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

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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

Soil loss and displacement by heavy equipment in forest road subgrading projects

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International Journal of Sediment Research 2009年第2期24卷 227-235页

作者： Aidin PARSAKHOO seyed ataollah hosseini Majid LOTFALIAN Hamid JALILVAND M.Sc. Student of Forest Engineering Faculty of Natural ResourcesMazandaran University Department of Forestry Faculty of Natural ResourcesMazandaran University

Forest soil is an important component of the natural environment,and is a primary medium for many biological activities. In this study,soil loss and displacement by excavator and bulldozer(heavy equipments) were measured on cut and fills slopes of forest roads located in Mazandaran province,Iran. The volumes of soil losses were estimated by prismoidal analyses of cut and fill slopes deformation between two time treatments(under subgrading and two years later) in slope classes of 30-50% and 50-70%. Weights of soil losses were calculated by multiplying the volumes of soil losses(cm3) to the general bulk density(1.3g/cm3) . Soil displaced area by heavy equipment was evaluated according to earth working width. Results indicated that heavy equipment has significant effect on deformation of cut slope gradient and fill slope length(p<0.0001) . During the two-year period,the cut(p<0.0002) and fill(p<0.0001) slope gradients were significantly deformed in different slope classes. The average soil loss by excavator and bulldozer were 160.35 t/ha·yr and 429.09 t/ha·yr,respectively. Moreover,the soil displaced area during the subgrading process by bulldozer was greater than excavator in both two slope classes(p<0.05) . Soil loss and displacement in forest roads can be reduced by applying powerful excavators in subgrading project,especially in steep terrains.

关键词： Soil losses Soil displacement Heavy equipment Forest road Subgrading

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

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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

Effect of shelterwood cutting method on forest regeneration and stand structure in a Hyrcanian forest ecosystem

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Journal of Forestry Research 2010年第3期21卷 265-272,395页

作者： Mohammad Reza Pourmajidian Hamid Jalilvand Asghar Fallah seyed ataollah hosseini Aidin Parsakhoo Amin Vosoughian Ali Rahmani Department of Forestry Faculty of Natural ResourcesSari Agricultural Sciences and Natural Resources University Department of Forestry Faculty of Natural ResourcesMazandaran University

A study was carried out to evaluate the effect of shelterwood cutting methods on stand structure and regeneration density. Data were collected from a northern hardwood forest stands in Iran with Fagus orientalis Lipsky as dominant species, with/without shelterwood cutting operation. Results clearly demonstrate that the management of Fagus orientalis Lipsky with shelterwood cutting system affected the frequency and diversity of the understory herbaceous species. The frequency of Viola silvestris Lam., Asperula odorata L., Carex spp. and Rubus hyr-canus Juz increased significantly after shelterwood cutting. The DBH （diameter at breast height） of commercial species in control stands （57.50±2.15 cm） was greater than that in treated stands （50.67±1.88 cm）, whereas the total height of trees was similar between treated and control plots （21±0.5 m）. The number of Parrotia persica seedlings increased by 13.2% from 1995 to 2005 whereas the number of Fagus orientalis and Carpinus betulus seedlings significantly decreased from 1995 to 2005. In conclusion, it confirms that instead of shelterwood cutting method other silvicultural practices such as selection cutting method should be applied for the mountainous beech stands of Hyrcanian forests.

关键词： Shelterwood cutting stand structure regeneration Fagus orientalis Lipsky

New insights on the role of chondroitin sulfate proteoglycans in neural stem cell–mediated repair in spinal cord injury

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Neural Regeneration Research 2025年第6期20卷 1699-1700页

作者： seyed Mojtaba hosseini Soheila Karimi-Abdolrezaee Department of Physiology and Pathophysiology Spinal Cord Research CentreRady Faculty of Health SciencesUniversity of ManitobaWinnipegMBCanada Manitoba Multiple Sclerosis Research Center WinnipegMBCanada Children Hospital Research Institute of Manitoba WinnipegMBCanada

Extensive neurodegeneration is a hallmark of traumatic spinal cord injury (SCI) that underlies permanent sensorimotor and autonomic impairments (Alizadeh et al.,2019).Following the primary impact,the spinal cord undergoes a cascade of secondary injury mechanisms that are driven by disruption of the blood-spinal cord ba rrier,vascula r inju ry,glial reactivity,neu roinfla mmation,oxidative stress,lipid peroxidation,and glutamate excitotoxicity that culminate in neuronal and oligodendroglial cell death,demyelination,and axonal damage(Alizadeh et al.,2019).To achieve a meaningful functional recovery after SCI,regeneration of new neurons and oligodendrocytes and their successful growth and integration within the neural network are critical steps for reconstructing the damaged spinal cord tissue (Fischer et al.,2020).

