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CKV-Type矩阵和CKV-Type-B矩阵的扩展垂直线性互补问题解的误差估计
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作者 蒋建新 《吉首大学学报(自然科学版)》 2026年第1期6-12,24,共8页
围绕CKV-type矩阵和CKV-type-B矩阵,研究了扩展垂直线性互补问题解的误差界.以“块矩阵任意子块满足2类矩阵定义”为前提,证明了对原块矩阵进行行重排后,得到的新矩阵中每一子块仍保持与原矩阵子块相同的类型,且重排后的矩阵具有行W-性... 围绕CKV-type矩阵和CKV-type-B矩阵,研究了扩展垂直线性互补问题解的误差界.以“块矩阵任意子块满足2类矩阵定义”为前提,证明了对原块矩阵进行行重排后,得到的新矩阵中每一子块仍保持与原矩阵子块相同的类型,且重排后的矩阵具有行W-性质.在此基础上,推导出2类矩阵对应问题解的误差界表达式. 展开更多
关键词 CKV-type矩阵 CKV-type-B矩阵 扩展垂直线性互补问题
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Uniqueness of Positive Solutions to Semilinear Equations with Critical Exponential Nonlinearity of Henon Type
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作者 CEN Jianglin ZHU Maochun 《应用数学》 北大核心 2026年第1期80-89,共10页
In this paper,we study the uniqueness of positive solutions to the following semilinear equations{-Δu=λ|x|^(α)ue^(u^(2)),in B_(1),u=0,onδB_(1)ueu2;in B_(1);u=0;on@B_(1);whereλ>0,α>-2;B_(1)denotes the unit ... In this paper,we study the uniqueness of positive solutions to the following semilinear equations{-Δu=λ|x|^(α)ue^(u^(2)),in B_(1),u=0,onδB_(1)ueu2;in B_(1);u=0;on@B_(1);whereλ>0,α>-2;B_(1)denotes the unit disk in R^(2):By delicate and relatively complicated computation of radial solutions to the above equation and the asymptotic expansion of solutions near the boundary of B_(1),the uniqueness of positive solutions is obtained.The results of this paper extend the uniqueness result for the semilinear equation with critical exponential growth in CHEN et al.(2022)to the case that includes a Henon term. 展开更多
关键词 UNIQUENESS Trudinger-Moser inequality Critical exponential Henon type
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Incorporating multiple scenarios and landscape ecological risk to optimize ecological security patterns: A Wei River Basin case study
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作者 Xueting Wu Jinghu Pan 《Chinese Journal of Population,Resources and Environment》 2026年第1期94-109,共16页
Under the influence of human activities,landscape fragmentation in the Wei River Basin(WRB)has become increasingly severe.Upstream development has intensified soil erosion,and industrial and agricultural pollution in ... Under the influence of human activities,landscape fragmentation in the Wei River Basin(WRB)has become increasingly severe.Upstream development has intensified soil erosion,and industrial and agricultural pollution in the middle reaches has degraded water quality.Rapid urbanization has further caused habitat fragmentation and biodiversity loss.Collectively,these challenges threaten human well-being and hinder sustainable development,making the construction and optimization of an ecological security pattern(ESP)urgently necessary.However,existing studies often fail to systematically integrate future landscape ecological risk(LER)assessment with ESP optimization.This study evaluated regional LER using the“ecological patches-ecological resistance surface(ERS)-ecological corridor”framework,combined with land-use predictions under three development scenarios,and optimized the ESP by adjusting the ERS and extracting ecological corridors.The results indicate that the LER in the WRB follows an“inverted N”distribution,with low-risk areas concentrated in forested mountain regions and high-risk areas mainly in cultivated land subject to intensive human activity.Across future scenarios,ESPs showed fewer ecological breakpoints and improved landscape connectivity than the 2020 baseline.Scenario-based differences emerged in the spatial configuration of ERS adjustments,with the ecological protection scenario yielding the lowest LER and most favorable ESP.This study demonstrates the deep integration of multi-scenario simulation with LER assessment,providing a new framework for ESP optimization.The findings have guiding significance for ecological protection and coordinated development in the WRB and offer a novel paradigm for sustainable development in ecologically fragile basins worldwide. 展开更多
关键词 ecological security pattern Multiple scenarios Landscape ecological risk ecological security pattern optimization
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Railway Expansion and Tourism Transport Ecological Efficiency:Spatial Evidence from China
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作者 Yuxiang Yan Chayanon Phucharoen 《Research in Ecology》 2026年第1期259-273,共15页
Tourism’s link to the Sustainable Development Goals has been a continuing emphasis,adding momentum to longstandingefforts to ensure tourism’s sustainability.Tourism transport is one of the largest sources of anthrop... Tourism’s link to the Sustainable Development Goals has been a continuing emphasis,adding momentum to longstandingefforts to ensure tourism’s sustainability.Tourism transport is one of the largest sources of anthropogenic carbonemissions,driving global ecological change with profound consequences for ecosystem functioning and biodiversity.Large-scale infrastructure projects such as railway expansion are increasingly promoted for their potential to reducetourism-related carbon dioxide emissions,yet their spatial ecological impacts on regional carbon cycles and ecosystemservices remain poorly understood.This study introduces the concept of Tourism Transport Ecological Efficiency(TTEE)to