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Contrastive mechanisms of lacustrine groundwater discharge and associated pollutant fluxes into two typical inland lakes in Inner Mongoli1,Northwest China
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作者 Yuanzhen Zhao Xiaohui Ren +5 位作者 Shen Qu Fu Liao Keyi Zhang Muhan Li Juliang Wang Ruihong Yu 《Journal of Environmental Sciences》 2026年第1期661-669,共9页
Lacustrine groundwater discharge(LGD)plays an important role in water resources management.Previous studies have focused on LGD process in a single lake,but the differences in LGD process within the same region have n... Lacustrine groundwater discharge(LGD)plays an important role in water resources management.Previous studies have focused on LGD process in a single lake,but the differences in LGD process within the same region have not been thoroughly investigated.In this study,multiple tracers(hydrochemistry,𝛿D,𝛿18O and 222Rn)were used to compare mechanisms of LGD in Daihai and Ulansuhai Lake in Inner Mongoli1,Northwest China.The hydrochemical types showed a trend from groundwater to lake water,indicating a hydraulic connection between them.In addition,the𝛿D and𝛿18O values of sediment pore water were between the groundwater and lake water,indicating the LGD processes.The radon mass balance model was used to estimate the average groundwater discharge rates of Daihai and Ulansuhai Lake,which were 2.79 mm/day and 3.02 mm/day,respectively.The total nitrogen(TN),total phosphorus(TP),and fluoride inputs associated with LGD in Daihai Lake accounted for 97.52%,96.59%,and 95.84%of the total inputs,respectively.In contrast,TN,TP and fluoride inputs in Ulansuhai Lake were 53.56%,40.98%,and 36.25%,respectively.This indicates that the pollutant inputs associated with LGD posed a potential threat to the ecological stability of Daihai and Ulansuhai Lake.By comparison,the differences of LGD process and associated pollutant flux were controlled by hydrogeological conditions,lakebed permeability and human activities.This study provides a reference for water resources management in Daihai and Ulansuhai Lake basins while improving the understanding of LGD in the Yellow River basin. 展开更多
关键词 Lacustrine groundwater discharge 222Rn mass balance model Pollutant fluxes Contrastive mechanisms Daihai and Ulansuhai Lake
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Spatial pattern and conservation challenges of migratory waterbirds in Asian flyways
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作者 Wenzhang Dai Jun Chen +3 位作者 Shanshan Zhao Luning Lian Xin Leng Xiaodan Wang 《Avian Research》 2026年第1期59-66,共8页
Migratory birds undertake regular seasonal movements between breeding and non-breeding grounds each year,often spanning intercontinental distances.Several migratory waterbirds are declining globally,owing to multiple ... Migratory birds undertake regular seasonal movements between breeding and non-breeding grounds each year,often spanning intercontinental distances.Several migratory waterbirds are declining globally,owing to multiple threats from parts of annual migration.Therefore,understanding the spatial distribution and conservation challenges of migratory waterbirds is critical for effective flyway-scale conservation.In this study,we compiled a comprehensive dataset of 199 migratory waterbird species,mapped seasonal distribution,and identified population trends and threats along the East Asian-Australasian Flyway and Central Asian Flyway.Species richness exhibited latitudinal gradients along the two flyways,peaking at approximately 60°N in the breeding season and15°N in the non-breeding season.Migration distance and geographic spread significantly varied among orders.More than half of the waterbird species(50.75%)showed decreasing population trends;however,no significant difference in the proportion of population decline was noticed across flyways or orders.A total of 31 species(15.58%)were listed as threatened,most of which were concentrated in the East Asian-Australasian Flyway and primarily affected by the use of biological resources,pollution,and agricultural expansion.Overall,this study provides a comparative assessment of migratory waterbirds in Asian flyways.Our findings highlight the importance of multinational conservation efforts targeting key breeding and non-breeding regions,specifically for threatened species,and underscore the need for coordinated strategies to mitigate multiple,overlapping threats across flyways.These further emphasize that conservation actions should prioritize transboundary habitat networks and policy integration among flyway countries to enhance the long-term resilience of migratory waterbird populations. 展开更多
关键词 Asian flyway Migratory waterbird Population trend Threatened species
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Corrigendum to“Exploring the HONO source during the COVID-19 pandemic in a megacity in China”[Journal of Environmental Sciences Volume 149(2025)616-627]
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作者 Mingkai Wang Shenbo Wang +6 位作者 Ruiqin Zhang Minghao Yuan Yifei Xu Luqi Shang Xinshuai Song Xinyuan Zhang Yunxiang Zhang 《Journal of Environmental Sciences》 2025年第10期894-894,共1页
The authors regret that in 1.2.Instruments section of the article,when describing the principle of TiH300,the original content of“Briefly,ambient HONO was first absorbed by deionized water in a two-channel stripping ... The authors regret that in 1.2.Instruments section of the article,when describing the principle of TiH300,the original content of“Briefly,ambient HONO was first absorbed by deionized water in a two-channel stripping coil.The absorbed liquid nitrite was mixed with sulfanilamide,N-(1-naphthyl)-ethylenediamine dihydrochloride,and hydrogen chloride solution to form the azo dye derivative.” 展开更多
