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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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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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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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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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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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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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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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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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Assessment of Chinese urban land-use efficiency(SDG11.3.1)utilizing high-precision urban built-up area data
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作者 Hao Wang Yafei Liu +2 位作者 Lianze Sun Xiaogang Ning Guangzhe Li 《Geography and Sustainability》 2025年第1期58-74,共17页
Assessment of SDG11.3.1 indicator of the United Nations Sustainable Development Goals(SDGs)is a valuable tool for policymakers in urban planning.This study aims to enhance the accuracy of the SDG11.3.1 evaluation and ... Assessment of SDG11.3.1 indicator of the United Nations Sustainable Development Goals(SDGs)is a valuable tool for policymakers in urban planning.This study aims to enhance the accuracy of the SDG11.3.1 evaluation and explore the impact of varying precision levels in urban built-up area on the indicator’s assessment outcomes.We developed an algorithm to generate accurate urban built-up area data products based on China’s Geographical Condition Monitoring data with a 2 m resolution.The study evaluates urban land-use efficiency in China from 2015 to 2020 across different geographical units using both the research product and data derived from other studies utilizing medium and low-resolution imagery.The results indicate:(1)A significant improvement in the accuracy of our urban built-up area data,with the SDG11.3.1 evaluation results demonstrating a more precise reflection of spatiotemporal characteristics.The indicator shows a positive correlation with the accuracy level of the built-up area data;(2)From 2015 to 2020,Chinese prefecture-level cities have undergone faster urbanization in terms of land expansion relative to population growth,leading to less optimal land resource utilization.Only in extra-large cities does urban population growth show a relatively balanced pattern.However,urban popula tion growth in other regions and cities of various sizes lags behind land urbanization.Notably,Northeast China and small to medium cities encounter significant challenges in urban population growth.The comprehensive framework developed for evaluating SDG11.3.1 with high-precision urban built-up area data can be adapted to different national regions,yielding more accurate SDG11.3.1 outcomes.Our urban area and built-up area data products provide crucial inputs for calculating at least four indicators related to SDG11. 展开更多
关键词 SDG11.3.1 Land-use efficiency Urban built-up area URBANIZATION Population growth
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Seismic Prediction Methods for Tidal Flat Sand Bodies in the Shunbei Area of the Tarim Basin
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作者 Zhi-peng Sun Rui-zhao Yang +4 位作者 Jing-rui Chen Hao Zhang Shi-jie Zhang Peng-hui Yang Feng Geng 《Applied Geophysics》 2025年第1期176-196,235,共22页
The Tarim Basin has revealed numerous tight sandstone oil and gas reservoirs.The tidal fl at zone in the Shunbei area is currently in the detailed exploration stage,requiring a comprehensive description of the sand bo... The Tarim Basin has revealed numerous tight sandstone oil and gas reservoirs.The tidal fl at zone in the Shunbei area is currently in the detailed exploration stage,requiring a comprehensive description of the sand body distribution characteristics for rational exploration well deployment.However,using a single method for sand body prediction has yielded poor results.Seismic facies analysis can eff ectively predict the macro-development characteristics of sedimentary sand bodies but lacks the resolution to capture fine details.In contrast,single-well sedimentary facies analysis can describe detailed sand body development but struggles to reveal broader trends.Therefore,this study proposes a method that combines seismic facies analysis with single-well sedimentary microfacies analysis,using the lower section of the Kepingtage Formation in the Shunbei area as a case study.First,seismic facies were obtained through unsupervised vector quantization to control the macro-distribution characteristics of sand bodies,while principal component analysis(PCA)was applied to improve the depiction of fine sand body details from seismic attributes.Based on 3D seismic data,well-logging data,and geological interpretation results,a detailed structural interpretation was performed to establish a high-precision stratigraphic framework,thereby enhancing the accuracy of sand body prediction.Seismic facies analysis was then conducted to obtain the macro-distribution characteristics of the sand bodies.Subsequently,core data and logging curves from individual wells were used to clarify the vertical development characteristics of tidal channels and sandbars.Next,PCA was employed to select the seismic attributes most sensitive to sand bodies in diff erent sedimentary facies.Results indicate that RMS amplitude in the subtidal zone and instantaneous phase in the intertidal zone are the most sensitive to sand bodies.A comparative analysis of individual seismic attributes for sand body characterization revealed that facies-based delineation improved the accuracy of sand body identification,eff ectively capturing their contours and shapes.This method,which integrates seismic facies,single-well sedimentary microfacies,and machine learning techniques,enhances the precision of sand body characterization and off ers a novel approach to sand body prediction. 展开更多
关键词 Shunbei area Seismic Facies Vector Quantization PCA Sandstone prediction
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Acquired cutaneous fistula in the periocular area:A case report