assess the relationship between human infrastructure,carbon emissions,and ecological sustainability.Using panel datafrom China’s railway expansion between 2011 and 2018,the study provides spatially explicit evidence of how transportinfrastructure shapes tourism’s ecological footprint.Results show that non-Eastern regions experienced a greater increasein TTEE(8.7%)compared to Eastern regions(5.5%),highlighting regional disparities in tourism transport ecologicalsustainability.Railway density had a significant positive direct effect on TTEE,particularly pronounced in non-Easternregions.Additionally,a significant indirect effect of railway density in nearby regions was identified.These findings revealthe interconnected ecological impacts of transport systems and underscore the importance of regionally targeted railwayinvestment strategies.By bridging infrastructure development with ecological processes,this study advances understandingof how tourism transport can be aligned with global carbon reduction goals and ecosystem protection. 展开更多
关键词 ecological Efficiency Carbon Footprint ecological Sustainability Ecosystem Protection
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Conservation priority for protected areas in Fuzhou,southeast China:An integrated inside-out approach based on ecological network
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作者 CAI Xinyu XU Zesong +2 位作者 YOU Weibin KATTEL Giri WANG Yingzi 《Journal of Mountain Science》 2026年第1期327-342,共16页
Addressing the widespread issues of internal fragmentation within protected areas and the neglect of surrounding critical habitat networks,this study aims to develop an assessment framework for the precise identificat... Addressing the widespread issues of internal fragmentation within protected areas and the neglect of surrounding critical habitat networks,this study aims to develop an assessment framework for the precise identification and remediation of regional conservation gaps.To this end,we introduce the Framework for Conservation Priority Identification(FCPI).The framework integrates Morphological Spatial Pattern Analysis(MSPA),the Remote Sensing Ecological Index(RSEI),Circuit Theory,and the Minimum Cumulative Resistance(MCR)model to formulate a multidimensional conservation priority index.This index facilitates the identification of critical ecological network components and enables the dynamic prioritization of conservation efforts.A case study of Fuzhou City from 2014 to 2020 reveals that despite an overall improvement in regional environmental quality,the functionality of core ecological sources has markedly declined.Between 2014 and 2020,the number of ecological sources grew by 76.9%,yet their total area shrank by 13.9%.Concurrently,the number of ecological corridors rose from 27 to 53,extending their total length by 380.23 km,which indicates an intensifying trend of habitat fragmentation.Furthermore,a significant number of crucial ecological network nodes,particularly within Minhou County,lie explicitly outside the existing protected area system.This confirms the presence of conservation gaps and unveils the spatiotemporal dynamics of shifting conservation priorities.The research validates that the proposed FCPI can effectively diagnose the dynamic deficiencies within conservation systems.It offers scientific decisionsupport for local governments,facilitating a transition from isolated conservation efforts towards systematic and comprehensive ecological network governance. 展开更多
关键词 Conservation prioritization ecological corridors Protected areas Remote sensing ecological index Landscape connectivity
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Effects of land use type on soil organic carbon in different soil types
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作者 Shunjie Zhu Liangliang Xu +5 位作者 Chengzhong He Yongxing Guo Changqun Duan Xin Jiang Shiyu Li Hailong Yu 《Journal of Integrative Agriculture》 2026年第2期540-552,共13页
Soil organic carbon(SOC)dynamics significantly influence ecosystem carbon source-sink balance,particularly in agroecosystems.However,uncertainty remains regarding optimal land use types for maximizing farmland carbon ... Soil organic carbon(SOC)dynamics significantly influence ecosystem carbon source-sink balance,particularly in agroecosystems.However,uncertainty remains regarding optimal land use types for maximizing farmland carbon storage across different soil types,and identifying effective land management practices for enhanced carbon accumulation is essential for reducing agricultural emissions and strengthening carbon sinks.This study examined SOC variations in eastern Yunnan’s subtropical highlands(2,132 sites),analyzing topsoil(0–20 cm)across five land uses(dryland,irrigated land,forestland,grassland and plantation)of five soil types(red,yellow,yellowbrown,brown,purple).The investigation explored relationships between SOC and edaphic factors(26 elements)to determine SOC influencing factors.The study area demonstrated a mean SOC content of 27.78 g kg^(–1),with distinct spatial heterogeneity characterized by lower values in the southwestern sector and higher concentrations in the northeastern region.Brown soils displayed the highest SOC content(P<0.05),followed by yellow-brown then red,yellow,and purple soils.Irrigation significantly