Is conservation tillage suitable for organic farming? A review

Abstract

Conservation tillage covers a range of tillage practices, mostly non‐inversion, which aim to conserve soil moisture and reduce soil erosion by leaving more than one‐third of the soil surface covered by crop residues. Organic farmers are encouraged to adopt conservation tillage to preserve soil quality and fertility and to prevent soil degradation – mainly erosion and compaction. The potential advantages of conservation tillage in organic farming are reduced erosion, greater macroporosity in the soil surface due to larger number of earthworms, more microbial activity and carbon storage, less run‐off and leaching of nutrients, reduced fuel use and faster tillage. The disadvantages of conservation tillage in organic farming are greater pressure from grass weeds, less suitable than ploughing for poorly drained, unstable soils or high rainfall areas, restricted N availability and restricted crop choice. The success of conservation tillage in organic farming hinges on the choice of crop rotation to ensure weed and disease control and nitrogen availability. Rotation of tillage depth according to crop type, in conjunction with compaction control measures is also required. A high standard of management is required, tailored to local soil and site conditions. Innovative approaches for the application of conservation tillage, such as perennial mulches, mechanical control of cover crops, rotational tillage and controlled traffic, require further practical assessment.

Effects of Land Use and Management on SoilHydraulic Properties

“…Conservational tillage is one of the many tillage practices where at least 30% of the soil surface is covered by previous crop residue in order to conserve soil moisture and to reduce soil erosion [74]. In reduced tillage, the relative area covered by crop residue should be between 15 and 30%.…”

“…Conservation tillage compared to conventional tillage can lead to soil aggregate stability and improved soil structure due to concentrated soil organic matter near the soil surface [74]. The decomposing crop residue can reduce soil compaction and improve surface soil structure [79], further implying that soil physical properties can be directly related to the amount of organic matter present.…”

“…The typical cultivation depth in reduced tillage is 5-20 cm. When conventional tillage is employed, minimal crop residue, i.e., less than 15%, is left behind after harvest, and the tillage depth of approximately 20-35 cm [74] is produced by mechanical means such as plough. No-tillage or zero tillage is a technique where the soil cultivation is limited to the seedbed at the time of planting [75].…”

Organic Agriculture 3.0 is innovation with research

“…However, interest by organic farmers in conservation tillage is increasing in both arable (Peigné et al 2007;Peigné et al 2016) and vegetable cropping systems . Recent research projects (e.g.…”

Evaluation of soil structure using participatory methods in the semiarid region of Brazil

“…Although just the area 2 showed differences between MCS and NV (Table 2) this result outpoints a similarity between MCS and the reference situation (NV) in soil structure, which may be related to the (BERTOL et al, 2004;PEIGNÉ et al, 2007). Besides, a high earthworms activity was noted in these areas during the cropping season, which can be related to favourable effects on structural condition (MAHBOUBI; LAL, 1998).…”