Spatial and temporal effects of direct drilling on soil structure in the seedling environment

摘要: Despite more than 30 years of research and practical experience the interest in shallow tillage especially direct drilling has remained low Scandinavia. Excessive compaction topsoil layer is one major problems encountered when adapting particular. The purpose this study was to evaluate temporal spatial effects two different techniques on bulk density penetration resistance near seed environment. A sandy loam growing small grain cereals followed during first 3 after conversion from conventional reveal short-term changes soil structure. field experiment with four blocks conducted 1999–2001 where a mouldboard ploughing–harrowing system (PL) compared performed by either chisel coulter drill (DD-C) or single disc (DD-D). Effects were measured first, second third year crop establishment (T1, T2 T3). Bulk determined at 0–100 mm depth using dual probe gamma-ray transmission system. Penetration recorded 0–150 depth. At column samples (diameter: 180 mm, height: 200 mm) taken row through centre. these 10 mm×10 grid micropenetrometer (3 cone base diameter) 0 approximately 150 Two each treatment analysed medical CT-scanner determine differences density. Irrespective type gave fast arable below seeding shifting ploughing drilling. Soil strength substantially higher already (i.e., maximum 0.4 1.2 MPa, for PL DD-D/DD-C, respectively). Critical high (>2.0 MPa) levels (>1.5 g cm-3) reached same level T3. DD-C produced favourable environment DD-D drill. 40 loose granular above no indication effect found treatment. In contrast, as well laboratory results indicated compacting lack itself, evidence suggest that periodic non-inversion loosening lower part needed drilled moist cool climate.