_(4)^(2-),and TDS(r^(2)=0.45-0.64,p<0.01),while in geothermal water,it correlates strongly with pH,K^(+),Ca^(2+),and Mg^(2+)(r^(2)=0.52-0.80,p<0.05).Mineral saturation indices and ionic activities indicate that ion exchange processes and the dissolution of minerals such as carbonatite and fluorite are important sources of fluoride in groundwater.The enrichment of fluorine in the Red bed groundwater is linked to evaporation,cation exchange and dissolution of fluorite,caused by the lithologic characteristics of the red bed in this area.However,it exhibits minimal correlation with the geothermal water in the adjacent area.The noncarcinogenic health risk assessment indicates that 7%(n=5)of Red bed groundwater points exceed the fluoride safety limit for adults,while 12%(n=8)exceed the limit for children.These findings underscore the importance of avoiding highly fluoridated red bed groundwater as a direct drinking source and enhancing groundwater monitoring to mitigate health risks associated with elevated fluoride levels. 展开更多
关键词 Guang'an area Red bed groundwater Geothermal water Fluoride contamination CAUSES Health risk assessment
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Study on cook-off characteristics and thermal safety venting area of RBOE charge 被引量:1
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作者 Kebin Zhang Wenbin Li +3 位作者 Changfang Zhao Zhifang Wei Shuxia Zhang Jin Li 《Defence Technology(防务技术)》 2025年第1期271-287,共17页
RBOE is a new type of DNAN-based high-energy melt-cast mixed explosive,whose safety under thermal stimulation is significantly affected by heating conditions and venting area of the warhead.Based on the thermal decomp... RBOE is a new type of DNAN-based high-energy melt-cast mixed explosive,whose safety under thermal stimulation is significantly affected by heating conditions and venting area of the warhead.Based on the thermal decomposition reaction characteristics and combustion characteristics of each component of RBOE explosive,the cook-off calculation models of RBOE warhead before and after ignition were established.In addition,closed and vented warheads were designed,as well as fast and slow cook-off test devices.The cook-off characteristics and thermal safety venting area of RBOE warhead were extensively studied.The results showed that the closed RBOE warhead underwent deflagration reaction under both slow and fast cook-off conditions.The calculation result of the shell wall temperature before slow cookoff ignition response of the warhead was 454.06 K,with an error of+1.75%compared to the test result of462.15 K,and the temperature rise rate calculated was in good agreement with the test.The calculated ignition time of RBOE warhead under fast cook-off was 161 s,with an error of+8.8%compared to the test result of 148 s,which verified the accuracy of cook-off model of RBOE warhead before ignition.According to the cook-off calculation model of the warhead after ignition and cook-off test of the vented warhead,it was determined that the thermal safety venting area was 1124.61 mm^(2)for fast cook-off and 530.66 mm~2 for slow cook-off,effectively preventing the reaction of warhead above combustion.Therefore,this study provides a scientific basis for the thermal safety design and evaluation of insensitive warheads. 展开更多
关键词 RBOE explosive Cook-off model Temperature distribution Pressure growth Venting area
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Macro-and Microphysical Characteristics of Freezing Rain and Their Impacts on Wire Icing Mechanisms in the Southwestern Mountainous Areas of China 被引量:1
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作者 Yue ZHOU Chunsong LU +3 位作者 Jingjing Lü Xiaoyun SUN Lingli ZHOU Hui XIAO 《Advances in Atmospheric Sciences》 2025年第8期1620-1635,共16页
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
关键词 freezing rain wire icing macro-and microphysical characteristics mountainous area
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Accumulation characteristics and fate modeling of phthalic acid esters in surface water from the Three Gorges Reservoir area,China 被引量:1
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作者 Shuai Sun Bing Zhang +6 位作者 Junjie Hu Wen Gu Zhen Wang Deling Fan Feng Ge Lili Shi Lei Wang 《Journal of Environmental Sciences》 2025年第3期46-56,共11页