关键词 MEGACITY hydrogen chloride azo dye derivative deionized water HONO China liquid nitrite SOURCE
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Establishment and verification of anthropogenic speciated VOCs emission inventory of Central China 被引量:3
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作者 Xuan Lu Dong Zhang +9 位作者 Lanxin Wang Shefang Wang Xinran Zhang Yali Liu Keying Chen Xinshuai Song Shasha Yin Ruiqin Zhang Shanshan Wang Minghao Yuan 《Journal of Environmental Sciences》 2025年第3期406-418,共13页
Improving the accuracy of anthropogenic volatile organic compounds(VOCs)emission inventory is crucial for reducing atmospheric pollution and formulating control policy of air pollution.In this study,an anthropogenic s... Improving the accuracy of anthropogenic volatile organic compounds(VOCs)emission inventory is crucial for reducing atmospheric pollution and formulating control policy of air pollution.In this study,an anthropogenic speciated VOCs emission inventory was established for Central China represented by Henan Province at a 3 km×3 km spatial resolution based on the emission factormethod.The 2019 VOCs emission in Henan Provincewas 1003.5 Gg,while industrial process source(33.7%)was the highest emission source,Zhengzhou(17.9%)was the city with highest emission and April and August were the months with the more emissions.High VOCs emission regions were concentrated in downtown areas and industrial parks.Alkanes and aromatic hydrocarbons were the main VOCs contribution groups.The species composition,source contribution and spatial distribution were verified and evaluated through tracer ratio method(TR),Positive Matrix Factorization Model(PMF)and remote sensing inversion(RSI).Results show that both the emission results by emission inventory(EI)(15.7 Gg)and by TRmethod(13.6 Gg)and source contribution by EI and PMF are familiar.The spatial distribution of HCHO primary emission based on RSI is basically consistent with that of HCHO emission based on EI with a R-value of 0.73.The verification results show that the VOCs emission inventory and speciated emission inventory established in this study are relatively reliable. 展开更多
关键词 VOCs verification Species composition Tracer ratio PMF Remote sensing inversion
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Community phylogenetic structure of grasslands and its relationship with environmental factors on the Mongolian Plateau 被引量:4
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作者 DONG Lei LIANG Cunzhu +8 位作者 LI Frank Yonghong ZHAO Liqing MA Wenhong WANG Lixin WEN Lu ZHENG Ying LI Zijing ZHAO Chenguang Indree TUVSHINTOGTOKH 《Journal of Arid Land》 SCIE CSCD 2019年第4期595-607,共13页
The community assembly rules and species coexistence have always been interested by ecologists. The community phylogenetic structure is the consequence of the interaction process between the organisms and the abiotic ... The community assembly rules and species coexistence have always been interested by ecologists. The community phylogenetic structure is the consequence of the interaction process between the organisms and the abiotic environment and has been used to explain the relative impact of abiotic and biotic factors on species co-existence. In recent years, grassland degradation and biodiversity loss have become increasingly severe on the Mongolian Plateau, while the drivers for these changes are not clearly explored, especially whether climate change is a main factor is debated in academia. In this study, we examined the phylogenetic structure of grassland communities along five transects of climate aridity on the Mongolian Plateau, and analyzed their relations with environmental factors, with the aims to understand the formation mechanism of the grassland communities and the role of climatic factors. We surveyed grassland communities at 81 sites along the five transects, and calculated their net relatedness index(NRI) at two different quadrat scales(small scale of 1 m2 and large scale of 5 m2) to characterize the community phylogenetic structure and analyze its relationship with the key 11 environmental factors. We also calculated the generalized UniFrac distance(GUniFrac) among the grassland communities to quantify the influence of spatial distance and environmental distance on the phylogenetic β diversity. The results indicated that plant community survey using the large scale quadrat contained sufficient species to represent community compositions. The community phylogenetic structure of grasslands was significantly overdispersed at both the small and large scales, and the degree of overdispersion was greater at the large scale than at the small scale, suggesting that competitive exclusion instead of habitat filtering played a major role in determination of community composition. Altitude was the main factor affecting the community phylogenetic structure, whereas climatic factors, such as precipitation and temperature, had limited influence. The principal component analysis of the 11 environmental factors revealed that 94.04% of their variation was accounted by the first four principal components. Moreover only 14.29% and 23.26% of the variation in community phylogenetic structure were explained by the first four principal components at the small and large scales, respectively. Phylogenetic β diversity was slightly significantly correlated with both spatial distance and environmental distance, however, environmental distance had a less explanatory power than spatial distance, indicating a limited environmental effect on the community phylogenetic structure of grasslands on the Mongolian Plateau. In view of the limited effect of climatic factors on the community phylogenetic structure of grasslands, climate change may have a smaller impact on grassland degradation than previously thought. 展开更多
