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塞尔维亚北部末次间冰期古土壤的磁性增强机理:以Ruma和Titel黄土剖面为例
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作者 刘植 何瑞娜 +2 位作者 朱迎雪 Slobodan B Marković 刘秀铭 《地球环境学报》 2025年第4期460-472,513,共14页
塞尔维亚北部的Vojvodina地区是东欧黄土的重要分布区,对该地区著名的Ruma和Titel剖面的末次间冰期古土壤及其下覆黄土层进行多种环境磁学参数的分析对比。结果显示:两个剖面末次间冰期古土壤的磁学性质基本一致,可以代表Vojvodina地区... 塞尔维亚北部的Vojvodina地区是东欧黄土的重要分布区,对该地区著名的Ruma和Titel剖面的末次间冰期古土壤及其下覆黄土层进行多种环境磁学参数的分析对比。结果显示:两个剖面末次间冰期古土壤的磁学性质基本一致,可以代表Vojvodina地区末次间冰期古土壤地层磁性变化的整体情况,其所含磁性矿物的种类与中国黄土相似,有亚铁磁性的磁铁矿和磁赤铁矿,以及反铁磁性的赤铁矿和针铁矿。成壤过程中形成的细粒亚铁磁性矿物是Vojvodina地区末次间冰期古土壤磁性增强的主要原因。相对于中国黄土高原,Vojvodina地区末次间冰期古土壤的成壤环境可能更为湿润,但其磁性增强的幅度却小得多,对该差异的进一步研究可能有助于深入理解黄土磁性变化的成壤模式机理。 展开更多
关键词 东欧黄土 磁化率 环境磁学 古环境变化
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中欧黄土中古土壤S_(5)的磁性特征对比
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作者 朱迎雪 刘植 +3 位作者 郭雪莲 何瑞娜 刘秀铭 Slobodan B Marković 《地球环境学报》 2025年第4期473-483,共11页
S_(5)古土壤是中国黄土剖面中的重要标志层,对中国黄土高原宝鸡剖面和塞尔维亚北部Stari Slankamen剖面的古土壤S_(5)及其下覆黄土层L_(6)进行多种环境磁学参数的对比分析,探讨二者磁学性质的异同点。结果表明:两个古土壤层磁性增强的... S_(5)古土壤是中国黄土剖面中的重要标志层,对中国黄土高原宝鸡剖面和塞尔维亚北部Stari Slankamen剖面的古土壤S_(5)及其下覆黄土层L_(6)进行多种环境磁学参数的对比分析,探讨二者磁学性质的异同点。结果表明:两个古土壤层磁性增强的主导因素是成壤作用,所含磁性矿物有亚铁磁性的磁铁矿和磁赤铁矿,以及反铁磁性的赤铁矿和针铁矿。湿润的成壤环境可能是两个古土壤层中针铁矿含量较多和磁赤铁矿含量较少的原因,也是导致二者低磁化率现象的原因之一。综合古土壤形态和磁学性质的多方面差异,Stari Slankamen剖面S_(5)古土壤的磁性增强属于通常认为的氧化环境下的成壤作用所致,而宝鸡剖面S_(5)古土壤则是过度湿润的成壤环境导致的潜育化作用的结果。 展开更多
关键词 环境磁学 磁化率 成壤作用 古气候变化
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Inventory and assessment of geomorphosites of Mountainous Phrygia(Eskişehir/Türkiye)
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作者 ÖZDEMİR M.Ali KAYMAK Hülya 《Journal of Mountain Science》 2025年第7期2313-2331,共19页
Seyitgazi and Han districts,located in the south of Eskişehir in Central Anatolia,in western Türkiye,host interesting landforms,such as steep slopes,mesas and butte structures,fault-guided slopes,valleys,fairy ch... Seyitgazi and Han districts,located in the south of Eskişehir in Central Anatolia,in western Türkiye,host interesting landforms,such as steep slopes,mesas and butte structures,fault-guided slopes,valleys,fairy chimneys,castle koppies,pillars,weathered rock blocks,perched rocks,cavernous weathering features,grooves,and gnammas,formed on tuffs in semi-arid to semi-humid climatic conditions,as well as geoarchaeological remains belonging to various civilisations,primarily the Phrygians(including rock-cut tombs and settlements,fortresses,rock churches,façades,altars,and niches).This study aims at identifying these remarkable landforms that host cultural heritage and revealing the geoheritage value and geotourism potential of the region.The data obtained from the fieldwork were evaluated using the methodology proposed by Pereira and Pereira in 2010,and 26 geomorphosites were selected from 61 potential sites using this method.The analysis results revealed that although the region hosts numerous geomorphosites with high scientific,cultural,aesthetic,and ecological value,the overall levels of protection and touristic use of these landforms are generally low.Indeed,the area,which has the potential to be an important tourism region in the future,faces problems such as infrastructure deficiencies,transportation difficulties,lack of promotion,weaknesses in accommodation services,and destruction of geoheritage.These results highlight the importance of implementing sustainable geotourism strategies that are compatible with the region’s unique geoheritage.In this respect,this study is among the first to comprehensively inventory and assess the geomorphosites of Mountainous Phrygia,contributing to regional geoconservation and sustainable tourism development. 展开更多
关键词 Geomorphosites INVENTORY ASSESSMENT Mountainous Phrygia Eskişehir Türkiye
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Doline susceptibility mapping using multisource data in the karst aquifers of Saldaran mountain,High Zagros Belt
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作者 Peyman MOHAMMADI-AHMADMAHMOUDI Somaiyeh KHALEGHI Mohsen EHTESHAMI-MOINABADI 《Journal of Mountain Science》 2025年第2期422-435,共14页
Doline susceptibility mapping(DSM)in karst aquifer is important in terms of estimating the vulnerability of the aquifer to pollutants,estimating the infiltration rate,and infrastructures exposed to the development of ... Doline susceptibility mapping(DSM)in karst aquifer is important in terms of estimating the vulnerability of the aquifer to pollutants,estimating the infiltration rate,and infrastructures exposed to the development of dolines.In this research,doline susceptibility map was prepared in Saldaran mountain by generalized linear model(GLM)using 14 affecting parameters extracted from satellite images,digital elevation model,and geology map.Only 8 parameters have been inputted to the model which had correlation with dolines.In this regards,306 dolines were identified by the photogrammetric Unmanned Aerial Vehicles(UAV)method in 600 hectares of Salderan lands and then,these data were divided into the training(70%)and