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作者 Bijnya Birajita Panda Anmol Kar +1 位作者 Thilakraj Koppalu Lingaraju Pavithra Ayyanar 《World Journal of Clinical Cases》 2025年第31期76-82,共7页
BACKGROUND Lacrimal sac rhinosporidiosis,with nil or minor nasal extensions,rarely presents as an acquired cutaneous fistula in the periocular area.The correct diagnosis in such cases can be challenging,leading to rep... BACKGROUND Lacrimal sac rhinosporidiosis,with nil or minor nasal extensions,rarely presents as an acquired cutaneous fistula in the periocular area.The correct diagnosis in such cases can be challenging,leading to repeated failure of conservative or surgical interventions.CASE SUMMARY A 39-year-old female presented with a 6-year history of swelling in the periocular area,specifically in the left lacrimal sac area.Symptoms were limited to epiphora and constant mucoid discharge from the fistula,clinically mimicking chronic lacrimal sac fistula.She had a history of treatment with multiple antibiotic courses and dacryocystectomy in the past,with no or transient symptomatic relief.On surgical exploration of the site,a large pedunculated polypoidal vascular mass,suspicious of rhinosporidiosis,was noted.En bloc resection of the mass with cauterization of the base and fistulectomy was performed.Histopathology confirmed the diagnosis of lacrimal sac rhinosporidiosis.The patient was further evaluated and treated for the nasal extension of rhinosporidiosis.The patient has been frequently followed up for the last 3 years with a good clinical outcome and no recurrence.CONCLUSION Lacrimal sac rhinosporidiosis,in isolated or limited nasal extension cases,can rarely mimic a chronic discharging fistula.Patients with this disease often face distress due to misdiagnosis and repeated failure of conservative or surgical interventions.A high index of suspicion is needed for early diagnosis.Proper surgical intervention at the right time can lead to an excellent prognosis in such patients. 展开更多
关键词 Lacrimal sac fistula Ocular rhinosporidiosis EPIPHORA Periocular area Case report
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Reservoir characteristics and distribution of the Majiagou Formation in the Fuxian area of Ordos Basin, China
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作者 Ning Gu Juntao Zhang +3 位作者 Xiaohui Jin Jiaqi Yang Fei Yang Lu Liu 《Energy Geoscience》 2025年第1期56-67,共12页
The Majiagou Formation in the Fuxian area of the southeastern Ordos Basin has undergone a complex diagenetic evolution history under the influence of eustacy and the Caledonian karstification,resulting in several comp... The Majiagou Formation in the Fuxian area of the southeastern Ordos Basin has undergone a complex diagenetic evolution history under the influence of eustacy and the Caledonian karstification,resulting in several complex reservoir types.Through analyses of mineralogy,petrology,and reservoir geology,three major types of dolomite reservoirs with different genetic mechanisms,including anhydritic moldicdissolved pore type,dolomitic intercrystalline-pore type,and fractured type were identified,and their formation mechanisms and distribution patterns were examined.The aphanocrystalline to very finecrystalline anhydritic dolomite was resulted from Sabhak dolomitization,and is characterized by small size of crystals and high content of anhydrite.Dolomite reservoirs of anhydritic moldic-dissolved pore type were developed in multi-stage dissolution processes and mainly distributed at higher positions of the paleogeomorphology where the filling was weak.The very fine to fine-crystalline dolomite of shoal facies was formed under seepage-reflux dolomitization,and characterized by larger sizes of crystals and well-developed intercrystalline pores.Dolomite reservoirs of intercrystalline-pore type were mainly developed at the lower positions of the paleogeomorphology where bedding-parallel karst dissolution was strong.The fractured dolomite reservoirs,generated by the anhydrite swelling and karst cave collapse,occur in multiple horizons but within limited areas due to multi-stage fillings. 展开更多
关键词 Anhydritic moldic pore DOLOMITE Majiagou Formation Fuxian area Ordos Basin
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A general methodological framework for hazard assessment in remote mountain areas combining geomorphological mapping with UAV survey
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作者 Elena GAROVA Bogdan CHADROMTSEV +6 位作者 Alexander PEDANOV Pavel GREBENNIKOV Igor ILTUGANOV Pavel LOBANOV Pavel PONOMARJOVS Felix DRAESNER Sven FUCHS 《Journal of Mountain Science》 2025年第3期763-775,共13页
This paper presents a standardised workflow for conducting hazard assessments of mass wasting processes in remote mountain areas with limited data.The methodology integrates geomorphological mapping and remote sensing... This paper presents a standardised workflow for conducting hazard assessments of mass wasting processes in remote mountain areas with limited data.The methodology integrates geomorphological mapping and remote sensing techniques and is adaptable to different national standards,thus ensuring its applicability in a variety of contexts.The principal objective is to guarantee the safety of mountainous regions,particularly in the vicinity of essential infrastructure,where the scope for implementing structural measures is restricted.The framework commences with comprehensive geomorphological mapping,which facilitates the identification of past hazardous processes and potential future hazards.New technologies,such as uncrewed aerial vehicles(UAVs),are employed to create high-resolution DEMs,which are particularly beneficial in regions with limited data availability.These models facilitate the assessment of potential hazards and inform decisions regarding protective measures.The utilisation of UAVs enhances the accuracy and efficiency of data collection,particularly in remote mountainous regions where alternative remotely sensed information may be unavailable.The integration of modern approaches into traditional hazard assessment methods allows for a comprehensive analysis of the spatial distribution of factors driving mass wasting processes.This workflow provides valuable insights that assist in the prioritisation of interventions and the optimisation of risk reduction in high mountainous areas. 展开更多
关键词 Geomorphological mapping Hazard assessment UAV Remote mountain areas Mitigation planning
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