assessment of effect of road or road construction on soil physical and chemical properties in northern forests of iran

forests are an important economic source for human and have key role in nutrient cycle, hydrology and ecosystem performance, any interference in this vital ecosystem causes to damage to forests. mechanical logging and road construction in forest areas have led to much soil compaction. soil physical and chemical properties were studied in parts of road and non-road in the darabkola forest of iran. to investigate the soil properties, sixty samples of the top soil (0–20 cm deep) in two parts of forest ground and forest road surface were collected by cylinder for physical and chemical analysis: forest ground (30 samples) and forest road surface (30 samples). also, soil compaction and runoff production investigated in mentioned parts. therefore, produced runoff volume due rainfall in two studied parts was measured in equal area after the natural rainfall. the results showed that there was significant difference among soil different properties rate and too produced runoff rate in two studied parts. correlation matrix results in part of forest road indicated that there was significant negative and positive correlation between runoff and silt, clay, bulk density, lime and gravel, organic matter, ph, ec respectively and too in part of forest ground there was significant negative and positive correlation between runoff and moisture, clay, silt and gravel, organic matter, ph, ec respectively