testing(30%)data for modelling.The results of DSM modeling showed that classified probability of doline occurrences in the Saldaran mountain were as follow:16.5%of the area high to very high,72%in the class of low to very low,and 5%in the moderate class.Also,locally,in Saldaran mountain,the Pirghar aquifer has the highest potential for the doline development,followed by Bagh Rostam and Sarab aquifers.Also,the precipitation,digital elevation model,Topographic Position Index,drainage density,slope,TRASP(transformed the circular aspect to a radiation index),Snow-Covered Days and vegetation cover index are of highest importance in the DSM modeling,respectively.Accurate evaluation of the model using the Receiver Operating Characteristics(ROC)curve represents a very good accuracy(AUC=0.953)of the DSM model. 展开更多
关键词 Doline susceptibility mapping UAV photogrammetry Karst aquifers Generalized linear model(GLM) High Zagros Belt
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Analyzing the Impact of Climate Change on Maize Production to Develop Innovative Strategies for Ensuring Global Food Security
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作者 Farid Saber Nassar Ahmed Osman Abbas Mohamed Ezzat Elshekh 《Journal of Environmental & Earth Sciences》 2025年第2期198-210,共13页
This study examines the role of maize in food security and economic stability,focusing on its response to climate change and strategies to enhance resilience.Using a qualitative descriptive research methodology,the st... This study examines the role of maize in food security and economic stability,focusing on its response to climate change and strategies to enhance resilience.Using a qualitative descriptive research methodology,the study analyzes the impact of climate change on global maize production and proposes innovative strategies for sustainability and food security.The agricultural environment is vulnerable to heavy metal toxicity,which is linked to the relationship between soil health and climate change.From 1850 to 2020,the Earth’s temperature increased by 1.1℃,with projections indicating continued warming.This trend has significant economic implications,particularly in developing countries where agriculture employs 69%of the population.Heat waves and droughts represent abiotic stresses faced by maize.Research suggests that high greenhouse gas emissions could lead to a 24%reduction in maize yield by 2030.The study highlights the need to focus on breeding and phenotyping technologies to develop heat-and drought-tolerant maize varieties that use water efficiently.Additionally,strategies such as genomic editing,transcriptome analysis,and maize quality mapping are crucial to addressing these challenges.Developing insect-resistant maize is another objective.This study emphasizes the necessity of ongoing research to improve agricultural productivity and ensure food security,especially in light of global population growth.It also advocates for new regulations to reduce greenhouse gas emissions,which contribute to global warming. 展开更多
关键词 Abiotic Stresses Climate Change Food Security SUSTAINABILITY Zea mays
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Machine learning and remote sensing for modeling groundwater storage variability in semi-arid regions
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作者 Abdessamad Elmotawakkil Adil Moumane +1 位作者 Ali Ait Youssef Nourddine Enneya 《Intelligent Geoengineering》 2025年第3期151-163,共13页
This study investigates the prediction of groundwater Storage in the Rabat-Sale-Kenitra region under climate change conditions using advanced machine learning models.A comprehensive dataset encompassing hydrological,m... This study investigates the prediction of groundwater Storage in the Rabat-Sale-Kenitra region under climate change conditions using advanced machine learning models.A comprehensive dataset encompassing hydrological,meteorological,and geological factors was meticulously curated and preprocessed for model training.Six regression models Decision Tree,Random Forest,LightGBM,CatBoost,Extreme Learning Machine(ELM),and Artificial Neural Network(ANN)were employed to predict groundwater Storage,with hyperparameters optimized via grid search.The performance of these models was rigorously evaluated using metrics such as Root Mean Squared Error(RMSE),Mean Absolute Error(MAE),and the coefficient of determination(R^(2)).Results demonstrated that the LightGBM model outperformed the others,achieving an impressive testing RMSE of 3.07 and an R^(2)of 0.9997,indicating its robustness in handling large datasets.The Extreme Learning Machine and ANN showed considerable limitations,highlighting the importance of model selection.This research underscores the critical role of advanced machine learning techniques in enhancing groundwater resource management,providing valuable insights for policymakers in developing sustainable strategies to address groundwater challenges in the face of climate variability. 展开更多