Phthalic acid esters(PAEs)are a group of compounds widespread in the environment.To investigate the occurrence and accumulation characteristics of PAEs,surface water samples were collected from the Three Gorges Reserv... Phthalic acid esters(PAEs)are a group of compounds widespread in the environment.To investigate the occurrence and accumulation characteristics of PAEs,surface water samples were collected from the Three Gorges Reservoir area,China.The total concentrations of∑_(11)analyzed PAEs(11PAEs)in the collected water samples ranging from 197.7 to 1,409.3 ng/L(mean±IQR:583.1±308.4 ng/L).While DEHP was the most frequently detected PAE,DnBP and DnNP were the most predominant PAEs in the analyzed water samples with a mean contribution of 63.3%of the∑_(11)PAEs.The concentrations of the∑_(11)PAEs in the water samples from the upper reaches of the Yangtze River were significantly higher than those from themiddle reaches.To better understand the transport and fate of the PAEs,seven detected PAEs were modeled by Quantitative Water Air Sediment Interaction(QWASI).The simulated and measured values were close for most PAEs,and differences are within one order of magnitude even for the worst one.For all simulated PAEs,water and particle inflow were main sources in the reservoir,whereas water outflow and degradation in water were important removal pathways.The contribution ratios of different sources/losses varied fromPAEs,depending on their properties.The calculated risk quotients of DnNP in the Three Gorges Reservoir area whether based onmonitoring or simulating results were all far exceeded the safety threshold value,implying the occurrence of this PAE compound may cause potential adverse effects for the aquatic ecology of the Three Gorges Reservoir area. 展开更多
关键词 Phthalic esters Surface water Transport and fate Three Gorges Reservoir area Risk assessment
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Variations of soil moisture and its influencing factors in arid and semi-arid areas,China 被引量:1
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作者 NIU Jiqiang LIU Zijian +5 位作者 CHEN Feiyan LIU Gangjun ZHOU Junli ZHOU Peng LI Hongrui LI Mengyang 《Journal of Arid Land》 2025年第5期624-643,共20页
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
关键词 soil moisture arid and semi-arid areas remote sensing extended triple collation ridge regression analysis
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Analysis of the Physical State and Operation of Hydraulic Infrastructure in the Konni Irrigated Area before Rehabilitation
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作者 Aboubacar Yerima Bako Djibo Illa Salifou Guero Yadji 《Open Journal of Applied Sciences》 2025年第1期127-136,共10页
In Niger, irrigated agriculture constitutes the main alternative for meeting family needs. It is within this framework that the state and its partners have adopted strategies to promote irrigated production sites. Thi... In Niger, irrigated agriculture constitutes the main alternative for meeting family needs. It is within this framework that the state and its partners have adopted strategies to promote irrigated production sites. This study was carried out on the Konni irrigated perimeter, the objective of which is to analyze the physical state of hydraulic infrastructures and their operation before the rehabilitation of the said perimeter. The methodology adopted consisted, first of all, of documentary research focused on data relating to this scope and our theme to properly guide the collection of data in the field. The field phase was then followed with an observation of hydraulic infrastructures one by one in order to assess their condition. Thus, the collected data was processed and analyzed. The results of this study show a notable deterioration of hydraulic infrastructure which affected the operating yield of the study area, with the development of barely 700 ha out of 1226 ha planned by the basic study for off-season production (57%). Bathymetric measurements showed that the volume of sediment that accumulated in the Zongo Dam is 1.2 million m3, which reduces its initial capacity from 12 million m3 to 10.8 million m3 after 43 years of service. The expansion joints of the feed canal are all in poor condition. 90% of the total length of the tertiary canals are degraded, 82.32% of the panels of the main canal C are degraded and 17.68% are cracked. All crossing structures are blocked between the RN1 and the Zongo dam. Based on this critical situation, it would be essential to consider rehabilitation work on all infrastructure in order to restore the hydraulic and even agronomic performance of the Konni irrigated area. 展开更多
关键词 Irrigated area DAMS REHABILITATION Work Monitoring Distribution Network Konni
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Compatible basal area models for live and dying trees using diffusion processes
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作者 Petras Rupšys 《Journal of Forestry Research》 2025年第3期120-138,共19页
