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Prediction of the soil erosion in a forest and sediment yield from road network through GIS and SEDMODL

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International Journal of Sediment Research 2014年第1期29卷 118-125页

作者： Aidin PARSAKHOO majid lotfalian Ataollah KAVIAN Seyed Ataollah HOSSEINI Department of Forestry Gorgan Agricultural Sciences and Natural Resources University Department of Watershed Management Sari Agricultural Sciences and Natural Resources University Department Forestry Sari Agricultural Sciences and Natural Resources University University of Tehran

This study was conducted to classify water erosion risk for a deciduous forest and to predict the amount of sediment yield from forest road network.GIS in combination with AHP was used for determining the soil erosion risk degrees of forest.Beside,sediment yield from forest roads with gravel and asphalted surfacing was estimated using SEDMODL.Rainfall simulator was used in calibration and validation process of model.Results showed that47.9%of forest soil is classified from moderate to very high vulnerability.32.3%of roads were located in soil erosion risk class of very high.This class is generally found in the eastern region of forest,while areas with very low risk are found in the south western part.14.6%of the forest roads were ranked as having very low sediment yield.Only 61 segments out of 339 segments of forest road network delivered sediment to the ravine network.The estimated annual sediment yield for all of road sections by SEDMODL and rainfall simulator were 10,935.45 and10,509.29 g m,respectively.Results of the calibration and validation process showed that the variation accounted for in the predicted values by SEDMODL with the observed values under rainfall simulation was 3.90%.Best management practices(BMP) must be considered for the areas with high degrees of erosion risk.

关键词： Soil erosion Forest road GIS SEDMODL

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

An evaluation of harvesting costs in present and planned operations: case study—Waston District of Mazandaran Wood and Paper Industries

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Journal of Forestry Research 2018年第1期29卷 215-220页

作者： majid lotfalian Mohammad Ali Akbari Gorji Seyed Ataollah Hoseini Maryam Kazemi Department of Forestry Faculty of Natural Resources Sari University of Agricultural Sciences and Natural Resources Forestry Master of Science Graduates Faculty of Natural Resources Sari University of Agricultural Sciences and Natural Resources Department of Forestry Faculty of Natural ResourcesTehran University

Amongst all forest utilization phases, harvesting plays a key role as the beginning phase of the utilization cycle and has a significant effect on the following phases.In this research, in order to examine the reduction of costs with respect to present and planned operations, the starting time of the harvesting or cutting phase and work flow were recorded. The starting time of each phase of the entire operation was recorded as well. Before harvesting the marked tree, the appropriate felling direction was determined and the azimuth of the correct direction was taken.The results indicate that there was not a meaningful relationship between the differences in direction of a leaning tree compared with the felling direction. However, there was a significant relationship between the difference of the defined and felling direction and the difference in tree leaning and defined direction. The same trend was observed between tree leaning and felling directions and tree leaning and defined directions. On the other hand,there was no significant relationship between tree leaning and felling directions and the defined and tree felling directions. In addition, this research shows that with an increase in tree volume, the time for tree cutting rose.Furthermore, when the difference of tree leaning and felling direction decreased, the time to cut the tree declined.The regression equation is Y = 168.9–0.14（the difference between tree leaning and felling direction）＋ 0.7（volume）.

关键词： Chainsaw Felling direction Cutting time Tree leaning direction

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

Use of mesophilic and thermophilic bacteria for the improvement of copper extraction from a low-grade ore

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International Journal of Minerals,Metallurgy and Materials 2011年第2期18卷 138-143页

作者： E.Darezereshki M.Schaffie M.lotfalian S.A.Seiedbaghery M. Ranjbar Department of Mineral Processing Engineering Bahonar University Energy and Environmental Engineering Research Center (EERC) Bahonar University Department of Chemical Engineering Bahonar University Industrial Mining Research Center (IMRC) Bahonar University Hydrometallurgy Research Unit R & D Center Sarcheshmeh Copper Complex

Bioleaching was examined for copper extraction from a low grade ore using mesophilic and moderate thermophilic bacteria. Five equal size columns were used for the leaching of the ore. Sulfuric acid solution with a flow rate of 3.12 L·m-2·h-1 and pH 1.5 passed through each column continuously for 90 d. In the first and the second column, bioleaching was performed without agglomeration of the ore and on the agglomerated ore, respectively. 28wt% of the copper was extracted in the first column after 40 d, while this figure was 38wt% in the second column. After 90 d, however, the overall extractions were almost the same for both of them. Bioleaching with mesophilic bacteria was performed in the third column without agglomeration of the ore and in the fourth column on the agglomerated ore. After 40 d, copper extractions in the third and the fourth columns were 62wt% and 70wt%, respectively. Copper extractions were 75wt% for both the columns after 90 d. For the last column, bioleaching was performed with moderate thermophilic bacteria and agglomerated ore. Copper extractions were 80wt% and 85wt% after 40 and 90 d, respectively. It was concluded that crushing and agglomeration of the ore using bacteria could enhance the copper extraction considerably.

关键词： bioleaching mesophilic bacteria thermopilic bacteria copper extraction agglomeration.

Synthesis and Characterization of Molybdenum（VI） Complexes with 1,10-Phenanthroline

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Journal of Chemistry and Chemical Engineering 2012年第4期6卷 368-371页

作者： Roya Ranjineh Khojasteh Sajedeh lotfalian Saremi Department of Chemistry lslamic Azad University North Tehran Branch Tehran 1ran