الفهرس | Only 14 pages are availabe for public view |
Abstract During the last decade. Many kinds of harvesting machines have been introduced to Egypt and different sizes of them especially rice combine harvesters are now available for use on the Egyptian farm. It was noticed that during the operation of harvesting machines, wheel traffic causes the soil to be compacted. The problems concerned with soil compaction are more sever in soil with high moisture content, especially when the harvesting equipments are loaded with several tons of grain in addition to its own weight. The compacted soil needs higher energy to be prepared for the next crop in addition to the lower crop yield. The main purpose of this study was to determine the effect of soil compaction induced by mechanical harvesters on the physical properties of soil such as, bulk density, pore volume, penetration resistance and track (sinkage) depth. Soil compaction was induced by three different types of combine harvesters under three different soil moisture contents (54.31, 49.87 and 42.57% d.b.), two different weights of combine harvesters (loaded and empty grain tank), two levels of tire inflation pressure (1.0 and 1.5 bar), multiple traffic (wheel or crawler) passes and different slip rations. |