جستجوی مقالات مرتبط با کلیدواژه « تعداد منافذ » در نشریات گروه « آب و خاک »

The major topic in the study of the compaction is the soil pore size and type. Soil compaction can be significantly reduced with changes in soil pore volume, water infiltration and availability of plants to air and water. Sum effects of the above may lead to reduced soil quality. Therefore a field study was performed to evaluate the effect of soil compaction on movement of water in the pores (coarse and medium size pores) of loamy soil. A completely randomized block was designed with three replications, applying blank (No teraffic passing), once, twice, three times, four times and eight times of tractor passings. Number of pores and percent flow through them with effective porosity and hydraulic conductivities (saturated and unsaturated), was determined in the field using disc infilterometer in four potentials (0, -3, -5 and -15 cm of water). Our results revealed thatin all of the treatments medium size pores were many times of large ones hence, both sizes decreased with compaction. Results of disc Infilterometer showed that coarse and medium size pores (macro and meso pores) of eight times tractor passings relative to control decreased 85 and 62.5 percent respectively. The majoreffect of compaction was onthelarge size pores. The mediumpore sizewasmore impressed than large pore size. Number of medium poresin the soil was less than large ones.