Track 2-09: Soil Quality, Biology and Plant-Soil Interactions
Description
The understanding of how soil physical properties respond to differing grazing practices may help explain the main causes of pasture degradation. Soil compaction has been shown to be a main degradation form of soil and the knowledge of techniques to quantify and rectify this are necessary to maintain optimal yields. This research aims to measure the rupture lines of red yellow latossol under differing pasture grazing practices compared to cropping and a natural forest. With this information it is aimed to calculate the correction factor for stocking rates and traffic of tillage tools. The differing soil management practices examined was, pasture grazed by sheep, and dairy cattle, a maize crop in no tillage cover-crop system and a natural forest. To quantify the soil physical changes, the direct shear test was used, which calculated the resultant force of a load. The resultant forces of the natural forest were compared against pasture systems and crop system, and a correction factor for stocking rates was calculated. The samples of Red yellow Latossol were equilibrated in the matrix potential (ψ): -6 kPa. In the shear test, the normal stress used was the 450kPa. The correction factor (CF) indicates whether the soil has structural degradation compared to natural forest. Values less than 1 indicated soil degradation. The pastures grazed by sheep and dairy cattle had values observed to be less than 1, excessive loads at high soil moisture may be attributed to this soil structural deformation. For these systems, grazing management and stocking rates should be corrected. The correction factor gives an indication of the magnitude of management change that is required (i.e. the stocking rate decreased). The crop area was found to have no soil strength issues, using the stress test.
Included in
Comparing Soil Compaction under Different Grazing Systems with a Virgin Forest Soil to Determine Optimal Stocking Rates
The understanding of how soil physical properties respond to differing grazing practices may help explain the main causes of pasture degradation. Soil compaction has been shown to be a main degradation form of soil and the knowledge of techniques to quantify and rectify this are necessary to maintain optimal yields. This research aims to measure the rupture lines of red yellow latossol under differing pasture grazing practices compared to cropping and a natural forest. With this information it is aimed to calculate the correction factor for stocking rates and traffic of tillage tools. The differing soil management practices examined was, pasture grazed by sheep, and dairy cattle, a maize crop in no tillage cover-crop system and a natural forest. To quantify the soil physical changes, the direct shear test was used, which calculated the resultant force of a load. The resultant forces of the natural forest were compared against pasture systems and crop system, and a correction factor for stocking rates was calculated. The samples of Red yellow Latossol were equilibrated in the matrix potential (ψ): -6 kPa. In the shear test, the normal stress used was the 450kPa. The correction factor (CF) indicates whether the soil has structural degradation compared to natural forest. Values less than 1 indicated soil degradation. The pastures grazed by sheep and dairy cattle had values observed to be less than 1, excessive loads at high soil moisture may be attributed to this soil structural deformation. For these systems, grazing management and stocking rates should be corrected. The correction factor gives an indication of the magnitude of management change that is required (i.e. the stocking rate decreased). The crop area was found to have no soil strength issues, using the stress test.