Models that predict a forest stand’s evolution are essential for developing plans for sustainable management.A simple mathematical framework was developed that con-siders the individual tree and stand basal area unde... Models that predict a forest stand’s evolution are essential for developing plans for sustainable management.A simple mathematical framework was developed that con-siders the individual tree and stand basal area under random resource competition and is based on two assumptions:(1)a sigmoid-type stochastic process governs tree and stand basal area dynamics of living and dying trees,and(2)the total area that a tree may potentially occupy determines the number of trees per hectare.The most effective method to satisfy these requirements is formalizing each tree diameter and potentially occupied area using Gompertz-type stochastic differential equations governed by fixed and mixed-effect parameters.Data from permanent experimental plots from long-term Lithuania experiments were used to construct the tree and stand basal area models.The new models were relatively unbiased for live trees of all species,including silver birch(Betula pen-dula Roth)and downy birch(Betula pubescens Ehrh.),[spruce(Picea abies),and pine(Pinus sylvestris)].Less reliable predic-tions were made for the basal area of dying trees.Pines gave the highest accuracy prediction of mean basal area among all live trees.The mean basal area prediction for all dying trees was lower than that for live trees.Among all species,pine also had the best average basal area prediction accuracy for live trees.Newly developed basal area growth and yield models can be recommended despite their complex formulation and implementation challenges,particularly in situations when data is scarce.This is because the newly observed plot provides sufficient information to calibrate random effects. 展开更多
关键词 Basal area Occupied area Stochastic process Probability distribution
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Shrub height and crown projection area are effective predictors in aboveground biomass models for multi-stemmed European hazel
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作者 Jozef Pajtík Bohdan Konôpka +2 位作者 Ivan Barka Katarína Merganičová Martin Lukac 《Forest Ecosystems》 2025年第3期561-569,共9页
While numerous allometric models exist for estimating biomass in trees with single stems,models for multi-stemmed species are scarce.This study presents models for predicting aboveground biomass(AGB)in European hazel(... While numerous allometric models exist for estimating biomass in trees with single stems,models for multi-stemmed species are scarce.This study presents models for predicting aboveground biomass(AGB)in European hazel(Corylus avellana L.),growing in multi-stemmed shrub form.We measured the size and harvested the biomass of 30 European hazel shrubs,drying and weighing their woody parts and leaves separately.AGB(dry mass)and leaf area models were established using a range of predictors,such as the upper height of the shrub,number of shoots per shrub,canopy projection area,stem base diameter of the thickest stem,and the sum of cross-sectional areas of all stems at the stem base.The latter was the best predictor of AGB,but the most practically useful variables,defined as relatively easy to measure by terrestrial or aerial approaches,were the upper height of the shrub and the canopy projection area.The leaf biomass to AGB ratio decreased with the shrub's height.Specific leaf area of shaded leaves increases with shrub height,but that of leaves at the top of the canopy does not change significantly.Given that the upper shrub height and crown projection of European hazel can be estimated using remote sensing approaches,especially UAV and LIDAR,these two variables appear the most promising for effective measurement of AGB in hazel. 展开更多
关键词 Aboveground biomass model Biomass partitioning Shrub upper height Canopy projection area Leaf area index
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We Examined about Soil and Agrochemical Factors on Tomatoes Planting in the Mount Area
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作者 An Nguyen Thi Ngoc Trang Huynh Nguyen Thuy 《Journal of Environmental Science and Engineering(A)》 2025年第6期276-280,共5页
Ta Ngao is the local name in Loc Thanh Village,Bao Lam District,Lam Dong Province.This district is a place that has rich mineral resources in the province with 10%in the total mineral resource value of Southeast.With ... Ta Ngao is the local name in Loc Thanh Village,Bao Lam District,Lam Dong Province.This district is a place that has rich mineral resources in the province with 10%in the total mineral resource value of Southeast.With a waterfall of 7 stages,it seems to be one beautiful site,a big resource for hydroelectricity generation.Besides,there are some natural landscapes and human resource for many forms;this is a conversing place of many peoples;therefore,we have a strong potential to develop the tourism.It is a wild area,everyone plants a little;therefore,here,it has not vegetables.The soil and the efficiency of the trees do not care.Here,we examined the heavy metals on the tomatoes and we studied fertilizers,and we want to improve the soil,to serve the product for the people better. 展开更多