enhanced SOC storage,particularly in brown soils where irrigated land contained 2.2-,2.4-,and 1.6-times higher SOC than forestland,grassland,and dryland,respectively.Similar irrigation benefits occurred in purple,yellow,and yellow-brown soils,indicating moisture limitation as the primary SOC constraint.Notably,SOC exhibited strong positive correlations with nitrogen,sulfur,and selenium.Nitrogen fertilization demonstrated dual benefits:enhancing SOC sequestration and promoting Se enrichment in crops,potentially supporting specialty agriculture.Although land use impacts on SOC varied across soil types(P>0.05),irrigation consistently emerged as the optimal management for carbon sink enhancement.These findings suggest that targeted water management could effectively reduce farmland carbon emissions in moisture-limited subtropical highlands.Strategic nitrogen application offers co-benefits for soil fertility and selenium biofortification,providing practical pathways for climate-smart agriculture in similar ecoregions. 展开更多
关键词 soil organic carbon soil type land use type carbon storage AGROECOSYSTEMS
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Pogorelov type estimates for a class of complex Hessian quotient type equations
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作者 XU Wenzhao CHEN Chuanqiang 《纯粹数学与应用数学》 2026年第1期156-169,共14页
For the complex nonlinear elliptic partial differential equations,it is not easy to prove the Pogorelov type estimates.In this paper,we study a class of complex Hessian quotient type equations in convex cone Γ_(k),wh... For the complex nonlinear elliptic partial differential equations,it is not easy to prove the Pogorelov type estimates.In this paper,we study a class of complex Hessian quotient type equations in convex cone Γ_(k),which is of mixed Hessian type.For the Γ_(k)-admissible solutions,we establish the corresponding Pogorelov estimates with 0≤l<k<n and Pogorelov type estimates with l+1<k=n and l≥0.These extend the previous related results on the real Hessian quotient type equations. 展开更多
关键词 COMPLEX HESSIAN QUOTIENT type EQUATIONS Pogorelov type ESTIMATES Γ_(k)-admissible solutions
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Liu Rui:Forging the“Jiaxing Model”of Aquatic Ecological Governance
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作者 ZHOU LIN 《China Today》 2026年第4期24-28,共5页
Over 20 years,Liu and her team tackled one challenge after another in this Jiaxing“experimental field,”witnessing a historic transformation in water quality.ON March 7,Liu Rui,deputy to the National People’s Congre... Over 20 years,Liu and her team tackled one challenge after another in this Jiaxing“experimental field,”witnessing a historic transformation in water quality.ON March 7,Liu Rui,deputy to the National People’s Congress(NPC),China’s top legislature,vice president of the Yangtze Delta Region Institute of Tsinghua University,Zhejiang(YDRI),and director of its Department of Environmental Technology and Ecology,sat down with China Today during the“two sessions”to share her story of two decades of dedicated work in aquatic ecological governance in the Yangtze River Delta. 展开更多
关键词 Jiaxing model ecological challenges aquatic ecological governance water quality transformation Two Sessions Yangtze River Delta dedicated work environmental technology ecologysat
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Antibiotics in northern China’s largest shallow wetland lake:Occurrence,bioaccumulation,ecological risk,and indicator screening
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作者 Kai Deng Lining Zhao +6 位作者 Meiyu Li Xueyou Liang Xiaobo Wang Jinze Han Yulong Zhang Ryoiti Kiyama Sijun Dong 《Journal of Environmental Sciences》 2026年第1期233-241,共9页
Antibiotics are widespread in aquatic environments due to their extensive use in human healthcare and ani-mal husbandry.However,research on the occurrence and bioaccumulation of antibiotics in aquatic organisms within... Antibiotics are widespread in aquatic environments due to their extensive use in human healthcare and ani-mal husbandry.However,research on the occurrence and bioaccumulation of antibiotics in aquatic organisms within shallow wetland lakes remains limited.This study investigated the occurrence and bioaccumulation of ten commonly used antibiotics in the Baiyang Lake,northern China’s largest shallow wetland lake.The results indicated that sulfonamides and fluoroquinolones were the predominant antibiotics in surface water,whereas fluoroquinolones and macrolides were more prevalent in sediment.Fluoroquinolones demonstrated significant potential for bioaccumulation in targeted aquatic organisms,including both animals and plants(Carassius au-ratus and Phragmites australis).The bioaccumulation of antibiotics in Carassius auratus was correlated with their solubility,whereas in Phragmites australis,this was associated with their octanol-water partition coefficients and molecular weights.Ecological risk assessment indicated that most antibiotics posed minimal to low risk levels.However,four antibiotics were exceptions:clarithromycin(12.5%)and sulfamethoxazole(6.25%)presented a high risk in surface water samples,while norfloxacin(25.0%)and ciprofloxacin(25.0%)posed a high risk in sediment samples.Norfloxacin,ciprofloxacin,and roxithromycin were identified as key indicator antibiotics for enhancing the local monitoring and control of antibiotic contamination based on four criteria:(1)high con-centrations,(2)frequent detection,(3)capacity for bioaccumulation,and(4)ecological risk levels.This study contributes to a deeper understanding of the status of antibiotic contamination,bioaccumulation characteristics,and ecological risk in Baiyang Lake,thereby supporting efforts to monitor and regulate antibiotic pollution. 展开更多