关键词 Groundwater storage Machine learning PRECIPITATION TEMPERATURE Remote sensing
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Promoting sustainable mangrove tourism through payments for ecosystem services:Insights from Tongke-Tongke Village,South Sulawesi,Indonesia
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作者 Abdul MALIK Muhammad Ichsan ALI +2 位作者 Abdul Rasyid JALIL Abdul MANNAN Rahma MUSYAWARAH 《Regional Sustainability》 2025年第2期67-80,共14页
Mangrove ecosystems support biodiversity,protect coastal areas,and provide sustainable livelihoods.However,they face significant threats from deforestation and unsustainable land use practices.This study examines the ... Mangrove ecosystems support biodiversity,protect coastal areas,and provide sustainable livelihoods.However,they face significant threats from deforestation and unsustainable land use practices.This study examines the viability of the payments for ecosystem services(PES)programs in promoting sustainable mangrove tourism in Tongke-Tongke Village,Sinjai District,South SulawesiProvince,Indonesia.We collected data through household surveys,semi-structured stakeholder interviews,and tourist questionnaires to evaluate the economic value of mangrove tourism and tourists’willingness to pay(WTP)for conservation.Analytical methods included quantitative descriptive analysis,thematic analysis,travel cost analysis,and contingent valuationmethod.The results indicatedstrong community support,with 70.00% of respondents acknowledging sustainable mangrove tourism’s economic,environmental,and cultural benefits.Economic estimates revealedthat mangrove tourism generated 943.00 USD/(hm^(2)·a),while tourists’WTP for conservation rangedfrom 0.21 to 0.56 USD/(person×month),contributing approximately 11.39 USD/(hm^(2)·a).Despite challenges such as inadequate infrastructure,socioeconomic disparities,and land privatization,this study advocates for integrating the PES programs,enhancing governance frameworks,and fostering local community engagement to ensure equitable benefit distribution and maximize the potential of mangrove tourism.These strategies aim to bolster conservation efforts,improve local livelihoods,and strengthen the resilience of mangroveecosystems. 展开更多
关键词 Mangrove tourism Payments for ecosystem services(PES) Willingness to pay(WTP) Sustainable tourism South Sulawesi
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Erratum to:Flooding(or breaching)of inter-connected proglacial lakes by cascading overflow in the arid region of Western Mongolia(Mt.Tsambagarav,Mongolian Altai)
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作者 Otgonbayar DEMBEREL Chinmay DASH +6 位作者 Battsetseg DUGERSUREN Munkhbat BAYARMAA Yeong Bae SEONG Elora CHAKRABORTY Batsuren DORJSUREN Atul SINGH Nemekhbayar GANHUYAG 《Journal of Mountain Science》 2025年第5期1888-1888,共1页
The author affiliation and the funding information in the Acknowledgement section of the online version of the original article was revised.One affiliation(the 8th affiliation)of the first author is added.The Acknowle... The author affiliation and the funding information in the Acknowledgement section of the online version of the original article was revised.One affiliation(the 8th affiliation)of the first author is added.The Acknowledgement section of the original article has been revised to:Acknowledgments:This research was funded by the National University of Mongolia under grant agreement P2023(grant number P2023-4578)and supported by the Chey Institute for Advanced Studies“International Scholarship Exchange Fellowship for the academic year of 2024-2025”,Republic of Korea,and the National University of Mongolia.We would like to acknowledge the National University of Mongolia and Soumik Das from the Center for the Study of Regional Development,Jawaharlal Nehru University,New Delhi-110067,for his valuable assistance in preparing the geological maps. 展开更多
关键词 Mongolia proglacial lakes Mongolian Altai arid region tsambagarav cascading overflow geological maps FLOOD
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Climate Change’s Impact on Honeybee Distribution and Population,Habitats,Bioproducts,and Pest Threats as Protective of SDGs
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作者 Mohamed Ezzat Elshekh Saeed Mohammed Algarni +1 位作者 Ahmed Osman Abbas Farid Saber Nassar 《Journal of Environmental & Earth Sciences》 2025年第5期108-116,共9页