关键词 FERTILIZER TOMATO heavy metal SOIL area
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Field of Dreams--Football is providing a path to a brighter future for young girls from remote areas of China
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作者 LIU CHANG 《ChinAfrica》 2025年第6期56-58,共3页
“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
关键词 GIRLS remote areas EDUCATION FOOTBALL China football field FUTURE
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Training to Improve Community’s Knowledge, Attitude, Motivation and Behavior Related to the Building of Family Toilets in the Coastal Area
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作者 Edy Sabara Bakhrani Abdul Rauf +2 位作者 Desy Safitri Arita Marini Mithen Lullulangi 《Journal of Environmental & Earth Sciences》 2025年第4期193-202,共10页
The purpose of this study was to examine the knowledge,attitude,motivation and behavior of the community before and after the experiment,and also to determine the effect of the experiment on increasing knowledge,attit... The purpose of this study was to examine the knowledge,attitude,motivation and behavior of the community before and after the experiment,and also to determine the effect of the experiment on increasing knowledge,attitude,motivation,and behavior related to the construction of family toilets in coastal areas.The study was conducted in Pangkep and Maros Regencies.Atotal of 50 heads of families were selected as participants using the purposive sampling method.25 participants became the experimental group and 25 people became the control group.The research variables included knowledge,attitudes,motivation,and behavior of the community in building family toilets before and after the experiment.Data collection through tests,questionnaires,and observations to each participant.The research instruments were knowledge tests,questionnaires,and observations.Data analysis used descriptive and inferential statistical analysis,with the t-test.The results of the study showed that based on the experiment,knowledge had a significant effect with a correlation coefficient of 0.94,attitudes had an effect of 0.91,motivation was 0.756,and behavior was 0.865.It can be concluded that the construction of family toilets in the coastal areas of Pangkep and Maros Regencies,before the experiment,the knowledge,attitudes,motivation,and behavior of the community were in the low category,and after the experiment increased significantly to the high category. In addition, the results of the analysis showed that the experiment had a significant effect on increasing theknowledge, attitudes, motivation, and behavior of the community towards the construction of family toilets in coastal areas. 展开更多
关键词 Family Toilets KNOWLEDGE ATTITUDE MOTIVATION Coastal area
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Investigation and Analysis of Farmers'Livelihood Capitals in Ecological Development Area of Northern Guangdong Province:A Case Study of Yangshan County
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作者 Jinguo HUANG Xi HUANG +1 位作者 Chengchao WANG Xizhi WANG 《Asian Agricultural Research》 2025年第8期9-12,共4页
Investigation and analysis of the current status of farmers'livelihood capital and promptly discovering and solving problems in farmers'livelihood development are of great practical significance for optimizing... Investigation and analysis of the current status of farmers'livelihood capital and promptly discovering and solving problems in farmers'livelihood development are of great practical significance for optimizing farmers'livelihood strategies and enhancing farmers'livelihood sustainable development capability.Based on the framework of sustainable livelihood analysis,taking Yangshan County as an example,this paper uses field surveys,questionnaires and interviews to summarize and analyze the current status and characteristics and main problems of local farmers'livelihood capitals on the basis of the data of 628 farmer samples.It proposes countermeasures for future development of farmers'livelihoods.Implementing these strategies will be helpful for improving the livelihoods capital structure of farmers'and enhancing their sustainable development capability. 展开更多
关键词 LIVELIHOOD capitals Investigation and analysis Future DEVELOPMENT strategy Ecological DEVELOPMENT area of NORTHERN GUANGDONG Province