关键词 Baiyang lake ANTIBIOTICS BIOACCUMULATION ecological risk INDICATOR
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Ecological Three-Dimensional Cultivation and Digital Development Model of Xinjiashan Specialty Coffee Base
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作者 Jiangnan WANG Yulian MA +3 位作者 Tingting YANG Caide DUAN Jin'e LI Guangxue YANG 《Plant Diseases and Pests》 2026年第1期22-25,29,共5页
Under the strategic framework of rural revitalization and agricultural modernization, Xinjiashan Specialty Coffee Base, located in Zaotang Village, Lujiang Town, Longyang District, Baoshan City, has been proactively i... Under the strategic framework of rural revitalization and agricultural modernization, Xinjiashan Specialty Coffee Base, located in Zaotang Village, Lujiang Town, Longyang District, Baoshan City, has been proactively investigating innovative models for agricultural development. Through extensive communication and collaboration, this base has established close partnerships with research institutions including Kunming University of Science and Technology, Baoshan University, and Yunnan Academy of Agricultural Sciences, with a commitment to thoroughly exploring the potential for resource recycling and ecological complementarity. An innovative four-in-one three-dimensional integrated planting system incorporating "coffee, bananas, green manure, and bees" has been implemented. Concurrently, technological and digital management strategies have been comprehensively integrated to improve planting efficiency. Under this model, the proportion of specialty coffee attains 71%, and the per-unit yield is 17% greater than that of the conventional planting model. This approach not only substantially enhances economic returns but also promotes the integrated development of ecological and social benefits, offering a valuable practical example and experiential reference for the specialty and sustainable advancement of the coffee industry in comparable regions. 展开更多
关键词 COFFEE Three-dimensional planting DIGITALIZATION ecological cycle Xinjiashan
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Evaluating ecological resilience and enhancement strategies of the strategic hinterlands in western China
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作者 WU Chen 《Ecological Economy》 2026年第1期31-46,共16页
This study comprehensively measures the ecological resilience level of seven provinces in the strategic hinterland of Western China during 2013-2023.It constructs an ecological resilience evaluation system covering th... This study comprehensively measures the ecological resilience level of seven provinces in the strategic hinterland of Western China during 2013-2023.It constructs an ecological resilience evaluation system covering the three dimensions of"Resistance-Adaptability-Recovery"and adopts the entropy-weighted TOPSIS method for objective weighting and comprehensive ranking.The results show that:(1)The overall ecological resilience of the strategic hinterlands in Western China presents a steady upward trend,evolving from a low resilience level to a medium resilience range over the decade,with continuous investment in ecological governance and institutional supply gradually transformed into resilience enhancement effects in the long run;(2)Ecological resilience exhibits a typical pattern characterized by"high-level stability of Resistance,continuous improvement of Recovery,and relative lag of Adaptability,"among which Recovery shows the most remarkable growth rate,while Adaptability fluctuates significantly and constitutes a key bottleneck for overall leapfrog development;(3)As core carrying areas,Sichuan and Shaanxi perform outstandingly,and Guizhou demonstrates a remarkable upward momentum,while Qinghai,Ningxia,Gansu and other regions still face constraints such as limited ecological governance capacity and relatively strong structural pressures.Based on the differentiated evolutionary characteristics of the three dimensions,the study proposes enhancement paths including constructing a cross-regional ecological security barrier,breaking through the bottleneck of Adaptability,and driving high-quality resilient growth with Recovery. 展开更多
关键词 strategic hinterlands ecological resilience resistance ADAPTABILITY RECOVERY
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Earth’s New Horizon:Innovations in Ecological Development and Environmental Preservation
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作者 Haitao Wang Xuan Zhang Zhaojun Wu 《Journal of Environmental & Earth Sciences》 2026年第1期298-323,共26页
