in forest harvesting, there is an ongoing trend to increase constantly the size, power and load of logging machines. this may cause soil degradation in forest ecosystems as the passes of these machines modify important soil structural characteristics. the present study was conducted to examine impact of skidding traffic, trail slope, traffic frequency, and soil depth on bulk density and soil co...

the split-block experimental design with three replications was used to study the effect of subsoiling in different distances from drain axison soil salinity,and wheat yield. the measurements included soil cone index, soil bulkdensity, infiltration rate and electrical conductivity of saturated extract. each treatment was composed of two factors. the main factors consisted of 3 different distanc...

soil is a nonrenewable source that needs considerable management to prevent physical deteriorationby erosion and compaction. compacted soil causes low fertility and yield. the purpose of this study isto investigate the effect of viscoelastic properties of soil and to determine important factors oncompaction. furthermore, stress distribution, prediction of soil compaction and simulation of its e...

the prevalent method of irrigation in paddy fields in iran is continuous ponding, which changes to intermittent method at the time of water shortage. soil cracks are the main problem in intermittent irrigation. in this study, effects of adding rice straw on some soil physical characteristics and cracks were studied in paddy soils of the guilan province of iran. the experiment was performed as s...

assessment and management of the environmental impacts of forest harvesting operations have become increasingly critical factors in practicing commercial forestry. this study investigated soil disturbance from a forest logging system operation on an 8-hectare mixed broadleaved stand in compartment no. 309 in gorazbon district in kheyrud educational and research forest. the objective of this stu...

the effects of traffic frequency and skid trail slope on dry bulk density, litter mass and rutting are examined. treatments included a combination of four different traffic frequencies (3, 7, 14, and 20 passes of a rubber skidder) and three levels of slope ( 20%.) the results showed that dry bulk density, rut depth and soil displacement increased with the increase of traffic frequency and slope...

in order to study the effects of sugar cane harvest machinery traffic on bulk density and cone index variation, a survey was conducted in 10 farms of deabel khozaiee sugarcane agro-industrial company, ahvaz, in 2006. in this experiment, two types of harvesters including wheel half track and tire wheels with 14 tons of weight, versus two types of tractor and basket transporters, with 10 and 18 t...