Carbon and nutrient pools and fluxes in unmanaged mountain Norway spruce forests, and losses after natural tree dieback

0583771 - BC 2024 RIV NL eng J - Journal Article
Kopáček, Jiří - Bače, R. - Choma, M. - Hejzlar, Josef - Kaňa, Jiří - Oulehle, F. - Porcal, Petr - Svoboda, M. - Tahovská, K.
Carbon and nutrient pools and fluxes in unmanaged mountain Norway spruce forests, and losses after natural tree dieback.
Science of the Total Environment. Roč. 903, Aug (2023), č. článku 166233. ISSN 0048-9697. E-ISSN 1879-1026
R&D Projects: GA ČR GA22-05421S; GA TA ČR(CZ) TO01000220
Institutional support: RVO:60077344
Keywords : coarse woody debris * water chemistry * atmospheric deposition * dry deposition * pine-beetle * Bark beetle * Base cations
OECD category: Marine biology, freshwater biology, limnology
Impact factor: 9.8, year: 2022
Method of publishing: Open access
https://doi.org/10.1016/j.scitotenv.2023.166233

Forest areas infected by insects are increasing in Europe and North America due to accelerating climate change. A 2000-2020 mass budget study on major elements (C, N, P, Ca, Mg, K) in the atmosphere-plant-soil-water systems of two unmanaged catchments enabled us to evaluate changes in pools and fluxes related to tree dieback and long-term accumulation/losses during the post-glacial period. A bark-beetle outbreak killed >75% of all trees in a mature mountain spruce forest in one catchment and all dead biomass was left on site. A similar forest in a nearby catchment was only marginally affected. We observed that: (1) the long-term (millennial) C and N accumulation in soils averaged 10-22 and 0.5-1.1kgha(-1)yr(-1), respectively, while losses of Ca, Mg, and K from soils ranged from 0.1 to 2.6kgha(-1)yr(-1). (2) Only <0.8% and <1.5% of the respective total C and N fluxes entering the soil annually from vegetation were permanently stored in soils. (3) The post-disturbance decomposition of dead tree biomass reduced vegetation element pools from 27% (C) to 73% (P) between 2004 and 2019. (4) Tree dieback decreased net atmospheric element inputs to the impacted catchment, and increased theleachingof all elements and gaseous losses of C (similar to 2.3tha(-1)yr(-1)) and N (similar to 14kgha(-1)yr(-1)). The disturbed catchment became a net C source, but similar to 50% of the N released from dead biomass accumulated in soils. (5) Despite the severe forest disturbance, the dissolved losses of Ca and Mg represented 52-58% of their leaching from intact stands during the peaking atmospheric acidification from 1970 to 1990. (6) Disturbance-related net leaching of P, Ca, Mg, and K were 4, 69, 16, and 114kgha(-1), respectively, which represented 7-38% of the losses potentially related to sanitary logging and subsequent removal of the aboveground tree biomass.
Permanent Link: https://hdl.handle.net/11104/0351770