The environment and its preservation are becoming more and more dependent on ecological development in an age of accelerating climate risk,biodiversity loss,and pressures of pollution.This review summarizes the fronti... The environment and its preservation are becoming more and more dependent on ecological development in an age of accelerating climate risk,biodiversity loss,and pressures of pollution.This review summarizes the frontiers of innovation that are capable of enhancing integration of human development and ecological integrity,and how the interaction between technical,ecological,and institutional innovations can produce real-world results.We initially discuss developing ecological innovations that offer new opportunities to urban development,such as low-impact cities,ecological infrastructure,clean energy transitions,and biodiversity-informed siting,and digital decision-support systems enhancing planning and resource efficiency.Then,we evaluate progress in the field of preservation and restoration,with a particular focus on nature-based solutions,a process-based approach to restoration science,connectivity conservation,and a watershed-scale and seascape-scale approach to restore resilience and help recover biodiversity.In these spheres,we discover measurement,monitoring,and verification(MRV),one of the main pillars of scale alongside remote sensing,automated field monitoring,environmental Deoxyribonucleic Acid(DNA),and Artificial Intelligence(AI)-enabled analytics,increasing the range of trackable and manageable indices as well as creating new issues with baselines,uncertainty,and data ethics.Lastly,we compare governance,finance,and equity as key conversion processes that can turn innovations into sustainable dividends with authenticity principles,however,of additionality,permanence,and leakage avoidance,and with rightsbased and redistributive mechanisms and approaches that reinforce legitimacy.We end by providing a portfolio roadmap of prioritization of the interventions that have high co-benefits and the identification of critical research and institutional gaps to provide net-positive ecological results. 展开更多
关键词 ecological Development Environmental Preservation Nature-Based Solutions MRV Circular Economy
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Evaluation of ecological environmental quality and its driving factors in a mountain basin:A case study of the Manas River Basin,China
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作者 QI Wenwen LI Yuanyuan SHI Xiang 《Journal of Arid Land》 2026年第4期608-631,共24页
In recent years,intensified land use change driven by climate change and human activities have markedly impacted the ecological environmental quality of the arid inland river basins.The implementation of forestry proj... In recent years,intensified land use change driven by climate change and human activities have markedly impacted the ecological environmental quality of the arid inland river basins.The implementation of forestry projects,coupled with continuous population growth,has increased the need for systematic assessments of ecological effects to ensure sustainable development in arid inland river basins.This study generated a 22-a(2000-2021)remote sensing ecological index(RSEI)data series for the Manas River Basin,a typical arid inland river basin in China,utilizing Moderate Resolution Imaging Spectroradiometer(MODIS)data and the Google Earth Engine(GEE)platform.We examined the spatiotemporal patterns of ecological environmental quality in the Manas River Basin through the Theil-Sen estimator,Mann-Kendall trend test,coefficient of variation(CV),and Hurst index.Furthermore,we employed the Optimal Parameter-based Geographical Detector(OPGD)method to quantify the influence of seven key drivers:elevation,slope,temperature,precipitation,gross domestic product(GDP),population density,and land use change.The key findings revealed that the basin's ecological environmental quality showed significant improvement(mean RSEI of 0.38,with a range of 0.34-0.41),with areas exhibiting good and excellent grades increasing by 16.71%,particularly in the midstream oasis region and upstream mountainous region,while areas exhibiting poor and relatively poor grades decreased by 11.52%in the downstream desert region.Spatial heterogeneity of ecological environmental quality was pronounced,with 32.23%of the areas showing localized degradation,the midstream oasis region exhibiting sustainable recovery potential(Hurst index>0.50),and only 36.67%of the areas maintaining stable and highly stable conditions(primarily in the upstream mountainous region).The OPGD analysis revealed that temperature(q-value=0.496-0.780),land use change(q-value=0.705-0.782),and elevation(q-value=0.245-0.637)were dominant factors,with the influence of land use change increasing during 2000-2020.Strong interaction effects emerged between land use change and temperature(q-value>0.705)and between land use change and elevation(q-value=0.751 in 2020),highlighting intensified human-nature coupling.These findings provide vital perspectives for ecosystem management in arid inland river basins under both climate and anthropogenic pressures. 展开更多
关键词 ecological environment quality land use change remote sensing ecological index(RSEI) Google Earth Engine(GEE) Optimal Parameter-based Geographical Detector(OPGD) mountain-oasis-desert system
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Effects of Ecological Ditch and Wetland in Reducing Farmland Drainage Pollutants in Hetao Irrigation District
