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Tracing suspended and bed sediments during high and low water periods using geochemical characteristics-Case study:Vazrood watershed,northern Iran

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Journal of Mountain Science 2024年第2期21卷 470-483页

作者： KARIMI Nabiyeh GHOLAMI Leila KAVIAN Ataollah KHALEDI DARVISHAN Abdulvahed Department of Watershed management Faculty of Natural ResourcesSari Agricultural Sciences and Natural Resources UniversitySari ***Iran Department of Watershed management Engineering Faculty of Natural ResourcesTarbiat Modares UniversityNoor ***Iran

Complete and comprehensive information about sediment dynamic and identification of hotspots of sediment production and transport are necessary for understanding the erosion processes and increasing the efficiency of soil and water conservation *** studies used the sediment fingerprint techniques to investigate the contribution of different sources in suspended and bed sediment yield of the ***,the contribution of various land use/land covers in suspended and bed sediment yield for the great Caspian Sea basin is in an aura of ambiguity and the present study was conducted to gather information about an important part of this area in northern Iran,where rangelands are located upstream of Hyrcanian forests and dense agricultural lands are located *** surface soil of different land use/land covers including forest,rangeland,agriculture and streambank lands were sampled in 30 *** and bed sediments were sampled in the watershed outlet in two high and low water *** characteristics of soil and sediment samples containing 59 elements were measured using ICP-OES GBC *** reliable and suitable tracers from 59 elements were then selected using Range test,Kruskal-Wallis and Discriminant Function Analysis,respectively,in FingerPro package of R *** results showed that for suspended sediment,streambank and rangeland had the highest contributions of 86.2%and 47.5%,respectively,in two high and low water *** bed sediment,in two high and low water periods,rangeland and streambank had the highest contributions of 73.8%and 84.4%,*** use change and especially human activities such as agriculture,road construction and development of residential areas along the main river riparian zone has led to a significant increase in suspended and bed sediments.

关键词： Caspian Sea basin FingerPro Geochemistry Sediment transport Tracer combination

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Parkland trees on smallholder farms ameliorate soil physical-chemical properties in the semi-arid area of Tigray,Ethiopia

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Journal of Arid Land 2024年第1期16卷 1-13页

作者： Selam LJALEM Emiru BIRHANE Kassa TEKA Daniel H BERHE Department of Land resources management and Environmental Protection College of Dryland Agriculture and Natural ResourcesMekelle UniversityMekelle 231Ethiopia Institute of Climate and Society Mekelle UniversityMekelle 231Ethiopia faculty of Environmental Sciences and natural Resource management Norwegian University of Life Sciences(NMBU)Ås 1432Norway Department of natural resources management Adigrat UniversityAdigrat 50Ethiopia

Proposed agroforestry options should begin with the species that farmers are most familiar with,which would be the native multipurpose trees that have evolved under smallholder farms and socioeconomic *** African birch(Anogeissus leiocarpa(DC.)Guill.&Perr.)and pink jacaranda(Stereospermum kunthianum Cham.)trees are the dominant species in the agroforestry parkland system in the drylands of Tigray,*** farmers highly value these trees for their multifunctional uses including timber,firewood,charcoal,medicine,*** trees also could improve soil ***,the amount of soil physical and chemical properties enhanced by the two species must be determined to maintain the sustainable conservation of the species in the parklands and to scale up to similar agroecological ***,we selected twelve isolated trees,six from each species that had similar dendrometric characteristics and were growing in similar environmental *** divided the canopy cover of each tree into three radial distances:mid-canopy,canopy edge,and canopy gap(control).At each distance,we took soil samples from three different *** collected 216 soil samples(half disturbed and the other half undisturbed)from each canopy position and soil *** density(BD),soil moisture content(SMC),soil organic carbon(SOC),total nitrogen(TN),available phosphorus(AP),available potassium(AK),p H,electrical conductivity(EC),and cation exchange capacity(CEC)were *** revealed that soil physical and chemical properties significantly improved except for soil texture and EC under both species,CEC under ***,and soil p H under ***,all the studied soils were improved under both species canopy as compared with canopy ***,TN,AP,and AK under canopy of these trees were respectively 24.1%,11.1%,55.0%,and 9.3% higher than those soils under *** two parkland agroforestry species significantly enhanced soil fertility near the canopy of top

关键词： agroforestry bulk density carbon stock dispersed tree soil texture tree canopy

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Annual growth of Fagus orientalis is limited by spring drought conditions in Iran’s Golestan Province

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Journal of Forestry Research 2024年第1期35卷 128-142页

作者： Khalil Ghorbani Jahangir Mohammadi Laleh Rezaei Ghaleh Department of Water Engineering Faculty of Water and Soil EngineeringGorgan University of Agricultural Sciences and Natural ResourcesGorganIran Department of Forestry Gorgan University of Agricultural Sciences and Natural ResourcesGorganIran Department of Water Engineering Faculty of AgricultureUrmia UniversityUrmiaIran