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Prevalence and Potential Risk Predictors of Undernutrition Among Under-Five Children in Island Areas of Bangladesh
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作者 Md.Abdul Aziz Mohammad Mozibul Haque +3 位作者 Afia Nawar Kazi Nazira Sharmin Md.Altaf Hossain Suvanker Saha 《Health Care Science》 2025年第6期381-391,共11页
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
关键词 child health island area risk factor under-five-children UNDERNUTRITION
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Alkaline igneous rocks,a potential source of rare metals and radioactive minerals:Case study at Amreit area,south Eastern Desert,Egypt
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作者 Baaha M.Emad 《Acta Geochimica》 2025年第1期189-214,共26页
Alkaline igneous rocks represent one of the most economically important resources of radioactive minerals and rare metals.New field observations and petrographic studies are integrated with whole-rock geochemical anal... Alkaline igneous rocks represent one of the most economically important resources of radioactive minerals and rare metals.New field observations and petrographic studies are integrated with whole-rock geochemical analyses and Gamma ray spectroscopy data of alkaline rocks associated with the Amreit complex.The fieldwork was achieved by the collection of more than forty samples from alkaline granites and alkaline syenites.The youngest rocks cropping out in the study area are the cogenetic alkaline rocks,ranging from alkaline granite to alkaline syenite.These alkaline rocks are composed essentially of K-feldspar,alkali amphiboles(arfvedsonite),and sodic pyroxene,with accessories such as zircon,apatite,and ilmenite.Mineral characterization of the highly radioactive zones in both alkaline granite and alkaline syenite displays enrichment in monazite,thorite,zircon,ferro-columbite,xenotime,and allanite minerals.Geochemical analyses indicate that the Amreit rocks are alkaline with peralkaline affinity and have high concentrations of total alkalis(K_(2)O+Na_(2)O),large ion lithophile elements(LILEs;Ba and Rb),high field strength elements(HFSEs;Y,Zr and Nb),rare earth elements(REEs)and significantly depleted in K,Sr,P,Ti,and Eu,typically of post-collision A-type granites.Typically,the Amreit alkaline igneous rocks are classified as within plate granites and display A2 subtype characteristics.The fractionation of K-feldspars played a distinctive role during the magmatic evolution of these alkaline rocks.The geochemical characteristics indicate that the studied alkaline igneous rocks which were originated by fractional crystallization of alkaline magmas were responsible for the enrichment of the REE and rare metals in the residual melt.The high radioactivity is essentially related to accessory minerals,such as zircon,allanite,and monazite.The alkaline granite is the most U-and Thrich rock,where radioactivity level reaches up to 14.7 ppm(181.55 Bq/kg)e U,40.6 ppm(164.84 Bq/kg)e Th,whereas in alkaline syenite radioactivity level is 8.5 ppm(104.96 Bq/kg)e U,30.2 ppm(122.61 Bq/kg)e Th.These observations suppose that these alkaline rocks may be important targets for REEs and radioactive mineral exploration. 展开更多
关键词 Amreit area Alkaline rocks RADIOACTIVITY Geochemistry Post-collision A-type granite EGYPT
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Gap dynamics in the U.S.between urban areas in the current trend and in sustainable scenario
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作者 Haoyu Wang Xiuyuan Zhang +6 位作者 Shihong Du Yuyu Zhou Donghai Wu Qian Wang Lubin Bai Bo Liu Shuping Xiong 《Geography and Sustainability》 2025年第1期143-158,共16页
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
关键词 Urban areas in the current trend Urban areas in the sustainable scenario Urban gap dynamics Urban sustainability
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Quantitative analysis of pore evolution and its application in basin simulation:A case study of Chang 6 reservoir in Heshui area,Ordos Basin,NW China
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作者 Ting Shang Meijuan Chu +5 位作者 Xiaolei Zhang Bin Wang Jihong Li Huiruo Zhang Zhongyi Zhang Xin Liu 《Energy Geoscience》 2025年第2期423-435,共13页
