Conservation tillage and organic farming reduce soil erosion

Abstract

The impact of different arable farming practices on soil erosion is only partly resolved, and the effect of conservation tillage practices in organic agriculture on sediment loss has rarely been tested in the field. This study investigated rainfall-induced interrill sediment loss in a long-term replicated arable farming system and tillage experiment (the FAST trial) with four different cropping systems: (1) organic farming with intensive tillage, (2) organic farming with reduced tillage, (3) conventional farming with intensive tillage, and (4) conventional farming with no tillage. Measurements were carried out under simulated heavy rainfall events with runoff plots in 2014 (fallow land after winter wheat) and 2017 (during maize growth). Organic farming decreased mean sediment delivery compared to conventional farming by 30% (0.54 t ha −1 h −1). This study demonstrated that reduced tillage in organic farming decreased sediment delivery (0.73 t ha −1 h −1) compared to intensively tilled organic plots (1.87 t ha −1 h −1) by 61%. Nevertheless, the combination of conventional farming and no tillage showed the lowest sediment delivery (0.24 t ha −1 h −1), whereas intensively tilled conventional plots revealed the highest delivery (3.46 t ha −1 h −1). Erosion rates were much higher in June during maize growth (2.92 t ha −1 h −1) compared to those of fallow land after winter wheat (0.23 t ha −1 h −1). Soil surface cover and soil organic matter were the best predictors for reduced sediment delivery, and living plant cover from weeds in reduced organic treatments appeared to protect soil surfaces better than plant residues in conventional, no-tillage plots. Soil erosion rates were significantly lower when soil cover was above 30%. In conclusion, this study demonstrates that both organic farming and conservation agriculture reduce soil losses and showed for the first time that reduced tillage practices are a major improvement in organic farming when it comes to soil erosion control.

Twenty years of soil erosion on‐farm measurement: Annual variation, spatial distribution and the impact of conservation programmes for soil loss rates in Switzerland

“…They found that reduced erosion and reduced runoff after adoption of no‐till are widely observed. A minimum soil cover of 30% was often identified as a threshold for effective protection against soil erosion (Seitz et al, ; Skaalsveeen et al ., ). The definition of conservation tillage is therefore frequently coupled with at least 30% residue cover.…”

On-Site Water and Wind Erosion Experiments Reveal Relative Impact on Total Soil Erosion

“…This fact also offers a great opportunity in terms of resource protection, since a clever adaption to soil substrate and climatic factors can be considered a valuable option to adapt and mitigate the impact of climate change and to face socio-economic demands of a growing population. In particular, minimum to no-till options seem to prevent wind erosion as well as water erosion due to intact shallow crust or sealing, persisting crop residues and beneficial impact on soil organisms and soil structure [101,102].…”

Novel soil quality indicators for the evaluation of agricultural management practices: a biological perspective

“…Reduced tillage and addition of organic matter are widespread agricultural practices used to reduce the impact of soil management on soil properties and processes such as carbon cycling and soil structure formation and maintenance [8] , counteracting multiple soil threats such as soil organic matter depletion, soil erosion and compaction [57] . Across the ten European LTEs studied, the novel soil quality indicators were sensitive to changes brought about by these agricultural practices despite the large site effects of the LTEs.…”