Elevated Concentrations of Carbon Dioxide (CO2) on the Harbechy Plateau (Moravian Karst) Reveal a Gas-Rich Soil Layer (GRSL)
Source abstract
Abstract
Precipitation leaches soil organic matter (SOM), transporting it downward where it accumulates at the soil–bedrock interface. Intensive agriculture, particularly tillage, accelerates this process. Microbial decomposition of SOM generates CO2, forming a gas-rich soil layer (GRSL)—a phenomenon long hypothesized but never directly confirmed until now. Drilling on the Harbechy Plateau (Moravian Karst) revealed a GRSL with a thickness of ~0.8 m, CO2 concentrations averaging 1.5–3 vol. % (peaks of 4–6 vol. %), and isotopic signatures (δ13C) indicating a mix of biogenic (−25‰) and atmospheric (−8‰) CO2. These findings necessitate re-evaluation of carbon cycling models in karst agroecosystems.
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Research context
OpenAlex topics: Geology and Paleoclimatology Research · Karst Systems and Hydrogeology · Soil Carbon and Nitrogen Dynamics
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Department of Geological Sciences, Faculty of Science, Masaryk University, Kotlářská 267/2, 61137 Brno, Czech Republic
Czech Geological Survey, Leitnerova 22, 65869 Brno, Czech Republic
Czech Geological Survey, Klárov 131/3, 11821 Praha 1, Czech Republic
Department of Biology, Faculty of Education, Masaryk University, Poříčí 623/7, 60300 Brno, Czech Republic
Institute of Geonics, Academy of Sciences of the Czech Republic, Studentská 1768/9, 70800 Ostrava-Poruba, Czech Republic
Nature Conservation Agency of the Czech Republic, Svitavská 29, 67801 Blansko, Czech Republic
Funding
Technology Agency of the Czech Republic · not applicableCzech Geological Survey
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