In recent years,fueled by significant advancements in oil exploration technologies within the Ordos Basin,an increasing number of low-permeability or ultra-low-permeability reservoirs have been identified.Elucidating ... In recent years,fueled by significant advancements in oil exploration technologies within the Ordos Basin,an increasing number of low-permeability or ultra-low-permeability reservoirs have been identified.Elucidating their reservoir characteristics and formation mechanisms has become a critical priority for sustainable hydrocarbon development.The study focused on the Chang 6 Member of the Upper Triassic Yanchang Formation in the Heshui area of the Ordos Basin,systematically investigating its petrological features,porosity and permeability characteristics,diagenesis,and diagenetic evolution sequence.By integrating core observation,thin-section identification,and physical property measurements,a comprehensive quantitative evaluation of reservoir pore evolution was performed.These analytical outcomes were subsequently applied to simulate hydrocarbon migration and accumulation.These research results will provide a scientific basis for in-depth quantitative study of the pore evolution in ultra-low-permeability oil reservoirs and accurately constructing basin models.As indicated,the reservoir lithology in the study area predominantly comprises siltstone interbedded with mudstone or argillaceous siltstone,characterized by low porosity and permeability.Through diagenetic characteristics-based reconstruction constrained by the existing porosity data,pore evolution during diagenesis was quantitatively modeled.The simulated pore evolution aligns with actual geological observations,validating the reliability of the methodology.Furthermore,the quantified pore evolution results were applied to simulate hydrocarbon migration using PetroMod software,showing that hydrocarbon charging in the basin began at the end of the Late Jurassic(J3),peaking in hydrocarbon generation,expulsion,and accumulation by the end of the Early Cretaceous(K1)and maintaining high accumulation rates until the late Cretaceous,though significantly decreasing at the present stage.The simulation results were verified by comparison with actual drilling data,which confirms their reliability and applicability to other analogous oilfields. 展开更多
关键词 Ordos Basin Heshui area DIAGENESIS Pore evolution Basin modeling
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Evaluating the climate change robustness of Canadian protected area management plans
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作者 Stephanie Barr Christopher J.Lemieux +2 位作者 Jen Hoesen Brooklyn Rushton Pamela Wright 《Geography and Sustainability》 2025年第3期17-29,共13页
Climate change is increasingly affecting all aspects of protected areas management from changes of species ranges to visitor experiences.Due to these impacts,there is a need for managers to take more robust approaches... Climate change is increasingly affecting all aspects of protected areas management from changes of species ranges to visitor experiences.Due to these impacts,there is a need for managers to take more robust approaches to con-sidering the implications of climate change on the overall application and efficacy of protected areas management direction,including the achievement of the goals and objectives contained within management plans.Through a systematic and comprehensive content analysis approach,this study assesses the current extent to which climate change is considered in Canadian protected area management plans.Specifically,we evaluated 63 terrestrial protected area management plans against a set of climate robustness principles.Our content analysis revealed that climate change is currently not effectively factored into Canadian protected area management plans with an average climate robustness score of 18%.Climate robustness score was not found to be correlated with protected area size,International Union for the Conservation of Nature(IUCN)management classification,or jurisdictional authority.Certain climate robustness principles received higher scores across the management plans than oth-ers.For example,the principles of‘diverse knowledge sources’and‘addresses climate change’scored relatively highly whereas‘climate change vulnerability’and‘ecosystem integrity’received the lowest scores.The lack of integration of ecological integrity considerations in management plans was a particularly noteworthy deficiency considering that this guiding principle is the primary legislative objective of many national and sub-national protected areas in Canada.From this assessment,climate change needs to be more effectively and consistently integrated into protected area management plan development and coordinated across associated planning pro-cesses.We discuss the ways in which this can be achieved,for example,by integrating scenario planning into organizational management plan development processes. 展开更多
关键词 Climate change Protected areas Management plans PLANNING Effectiveness Evaluation
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Preparation of Mo2CTx MXene with high specific surface area by etching of acetic acid/acetate solution