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作者 Zhen HU Qiong LIAO +4 位作者 Xu LI Wei QIAO Xiang ZENG Yongbing HUANG Wei REN 《Asian Agricultural Research》 2026年第1期25-32,共8页
[Objectives]To explore the control mode of farmland drainage pollutants and investigate the effects of ecological ditch and wetland on reducing farmland drainage pollutants in Hetao Irrigation District.[Methods]Based ... [Objectives]To explore the control mode of farmland drainage pollutants and investigate the effects of ecological ditch and wetland on reducing farmland drainage pollutants in Hetao Irrigation District.[Methods]Based on the demonstration construction project of the ecological ditch-constructed wetland system in the Hetao Irrigation District,an experimental study was conducted from July to September 2023 to investigate the interception and purification effects of ecological ditches,constructed wetlands,and the combined ecological ditch-constructed wetland system on farmland drainage pollutants.Key water quality parameters measured included total nitrogen(TN)concentration and total phosphorus(TP)concentration.[Results]Different treatment modes of ecological ditches and constructed wetlands have a certain removal effect on nitrogen and phosphorus pollutants in water bodies.The ecological ditches treated with Astragalus laxmannii,Melilotus officinalis,Medicago sativa,bio-ball substrate,and bio-sheet substrate showed reduction efficiencies for TN and TP of 21.09% and 23.84%,12.06% and 26.67%,20.08% and 34.15%,23.65% and 20.56%,and 19.92% and 25.83%,respectively.The emergent plant area showed reduction efficiencies of 24.28%for TN and 17.89%for TP,while the submerged plant area achieved a reduction efficiency of 10.21%for both TN and TP.Among the different treatment modes,the ecological ditch with M.sativa performed better in TP removal,whereas the bio-ball substrate treatment mode showed higher effectiveness in TN removal.In addition,the emergent plant area exhibited better TP removal performance,while the submerged plant area was more effective in TN removal.The combined system of ecological ditch and constructed wetland achieved removal rates of 37.55% for TN and 11.47% for TP.It effectively facilitates the step-by-step interception and adsorption purification of pollutants,thereby showing significant removal and purification effects on nitrogen and phosphorus contaminants.This contributes to mitigating agricultural non-point source pollution.[Conclusions]The combined ecological ditch-constructed wetland system serves dual functions of agricultural drainage and pollutant interception and purification.It reduces the pollution load of farmland drainage on receiving water bodies to some extent and mitigates agricultural non-point source pollution.Therefore,it is a relatively suitable technology for managing agricultural non-point source pollution in the Hetao Irrigation District. 展开更多
关键词 ecological ditch Constructed wetland POLLUTANT Purification effect Hetao Irrigation District
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Impact of Typhoon Bolaven on the Ecological Characteristics of the East China Sea and the Yangtze River Estuary
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作者 FANG Chen-yu ZHANG Wen-zhou +4 位作者 MA Zhan-hong ZHAO Kai ZHENG Yun-xia ZHENG Hui FEI Jian-fang 《Journal of Tropical Meteorology》 2026年第1期33-46,共14页
Typhoons are strong air–sea interactions that significantly affect the physical and biogeochemical processes of the upper ocean. Based on the Regional Ocean Modeling System-Carbon–Silicate–Nitrate Ecosystem coupled... Typhoons are strong air–sea interactions that significantly affect the physical and biogeochemical processes of the upper ocean. Based on the Regional Ocean Modeling System-Carbon–Silicate–Nitrate Ecosystem coupled model, the influence of Typhoon Bolaven(2012) on physical and ecological variables in the East China Sea and the underlying mechanisms were investigated. The results showed that the typhoon induced intense vertical mixing in the upper ocean,leading to sea surface cooling, increased salinity, nutrient concentrations, and phytoplankton blooms. Conversely, warming,reduced salinity, and decreased nutrient concentrations occurred in the subsurface layer. In the Yangtze River Estuary, the passage of typhoons effectively affected wind and current directions, shaping the dipole distribution patterns of the environmental elements. Diagnostic analysis indicated that tropical cyclone-induced horizontal advection is key in driving changes in both the physical and ecological variables within the estuary region. This study provides novel insights into the physical-ecological coupling processes and driving mechanisms governing oceanic environmental changes during typhoon events, particularly in the waters adjacent to the Yangtze River Estuary. 展开更多
关键词 TYPHOON ecological environment ocean response the Yangtze River Estuary
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Unveiling the medicinal and ecological value of Ceratopteris thalictroides(L.)Brongn:a systematic review of its phytochemical and pharmacological activities
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作者 Thannikkappilly Johny Siyamol Antoneyraj Mary Saral 《Traditional Medicine Research》 2026年第6期1-19,共19页