Bees are essential to human life and ecosystems,significantly contributing to medicine,economics,and environmental equilibrium.Bees serve an essential function as pollinators,facilitating the cultivation of various fr... Bees are essential to human life and ecosystems,significantly contributing to medicine,economics,and environmental equilibrium.Bees serve an essential function as pollinators,facilitating the cultivation of various fruits and vegetables.Bees contribute approximately 117 billion US dollars annually to the economy through their role in crop pollination.They have a direct impact on 35%of agricultural crops and 84%of cultivated plants.Bee products,including honey,propolis,and royal jelly,have been utilized in various traditional medicine practices across numerous countries.These substances have been utilized for their anti-inflammatory,antioxidant,and antibacterial properties.In addition to their economic,ecological,and medical significance,they serve as bioindicators for assessing the health of ecological systems by monitoring distribution and population dynamics.This offers important insights into the current situation,especially regarding the substantial impacts of climate change on the environment.This article seeks to synthesize data from various studies to examine the impact of climate change on bee populations and their habitats.This study illustrates the significant effects of future climate models for 2050 and 2070 on bee distribution,resulting in the decline of specific species populations. 展开更多
关键词 Bee Distribution Bee Population Climate Change Ecology Biodiversity
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Impacts of China food trade on global resource and environment:A sustainable development assessment
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作者 Xiang Wang Xin Li +3 位作者 Libang Ma Jing Bai Li Li Simin Yan 《Geography and Sustainability》 2025年第6期101-114,共14页
Meeting China's burgeoning food demand while safeguarding the resources and environmental long-term development is a critical challenge for the sustainable food systems of this century.China's accelerated food... Meeting China's burgeoning food demand while safeguarding the resources and environmental long-term development is a critical challenge for the sustainable food systems of this century.China's accelerated food imports have far-reaching implications for global resource allocation and environmental development.Hence,detailed information regarding China's food trade resource-environmental impacts is imperative for the design of effective policies that promote environmental mitigation and resource conservation.This study estimated the spatial transfers of virtual water trade(VWT),virtual land trade(VLT),and virtual GHG emission trade(VGT)embodied in China's food trade.Findings indicate that the VWT,VLT,and VGT transfers embodied in China's food trade increased by 10.4%,9.8%,and 15.2%annually.It is more important to mention that virtual water import(VWI)and virtual land import(VLI)saved 119.5×10~9m^(3)of global water resources and 29.5 Mha of land resources,respectively,but virtual GHG emission import(VGI)increased global 13 Mt CO_(2)-eq GHG emissions.The divergent impacts of China's food import on global food sustainability stem from variations in virtual water content,yields and emission intensities.Moreover,significant differences in sustainability scores were found among the top 15 importing countries,indicating that China's food trade contributes to the deepening of global food system sustainability.This study highlights the need for a multifaceted approach that considers the various environmental impacts of food trade.China is therefore encouraged to fully integrate the benefits of resource and environmental conservation into its sustainable food trade strategy,restructuring the food system to ensure the long-term nourishment of its large population. 展开更多
关键词 Food trade Virtual water Virtual land Virtual GHG emission Sustainable development assessment China
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Geomorphological development through periglacial landform changes and its contribution to soil diversity in Mount Ilgar in Northeastern Türkiye
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作者 DEDE Volkan DENGİZ Orhan +5 位作者 DEMİRAĞ TURAN İnci ŞENOL Hüseyin ZORLU Kuttusi SERİN Soner PACCİ Sena AY Abdurrahman 《Journal of Mountain Science》 2025年第11期3944-3963,共20页
Soil development may be impacted by periglacial processes that take place in regions where freezing and thawing episodes predominate.Mount Ilgar(2918 m a.s.l.)is a volcanic mass located on the Lesser Caucasus(4090 m a... Soil development may be impacted by periglacial processes that take place in regions where freezing and thawing episodes predominate.Mount Ilgar(2918 m a.s.l.)is a volcanic mass located on the Lesser Caucasus(4090 m a.s.l.).The objectives of this study were to assess how climate influenced the formation of periglacial landforms in Mount Ilgar,identify the morphological characteristics of each patterned ground by periglacial landforms,and investigate the pedological processes,physicochemical,biological,and mineralogical characteristics of the soils that developed on each of them.Non-sorted steps,mud circles,and stony earth circles are examples of periglacial landforms found on the slopes of the hills?küzkoku(2804 m a.s.l.)and Misikan(2674 m a.s.l.)to the north of Mount Ilgar.In terms of soil physical characteristics,the average aggregate stability and clay content of soils created on non-sorted steps are 43.52%and 8.9%,respectively;these values,however,rise dramatically