关键词 PHYLOGENETIC overdispersion ENVIRONMENTAL factors PHYLOGENETIC β diversity spatial scale ENVIRONMENTAL distance CLIMATE change MONGOLIAN PLATEAU
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Spatial and historical distribution of organic phosphorus driven by environment conditions in lake sediments 被引量:3
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作者 Changwei Lü Jiang He Bing Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第2期32-41,共10页
The chemistry of sedimentary organic phosphorus(OP) and its fraction distribution in sediments are greatly influenced by environmental conditions such as terrestrial inputs and runoffs. The linkage of OP with enviro... The chemistry of sedimentary organic phosphorus(OP) and its fraction distribution in sediments are greatly influenced by environmental conditions such as terrestrial inputs and runoffs. The linkage of OP with environmental conditions was analyzed on the basis of OP spatial and historical distributions in lake sediments. The redundancy analysis and OP spatial distribution results suggested that both Na OH-OP(OP extracted by Na OH) and Re-OP(residual OP) in surface sediments from the selected 13 lakes reflected the gradient effects of environmental conditions and the autochthonous and/or allochthonous inputs driven by latitude zonality in China. The lake level and salinity of Lake Hulun and the runoff and precipitation of its drainage basin were reconstructed on the basis of the geochemistry index. This work showed that a gradient in weather conditions presented by the latitude zonality in China impacts the OP accumulation through multiple drivers and in many ways.The drivers are mainly precipitation and temperature, governing organic matter(OM)production, degradation rate and transportation in the watershed. Over a long temporal dimension(4000 years), the vertical distributions of Re-OP and Na OH-OP based on a dated sediment profile from HLH were largely regulated by the autochthonous and/or allochthonous inputs, which depended on the environmental and climate conditions and anthropogenic activities in the drainage basin. This work provides useful environmental geochemistry information to understand the inherent linkage of OP fractionation with environmental conditions and lake evolution. 展开更多
关键词 Organic phosphorus Spatial and historical distribution Environmental conditions SEDIMENT LAKE
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Leaf habit and plant height are associated with mortality risk of trees and shrubs during extreme drought in a Chinese savanna ecosystem 被引量:1
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作者 Fangyu Dai Yanru Hou +4 位作者 Zhongfei Li Handong Wen Tianliang Li Yajun Chen Shubin Zhang 《Journal of Forestry Research》 2025年第5期202-214,共13页
Climate change has significantly increased the frequency and severity of droughts and risk of tree death worldwide.Differences in leaf habit,plant size,and species diversity are associated with differences in the risk... Climate change has significantly increased the frequency and severity of droughts and risk of tree death worldwide.Differences in leaf habit,plant size,and species diversity are associated with differences in the risk of drought-induced mortality,but the relative contributions of these factors to the risk of mortality are unclear.In a study of the mortality of tree and shrub species during the extreme drought of 2019 in a savanna ecosystem in Southwest China,we assessed the relative contributions of evergreen and deciduous leaf habit,plant size,and species richness and diversity to the mortality of shrubs and trees after the 2019 extreme drought.The deciduous species had significantly lower hydraulic safety margins than the coexisting evergreen species,resulting in a higher mortality risk.Additionally,species and individuals with taller canopies tended to have deeper root systems,an advantage during extreme drought that reduced mortality risk.Notably,mortality risk was largely independent of stand species richness and diversity.Overall,leaf habit and plant height were better predictors of mortality risk than species richness and diversity.These novel insights provide a better understanding of the mechanisms driving drought-induced mortality in the ecosystems with a low canopy and weak interspecific and intraspecific competition for shared resources.Leaf habit and tree size should be incorporated into hypotheses on the mechanisms underlying drought-induced tree mortality. 展开更多
关键词 Drought-induced mortality Hydraulic safety margin Root depth SAVANNA Species diversity
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Species’ geographical range, environmental range and traits lead to specimen collection preference of dominant plant species of grasslands in Northern China 被引量:1
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作者 Jingya Zhang Cui Xiao +5 位作者 Xiaoyu Duan Xin Gao Hao Zeng Rong'an Dong Gang Feng Keping Ma 《Plant Diversity》 SCIE CAS CSCD 2024年第3期353-361,共9页
Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection preference.This study aims to determine whether grassland specimen collection... Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection preference.This study aims to determine whether grassland specimen collection in China is preferred by species traits(i.e.,plant height,flowering and fruiting period),environmental range(i.e.,the temperature and precipitation range)and geographical range(i.e.,distribution range and altitudinal range).Ordinary least squares models and phylogenetic generalized linear mixed models were used to analyze the relationships between specimen number and the explanatory variables.Random Forest models were then used to find the most parsimonious multivariate model.The results showed that interannual variation in specimen number between 1900 and 2020 was considerable.Specimen number of these species in southeast China was notably lower than that in northwest China.Environmental range and geographical range of species had significant positive correlations with specimen number.In addition,there were relatively weak but significant associations between specimen number and species trait(i.e.,plant height and flowering and fruiting period).Random Forest models indicated that distribution range was the most important variable,followed by flowering and fruiting period,and altitudinal range.These findings suggest that future floristic surveys should pay more attention to species with small geographical range,narrow environmental range,short plant height,and short flowering and fruiting period.The correction of specimen collection preference will also make the results of species distribution model,species evolution and other works based on specimen data more accurate. 展开更多
关键词 Biological specimen Collection preference Dominant plant species Environmental range Geographical range Species traits
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Extracting critical paths for synergistic control of carbon emissions and air pollution:Case of Henan Province
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作者 Ningwei Wang Shanshan Wang +3 位作者 Yeke Li Yingying Zhao Tiantian Chun Ruiqin Zhang 《Journal of Environmental Sciences》 2025年第9期235-249,共15页
Synergistic reduction of carbon emissions and air pollution is the core means to address the two major strategic tasks of fundamentally improving the ecological environment and the‘Dual-carbon target’.The issue of s... Synergistic reduction of carbon emissions and air pollution is the core means to address the two major strategic tasks of fundamentally improving the ecological environment and the‘Dual-carbon target’.The issue of synergistic reduction at the provincial level needs to be addressed as a matter of urgency.Taking Henan Province,the largest economy in central China,as an example,this study uses environmentally extended input-output analysis and structural path analysis to identify the key sectors that contribute to CO_(2),SO_(2),and total particulate matter(TPM)emissions,and to sort out key emission pathways(e.g.,Final Demand→Sector…).The results indicate that S2(Mining of Fossil Energy),S10(Nonmetal Mineral Products),S11(Metal Smelting),S13(Power and Heat)and S17(Transportation)are mainly responsible for CO_(2),SO_(2),and TPM direct emissions on the production side,while S16(Construction),S12(Equipment)and S18(Services)account for more than 45%of CO_(2),SO_(2),and TPM embodied emissions on the consumption side.32 shared emission pathways are extracted from the top 100 pathways for CO_(2),SO_(2),and TPM emissions,which account for 27%-51%of total emissions in Henan Province.P9(Export→Nonmetal Mineral Products),P10(Export→Metal Smelting)and P21(Gross Capital Formation→Construction→Nonmetal Mineral Products)are the leading paths responsible for embodied emissions.The research results provide the foundation and guidance for well-designed mitigation policies,as well as a reference for better synergistic control in provinces facing similar situations. 展开更多
关键词 Synergistic control Environmentally extended input-output analysis Structural path analysis Supply chains Embodied emissions
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Treatment of dehydration wastewater from licorice residue via a novel microaerobic-aerobic combined process:Performance and microbial community
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作者 Yongqi Liang Chuchu Chen +4 位作者 Yihong Chen Huazhe Wang Qi Zhao Qinglian Wu Wan-Qian Guo 《Chinese Chemical Letters》 2025年第10期499-505,共7页
The initial step in the resource utilization of Chinese medicine residues(CMRs)involves dehydration pretreatment,which results in high concentrations of organic wastewater and leads to environmental pollution.Meanwhil... The initial step in the resource utilization of Chinese medicine residues(CMRs)involves dehydration pretreatment,which results in high concentrations of organic wastewater and leads to environmental pollution.Meanwhile,to address the issue of anaerobic systems failing due to acidification under shock loading,a microaerobic expanded granular sludge bed(EGSB)and moving bed sequencing batch reactor(MBSBR)combined process was proposed in this study.Microaeration facilitated hydrolysis,improved the removal of nitrogen and phosphorus pollutants,maintained a low concentration of volatile fatty acids(VFAs),and enhanced system stability.In addition,microaeration promoted microbial richness and diversity,enriching three phyla:Bacteroidota,Synergistota and Firmicutes associated with hydrolytic acidification.Furthermore,aeration intensity in MBSBR was optimized.Elevated levels of dissolved oxygen(DO)impacted biofilm structure,suppressed denitrifying bacteria activity,led to nitrate accumulation,and hindered simultaneous nitrification and denitrification(SND).Maintaining a DO concentration of 2 mg/L enhanced the removal of nitrogen and phosphorus while conserving energy.The combined process achieved removal efficiencies of 98.25%,90.49%,and 98.55%for chemical oxygen demand(COD),total nitrogen(TN),and total phosphorus(TP),respectively.Typical pollutants liquiritin(LQ)and glycyrrhizic acid(GA)were completely degraded.This study presents an innovative approach for the treatment of high-concentration organic wastewater and provides a reliable solution for the pollution control in utilization of CMRs resources. 展开更多
