检索结果-南通市图书馆

Assessment of soil erodibility and aggregate stability for different parts of a forest road

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Forestry Research 2014年第1期25卷 193-200页

作者： Aidin Parsakhoo Majid Lotfalian ataollah kavian Seyed ataollah Hosseini Department of Forestry Faculty of Forest SciencesGorgan Agricultural Sciences and Natural Resources University Associate Professors Department of ForestryFaculty of Natural ResourcesSari Agricultural Sciences and Natural Resources University Assistant Professor Department of Watershed ManagementFaculty of Natural ResourcesSari Agricultural Sciences and Natural Resources University

We measured erodibility and mean weight diameter （MWD） of soil aggregates in different parts of a forest road. Samples of topsoil were collected from cutslope, fillslope, road surface and forest ground to assess the texture, bulk density, moisture, CaCO3 and organic matter. Soil aggregate stability was determined by wet sieving. Soil erodibility on the road surface was 2.3 and 1.3 times higher than on the fillslope and cutslope, respectively. The forest soil had the lowest erodibility. Aggregate stability of cutslope and road surface were low and very low, respectively. There was a significant negative relationship between cutslope erodibility with CaCO3 and sand content. Cutslope erodibility increased with increasing silt, clay and moisture content. On fillslopes, MWD increased with in-creasing rock fragment cover, plant cover, litter cover, organic matter and sand. There was a strong negative correlation between fillslope erodibility and organic matter, sand and MWD. There was no significant difference between erodibility of bare soil and soils beneathRubus hyrcanusL. and Philonotis marchica （Hedw.） Brid.

关键词： road prism soil erodibility aggregate stability wet sieving Lat Talar forest

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

在线全文

学校读者我要写书评

暂无评论

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

Effects of rainfall patterns on runoff and soil erosion in field plots

在线全文

学校读者我要写书评

暂无评论

International Soil and Water Conservation Research 2015年第4期3卷 273-281页

作者： Mohamad Ayob Mohamadi ataollah kavian Department of Watershed Management Sari Agricultural Sciences and Natural Resources University(SANRU)SariMazandaranIran

Soil erosion processes during a storm are strongly affected by intra-storm variations in rainfall *** storm patterns,each with a different rainfall intensity variation were *** storm patterns were:(1)increasing rainfall intensity(2)increasing then decreasing intensity(3)decreasing intensity(4)decreasing then increasing *** each erosive rainfall(12 events),Runoff and suspended sediment samples were collected in each plot's tank which is located on hillslopes of the basin of *** storm characteristics and soil losses were plotted and equation of the line of best fit were *** of variance(ANOVA)was used to determine response of runoff and soil erosion to storm *** showed that in lower rainfall intensities a linear function fits the relationship between soil loss and rainfall intensity whereas this function tends to be non-linear at higher *** a strong non-linear relationship was found between different quartiles of storm and soil *** analysis revealed significant differences in total runoff,soil loss and sediment concentration across four storm patterns(P<0.001)but no differences in the runoff *** particular,storms with increasing rainfall intensity yielded highest quantities of eroded sediments,total runoff and highest sediment concentrations followed by increasing then decreasing,decreasing then increasing and decreasing intensity,respectively.

关键词： Storm patterns Soil erosion Rainfall intensity Erosion plot

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

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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

Mapping sediment mobilization risks:Prioritizing results obtained at watershed and sub-watershed scales

在线全文

学校读者我要写书评

暂无评论

International Soil and Water Conservation Research 2024年第3期12卷 600-614页

作者： ataollah kavian Seyedeh Nastaran Mirzaei Bahram Choubin Mahin Kalehhouei Jesús Rodrigo-Comino Department of Watershed Management Faculty of Natural ResourcesSari Agricultural Sciences and Natural Resources University(SANRU)Sari48181-68984Iran West Azarbajan Agricultural and Natural Resources Research and Education Center Soil Conservation and Watershed Management Research DepartmentAREEoUrmiaIran Department of Watershed Management Sciences and Engineering Faculty of Natural ResourcesTarbiat Modares University(TMU)NourMazandaranIran Departamento de Analisis Geografico Regional y Geografia Fisica Facultad de Filosofia y LetrasCampus Universitario de CartujaUniversity of Granada18071GranadaSpain

Soils are key natural resources for the Earth's system;however,human impacts,especially,soil erosion are considered serious ***,identifying and assessing effective factors to understand erosion hot spots at different scales is critical to developing effective land management plans and ensuring the sustainability of the *** study was conducted to determine and prepare an erosion risk map,but to prioritize the survey at different scales,such as sub-basin and watershed *** achieve this goal,geographic information system(GIS)and remote sensing data(RS)were used combining the analysis network process method(ANP)and ICONA model(Institute for the Conservation of Nature).As study case,we selected the degraded areas of the Gorganrood watershed located in the north of *** study area was obtained for very low,low,medium,high,and very high-risk classi-fications of 14.0,21.4,17.9,31.3,and 15.4%,*** from the ICONA model also indicated that 12.8,28.8,22.1,27.9,8.5,and 0.03%belong to very low,low,medium,high,very high,and without risk of erosion,*** to the validation results,it was found that the accuracy of ANP and ICONA models are 0.83 and 0.80,respectively,which indicates the suitability of the models for preparing the erosion map of the region is appropriate and useful for designing land management *** conclude that both models can be used to develop the erosion map potential and to prioritize sub-basins if a complete database of geomorphological characteriscs and human activities are accurate previously defined.

