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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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Effect of storm pattern on soil erosion in damaged rangeland;field rainfall simulation approach

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Journal of Mountain Science 2021年第3期18卷 706-715页

作者： leila gholami Abdulavahed KHALEDI DARVISHAN Veliber SPALEVIC Artemi CERDà Ataollah KAVIAN Department of Watershed Management Faculty of Natural ResourcesSari Agricultural Sciences and Natural Resources University(SANRU)Sari 48181-66996Iran Department of Watershed Management Engineering Faculty of Natural ResourcesTarbiat Modares UniversityNoor 46417-76489Iran Department of Geography Faculty of Philosophy of the University of MontenegroNiksic 81400Montenegro Soil Erosion and Degradation Research Group Departament de Geografia.Universitat de València.Blasco Ibà?ez 28 Valencia 46010Spain

Raindrop size,rainfall intensity and runoff discharge affect the detachment and transportation of soil *** these three factors,the rainfall intensity seems to be more important because it can change other two *** patterns can be determined by changing the rainfall intensity during the ***,the objective of this research is to test the influence of storm pattern on runoff,soil erosion and sediment concentration on a rangeland soil slope under field rainfall *** storm rainfall intensity patterns were selected for examining the effects of variations in storm event characteristics on soil erosion *** selected storm patterns were:I(45,55 and 70 mm h-1);II(45,70 and 55 mm h-1);III:(70,55 and 45 mm h-1);and IV(55,45 and 70 mm h1).The last pattern is a new one instead of the uniform pattern which has been sufficiently studied in previous *** experiments were conducted in field plots(in Kojour watershed,Mazandaran Province,Iran)with an area of one square meter and an constant slope gradient of 18%,surrounded by galvanised *** the nonuniform prioritization of the storm patterns for the studied variables,time to runoff(I>II>IV>III),runoff volume(III>IV>II>I),sediment concentration(IV>III>I>II)and soil erosion(III>IV>II>I)),it can be generally inferred that each pattern has specific effect on soil erosion processes during a *** results of the general linear model(GLM)test indicated that the effects of storm pattern on time to runoff,total runoff volume,runoff coefficient and soil erosion were significant at a level of 99%.The Duncan test showed that the storm patterns can be divided into three groups of III,IV;II;I(for time to runoff),I,II;IV,III(for runoff coefficient),and I;II;IV,III(for runoff volume and soil erosion).

关键词： Plot scale Runoff coefficient Soil erosion Storm patterns Time to runoff

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Effects of type, level and time of sand and gravel mining on particle size distributions of suspended sediment

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International Soil and Water Conservation Research 2018年第2期6卷 184-193页

作者： Seyed Hamidreza Sadeghi Sudabeh Gharemahmudli Hossein Kheirfam Abdulvahed Khaledi Darvishan Mahboobeh Kiani Harchegani Pari Saeidi leila gholami Mehdi Vafakhah Department of Watershed Management Engineering Faculty of Natural ResourcesTarbiat Modares UniversityNoor***Mazandaran ProvinceIran Department of Environmental Sciences Urmia Lake Research InstituteUrmia UniversityUrmiaIran Department of Watershed Management Engineering Faculty of Natural ResourcesTarbiat Modares UniversityNoor46417-76489Iran Department of Range and Watershed Management Sari Agriculture and Natural Resources UniversitySariMazandaran ProvinceIran

Monitoring the sediment transport behavior induced by different interventions, particularly sand mining from rivers, is needed to adaptively manage the watersheds. The particle size distribution of the sus-pended sediment in up and downstream of rivers is one of the main indicators to know about fate of sediments, which may be varied in different conditions. We investigated the effect of some types of sand and gravel (i.e., manual and low, semi-heavy, and heavy machinery) mining on particle size distribution of suspended sediment in the Vaz-e-Owlya, Vaz-e-Sofla and Alesh-Roud riverine mines located in Ma-zandaran Province, northern Iran. The study was conducted on a monthly basis from February, 2012 to January, 2013. Laser granulometry was used to analyze the particle size distribution of suspended se-diment samples taken from up and downstream sections of the study mines. The results revealed that the level and intensity of mining activity affected particle size distribution of suspended sediments. Further statistical assessments in up and downstream sections of the mines proved that sorting, D50, mean, D90, kurtosis, skewness and D10 of the suspended sediment were not significantly influenced by mining activities at levels of 0.09, 0.11, 0.12, 0.15 to 0.69, 0.15–0.69, 0.77, 0.87, 0.97, respectively. While it was not statistically significant, we found that the type of mine and the level of the exploitation changed the particle size distribution of the suspended sediment.

关键词： Mine exploitation Particle size distribution Sediment granulometry Sediment temporal variations

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Camouflaged Uptake Following Incidental Focus-on-Form Episodes

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Journal of Linguistics and Education Research 2020年第1期3卷 1-10页

作者： Zahra gholami leila gholami Department of Education Kharazmi UniversityTehranIran Department of English Arizona State UniversityArizonaUnited States

The efficacy of focus-on-form(FonF)within the context of communicatively-oriented language activities is measured via *** is defined as learners’verbal responses immediately following either preemptive or reactive FonF instruction(Loewen,2004).The present study investigated what is(not)meant and(not)measured through this definition of *** on the audio-recorded analysis of 20 hours of communicatively–oriented interactions in an intermediate IELTS class with two teachers,this study investigates the frequency of preemptive and reactive incidental FonF,and the subsequent occurrence of uptake in an English as a foreign language *** study also provided an in-depth qualitative analysis of these classes through field notes,learner notes,and video-recorded data to explore the instances of uptake moves that were not captured through audio-recorded *** quantitative findings of this study demonstrated a very low and disappointing uptake ***,the study did not find a significant difference between reactive and preemptive FonF in terms of uptake ***,the qualitative data revealed a myriad of uptake instances not observable via the initial data *** on these findings,a new definition of uptake is suggested,which includes camouflaged uptake and learners’immediate oral responses to *** uptake is used to gauge the efficacy of incidental FonF in primarily meaning–oriented classes,it is concluded that audio-recorded data just show the tip of the iceberg as far as the uptake rate is ***,second language acquisition researchers are recommended to employ multiple indices to examine the effectiveness of FonF instruction.

关键词： Camouflaged uptake rate EFL Incidental focus on form Reactive FonF Preemptive FonF Uptake rate

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