关键词 Combined process Pollutants removal Microaeration Expanded granular sludge bed Moving bed sequencing batch reactor Waste management
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Establish of air pollutants and greenhouse gases emission inventory and co-benefits of their reduction of transportation sector in Central China
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作者 Xinran Zhang Shasha Yin +7 位作者 Xuan Lu Yali Liu Tiantian Wang Binglin Zhang Zhuo Li Wenju Wang Mengdi Kong Keying Chen 《Journal of Environmental Sciences》 2025年第4期604-621,共18页
Recently,the transportation sector in China has gradually become the main source of urban air pollution and primary driver of carbon emissions growth.Considering air pollutants and greenhouse gases come from the same ... Recently,the transportation sector in China has gradually become the main source of urban air pollution and primary driver of carbon emissions growth.Considering air pollutants and greenhouse gases come from the same emission sources,it is necessary to establish an updated high-resolution emission inventory for the transportation sector in Central China,themost polluted region in China.The inventory includes on-road mobile,non-roadmobile,oil storage and transportation,and covers 9 types of air pollutants and 3 types of greenhouse gases.Based on the Long-range Energy Alternatives Planning System(LEAP)model,the emissions of pollutants were predicted for the period from2020 to 2035 in different scenarios.Results showed that in 2020,emissions of SO_(2),NO_(x),CO,PM_(10),PM_(2.5),VOCs,NH_(3),BC,OC,CO_(2),CH_(4),and N_(2)O in Henan Province were 27.5,503.2,878.6,20.1,17.4,222.1,21.5,9.4,2.9,92,077.9,6.0,and 10.4 kilotons,respectively.Energy demand and pollutant emissions in Henan Province are simulated under four scenarios(Baseline Scenario(BS),Pollution Abatement Scenario(PA),Green Transportation Scenario(GT),and Reinforcing Low Carbon Scenario(RLC)).The collaborative emission reduction effect is most significant in the RLC scenario,followed by the GT scenario.By 2035,under the RLC scenario,energy consumption and emissions of SO_(2),NO_(x),CO,PM_(10),PM_(2.5),VOCs,NH_(3),CO_(2),CH_(4),and N_(2)O are projected to decrease by 72.0%,30.0%,55.6%,56.0%,38.6%,39.7%,51.5%,66.1%,65.5%,55.4%,and 52.8%,respectively.This study provides fundamental data support for subsequent numerical simulations. 展开更多
关键词 Emission inventory Transport sector LEAP model Co-benefit emission reduction Scenario analysis
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Proactive adaptation to climate change in landscape configuration and agricultural management optimization:A case study of agro-pastoral transitional zone in northern China
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作者 Jianmin Qiao Yuhang Gao +4 位作者 Ziyan Lv Zidong Tang Shike Xie Qian Cao Xiao Sun 《Geography and Sustainability》 2025年第6期239-252,共14页
Optimizing landscape patterns and management measures would be an effective strategy for the agro-pastoral transitional zone in northern China(ATNC)to adapt to future climate change.Existing studies generally focus on... Optimizing landscape patterns and management measures would be an effective strategy for the agro-pastoral transitional zone in northern China(ATNC)to adapt to future climate change.Existing studies generally focus on cropland or pasture,and thus there is a lack of comprehensive understanding of the landscape composition and configuration in complex agro-pastoral transitional zone.In this study,Ansai County in the ATNC was chosen as an experimental area.Four typical agroecosystem services(AESs),food provision(FP),soil carbon(SC),soil retention(SR)and water yield(WY)from 1980 to 2020,were simulated by spatially integrating a model of the agricultural system using the Environmental Policy Integrated Climate(EPIC)combined with geographic information systems technology.The impacts of different crop types,pasture configurations,and tillage practices on AESs under future climate scenarios were assessed in the context of agro-pastoral transition.Finally,the optimal landscape pattern configuration and management measures were identified through single-objective and multi-objective optimization models.The results showed that under historical scenarios,implementing policies such as converting cropland to pastureland improved SC and SR but reduced FP and WY.Compared to traditional and reduced tillage,no-till practices benefited the enlargement of AESs and the agricultural ecosystem.Notably,future climate change generally negatively affected AESs,especially under the Shared Socioeconomic Pathway(SSP5–8.5)climate scenario.The combination of planting corn and no-till measures would be ideal for optimizing the agricultural ecosystem in Ansai County.For the fragile ATNC,we should advocate conservation agriculture and policies converting cropland to pastureland to mitigate the adverse impacts of climate changes.This study establishes a replicable framework to address landscape management in complex agropastoral systems and offers solutions for climate-resilient land management in global dryland transitional zones,contributing to the realization of regional ecosystem sustainability. 展开更多
关键词 GEO_EPIC model Agroecosystem services Scenario simulation Landscape optimization Agro-pastoral transitional zone
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Equilibrium Characteristics and Obstacle Factors of the Life Service Level in the Yangtze River Delta,China
