Practice Abstract - Research and innovation

Soil CO2 emission monitoring

Hungary

Soil processes are largely invisible, making it difficult for farmers to assess whether sustainable practices improve soil health. Within the trans4num project, soil CO₂ emission monitoring was tested as a practical tool to evaluate the effects of nature-based solutions (NBS) on soil biological activity, nutrient cycling and carbon efficiency. Combined with soil, plant and drone monitoring, CO₂ measurements help farmers make more informed decisions and better understand how management practices influence long-term soil resilience.

The need

Many soil degradation processes develop gradually and remain unnoticed until crop performance declines. Reduced biological activity, poor soil structure, lower water retention and inefficient nutrient cycling cannot easily be detected through visual observation alone. Farmers therefore need practical monitoring tools that provide early information on soil functioning and help evaluate whether NBS deliver environmental benefits. These challenges are particularly relevant in Hungary's Szigetköz region, where agricultural production is affected by changing groundwater conditions, drought risk and strong natural soil variability.

The benefits

Soil CO₂ monitoring:

  • Makes below-ground biological activity visible.
  • Assesses whether NBS improve soil functioning.
  • Supports more precise nutrient management.
  • Links climate mitigation with everyday farm management.
  • Identifies spatial and temporal variability within fields.
  • Strengthens advisory services, demonstration activities and farmer learning.
  • Supports long-term monitoring of regenerative agricultural practices.

Additional information

trans4num solution

Within the trans4num project, soil CO₂ emission monitoring was integrated into a nature-based farming system tested in Kimle, Hungary, comparing NBS with conventional management across a three-year rotation of durum wheat, sorghum and soybean. The NBS system combined crop rotation, no-tillage, reduced herbicide and pesticide use, poultry manure pellets, biostimulants, winter cover crops and continuous crop and soil monitoring.

CO₂ emissions were measured using a portable closed-chamber system alongside soil sampling, plant nutrient analyses, soil profile observations, drone monitoring and satellite imagery. Because a single CO₂ value cannot determine whether soil is gaining or losing carbon, all measurements were interpreted together.

Across all three crops, NBS consistently produced equal or lower CO₂ emissions per unit of harvested yield than conventional systems, with significant reductions for sorghum and durum wheat. Carbon efficiency improved while maintaining comparable yields, demonstrating the climate mitigation potential of NBS. Long-term monitoring also showed gradual improvements in soil organic carbon, organic matter, nitrogen cycling and biological activity, particularly within the upper 0–30 cm of soil.

Challenges / limitations

CO₂ emissions vary with season, temperature, soil moisture and recent field operations. Natural field variability can mask treatment effects, making repeated, long-term measurements essential.

Resources needed

Implementation requires portable CO₂ sensors, closed-chamber systems, soil moisture and temperature measurements, drone and satellite monitoring, farmer training, advisory support and consistent multi-year monitoring protocols.

Practical recommendations

Measure CO₂ repeatedly during the growing season, record weather and management conditions, compare treatments under similar conditions, & always interpret CO₂ measurements together with soil, plant and remote-sensing data rather than as a stand-alone indicator.

Source Project
Transformation for sustainable nutrient supply and management
Ongoing | 2022-2026
Main funding source
Horizon Europe (EU Research and Innovation Programme)
Geographical location
Denmark, Germany, Hungary, Netherlands, Romania, Switzerland, The United Kingdom, China
Project details

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