关键词： Analysis network process method Natural hazards Land management Land uses Land degradation

Runoff and sediment concentration of different parts of a road in Hyrcanian forests

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Forestry Studies in China 2013年第2期15卷 144-151页

作者： Majid LOTFALIAN Aidin PARSAKHOO ataollah kavian Seyed ataollah HOSSEINI Department of Forestry Faculty of Natural Resources Sari Agricultural Sciences and Natural Resources UniversitySari 737 Iran Department of Forestry Faculty of Forest Science Gorgan Agricultural Sciences and Natural Resources UniversityGorgan 386 Iran Department of Watershed Management Faculty of Natural Resources Sari Agricultural Sciences and Natural Resources UniversitySari 737 Iran

Road prisms, such as cutslopes, fillslopes and road surfaces, can be important contributors of sediment to streams in forested watersheds. In this study rainfall simulations were carried out on cutslopes, fillslopes, road surfaces and forest grounds in hardwood forests of Lolet and Lat Talar, Iran. Water at intensity of 32.4 mm·h-1 was sprayed from a nozzle onto a square area of 0.48 m2. Runoff was collected by water gauge every 4 min and then runoff and sediment parameters were measured in each plot. Results indicated that on road surfaces, the runoff coefficient was 63.28%. On the cutslopes and fillslopes, the runoff coefficients were 35.14% and 10.23%, respectively. On the forest ground as a control, the runoff coefficient was 5.90%. Runoff volume was 2.73 mL·s^-1 on the road surfaces and 1.52 mL·s^-1 on cutslopes. On fillslopes the runoff volume was 0.44 mL·s^-1 and on the forest ground 0.25 mL·s^-1 The greatest rate of soil loss was found on the cutslope （280.79 g·m-2·h-1）. The total soil loss from the cutslopes was two times higher than that from the road surfaces and six times higher than that from the fillslopes. We conclude that cutslopes can be considered the main source of sediments in our study sites, but the function of road surface as a source of runoff generation is more important.

关键词： runoff soil loss road prism rainfall simulation Hyrcanian forest

Autonomous fault-diagnosis and decision-making algorithm for determining faulty nodes in distributed wireless networks

在线全文

学校读者我要写书评

暂无评论

Frontiers of Information Technology & Electronic Engineering 2016年第9期17卷 885-896页

作者： Adel KHOSRAVI Yousef SEIFI kavian Electrical Engineering Department Faculty of Engineering Shahid Chamran University of Ahvaz

In this paper, we address fault-diagnosis agreement(FDA) problems in distributed wireless networks(DWNs) with arbitrary fallible nodes and healthy access points. We propose a new algorithm to reach an agreement among fault-free members about the faulty ones. The algorithm is designed for fully connected DWN and can also be easily adapted to partially connected networks. Our contribution is to reduce the bit complexity of the Byzantine agreement process by detecting the same list of faulty units in all fault-free members. Therefore, the malicious units can be removed from other consensus processes. Also, each healthy unit detects a local list of malicious units, which results in lower packet transmissions in the network. Our proposed algorithm solves FDA problems in 2t+1 rounds of packet transmissions, and the bit complexity in each wireless node is O(nt+1).

关键词： Fault diagnosis Decision making Byzantine agreement Distributed wireless networks Consensus

Comments on Asian Stroke Criteria

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2009年第11期4卷 958-960页

作者： kavian Ghandehari Department of Neurology Ghaem HospitalFaculty of MedicineMashhad University of Medical Sciences

The Asian Stroke Criteria （ASC） was developed to detect etiology and topography of brain infarction. The ASC was designed by stroke neurologists and approved by the University of Alberta, Canada in 2003. In the first validation step, inter-rater reliability of ASC was evaluated. The inter-rater agreement, according to the ASC system, is much higher than other classifications with moderate inter-observer reliability. In the second validation step, ASC has been used successfully in Khorasan stroke registries.

关键词： stroke infarction classification etiology

Preparation of a novel supported electrode comprising a nickel(Ⅱ)hydroxide-modified carbon paste electrode(Ni(OH)_2-X/CPE)for the electrocatalytic oxidation of formaldehyde

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Catalysis 2016年第1期37卷 159-168页

作者： Safura kavian Seyed Naser Azizi Shahram Ghasemi 马赞德兰大学化学学院分析部马赞德兰大学化学学院

We prepared a novel nickel（II）hydroxide-modified carbon paste electrode（Ni（OH）2-X/CPE）for the electrocatalytic oxidation of *** electrode was prepared by a simple method without the use of linking *** prepared Ni（OH）2-X/CPE material was characterized by scanning electron microscopy and energy dispersive X-ray *** electrochemical performance of the proposed electrode was investigated using cyclic voltammetry,electrochemical impedance spectroscopy,and *** results indicate that Ni（OH）2-X/CPE exhibits good electrocatalytic activity with regards to formaldehyde oxidation owing to its nanoporous structure and the large surface area of zeolite *** values of the electron transfer coefficient and the catalytic rate constant were 0.7 and 6.1 × 104 cm3/（mol·s）,***,the proposed electrode,which showed remarkable electroactivity with regards to formaldehyde oxidation with long-term stability and good reproducibility,could be useful in fuel cells.

关键词： Fuel cell Electrocatalyst Porous NaX nanozeolite Formaldehyde Chronoamperometry