in soils formed on mud circles and stony earth circles.Chemically,the soils generated on the mud and stony earth circles have lower pH values than the soils formed on the non-sorted steps,but they have higher levels of organic matter.The microbial biomass carbon and basal respiration values of the soils generated on mud circles and stony earth circles are high due to the low pH values and high organic matter contents of these soils,which also have an impact on biological activity.The rate at which soils weather is also influenced by variations in their physical,chemical,and biological characteristics.It is found that the quartz mineral is more prevalent in the soils developed on mud circles landforms,despite the fact that the distribution of the basic clay minerals in the soils is essentially the same.Additionally,smectite clay minerals with a 2:1 layer are present,according to clay mineral analysis,especially in soils that are produced from mud circle formations.One may argue that the influence of local microtopographic landforms on soil formations were the primary cause of the differences in soils on periglacial landforms developed on identical geological material and at similar elevations. 展开更多
关键词 Periglacial landforms Climate Soil formation Mount Ilgar Lesser Caucasus Türkiye
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Electricity Theft and Its Impact on Quality of Service in Lubumbashi,DR Congo
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作者 David Milambo Kasumba Guy Nkulu Wa Ngoie +3 位作者 Hyacinthe Tungadio Diambomba Matthieu Kayembe Wa Kayembe Flory Kiseya Tshikala Bonaventure Banza Wa Banza 《Energy Engineering》 2025年第6期2401-2416,共16页
Electricity theft significantly impacts the reliability and sustainability of electricity services,particularly in developing regions.However,the socio-economic,infrastructural,and institutional drivers of theft remai... Electricity theft significantly impacts the reliability and sustainability of electricity services,particularly in developing regions.However,the socio-economic,infrastructural,and institutional drivers of theft remain inadequately explored.Here we examine electricity theft in Lubumbashi,Democratic Republic of Congo,focusing on its patterns,causes,and impacts on service quality.Theft rates exceeded 75%in peripheral municipalities like Katuba and Kampemba,driven by poverty,weak law enforcement,and poor infrastructure dominated by above-ground networks.In contrast,central areas like Kamalondo and Lubumbashi reported lower theft rates due to better urban planning and underground systems.We found that electricity theft directly correlates with frequent voltage fluctuations,prolonged outages,and grid overloads.Socio-economic factors,including high connection fees and poverty,emerged as primary drivers,while institutional weaknesses such as corruption and ineffective enforcement perpetuate theft.Addressing theft requires a holistic approach integrating infrastructure modernization,socio-economic reforms,and institutional strengthening.Transitioning to underground networks,providing affordable electricity access,and adopting advanced metering systems are crucial.Overall,this study highlights the systemic nature of electricity theft and provides actionable insights for improving electricity service delivery and equity in urban settings. 展开更多
关键词 Electricity theft service quality infrastructure disparities socio-economic drivers Lubumbashi
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土耳其棉花堡与中国黄龙和白水台钙华退化原因对比研究 被引量:4
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作者 董发勤 代群威 +7 位作者 赵玉连 陈木兰 饶瀚云 吕珍珍 宗美荣 李博文 Emin Ciftci Mehmet Furkan Sener 《中国岩溶》 CAS CSCD 北大核心 2021年第6期1069-1076,共8页
通过比较中国四川黄龙、中国云南白水台、土耳其帕穆克卡莱棉花堡三地钙华景观的基本环境地质特征、钙华景观水化学、钙华沉积生物因素的差异性,探讨了土耳其棉花堡钙华退化缓慢的影响因素。对比发现,棉花堡景区藻类约为38种,种类单一,... 通过比较中国四川黄龙、中国云南白水台、土耳其帕穆克卡莱棉花堡三地钙华景观的基本环境地质特征、钙华景观水化学、钙华沉积生物因素的差异性,探讨了土耳其棉花堡钙华退化缓慢的影响因素。对比发现,棉花堡景区藻类约为38种,种类单一,植被覆盖率较低,沉积主要受物理化学因素控制,沉积速率较快,多形成较好的层状结构,杂质少,且原生孔隙度较低,结构致密,结晶度较高,不易坍塌损坏;黄龙和白水台景区藻类分别为86种、196种,种类多样,且植被覆盖率皆高达80%以上,沉积主控于化学和生物因素,沉积速率较慢,结构呈多孔疏松状或多孔珊瑚状,原生孔隙度普遍较高,易退化。此外,棉花堡钙华景区泉水各离子含量均高于黄龙和白水台景区,尤其是Ca2+和HCO3,这能有效促进CaCO3的沉积。 展开更多
关键词 土耳其棉花堡 钙华 退化 微生物
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Evaluating effectiveness of frequency ratio, fuzzy logic and logistic regression models in assessing landslide susceptibility: a case from Rudraprayag district, India 被引量:8
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作者 Mehebub SAHANA Haroon SAJJAD 《Journal of Mountain Science》 SCIE CSCD 2017年第11期2150-2167,共18页