Due to the lack of a uniform and accurate defi-nition of‘drought’,several indicators have been introduced based on different variables and methods,and the efficiency of each of these is determined according to their relationship with *** relationship between two drought indices,SPI(standardized precipitation index)and SPEI(standard-ized precipitation-evapotranspiration index)in different sea-sons was investigated using annual rings of 15 tree samples to determine the effect of drought on the growth of oriental beech(Fagus orientalis Lipsky)in the Hyrcanian forests of northern *** different evapotranspiration calcula-tion methods were evaluated on SPEI efficiency based on Hargreaves-Samani,Thornthwaite,and Penman-Monteith methods using the step-by-step M5 decision tree regression *** results show that SPEI based on the Penman-Monteith in a three-month time scale(spring)had similar temporal changes and a better relationship with annual tree rings(R^(2)=0.81)at a 0.05 significant *** change and a decreasing trend in the time series of annual tree rings are similar to the variation in the SPEI based on the Penman-Monteith *** affecting evapotranspiration,temperature,wind speed,and sunshine hours(used in the Penman-Monteith method),increased but precipitation *** non-linear modeling methods,SPEI based on Penman-Monteith best illustrated climate changes affecting tree growth.

关键词： Climate change Drought index Hyrcanian forests SPEI'Annual growth rings Fagus orientalis

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Depositional Responses to the Mongol-Okhotsk Ocean Closure in the Central Area of the Great Xing’an Range: Insights into Thrust Faults and Foreland Basins

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Journal of Earth Science 2024年第3期35卷 797-811页

作者： Zheren Zhao Shichao Li Lingyu Zhang College of Earth Sciences Jilin UniversityChangchun 130061China Key Laboratory of Mineral resources Evaluation in Northeast Asia Ministry of Natural ResourcesChangchun 130061China Department of Geosciences and natural Resource management University of CopenhagenCopenhagen 1350Denmark

The Mongol-Okhotsk Ocean,which has been closing gradually from the west to the east beginning since the Late Paleozoic,was an important part of the Central Asian Orogenic *** influenced the tectonic framework of Northeast Asia in the Mesozoic,especially the Late Mesozoic arc-basin system that is widely distributed in the Great Xing’an ***,the manner in which the Mongol-Okhotsk Ocean affected the sedimentary basin development remains poorly *** address this issue,we conducted U-Pb dating of detrital zircon deposited sedimentary basins of the central Great Xing’an *** examining the possible provenances of the detrital zircon and the structural controls of the basins,we found that a key sedimentary unit was deposited around Late Jurassic-Early *** provenance was a felsic source in a back-arc setting of an active continental *** findings also suggest the existence of a unified geodynamic setting that affected the coeval development of basins in the northern Great Xing’an Range and the Yanshan fold-thrust belt along the northern margin of North China *** research helps to better understand the complex tectonic processes which shaped the Northeast Asia during the Late Mesozoic.

关键词： Mongol-Okhotsk tectonic domain depositional responses Murui Formation zircon geochemistry tectonics.

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Participatory Risk Governance for Seoul, South Korea's Flood Risk management

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International Journal of Disaster Risk Science 2024年第03期15卷 317-331页

作者： Bokjin Ro Gregg Garfin School of Geography Development and Environment The University of Arizona Interdisciplinary Program for Disaster Crisis and Risk Management Sungkyunkwan University School of natural resources and the Environment The University of Arizona

Risk governance is a widely used framework in natural and societal risk management research. Risks from natural hazards in urban areas call for the establishment of rigorous and participatory urban risk governance. In this study, we examined participatory risk governance(PRG) of flood risk management(FRM) in Seoul, South Korea. We conducted key informant interviews and implemented a survey with citizens, to explore perceptions of flood risks and risk management, and to examine prospects for improving PRG in Seoul. We found a gap between the perceptions of key informants and *** informants believed that citizens' low awareness of flood risks hinders PRG. Yet our research found that citizens' risk awareness was not low, and risk awareness may not be the main barrier to participation in PRG. Instead, we found that citizens lacked knowledge of FRM actions, and they assigned government bodies a high level of responsibility for FRM,compared to the level of responsibility that citizens assigned to themselves. Moreover, the actors involved in FRM tended not to trust each other, which implies a lack of mutual understanding. To increase the eff ectiveness of PRG, we suggest a polycentric governance structure anchored by a leading actor group, and active promotion of the participation of actors at multiple levels of governance. Communication between government and citizen participants, designed to foster improved understanding and recognition of one another's roles and contributions to FRM, will enhance trust and improve the implementation of PRG in Seoul.

