Agricultural land potential for additional CO2 storage

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

Agricultural land can store more CO2 if 3 measures are taken:

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

1: Conscious crop choice

Some crops hold a lot of carbon underground, such as legumes.
This is also the case with green manures that farmers sometimes use as rotational crops.
Flexibility in crop rotation should then of course be possible

2: Soil improvers on perennial grasslands

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

3: Adding organic matter to fields

Applying organic matter to fields, such as compost, is a third possibility for more CO2 sequestration in agricultural land. Manure mixed with straw or straw chopped with other crop residues all contain 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 a healthy soil it is sometimes important not to plough or to plough in a different way, for instance shallowly or without turning the soil layer. Then the structure is retained and with it a lot of soil life.

Trial in Beekdaelen

In Beekdaelen is looking for a farmer who wants to participate in a trial with better soil management, more biodiversity and less flooding. This will involve using less artificial fertilizer and more compost. Soil treated with compost also lets better rainwater, so there is less water nuisance during heavy rainfall.
The municipality of Beekdaelen supports the pilot project financially and thus links up 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

In order to capture additional CO2, the uptake and sequestration must be greater than the emissions. De Deyn: "It's actually very simple. You can't just harvest. You have to feed a soil to feed plants. You have to get as much carbon in as out. Or even better: more. Unfortunately, that balance is lacking in many places, and that's actually because we've started to focus on what's going on above ground - the crops - and not on what's going on below ground. Or the soil, where the roots are. Organic matter contains all the elements that new plants need to grow again. But those must 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 counters so-called land degradation. This is an important additional benefit, because the depletion of agricultural land inhibits food production. Here, too, agricultural soils with additional carbon storage may be a solution. De Deyn: "Organic matter has a sponge effect. Soils can then stay moist for longer during droughts and, with deeper roots, are also more resistant to erosion."

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

Sources: Nu.nl, Limburger