Rudraprayag in Garhwal Himalayan division is one of the most vulnerable districts to landslides in India. Heavy rainfall, steep slope and developmental activities are important factors for the occurrence of landslides... Rudraprayag in Garhwal Himalayan division is one of the most vulnerable districts to landslides in India. Heavy rainfall, steep slope and developmental activities are important factors for the occurrence of landslides in the district. Therefore, specific assessment of landslide susceptibility and its accuracy at regional level is essential for disaster management and proper land use planning. The article evaluates effectiveness of frequency ratio, fuzzy logic and logistic regression models for assessing landslide susceptibility in Rudraprayag district of Uttarakhand state, India. A landslide inventory map was prepared and verified by field data. Fourteen landslide parameters and generated inventory map were utilized to prepare landslide susceptibility maps through frequency ratio, fuzzy logic and logistic regression models. Landslide susceptibility maps generated through these models were classified into very high, high, medium, low and very low categories using natural breaks classification. Receiver operating characteristics(ROC) curve, spatially agreed area approach and seed cell area index(SCAI) method were used to validate the landslide models. Validation results revealed that fuzzy logic model was found to be more effective in assessing landslide susceptibility in the study area. The landslide susceptibility map generated through fuzzy logic model can be best utilized for landslide disaster management and effective land use planning. 展开更多
关键词 LANDSLIDE SUSCEPTIBILITY Frequency ratio LOGISTIC regression Natural BREAKS classification Remote sensing GEOGRAPHIC information system
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Recommending the IHACRES model for water resources assessment and resolving water conflicts in Africa 被引量:7
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作者 Samir Mohammad Ali Alredaisy 《Journal of Arid Land》 SCIE 2011年第1期40-48,共9页
The International Association of Hydrological Sciences (IAHS) recognized the lack of hydro- logical data as a world-wide problem in 2002 and adopted the Prediction of Ungauged Basins (PUB) as a decadal research ag... The International Association of Hydrological Sciences (IAHS) recognized the lack of hydro- logical data as a world-wide problem in 2002 and adopted the Prediction of Ungauged Basins (PUB) as a decadal research agenda during the period of 2003 to 2012. One of the objectives is to further develop methodologies for prediction in ungauged basins and to reduce uncertainties in model prediction. Estimation of stream flows is required for flood control, water quality control, valley habitat assessment and water budget of a country. However, the majority of water catchments, streams and valleys are ungauged in most developing countries. The main objective of this paper is to introduce the IHACRES (Identification of Hy- drographs and Components from Rainfall, Evaporation and Stream) model into African hydrological plan- ning as a methodology for water resources assessment, which in turn can be used to resolve water conflicts between communities and countries and to study the climate change issues. This is because the IHACRES model is applied for the estimation of flows in ungauged catchments whose physical catchments descriptors (PCDs) can be determined by driving variables (i.e. rainfall and temperature); and also in gauged streams but whose gauging stations are no longer operational but historical data are available for model calibration. The model provides a valuable insight into the hydrologic behaviour of the upper water sources for valleys as well as provides a useful methodology for water resources assessment in situations of scarce financial resources in developing countries. In addition, it requires relatively few parameters in its calibration and has been successful applied in previous regionalization studies. It will also make possible the equitable distri- bution of water resources in international basins and rivers' catchments. This paper does not apply the model anywhere, but recommends it as a methodology for water resources assessment in order to cure water conflicts on the African continent. 展开更多
关键词 ungauged catchment water resources assessment RAINFALL RUNOFF lumped models Nile Basin AFRICA
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How Chinese Financial Centers Integrate into Global Financial Center Networks:An Empirical Study Based on Overseas Expansion of Chinese Financial Service Firms 被引量:19
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作者 PAN Fenghua HE Ziyun +2 位作者 Thomas SIGLER Kirsten MARTINUS Ben DERUDDER 《Chinese Geographical Science》 SCIE CSCD 2018年第2期217-230,共14页