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作者 CHEN Zhiyu CAO Weidong +4 位作者 CAO Yuhong WANG Xuewei ZHANG Yizhen MA Jinji SHI Kaifang 《Chinese Geographical Science》 2025年第6期1411-1427,共17页
Under the new development pattern,promoting the balanced development of the regional life service level is the key to attaining the goal of meeting people’s need for an improved life.This study constructed an index s... Under the new development pattern,promoting the balanced development of the regional life service level is the key to attaining the goal of meeting people’s need for an improved life.This study constructed an index system with six dimensions,namely,economic base,innovation drive,living environment,transportation,public services and life security,and explored the balanced characteristics and obstacles of the life service level in the Yangtze River Delta,China in 2020 using the Gini coefficient,the standard deviation ellipse,the global spatial autocorrelation,the equilibrium entropy and the obstacle degree model.Results show that:1)the current overall level of life services in the Yangtze River Delta is in relative equilibrium,and the Gini coefficient of three dimensions,namely,economic base,innovation drive and life security,is relatively low and on the verge of imbalance.2)The spatial pattern of the six dimensions of the overall level of the life service is oriented toward the‘southeast-northwest’direction with significant spatial differentiation and spatial agglomeration.3)At present,most of the cities have a comparative advantage in the coordination of their life services,and the potential of their life service system shows room for further improvement in the future.4)Currently,the quality of economic development,talent concentration,innovation inputs,innovation outputs,basic education,health care,cultural sharing,the living standards of the urban and rural residents and the construction of a transportation system are the main factors constraining the improvement of the level of life services in the Yangtze River Delta.This study attempts to research on the evaluation and measurement of regional life service level in the new era,and provides a reference for the promotion of regional coordination and sustainable development. 展开更多
关键词 life service level equilibrium characteristics obstacle factors Yangtze River Delta China
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Oxidation mechanism and performance control of manganese-based catalysts in soot oxidation
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作者 Tingyi Zhao Yuanjun Li +7 位作者 Chengchun Wu Wen Cao Jiahao Gong Menglan Xiao Zuguo Song Zhihui Shao Mingqin Zhao Bing Cui 《Green Energy & Environment》 2025年第7期1481-1502,共22页
The extensive use of diesel engines has led to significant emissions of pollutants,especially soot particles,which pose serious risks to both the environment and human health.At present,developing catalysts with low–... The extensive use of diesel engines has led to significant emissions of pollutants,especially soot particles,which pose serious risks to both the environment and human health.At present,developing catalysts with low–temperature activity,low cost,and high stability remains the core challenge in eliminating soot from diesel engine exhaust.This paper first reviews the mechanisms of soot catalytic oxidation.Based on these mechanisms,the current design directions for soot catalysts are summarized and discussed.On the one hand,the effects of modification methods such as doping,loading,and solid solution on the performance of manganese-based catalysts are reviewed from the perspective of intrinsic activity.On the other hand,the research progress on manganese-based catalysts with specific morphological structures for soot oxidation is explored.Following the identification of design strategies,the commonly used preparation methods to achieve these designs are also outlined.Finally,the paper highlights the challenges associated with manganese-based catalysts in soot catalysis and discusses future research and development directions. 展开更多
关键词 Soot oxidation Manganese-Based Catalysts Catalytic mechanism Intrinsic activity Morphology control
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Impact of broadleaf tree introduction on rhizosphere fungal communities and root phosphorus-cycling genes in conifers of near-natural transformed plantations
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作者 Zhanpeng Ye Chen Ning +4 位作者 Ting Liu Meirong Yan Wenyan Cai Jiyang Xiao Wende Yan 《Forest Ecosystems》 2025年第6期1236-1248,共13页
Phosphorus(P)is crucial for plant growth.However,its low availability in subtropical soils necessitates that trees rely on microorganisms for effective P acquisition.The introduction of broadleaf trees has been shown ... Phosphorus(P)is crucial for plant growth.However,its low availability in subtropical soils necessitates that trees rely on microorganisms for effective P acquisition.The introduction of broadleaf trees has been shown to facilitate P acquisition in coniferous plantations by altering the rhizosphere fungal communities.Despite this,functional shifts in these communities and the expression of root phosphorus cycling genes(PCGs)remain inadequately understood.This study investigated coniferous Pinus massoniana and Cunninghamia lanceolata plantations interplanted with broadleaf species associated with arbuscular mycorrhizal(AM)or ectomycorrhizal(ECM)fungi.Rhizosphere soil and fine roots from the conifers were analyzed to examine soil bioavailable P fractions,root mycorrhizal colonization,rhizosphere fungal community composition,enzyme function predictions,and root PCGs expression.We found that