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作者 ZHANG Guang-lei DU Ya-qiong +4 位作者 GUO Yi-tong LIU Han WANG Li-bo JIANG Ji-zhou ZHOU Ai-guo 《Journal of Central South University》 2025年第10期3807-3819,共13页
Mo_(2)CT_(x)MXene is a novel two-dimensional material,which is generally made by the etching of inorganic acid solutions,such as hydrofluoric acid(HF)or hydrochloric acid(HCl).Those solutions are always corrosive and ... Mo_(2)CT_(x)MXene is a novel two-dimensional material,which is generally made by the etching of inorganic acid solutions,such as hydrofluoric acid(HF)or hydrochloric acid(HCl).Those solutions are always corrosive and hazardous.In this paper,a mild organic acid,acetic acid(CH_(3)COOH),was selected to synthesize Mo_(2)CT_(x)MXene.30 mL acetic acid(HAc)with the concentration of 13 mol/L was mixed with 2 g acetate(CH_(3)COONa or CH_(3)COOK)and 10 mL water to make etching solution(NaAc+HAc or KAc+HAc).In the solution,the concentration of CH_(3)COO^(-)was 10 mol/L,the concentration of Na^(+)/K^(+)is 0.6/0.5 mol/L.The pH value is 2.8.Mo_(2)CT_(x)was obtained by hydrothermal etching at 240℃for 1 d.Compared with the general method of HF etching,the etchant is milder and the etching process is safer.On the surface of Mo_(2)CT_(x)nanosheet made by this method,acetate group(CH_(3)COO^(-))was adsorbed as termination,which is larger than the F/O/OH termination of that made by general HF etching.The lattice parameter c(LP c)of Mo_(2)CT_(x)etched with NaAc+HAc/KAc+HAc is 21.09Å/20.89Å.Moreover,the specific surface areas of the samples etched by NaAc+HAc and KAc+HAc were 18.1 m^(2)/g and 14.1 m^(2)/g,respectively,which were much larger than those etched by conventional methods.As the anode of lithium-ion battery,the specific capacity under current density of 100 mA/g at 100 th cycle was 108 mA·h/g,which is higher than the capacity of samples made by general HF etching.This work reports a novel method to make Mo_(2)CT_(x)MXene by the solution of mild acetic acid.The samples made by this method had very high specific surface area and relatively high lithium-storage performance. 展开更多
关键词 MXene acetic acid specific surface area lithium-ion-batteries
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Paleo-fluid evolution in the Lower-Middle Ordovician carbonate reservoirs of the Shunbei area,Tarim Basin
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作者 Bai-Wen Huang Ning Ye +7 位作者 Zi-Ye Lu Bei Zhu Yi-Ming Yang Pan Lin Pei-Jie Li Xin-Yan Zhang Ying-Tao Li Shao-Nan Zhang 《Petroleum Science》 2025年第6期2290-2306,共17页
Deep carbonate reservoirs affected by prominent strike-slip faults represent crucial targets in oil and gas exploration owing to their immense resource potential.However,the complex geological environments and poorly ... Deep carbonate reservoirs affected by prominent strike-slip faults represent crucial targets in oil and gas exploration owing to their immense resource potential.However,the complex geological environments and poorly understood histories of the associated paleo-fluid activity have hindered the development of robust theories regarding pore formation and preservation mechanisms,resulting in suboptimal exploration strategies.Leveraging the extensive well deployment by the China Sinopec Group in the Shunbei area of the Tarim Basin,this study addresses these challenges by establishing a comprehensive framework for the evolution of diagenetic fluids within the Middle-Lower Ordovician carbonate formations.Using core samples,thin-section analysis,and cathodoluminescence observations,this study employs high-resolution geochemical methodologies,including isotopic analyses,rare earth element profiling,fluid inclusion studies,and uranium-lead dating,as primary tools for identifying and interpreting paleo-fluid characteristics across various rock types and calcite cement varieties within this stratigraphic interval.The findings reveal several key insights:(i)both RFC and C1 cements are derived from seawater,with C1 forming under burial conditions;(ii)C2,C3,and VC cements result from distinct tectonic events,specifically during the first and third episodes of the Middle Caledonian movement,with meteoric water infiltrating fault systems independently of orogenic belts or paleo-karst systems;and(iii)previous conclusions are challenged,as the influence of hydrothermal activity in this area is found to be minimal.Furthermore,the model presented here serves as a valuable reference for understanding fluid activity events at distal locations within orogenic belts under compressive stress,while accurately capturing fluid variations over different temporal scales within fault zones plays a decisive role. 展开更多
关键词 Calcite cements GEOCHEMISTRY Paleo-fluid flows Shunbei area Tarim basin
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