The increasing globalization of the Chinese economy has been enabled by both Chinese financial institutions operating globally as well as international firms operating within China. In geographical terms, this has bee... The increasing globalization of the Chinese economy has been enabled by both Chinese financial institutions operating globally as well as international firms operating within China. In geographical terms, this has been organized through a number of strategic cities serving as gateways for the exchange of financial functions, products and practices between China and the global economy. Drawing on location data of financial service firms in China listed on stock exchanges in Shenzhen, Shanghai and Hong Kong, this paper shows that Chinese financial firms are expanding globally and how Chinese financial centers are positioned and connected in the urban networks shaped by these financial service firms. It is found that Hong Kong, China, holds strategic positions in the integration of Chinese cities into global financial center networks, and that establishing a foothold in global financial centers such as New York and London has been a priority for Chinese financial institutions. The increasing capital flows directed by Chinese financial institutionssuggests a shifting global financial geography, with numerous Chinese cities playing increasingly important roles within global financial center networks. 展开更多
关键词 urban networks corporate networks financial service firms global financial centers China
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Spatial Estimation of Soil Erosion Risk Using RUSLE Approach, RS, and GIS Techniques: A Case Study of Kufranja Watershed, Northern Jordan 被引量:8
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作者 Yahya Farhan Dalal Zregat Ibrahim Farhan 《Journal of Water Resource and Protection》 2013年第12期1247-1261,共15页
Wadi Kufranja catchment (126.3 km2), northern Jordan, was selected to estimate annual soil loss using the Revised Universal Soil Loss Equation (RUSLE), remote sensing (RS), and geographic information system (GIS). RUS... Wadi Kufranja catchment (126.3 km2), northern Jordan, was selected to estimate annual soil loss using the Revised Universal Soil Loss Equation (RUSLE), remote sensing (RS), and geographic information system (GIS). RUSLE factors (R, K, LS, C and P) were computed and presented by raster layers in a GIS environment, then multiplied together to predict soil erosion rates, and to generate soil erosion risk categories and soil erosion severity maps. The estimated potential average annual soil loss is 10 ton·ha-1·year-1 for the catchment, and the potential erosion rates from recognized erosion classes ranged from 0.0 to 1850 ton·ha-1·year-1. About 42.1% (5317.23 ha) of the catchment area was predicted to have moderate risk of erosion, with soil loss between 5 - 25 ton·ha-1·year-1. Risk of erosion is severe to extreme over 31.2% (3940.56 ha) of the catchment, where calculated soil loss is 25 - 50 and >50 ton·ha-1·year-1. Apart from the gentle slopes of the alluvial fan (Krayma town and surroundings), the lower and the middle reaches of the watershed suffer from severe to extreme erosion risk. High terrain, slope steepness, removal of vegetation, and poor conservation practices are the most prominent causes of soil erosion. 展开更多
关键词 JORDAN SOIL Erosion Risk Mapping SEVERITY RUSLE WADI Kufranja
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Analysing the relationship between drought and soil erosion using vegetation health index and RUSLE models in Godavari middle sub-basin,India 被引量:8
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作者 Md Masroor Haroon Sajjad +5 位作者 Sufia Rehman Roshani Singh Md Hibjur Rahaman Mehebub Sahana Raihan Ahmed Ram Avtar 《Geoscience Frontiers》 SCIE CAS CSCD 2022年第2期21-33,共13页
Drought is a natural phenomenon posing severe implications for soil,groundwater and agricultural yield.It has been recognized as one of the most pervasive global change drivers to affect the soil.Soil being a weakly r... Drought is a natural phenomenon posing severe implications for soil,groundwater and agricultural yield.It has been recognized as one of the most pervasive global change drivers to affect the soil.Soil being a weakly renewable resource takes a long time to form,but it takes no time to degrade.However,the response of soil to drought conditions as soil loss is not manifested in the existing literature.Thus,this study makes a concerted effort to analyze the relationship between drought conditions and soil erosion in the middle sub-basin of the Godavari River in India.MODIS remote sensing data was utilized for driving drought indices during 2000-2019.Firstly,we constricted Temperature condition index(TCI)and Vegetation Condition Index(VCI)from Land Surface Temperature(LST)and Enhanced Vegetation Index(EVI)derived from MODIS data.TCI and VCI were then integrated to determine the Vegetation Health Index(VHI).Revised Universal Soil Loss Equation(RUSLE)was utilized for estimating soil loss.The relationship between drought condition and vegetation was ascertained using the Pearson correlation.Most of the northern and southern watersheds experienced severe drought condition in the sub-basin during2000-2019.The mean frequency of the drought occurrence was 7.95 months.The average soil erosion in the sub-basin was estimated to be 9.88 t ha^(-1)year^(-1).A positive relationship was observed between drought indices and soil erosion values(r value being 0.35).However,wide variations were observed in the distribution of spatial correlation.Among various factors,the slope length and steepness were found to be the main drivers of soil erosion in the sub-basin.Thus,the study calls for policy measures to lessen the impact of drought and soil erosion. 展开更多
