Agricultural land potential for additional CO2 storage

Deforestation and intensive land use are major causes of climate change, according to a UN report published Thursday. Solutions such as eating more plant-based foods and addressing food waste are cited. But smart soil management is also part of the solution. Farmland can absorb more greenhouse gases if we manage it consciously, according to Dutch researchers and farmers.

Farmland can store more CO2 if 3 measures are taken:

1. conscious crop choice, including rotational crops
2. add soil conditioners on perennial grasslands
3. apply organic matter to fields

1: Conscious crop choice

Some crops hold a lot of carbon underground, such as legumes. Flexibility in switching should then be possible, of course

2: Soil improvers on perennial grasslands

Gerlinde De Deyn, professor of soil ecology at Wageningen University & Research reports to Nu.nl: "Clover is a very good natural soil improver because it can fix nitrogen from the air via its own root bacteria. Because carbon fixation also requires nitrogen fixation, both in plants and in the soil."

3: Application of organic matter to fields

Applying organic matter to fields, such as compost is a third option for increased CO2 sequestration in farmland. Manure mixed with straw or straw chopped with other crop residues all contains carbon. When that rots CO2 is released, if you make sure it ends up in the soil you store CO2. For a good carbon build-up and healthy soil it is sometimes important not to plow or to plow in a different way, for example shallow or without turning over the soil layer. Then the structure is preserved and with it a lot of soil life.

Trial in Beekdaelen

In Beekdaelen a farmer is being sought who wants to participate in a trial with better soil management, more biodiversity and less waterlogging. This will involve using less fertilizer and more compost. Soil treated with compost also allows rainwater better, resulting in less flooding during heavy rainfall.
Municipality of Beekdaelen supports the pilot financially and in doing so is in line with national and provincial policy to strive for circular agriculture. The municipality also wants to involve other rural municipalities in South Limburg in the pilot, as well as the Water Board, the Province of Limburg and LLTB.

Underground as important as above ground

To capture additional CO2, uptake and sequestration must exceed emissions. De Deyn: "It's actually very simple. You can't just harvest. You have to feed a soil to feed plants. As much carbon has to go in as out. Or even better: more. Unfortunately, that balance is missing in many places, and that's actually because we've started to focus on what's going on above the ground - the crops - and not what's going on below the ground. In other words, the soil, where the roots are. Organic matter contains all the elements that new plants need to grow again. But those must then first be made available by microorganisms." Carbon cycle and nitrogen cycle must come back into balance.

Better against drought and erosion

Good soil management also combats so-called land degradation. This is an important additional benefit, since the depletion of agricultural soils inhibits food production. Again, agricultural soils with additional carbon storage may be a solution. De Deyn: "Organic matter has a sponge effect. Soils can then stay moist longer during drought and, with deeper roots, are also more resistant to erosion."

Do you have experience with any of the above measures? Share them with Kiempunt editors so others can learn from your experiences: redactie@kiempunt-limburg.nl

Sources: Nu.nl, Limburger