Ceratopteris thalictroides (L.) Brongn (C. thalictroides), a fern from the Pteridaceae family, isan edible species that remains largely underutilized, even though it possesses a diverserange of applications. This revi... Ceratopteris thalictroides (L.) Brongn (C. thalictroides), a fern from the Pteridaceae family, isan edible species that remains largely underutilized, even though it possesses a diverserange of applications. This review aims to provide a comprehensive overview of itsgeographical distribution, ethnomedicinal applications, phytochemical constituents,pharmacological activities, and ecological importance. Various phytochemical analysesidentified the presence of phenols, flavonoids, alkaloids, terpenoids, and fatty acids from C.thalictroides, responsible for its multiple pharmacological properties, including antioxidant,antimicrobial, anti-inflammatory, anti-diabetic, and anticancer activities. Additionally, itsunique antheridiogen activity makes it a valuable model organism for plant genetics andreproductive studies. This review systematically summarizes the phytopharmacologicalpotential and ecological significance of C. thalictroides. The plant holds promise as a sourceof novel therapeutics and as a sustainable bioresource for pharmaceutical andenvironmental applications. 展开更多
关键词 Ceratopteris thalictroides(L.)Brongn ECOLOGY ethnomedicinal PHARMACOLOGY PHYTOCHEMISTRY
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Grassland ecosystems of Tajikistan:Plant species diversity,ecological restoration,and sustainable management
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作者 Hikmat HISORIEV LI Yaoming +3 位作者 HUANG Wenjun FAN Lianlian Mekhrovar OKHONNIYOZOV MA Xuexi 《Regional Sustainability》 2026年第1期23-36,共14页
Livestock farming is a critical pillar of Tajikistan’s national economy and livelihood security.However,significant economic challenges in the country have led to the degradation of grassland ecosystems.This degradat... Livestock farming is a critical pillar of Tajikistan’s national economy and livelihood security.However,significant economic challenges in the country have led to the degradation of grassland ecosystems.This degradation has not only reduced the productivity of grassland ecosystems but also severely impacted their ecological functions.A particularly concerning consequence is the threat to biodiversity,as the survival and persistence of endemic,rare,and endangered plant species are at serious risk,thereby diminishing the value of species’genetic resources.Based on the data from multiple sources such as literature reviews,field observations,and national statistics,this study employed a systematic literature review and meta-analysis to investigate the current status,causes of degradation,and restoration measures for grassland ecosystems in Tajikistan.The results revealed that Tajikistan’s grassland ecosystems support exceptionally high plant species diversity,comprising over 4500 vascular plant species,including nearly 1500 endemic and sub-endemic taxa that constitute a unique genetic reservoir.These ecosystems are experiencing severe degradation,characterized by significantly reduced vegetation cover and declining species richness.Palatable forage species are increasingly being displaced by unpalatable,thorny,and poisonous species.The primary drivers of degradation include excessive grazing pressure,which disrupts plant reproductive cycles and regeneration capacity,habitat fragmentation due to urbanization and infrastructure development,and uncontrolled exploitation of medicinal and edible plants.Climate change,particularly rising temperatures and altered precipitation patterns,further exacerbates these anthropogenic pressures.Ecological restoration experiments suggested that both ecosystem productivity and plant species diversity are significantly enhanced by systematic reseeding trials using altitude-adapted native species.These findings underscore the necessity of establishing scientifically grounded approaches for ecological restoration. 展开更多
关键词 Grassland ecosystem degradation Plant communities OVERGRAZING ecological restoration Climate change TAJIKISTAN
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Inadequate glycemic control among patients with type 2 diabetes in Jordan:prevalence and associated factors
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作者 Abeer Amin Mohammad Jafar Alshraideh +1 位作者 Mohammed Ibrahim Yacoub Mohammad A.Abu Sabra 《Frontiers of Nursing》 2026年第1期131-138,共8页
Background:Diabetes mellitus(DM)is a chronic illness with potentially fatal and debilitating consequences.Problems with glycemic management are a major issue that adds an added strain to public health services.Objecti... Background:Diabetes mellitus(DM)is a chronic illness with potentially fatal and debilitating consequences.Problems with glycemic management are a major issue that adds an added strain to public health services.Objectives:The purpose of this study is to evaluate the prevalence of poor glycemic control and its related variables among type 2 diabetes mellitus(T2DM)patients in southern Jordan.Methods:A cross-sectional study was carried out in the Prince Hashem bin Abdullah II Hospital in Jordan's southernmost province.For the period April–July 2024,516 individuals with T2D were enrolled.A structured questionnaire that had been pre-prepared was used to collect data.As an index of glycemic control,a glycated