citric-P in rhizospheric soil of P.massoniana increased with the introduction of Quercus gilva(an ECM-associated tree species),whereas Bray-P content in the rhizosphere of C.lanceolata decreased upon the introduction of either Q.gilva or Phoebe zhennan(an ECM-associated tree species).Moreover,the relative abundance of saprophytic fungi(e.g.,Mortierella)increased following the introduction of broadleaf trees.Specifically,the introduction of Q.gilva was associated with elevated levels of organic P mineralization genes(e.g.,phoA)and enzymes(e.g.,phytases and acid phosphatase(ACP))in conifers.In contrast,the introduction of P.zhennan increased the expression of inorganic P solubilization genes(such as qppC in P.massoniana roots and ppa in C.lanceolata roots).Key contributors to P absorption in conifer roots included Cenococcum,Rhizopogon,and Glomus.This study advances our understanding of P cycling in coniferous rhizospheres and the dynamics of coexisting mycorrhizal tree systems,yielding valuable insights into sustainable management of plantation ecosystems. 展开更多
关键词 Near-natural transformed plantations Rhizosphere fungal community Phosphorus cycling genes Arbuscular mycorrhizal fungi Ectomycorrhizal fungi
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Runoff changes and influencing factors in the Nyang River Basin in Xizang
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作者 CAO Liang DONG Shi +2 位作者 WANG Yuyan LI Xingran CAO Pengxi 《Journal of Mountain Science》 2025年第10期3706-3720,共15页
This study aims to construct a large-scale hydrological Variable Infiltration Capacity(VIC)model based on temperature and precipitation at high altitudes,while elucidating the applicability of the model for hydrologic... This study aims to construct a large-scale hydrological Variable Infiltration Capacity(VIC)model based on temperature and precipitation at high altitudes,while elucidating the applicability of the model for hydrological simulation and analyzing the factors affecting runoff volume.Runoff volume and runoff depth were simulated using the VIC model and its performance was evaluated.Meanwhile,the factors affecting runoff volume were analyzed using Spearman correlation.The following model sensitivity parameters were obtained based on the China Natural Runoff Grid Point Dataset(CNRD v1.0):The variable infiltration curve parameter was 0.3,the Dsmax fraction where non-linear baseflow begins was 0.02,the maximum baseflow velocity was 15 mm/d,the maximum soil moisture where non-linear baseflow occurred was 0.7,the second soil moisture layer thickness was 0.3,and the thickness of the third soil moisture layer was 1.5.The surface runoff values in the Nyang River basin were similar in the first and fourth quarters(1.05–2.27 mm and 2.38–4.77 mm,respectively),and the surface runoff values were similar in the second and third quarters when the surface runoff was greater(23.46–52.20 mm and 60.59–85.63 mm,respectively).Watershed area,temperature,and precipitation significantly influenced the amount of runoff from the Nyang River.The applicability of the model to the Nyang River basin was confirmed using two different rate models.In some areas,precipitation and temperature did not have a dominating influence on runoff.Although the VIC model has significant advantages in runoff simulation,it requires a wealth of meteorological,soil,and hydrological data that may be difficult to obtain in some areas. 展开更多
关键词 Runoff changes Nyang river VIC model Meteorological changes Spearman correlation
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Synthesis of Ni/MnO/C nano-microspheres with synergistic effects of dielectric and magnetic loss for efficient microwave absorption
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作者 Chunwei Lei Jian Li +4 位作者 Bo Xu Yu Xie Yun Ling Juhua Luo Wei Zhang 《Chinese Chemical Letters》 2025年第7期244-250,共7页
NiMn-MOF was prepared via one-step hydrothermal method,and then Ni/MnO/C composites were synthesized by high-temperature pyrolysis.The findings indicate that the sample acquired at the pyrolysis temperature of 700℃ d... NiMn-MOF was prepared via one-step hydrothermal method,and then Ni/MnO/C composites were synthesized by high-temperature pyrolysis.The findings indicate that the sample acquired at the pyrolysis temperature of 700℃ demonstrate superior microwave absorption capabilities.The minimum reflection value achieves-19.2 dB at a thickness of 1.4mm,and the effective absorption bandwidth extends to 5.04 GHz at a mere 1.6mm.The exceptional microwave absorption proficiency can be ascribed to the multiple reflections and scattering generated by the material’s unique porous spherical structure,optimized impedance matching,suitable conduction loss,rich interfacial and dipole polarization,and magnetic loss.This study presents a straightforward procedural technique for the fabrication of effective composite absorbers. 展开更多
关键词 Magnetic-dielectric synergy Heterogeneous interface engineering Impedance matching Microwave absorption
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Interplay of Temporal Variation in Nectar Parameters and Pollinator-Mediated Adaptations in Epimedium wushanense
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作者 Lanying Chen Yifu Cai +1 位作者 Qiumei Quan Yunxiang Li 《Phyton-International Journal of Experimental Botany》 2025年第5期1519-1532,共14页