关键词： Citizen participation Flood risk management Participatory risk governance Risk awareness South Korea Urban flood risk

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Analysis of the inflection points of height-diameter models

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Forest Ecosystems 2024年第4期11卷 414-422页

作者： Tzeng Yih Lam Mark J.Ducey Department of Forest resources management Faculty of ForestryThe University of British Columbia2045-2424 Main MallVancouverBCV6T 1Z4 Canada Department of natural resources and the Environment University of New Hampshire114 James HallDurhamNH 03824USA

The inflection point is an important feature of sigmoidal height-diameter(H-D)*** is often cited as one of the properties favoring sigmoidal model ***,there are very few studies analyzing the inflection points of H-D *** goals of this study were to theoretically and empirically examine the behaviors of inflection points of six common H-D models with a regional *** six models were the Wykoff(WYK),Schumacher(SCH),Curtis(CUR),HossfeldⅣ(HOS),von Bertalanffy-Richards(VBR),and Gompertz(GPZ)*** models were first fitted in their base forms with tree species as random effects and were then expanded to include functional traits and spatial *** distributions of the estimated inflection points were similar between the two-parameter models WYK,SCH,and CUR,but were different between the threeparameter models HOS,VBR,and *** produced some of the largest inflection *** and VBR produced concave H-D curves without inflection points for 12.7%and 39.7%of the tree *** species or decreasing shade tolerance resulted in larger inflection *** trends in the estimated inflection points of HOS and VBR were entirely opposite across the ***,HOS could produce concave H-D curves for portions of the *** on the studied behaviors,the choice between two-parameter models may not *** recommend comparing seve ral three-parameter model forms for consistency in estimated inflection points before deciding on *** sigmoidal models to have inflection points does not necessarily mean that they will produce fitted curves with *** study highlights the need to integrate analysis of inflection points into modeling H-D relationships.

关键词： Concavity Forest inventory and analysis Generalized height-diameter models Growth functions Height-diameter functions Mixed-effects modeling Points of inflection Species-specific models

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Comprehensive Risk Assessment of Sea Level Rise and Tropical Cyclones in Dongzhaigang Mangroves,China

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Chinese Geographical Science 2024年第4期34卷 631-646页

作者： DING Ruyi CAI Rongshuo YAN Xiuhua LI Cuihua WANG Cui NIE Xinyu Third Institute of Oceanography Ministry of Natural ResourcesXiamen 361005China

Mangroves play a pivotal role in tropical and subtropical coastal ecosystem,yet they are highly vulnerable to the effects of climate change,particularly the accelerated global sea level rise(SLR)and stronger tropical cyclones(TCs).However,there is a lack of research addressing future simultaneous combined impacts of the slow-onset of SLR and rapid-onset of TCs on China's *** order to develop a comprehensive risk assessment method considering the superimposed effects of these two factors and analyze risk for mangroves in Dongzhaigang,Hainan Island,China,we used observational and climate model data to assess the risks to mangroves under low,intermediate,and very high greenhouse gas(GHG)emission scenarios(such as SSP1-2.6,SSP2-4.5,and SSP5-8.5)in 2030,2050,and 2100,and compiled a risk assessment scheme for mangroves in Dongzhaigang,*** results showed that the combined risks from SLR and TCs will continue to rise;however,SLRs will increase in intensity,and TCs will *** comprehensive risk of the Dongzhaigang mangroves posed by climate change will remain low under SSP1-2.6 and SSP2-4.5 scenarios by 2030,but it will increase substantially by *** under SSP5-8.5 scenario,the risks to mangroves in Dongzhaigang are projected to increase considerably by 2050,and approximately 68.8%of mangroves will be at very high risk by *** risk to the Dongzhaigang mangroves is not only influenced by the hazards but also closely linked to their exposure and *** therefore propose climate resilience developmental responses for mangroves to address the effects of climate *** study for the combined impact of TCs and SLR on mangroves in Dongzhaigang,China can enrich the method system of mangrove risk assessment and provide references for scientific management.

关键词： mangrove climate change risk assessment combined hazards sea level rise(SLR) tropical cyclones(TCs) resilience development Dongzhaigang China

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Assessment of SoilGrids data for soil erosion estimation at watershed scale: A case study in northern Thailand

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Pedosphere 2024年第4期34卷 797-813页

作者： Chike Onyeka MADUEKE Dhruba Pikha SHRESTHA Panagiotis NYKTAS Department of natural resources Faculty of Geo-information Science and Earth Observation(ITC)University of TwenteEnschede 7500 AEthe Netherlands Department of Applied Earth Sciences Faculty of Geo-information Science and Earth Observation(ITC)University of TwenteEnschede 7500 AEthe Netherlands Department of Soil Science and Land resources management Nnamdi Azikiwe UniversityP.M.B.5025AwkaAnambra State 420110Nigeria

