Showing 3 results for Forest Soil
R Molavi, M Baghernejad, E Adhami,
Volume 13, Issue 49 (10-2009)
Abstract
Fire is widely used to clear farms in Iran, while there is little information regarding the effects of fire on the characteristics, especially mineralogy of soils. The objectives of the present study were to 1) compare some physico-chemical properties of burned and unburned soils and 2) evaluate minerals transformation in top soil layer resulting from increasing temperature. Soil samples were taken from 0-5 and 5-15 cm depths of two burned places, an agricultural soil from Takht-e-Jamshid area and Bamoo forest, in four replications. Physico-chemical analyses were carried out on burned and unburned samples. X-ray diffraction technique was used to identify minerals of clay fraction in 0-5 cm depth burned and unburned soil, and also to compare transformation of minerals (if any) after heating at 300˚C and 600˚C for 2, 4, 8 and 12 h. Burning increased soil pH and sand sized fraction in 0-5 cm, and P and K in both depths of Bamoo forest. Changes in soil properties of agricultural filed were negligible. XRD analyses showed the reduction in the intensity peaks of chlorite and illite after burning. Lower relative quantity of chlorite and illite was observed in various times of 300˚C treatment in comparison to control, while they were not observed in 8 and 12 h of 600˚C. No change was observed in the peak of quartz in forest and field soils after burning and after various heat treatments.
S. Ezzati , A. Najafi,
Volume 16, Issue 61 (10-2012)
Abstract
Increase in soil bulk density and reduces in porosity and infiltration rate are the most common disturbances during timber harvesting and ground-base skidding. The present study was conducted to study soil physical properties e.g., soil bulk density, moisture, porosity and soil hydrological properties e.g., soil infiltration from ground-base skidding in twenty years since logging. After initial survey, four abandonment skid trails were selected with similar pedologic, climatic conditions and physiographic and different age in Necka-Zalemrod catchment in east of Mazandaran province. Results indicated that impacts of machinery traffices in high traffic intensity have remained yet 20 years since logging. Means soil bulk density, porosity and void ratio were 42.4 greater, 24.6 and 46.7 percent, respectively, lower than the undisturbed areas. The least infiltration rate was recorded in 1-5 years old skid trail, so the reduction of water was not considerable within 18 minutes after experiment into soil in inner ring in this skid trail. Results in each skid trail firmed that in low traffic intensity soil physical and hydrologic properties was tent to “normal” recover in compare to the undisturbed areas.
S. Ashrafi-Saeidlou, Mh. Rasouli-Sadghiani, M. Barin,
Volume 21, Issue 3 (11-2017)
Abstract
The Firing effect on soil depends on its intensity and duration. In order to investigate influence of different firing backgrounds on some soil physical and chemical properties, 80 soil samples were taken from two depths (0-5 cm and 5-20 cm) with different time of firing background (2 and 12 months). Some soil physical and chemical characteristics were measured at soil samples. The results showed that there was a significant difference in the amount of pH, EC, bulk density and ammonium in soils with different history of burning. The amount of studied indices increased after firing in burned soils compared to the control ones. However 12 months later they reach to their pre-fire levels. Total nitrogen amount in soils with 2 and 12 months firing history were 1.18 and 1.11 times higher than the control soils, respectively. The amount of organic carbon in surface depth (0-5 cm) of burned soils with 2 and 12 month firing backgrounds 37.25 and 24.7 percent increased in comparison to control soils, respectively. Also, fire led to a significant reduction in the amount of clay (29.25 percent) in burned areas compared to the control ones. Soil particle size distribution in control sites were in clay up to loam and in burned areas were in clay loam up to sandy loam classes. Therefore forest firing causes obvious changes in soil properties, remediation of which takes more than one year.
