Partitioning of forest floor CO2 emissions reveals the belowground interactions between different plant groups in a Scots pine stand in southern Finland

Changes in the climate may have unpredictable effects on belowground carbon processes and thus, balance of boreal forests. To understand interactions these soil to quantify potential changes cycle, partitioning forest floor respiration is crucial. For this purpose, we used nine different treatments separate sources dioxide (CO2) emissions a mature Scots pine (Pinus sylvestris L.) stand southern Finland. partition CO2 emissions, two trenching methods: 1) exclude roots mycorrhizal fungal mycelia (mesh with 1-µm pores) 2) roots, but not hyphae 50-µm pores). Additionally, 3) control treatment that included hyphae. from vegetation, removed it, left only dwarf shrubs, or vegetation intact. The were regularly measured flux chamber throughout growing seasons 2013–2015. total was partitioned into tree (contributing 48%), heterotrophic (30%) ground other than shrubs (10%), (8%), fungi (4%). Heterotrophic increased trenched without over time, due so-called ‘Gadgil effect’. In absence when hyphal access allowed, shrub experiment. This indicated had connections outside experimental plots via their ericoid mycorrhiza. At same such as mosses, suppressed treatments. Our results show competition intense between plant microbes.