This study investigates the diurnal patterns of nectar secretion,sugar content,and caloric value in Epimedium wushanense,and their interaction mechanisms with pollinator behavior under varying environmental conditions... This study investigates the diurnal patterns of nectar secretion,sugar content,and caloric value in Epimedium wushanense,and their interaction mechanisms with pollinator behavior under varying environmental conditions.Nectar secretion exhibited a diurnal pattern,peaking between 11:00 and 13:00,with progressive increases in both volumes(19.07±1.66μL/day)and caloric value(6.03±0.55 cal/day)over four consecutive days,culminating in maximal production on Day 4(p<0.05).Floral bagging significantly altered nectar traits(Mann-Whitney U test,p<0.05),with bagged inflorescences demonstrating 61.82%higher nectar volume productivity relative to unbagged controls.Pollinator visitation,primarily by Bombus trifasciatus and Bombus grahami,was strongly correlated with nectar sugar concentration and distribution,peaking during midday when temperatures and humidity were optimal.Notably,B.trifasciatus displayed legitimate pollination behavior,while B.grahami exhibited nectar robbing.Bombus grahami peaked at 15:00(7.67±0.33 visits)under 22.8°C/58%RH,outperforming Bombus trifasciatus(5.67±0.27 at 13:00;p<0.05),highlighting differential pollinator effectiveness.Temperature negatively impacted unbagged nectar volume and caloric value but positively influenced bagged nectar,suggesting adaptive resource allocation strategies.These findings underscore the intricate relationship between environmental factors,nectar dynamics,and pollinator behavior,revealing how E.wushanense optimizes reproductive success through temporal and ecological adaptations.This study provides critical insights into the ecological mechanisms driving plant-pollinator interactions and resource allocation in changing environments. 展开更多
关键词 Nectar dynamics pollinator behavior environmental adaptation Epimedium wushanense
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Numerical simulation of vortex breakdown in a cylindrical tank with rotating bottom and free surface using level set method
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作者 Zepeng Zhao Qin Li +5 位作者 Feng Ye Haoliang Wang Jianfeng Wang Hui Yu Xiangyang Li Chao Yang 《Chinese Journal of Chemical Engineering》 2025年第1期293-300,共8页
A cylindrical chamber with a rotating bottom holds significant potential for application in cell culture bioreactors due to its ability to generate more stable swirling flows.In order to control vortex breakdown withi... A cylindrical chamber with a rotating bottom holds significant potential for application in cell culture bioreactors due to its ability to generate more stable swirling flows.In order to control vortex breakdown within the chamber,this study first establishes a computational fluid dynamics simulation coupled with the level set method.Verified by experimental results in literature,this method accurately simulates the position and shape of vortex breakdown,and also predicts the critical Reynolds numbers for the appearance and detachment of vortex breakdown bubbles from the center.Additionally,it precisely captures the gas-liquid interface and depicts the vortex breakdown phenomenon in the air above the liquid for the first time.Finally,it predicts the impact of physical property of gas-liquid systems on vortex breakdown in response to significant changes in viscosity of microbial process systems. 展开更多
关键词 Vortex breakdown Level set Microbial cultivation Micro-bioreactor
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Genomic insights into the convergent evolution of desert adaptation in camels and antelopes
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作者 Jiong Zhou Xiao-Fang Zhou +11 位作者 Hui-Shan Yue Wu Chen Bin Li Bo-Tong Zhou Zi-He Li Ze-Cheng Du Yi-Fan Mao Wen Wang Dong-Dong Wu Ge Han Bao Wang Lei Chen 《Zoological Research》 2025年第4期939-952,共14页
Extreme heat and chronic water scarcity present formidable challenges to large desert-dwelling mammals.In addition to camels,antelopes within the Hippotraginae and Alcelaphinae subfamilies also exhibit remarkable phys... Extreme heat and chronic water scarcity present formidable challenges to large desert-dwelling mammals.In addition to camels,antelopes within the Hippotraginae and Alcelaphinae subfamilies also exhibit remarkable physiological and genetic specializations for desert survival.Among them,the critically endangered addax(Addax nasomaculatus)represents the most desert-adapted antelope species.However,the evolutionary and molecular mechanisms underlying desert adaptations remain largely unexplored.Herein,a high-quality genome assembly of the addax was generated to investigate the molecular evolution of desert adaptation in camels and desert antelopes.Comparative genomic analyses identified 136 genes harboring convergent amino acid substitutions implicated in crucial biological processes,including water reabsorption,fat metabolism,and stress response.Notably,a convergent R146S amino acid mutation in the prostaglandin EP2 receptor gene PTGER2 significantly reduced receptor activity,potentially facilitating large-mammal adaptation to arid environments.Lineage-specific innovations were also identified in desert antelopes,including previously uncharacterized conserved non-coding elements.Functional assays revealed that several of these elements exerted significant regulatory effects in vitro,suggesting potential roles in adaptive gene expression.Additionally,signals of introgression and variation in genetic load were observed,indicating their possible influence on desert adaptation.These findings provide insights into the sequential evolutionary processes that drive physiological resilience in arid environments and highlight the importance of convergent evolution in shaping adaptive traits in large terrestrial mammals. 展开更多
关键词 Desert adaptation Convergent evolution Addax nasomaculatus
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