Tillage effects and specific energy requirements of rotary tillage |
| |
| Authors: | H Ellen |
| |
| Institution: | Department of Agricultural Engineering, University of Nairobi, P.O. Box 30197, Nairobi Kenya |
| |
| Abstract: | Rotary tillage experiments were carried out under laboratory conditions in 3 types of Dutch soil. The moisture contents were set at 6 levels. Two tools were used; a knife blade and a tine. The energy required to work the soil was assessed with a pendulum.The specific energy requirement was expressed in units per volume of loosened soil, EV (kJ m?3) and also in units per surface area of loosened soil, EA (kJ m?2). In silty clay loam EV ranged between 153 and 160 kJ m?3 for the knife blade, and increased from 170 to 280 kJ m?3 for the tine, when the moisture content increased from 17 to 22%. EA increased from 2.5 to 9 kJ m?2 × 10?1 for the knife blade and from 3.8 to 10.5 kJ m?2 × 10?1 for the tine, when the moisture content increased from 17 to 22%.In sandy loam EV decreased from 110 to 75 kJ m?3 for the knife blade and from 165 to 130 kJ m?3 for the tine, when the moisture content increased from 9.5 to 17% EA increased from 1 to 2.5 kJ m?2 × 10?1 for the knife blade and increased from 2.7 to 2 kJ m?2 × 10?1 for the tine, when the moisture content increased from 9.5 to 17%.In silty loam EV decreased from 117 to 95 kJ m?3 for the knife blade and from 170 to 137 kJ m?3 for the tine, when the moisture content increased from 17 to 22%. EA increased from 3.7 to 5 kJ mm?2 × 10?1 for the knife blade, and from 3 to 5.5 kJ m?2 × 10?1 for the tine, when the moisture content increased from 17 to 22%.The energy requirement was related to penetration resistance, shearing resistance and modulus of elasticity. In silty clay loam the penetration resistance decreased from 3.9 to 2.6 MPa × 10?1, the shear resistance hardly changed and ranged between 0.8 and 0.9 MPa × 10?1, and the modulus of elasticity decreased from 46 to 23 MPa × 10?1, when the moisture content increased from 17 to 22%.In sandy loam the penetration resistance decreased from 5.5 to 1.9 MPa × 10?1, the shear resistance decreased from 0.6 to 0.4 MPa × 10?1 and the modulus of elasticity decreased from 84 to 15 MPa × 10?1, when the moisture content increased from 9.5 to 17%. In silty loam, the penetration resistance decreased from 3.6 to 1.7 MPa × 10?1, the shear resistance decreased from 0.6 to 0.4 MPa × 10?1 and the modulus of elasticity decreased from 58 to 11 MPa × 10?1 when the moisture content increased from 17.5 to 22%. |
| |
| Keywords: | Address all correspondence to State Agricultural College Prof Van Hallstraat 9726 AG Groningen The Netherlands |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