hemoglobin(Hb A1c)7%cut-off point was adopted.Results:Poor glycemic control was prevalent in 81.0%of T2DM individuals.Inadequate glycemic control was significantly worse in non-married patients and those with 10 or more years of diabetes duration,insulin treatment,dyslipidemia,neuropathy,cardiovascular illness,and glomerular filtration rate(GFR=60 m L/min;[P<0.05]).Moreover,dyslipidemia and insulin administration increased the likelihood of poor glycemic control(odds ratio[OR]:2 and 5,respectively)(P<0.05).Conclusions:Inadequate glycemic control was common among the current study par ticipants.To prevent disease consequences and enhance the health of patients with diabetes,health care professionals should pay special attention to related risk factors such as dyslipidemia,neuropathy,cardiovascular disease(CVD),extended illness duration,and insulin usage. 展开更多
关键词 diabetes management glycemic control JORDAN type 2 diabetes
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Spatial morphology optimization for reconciling urban expansion with ecological integrity based on a multi-level ecological network framework
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作者 LU Jie JIAO Sheng CHEN Xingli 《Journal of Geographical Sciences》 2026年第2期399-420,共22页
Urban spatial morphology(USM)optimization is critical to balancing biodiversity conservation and sustainable urbanization.However,previous studies predominantly focused on the socio-economic efficiency and static ecol... Urban spatial morphology(USM)optimization is critical to balancing biodiversity conservation and sustainable urbanization.However,previous studies predominantly focused on the socio-economic efficiency and static ecological metrics and rarely addressed the dynamic USM optimization across spatial scales.Here,we developed a multi-level ecological network(MEN)framework to resolve the tension between urban expansion and ecological integrity.By integrating the cost-weighted distance analysis with a hierarchical network transmission mechanism,we established a cross-scale spatial optimization system,which coordinated the regional ecological corridors and local habitat patches.Comparative experiments with conventional single-scale approaches and scenario simulations using the PLUS model show that the MEN framework had superior performance in three dimensions:(1)spatial governance:the primary-level network(peri-urban natural reserves)effectively contained urban sprawl,and the secondary-level network(intra-urban green corridors)mitigated habitat fragmentation and improved the built-environment;(2)scenario robustness:the model maintained an optimal compactness-loose balance in multiple development pathways;(3)landscape metrics:patch fragmentation decreased by 18.25%,and the internal landscape richness improved by 10.66%compared to the scenario without USM optimization.The findings provide new insight to establish a hierarchical ecological optimization framework as a nature-based spatial protocol to reconcile metropolitan growth with landscape sustainability. 展开更多
关键词 urban spatial morphology ecological network multi-level coupling scenarios simulation urban expansion
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Genotypes and antibiotic resistance characteristics of Clostridioides difficile in children under 5 years in Yunnan Province,2013-2019
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作者 Jiao Gong Lin-Xia Guo +1 位作者 Yan Zhang Wen-Peng Gu 《Infection Advances》 2026年第2期23-28,共6页
Background:This study aims to analyze the genotypes and antibiotic resistance characteristics of Clostridioides difficile(C.difficile)isolated from children under 5 years old with diarrhea in Yunnan Province.Methods:F... Background:This study aims to analyze the genotypes and antibiotic resistance characteristics of Clostridioides difficile(C.difficile)isolated from children under 5 years old with diarrhea in Yunnan Province.Methods:Fecal samples from children under 5 years of age with diarrhea in Kunming city from 2013-2019 were collected for anaerobic culture,isolation,and identification of C.difficile.The antibiotic susceptibility tests and molecular typing of isolated strains were also performed.Results:44 strains of C.difficile were isolated from 896 fecal samples.Of these,40 strains(90.9%)were positive for both tcdA and tcdB,while 4 strains(9.1%)were negative for both.All isolates were negative for cdtA and cdtB.The isolates were classified into 13 STs,the predominant types were ST3(13 strains,29.5%),ST35(8 strains,18.2%),and ST54(5 strains,11.4%).All the strains were susceptible to metronidazole,amoxicillin/clavulanic acid,vancomycin,and amoxicillin.The highest resistance rate was observed against gentamicin(86.36%),followed by polymyxin E(84.09%),quinupristin-dalfopristin(61.36%),and ceftazidime(36.36%).Some patients with diarrhea had C.difficile co-infections with other pathogens,including norovirus,adenovirus,rotavirus or Salmonella or Escherichia coli.Conclusion:C.difficile strains isolated from children under 5 years of age are mostly toxigenic,and the MLST results are highly diverse.Monitoring and prevention of C.difficile should be strengthened. 展开更多
关键词 Clostridioides difficile CHILDREN DIARRHEA antibiotic resistance multilocus sequence typing
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