关键词 Drought vulnerability Soil erosion RUSLE Vegetation Health Index(VHI) Godavari middle sub-basin
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Assessment of Human Impacts on Vegetation in Built-up Areas in China Based on AVHRR,MODIS and DMSP_OLS Nighttime Light Data,1992–2010 被引量:5
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作者 LIU Qinping YANG Yongchun +2 位作者 TIAN Hongzhen ZHANG Bo GU Lei 《Chinese Geographical Science》 SCIE CSCD 2014年第2期231-244,共14页
Since the reform and opening-up program started in 1978,the level of urbanization has increased rapidly in China.Rapid urban expansion and restructuring have had significant impacts on the ecological environment espec... Since the reform and opening-up program started in 1978,the level of urbanization has increased rapidly in China.Rapid urban expansion and restructuring have had significant impacts on the ecological environment especially within built-up areas.In this study,ArcGIS 10,ENVI 4.5,and Visual FoxPro 6.0 were used to analyze the human impacts on vegetation in the built-up areas of 656Chinese cities from 1992 to 2010.Firstly,an existing algorithm was refined to extract the boundaries of the built-up areas based on the Defense Meteorological Satellite Program Operational Linescan System(DMSP_OLS)nighttime light data.This improved algorithm has the advantages of high accuracy and speed.Secondly,a mathematical model(Human impacts(HI))was constructed to measure the impacts of human factors on vegetation during rapid urbanization based on Advanced Very High Resolution Radiometer(AVHRR)Normalized Difference Vegetation Index(NDVI)and Moderate Resolution Imaging Spectroradiometer(MODIS)NDVI.HI values greater than zero indicate relatively beneficial effects while values less than zero indicate proportionally adverse effects.The results were analyzed from four aspects:the size of cities(metropolises,large cities,medium-sized cities,and small cities),large regions(the eastern,central,western,and northeastern China),administrative divisions of China(provinces,autonomous regions,and municipalities)and vegetation zones(humid and semi-humid forest zone,semi-arid steppe zone,and arid desert zone).Finally,we discussed how human factors impacted on vegetation changes in the built-up areas.We found that urban planning policies and developmental stages impacted on vegetation changes in the built-up areas.The negative human impacts followed an inverted′U′shape,first rising and then falling with increase of urban scales.China′s national policies,social and economic development affected vegetation changes in the built-up areas.The findings can provide a scientific basis for municipal planning departments,a decision-making reference for government,and scientific guidance for sustainable development in China. 展开更多
关键词 vegetation change human impact urbanization built-up areas nighttime light data Normalized Difference Vegetation Index(NDVI)
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Command and Control Cities in Global Space-economy Before and after 2008 Geo-economic Transition 被引量:5
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作者 Ernest Ka Shing LEE Simon Xiaobin ZHAO Yang XIE 《Chinese Geographical Science》 SCIE CSCD 2012年第3期334-342,共9页
The global economic downturn caused primarily by the US sub-prime mortgage crisis in 2007 engendered revenue loss of the multinational corporations. Existing studies have yet to depict the detrimental impacts on city... The global economic downturn caused primarily by the US sub-prime mortgage crisis in 2007 engendered revenue loss of the multinational corporations. Existing studies have yet to depict the detrimental impacts on city's command and control functions induced by the sub-prime mortgage crisis together with its residual wave of global economic recession on the global spatial economy. Recent and previous studies have produced an 'instant history' of the global spatial economy before the global economic downturn undermines the global economy in late 2008. How- ever, the waxes and wanes of major cities' command and control functions on the global economic arena before and after the outbreak of financial crisis and its associated geo-economic transitions are still poorly understood. This paper attempts to contribute a new set of customized data to update and fill in the gap in the literature with the investigation of the command and control functions of cities arotmd the world from 2005 to 2009. Particular attentions are paid to the time-space relationship of the geo-economic transition that can capture the recent historical images of the com- mand and control situation of different cities in the world. 展开更多
关键词 global space-economy command and control cities geo-economic transition China
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