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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

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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

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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

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