Soil erosion has been identified as one of the most destructive forms of land degradation,posing a threat to the sustainability of global economic,social and environmental *** underscores the need for sustainable land management that takes erosion control and prevention into *** requires the use of state-of-the-art erosion prediction *** models often require extensive input of detailed spatial and temporal data,some of which are not readily available in many developing countries,particularly detailed soil *** soil dataset Global Gridded Soil Information(SoilGrids)could potentially fill the data ***,its value and accuracy for soil erosion modelling in the humid tropics is still unknown,necessitating the need to assess its value vis-à-vis field-based *** major objective of this study was to conduct a comparative assessment of the value of SoilGrids and field-based soil data for estimating soil *** samples were collected from five physiographic positions(summit,shoulder,back slope,foot slope,and toe slope)using the soil catena *** were collected using a 5-cm steel sample ring(undisturbed)and a spade(disturbed).Data of the landform,predominant vegetation types,canopy cover,average plant height,land use,soil depth,shear strength,and soil color were recorded for each *** soil samples were subjected to laboratory analysis for saturated hydraulic conductivity,bulk density,particle size distribution,and organic matter *** functions were applied on the SoilGrids and field-based data to generate soil hydrological *** resultant field-based data were compared with the SoilGrids data for corresponding points/areas to determine the potential similarities of the two *** datasets were then used as inputs for soil erosion assessment using the revised Morgan-Morgan-Finney *** results from both datasets were again compared to determine the degree of *** r

关键词： hillslope modelling pedotransfer function similarity assessment soil erosion modelling soil loss soil survey

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Can Industrial Structure Upgrading Restrain Industrial Land Expansion?Evidence from China

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Chinese Geographical Science 2024年第3期34卷 504-518页

作者： CHEN Wei LI Qiao ZHANG Sun ZHOU Xue College of Economics and management Northwest A&F UniversityYangling Shaanxi 712100China Institute of Geographic Sciences&natural resources Research Chinese Academy of SciencesBeijing 100101China

China has made great achievements in industrial development and is transforming into a powerful manufacturing ***,the industrial land scale is also ***,whether industrial structure upgrading achieves the purpose of restraining industrial land expansion remains *** calculating the industrial land structure index(ILSI)and industrial land expansion scale(ILES),this study analyzed their temporal and spatial distribution characteristics at both regional and city levels from 2007to 2020 in *** show that industrial land expansion presents a different trend in the four regions,the ILES in the eastern region is the largest,and the speed of industrial land expansion has declined since 2013,but it has gradually increased since *** ILSI of the eastern and central regions is higher than that of the western and northeastern ***,a spatial Durbin model(SDM)has been established to estimate the spatial effect of industrial structure upgrading on industrial land expansion from 2007 ***,industrial structure upgrading has not slowed industrial land *** eastern and western regions require a greater amount of industrial land while upgrading the industrial *** improvement of the infrastructure level and international trade level has promoted industrial land expansion.

关键词： industrial development industrial structure upgrading industrial land expansion regional differences China

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Extract lithium from clay-type lithium ore by mixed acid and its mechanism Author links open overlay panel

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Particuology 2024年第8期91卷 323-332页

作者： Wuchang Zhou Ruiqi Xie Xiong Tong Xian Xie Yang Liu Zhihui Zhao faculty of Land Resource Engineering Kunming University of Science and TechnologyKunming650093China Technology Innovation Center for Comprehensive Utilization of Strategic Mineral resources Ministry of Natural ResourcesChengdu610041China National&Regional Engineering Research Center for Green comprehensive Utilization of Tailing resources from Metal Minerals Kunming650093China

A roasting-leaching test was carried out for the efficient utilization of clay-type lithium ore in the central region of Yunnan *** test used the mixed acid of sulfuric acid and phosphoric acid as the leaching *** the conditions of roasting temperature of 600℃,roasting time of 1 h,liquid-solid ratio of 5:1,volume ratio of H_(2)SO_(4)solution to H_(3)PO_(4)solution of 45:5,leaching time of 2 h and leaching temperature of 80℃,the leaching rate of lithium was as high as 97.83%.The leaching mechanism was studied by SEM,pore property analysis,XRD and *** was found that the morphology of the ore changed obviously after roasting and leaching,and a certain degree of collapse and fragmentation occurred,which provided favorable spatial conditions for the leaching of *** porosity,total intrusion volume and total pore area also increased after roasting and leaching,thus promoting the leaching of Li^(+).The results showed that chemical reaction taken placed during the roasting and *** phase of the sample changed from chlorite,kaolinite and diaspore(boehmite)mainly to corundum,hematite,periclase and quartz after ***,after leaching,no new phase was produced in the ore sample,and no S and P elements were found on the surface of the ore sample,indicating that the leaching mechanism of lithium might be the ion exchange between H^(+)and Li^(+).

关键词： Clay-type lithium ore Lithium extraction Roasting Leaching

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