关键词： peroxidation Fischer injury

Prediction of bed load sediments using different artificial neural network models

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Frontiers of Structural and Civil Engineering 2020年第2期14卷 374-386页

作者： Reza ASHEGHI seyed Abbas hosseini Department of Civil Engineering Science and Research BranchIslamic Azad UniversityTehranIran

Modeling and prediction of bed loads is an important but difficult issue in river *** introduced empirical equations due to restricted applicability even in similar conditions provide different accuracies with each other and measured *** this paper,three different artificial neural networks(ANNs)including multilayer percepterons,radial based function(RBF),and generalized feed forward neural network using five dominant parameters of bed load transport formulas for the Main Fork Red River in Idaho-USA were *** optimum models were found through 102 data sets of flow discharge,flow velocity,water surface slopes,flow depth,and mean grain *** deficiency of empirical equations for this river by conducted comparison between measured and predicted values was approved where the ANN models presented more consistence and closer estimation to observed *** coefficient of determination between measured and predicted values for empirical equations varied from 0.10 to 0.21 against the 0.93 to 0.98 in ANN *** accuracy performance of all models was evaluated and interpreted using different statistical error criteria,analytical graphs and confusion *** the ANN models predicted compatible outputs but the RBF with 79%correct classification rate corresponding to 0.191 nctwork error was outperform than others.

关键词： bed load prediction artificial neural network modeling empirical equations

Enhanced microstructural and mechanical properties of Stellite/WC nanocomposite on Inconel 718 deposited through vibration-assisted laser cladding

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International Journal of Minerals,Metallurgy and Materials 2022年第2期29卷 327-334页

作者： Hossein hosseini-Tayeb seyed Mahdi Rafiaei Daneshpajoohan Pishro Higher Education Institute IsfahanIran Department of Materials Science and Engineering Golpayegan University of TechnologyGolpayeganIsfahanIran

Stellite-21/WC nanopowders were deposited on Inconel through vibration-assisted laser cladding with different laser *** and scanning electron microscopy,hardness measurements,and wear characterizations were employed to understand the microstructural and mechanical behaviors of the *** showed that varying the cooling rate exerted remarkable effects on the microstructure of the as-cladded ***,increasing the laser power from 150 W to 250 W increased the heat input and the *** was affected by the scanning rate and powder feeding rate at a high laser power of 250 *** WC nanoparticles were added as reinforcement,the dilution magnitude intensified while the hardness value increased from HV 350 to HV *** wear characterizations indicated that the composites containing 3 wt%WC nanoparticles possessed the highest wear resistance.

关键词： Stellite WC nanoparticles mechanical properties laser cladding

Simultaneous Employment of Generation Rescheduling and Incentive-based Demand Response Programs for Congestion Management in Case of Contingency

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Journal of Modern Power Systems and Clean Energy 2022年第4期10卷 902-912页

作者： seyed Erfan hosseini Alimorad Khajehzadeh Mahdiyeh Eslami Department of Electrical Engineering Kerman branchIslamic Azad UniversityKermanIran

Relieving congestion significantly influences the operation and security of the transmission ***,the congestion alleviation of transmission network in all power systems is ***,it could prevent price spikes and/or involuntary load shedding and impose high expenses on the transimission network,especially in case of ***,the increasing or decreasing generation rescheduling has been used as one of the most imperative approaches for correctional congestion management when a contingency ***,demand response programs(DRPs)could also be a vital tool for managing the ***,the simultaneous employment of generation rescheduling and DRPs is proposed for congestion management in case of *** objective is to reschedule the generation of power plants and to employ DRPs in such a way so as to lessen the cost of *** crow search algorithm is employed to determine the *** accuracy and efficiency of the proposed approach are assessed through the tests conducted on IEEE 30-bus and 57-bus test *** results of various case studies indicate the better performance of the proposed approach in comparison with different approaches presented in the literature.

关键词： Congestion management demand response generation rescheduling transmission economy transmission lines

Linking morphological and ecophysiological leaf traits to canopy dieback in Persian oak trees from central Zagros

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Journal of Forestry Research 2019年第5期30卷 1755-1764页

作者： Ahmad hosseini seyed Mohsen hosseini Juan Carlos Linares Department of Natural Resources AREEOIlam Agricultural and Natural Research and Education CenterIlam 69317-73835Iran Faculty of Natural Resources&Marine Sciences Tarbiat Modares UniversityNoorMazandaran 46417-76489Iran Department of Physical Chemical and Natural SystemsUniversity Pablo de OlavideCarretera de Utrera Km 141013 SevilleSpain

Intraspecific variability in morphological and ecophysiological leaf traits might be theorized to be present in declining populations,since they seem to be exposed to stress and plasticity could be *** we focused on declining Persian oaks(Quercus brantii ***(Jaub and Spach)Zohary)in the Zagros Mountains of western Iran,representing the most important tree species of this *** selected trees with contrasting crown dieback,from healthy to severely defoliated,to investigate the relationships between canopy dieback and leaf morphology,water content and *** also measured esterase and peroxidase,as enzymatic antioxidants and indicators of contrasting *** showing moderate to severe defoliation showed higher leaf mass area(LMA),reduced relative water content(RWC),and lower stomatal density(SD).Increasing LMA indicates a more sclerophyllic structure,according to drier *** did not find significant differences in leaf pigments(chlorophyll a and b,and carotenoids)among crown dieback classes,suggesting that Persian oak trees are able to maintain accurate photochemical efficiency,while reduced RWC and SD suggest hydraulic *** results do not provide a consistent pattern as regards enzymatic antioxidant defense in Persian *** leaf traits would be important drivers of future adaptive evolution in Persian oak,leading to smaller and thicker leaves,which have fitness benefits in dry ***,drought responses may be critically affecting carbon uptake,as photosynthetic compounds are less effectively used in leaves with higher sclerophylly.

关键词： Crown dieback Drought Leaf mass area Oak decline Quercus brantii Stomatal density Sclerophylly