Grzyby ektomykoryzowe w obiegu węgla w ekosystemach leśnych

In boreal and temperate forests fungi play a particularly important role, since most trees form a symbiotic relationship with many species of ectomycorrhizal (ECM) fungi, providing them with assimilates in exchange for minerals. Mycorrhiza is considered one of the most significant factors affecting functioning of forest ecosystems, and in particular the processes of carbon cycling and storage. ECM fungi are involved both directly through carbon accumulation in the mycelial system, and indirectly through their influence on tree biomass production and organic matter decomposition. The amount of carbon transferred to ECM fungi usually varies from 10 to 25 or even 50% of the host's net photosynthesis, thus they are a group of organisms that significantly affect carbon flow into the soil. Most of that carbon is built into the mycelial system and its structures (fungal parts of ECM roots, extramatrical hyphae and rhizomorphs, sporocarps, etc.). Carbon allocation to the underground part of trees, and thus to ECM roots, changes with stand age and stand development phase. The biomass of active ECM roots and mycelium usually reaches its maximum in young stands, in the canopy closure phase; frequently, this is also true for the standing biomass of fruit bodies. A large share of ECM sporocarps in the forest carbon budget and high levels of ECM vegetative mycelium respiration are considered to be among the main pathways for the release of CO&sub2. from forest soil, indicating a significant role of ECM fungi in fast carbon flow via forest ecosystems. On the other hand, dead ECM fine roots and extramatrical mycelia are a very rich and important pool of sequestered carbon in the soil.