Do mycorrhizal symbionts drive latitudinal trends in photosynthetic carbon use efficiency and carbon sequestration in boreal forests?

• DOI: 10.1016/j.foreco.2022.120355
• Publication Date: 2022-06-22T17:10:39Z
• Authors: Annikki Mäkelä; Xianglin Tian; Anna Repo; Hannu Ilvesniemi; John Marshall; Francesco Minunno; Torgny Näsholm; Pauliina Schiestl...; Aleksi Lehtonen
• Keywords: Soil carbon; Carbon fibers; Ectomycorrhiza; Litter; Boreal ecosystem

There is evidence that carbon fluxes and stocks decrease with increasing latitude in boreal forests, suggesting a reduction use efficiency. While vegetation soil dynamics have been widely studied, the empirical finding ectomycorrhizal fungi (ECM) become more abundant towards north has not quantitatively linked to We formulated conceptual model of combined fine-root ECM efficiency (CUE) as NPP/GPP (net primary production/gross production). For this, we included mycorrhiza gains plant NPP but considered extramatrical hyphae well exudates losses. quantified processes across latitudinal gradient using published eco-physiological morphological measurements from coniferous forests. In parallel, developed two CUE models large-scale amended established models. All predicted similar trends net ecosystem production (NEP). declined on average by 0.1 60 70 overall mean 0.390 ± 0.037. NEP 200 g m−2 yr−1 171 79.4 yr−1. had no significant effect carbon. Our findings suggest can proportion assimilated hence be an important driver decline at higher latitudes. suggests quantitative contribution less any possible implications through litter quality remain assessed. The approach provides simple proxy for regional C budget estimates.