The information below comes from a project called SmartSOIL. This project is a European wide project aimed at looking at sustainable farm management that will reduce the threats from climate change. It looks to reverse the current degradation trend of European Agricultural Soils by improving soil carbon management in European arable and mixed farming systems. To read more about the project please click here.
What soil organic carbon measures are the most cost –effective?
Research conducted through the Smart-SOIL project looked at the cost effectiveness of implementing management to improve soil carbon stocks across 6 case study regions. The regions involved in the study are:
- Zealand, Denmark
- Central Region, Hungary
- Tuscany, Italy
- Mazovia, Poland
- East Coast, Scotland
- Andalucia, Spain
Cost effectiveness of the measures was assessed in terms of the impact on the typical gross margin per crop. The results indicated that in each of the case study regions, there was potential for the uptake of measures that produced benefits to the farmer’s bottom line and the soil organic carbon levels.
Measures were grouped into three broad categories.
Reduced input costs: Measures such as minimum tillage and the use of manures are estimated to be highly cost-effective event where modest reductions in yield occur because of the potential to reduce input costs. These input costs include:
The fuel and time required for cultivation relative to conventional tillage and reduced mineral fertiliser costs (manures)
Zero tillage performs less well as there is a cost incurred for increased cost protection spraying. The inclusion of legumes in the rotation also appears to be cost effective due to the reduced need for mineral fertiliser input; however, our analysis does not consider impacts over the course of a rotation.
Loss of revenue from by-products – Residue management has a high potential for soil organic carbon increase in most case study regions, but this could only be achieved at a loss of revenue from selling straw as a by-product.
Increased input costs. Under assumptions of unchanged or reduced yield impacts, cover crops were estimated to result in a large reduction in gross margin due to the additional costs or seeds and cultivation. But where yield was assumed to increase the cost-effectiveness improved for some crops in some regions. This highlights the potential role for good agronomic advice to ensure that the benefits of SOC measures can be fully realised.
A significant barrier to implementing soil carbon management is that most farm production related decisions are taken in the short-term, whereas managing soil carbon effectively needs a long term approach. Key barriers to uptake of practices include: perceived difficulty in demonstrating the positive effects of soil carbon management practices and economic benefits over a long time scale; and advisers being unable to provide suitable advice due to inadequate information or training. Most farmers were unconvinced of the economic benefits of practices for managing soil carbon. Incentives are therefore needed either as subsidies or as evidence of the cost effectiveness of practices.
Real life case study
Rafael Alonso Aguilera runs the family owned Oro del Desierto farm in Andalucia in Spain. It is a 650ha organic mixed farm with 110ha olive groves, cereals, vineyards and pasture for livestock (irrigated systems). He has loam, sandy-loam and sandy soils but manages to avoid soil erosion problems and water shortages common in the area due to managing the organic matter in the soil using minimum tillage, gutters or infiltration canals; terraces, control furrows, cover crops, inert cover (mulch) and adding organic matter (their own compost).
Rafael comments “We have analysed our soils and we have recorded that the soil organic matter is increasing compared to the beginning. We realise that leaving the pruning debris and grass and the applications of composts have largely contributed to an increase in the soil organic matter and in turn soil fertility. Thanks to these practices, the soil water retention is much better, erosion is reduced and the soil biology populations are larger. You can obtain many advantages from sustainable management.”
Why not check out our soil carbon pages for more inspiration?