skidding operations can cause considerable and wide spread soil disturbance. the objective of this study was to evaluate the effects of ground skidding operations on soil compaction, moisture content, and total porosity at different levels of slope and traffic frequency. four levels of traffic intensity (3, 8, 13, and >13 passes of a crawler tractor onezhets ? 110) and three levels of slope ( 2...

soil colloid particles influence soil chemical and physical properties by their surface electrical charge. with respect to the importance of this issue from both agricultural and environmental points of view, charging behavior of a kaolinite sample was studied in the ph range of 4 to 10 and at three background electrolyte concentrations, including 0.005, 0.05, 0.5 m nacl, by potentiometric titr...

1. A considerable advance has been made in the study of the fulvic extract of soil organic matter. A new method has been introduced whereby the fulvic extract is separated by a selective adsorption technique into four distinct fractions. 2. These fractions have been obtained from the fulvic extracts from four widely diverse types of soil. 3. A preliminary examination of the chemical properties ...

Large amounts of fertilizers and pesticides applied annually to agricultural soils improve the physical and chemical properties of soil but, when they are applied without control they can cause serious environmental problems. The farms of Tizayuca in Hidalgo State produce about 30000 tons of manure per day, which are applied indiscriminately in the same region for agricultural use. The aim of t...

This study determined some spectral characteristics and relationship between Landsat spectral reflectance and soil surface color in the arid region of Iran (Kashan). The study carried out in the kashan area that covers 90000 ha. Consisting of mountain, hills and flood plain. Enhanced Thematic Mapper (ETM+) data collected on July 2002 were used for this research. The color composite images produ...

Soil movement by tillage redistributes soil within the profile and throughout the landscape, resulting in soil removal from convex slope positions and soil accumulation in concave slope positions. Previous investigations of the spatial variability in surface soil properties and crop yield in a glacial till landscape in west central Minnesota indicated that wheat (Triticum aestivum) yields were ...