Abstract

Westudiedcarbon and radiocarbon content in three historical time series of soil profiles from sites with different histories in the Parangalitsa biosphere, Rila mountains (Bulgaria).Our aim was to understand the consequences of forest regrowth in Eastern European forests for C stocks in the medium and long term.Disturbance history of the area has been studied in detail in recent decades, and we were therefore able to assess the impact of natural events such as windthrows and insect outbreaks on soil C stocks.By combining unique historical profile data with radiocarbon measurements, we obtained a picture of the kinetics at three different sites. These sites were 1) no land use change but an old (>120 years) forest subjected to decades old disturbances from the secondary consequences of a windthrow, 2) a forest site subjected to decades old disturbances from the direct consequences of a windthrow and 3) a grassland converted to forest.While the difference between direct and indirect disturbance did not have a relevant effect on C stocks, the ecological successions triggered either by afforestation or by disturbances caused similar dynamics of SOC decrease followed by accumulation, according to the pattern of primary productivity. The accumulation was marked in the conversion, and clearly involved the subsoil layers as well, leading to a C sequestration considered durable.The huge economic and social changes happening in Eastern Europe in the last two decades have generated a clear trend towards afforestation of lands that were formerly cultivated. The SOC changes from grassland to forest use in these areas (¿50tha-1) represented a doubling in stocks in less than 40years, and their impact on a global scale could represent an unexpected C sink.

Keywords

Forest SOC; Disturbance; Land-use change; C-14; Soil profile; Time series

Published in

Geoderma
2017, Volume: 297, pages: 19-27

SLU Authors

• Menichetti, Lorenzo

  • Department of Ecology, Swedish University of Agricultural Sciences
    
  • Agroscope

Sustainable Development Goals

SDG15 Protect, restore and promote sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, and halt and reverse land degradation and halt biodiversity loss


UKÄ Subject classification

Geosciences, Multidisciplinary
Forest Science
Environmental Sciences


Publication identifier

DOI: https://doi.org/10.1016/j.geoderma.2017.02.028

Permanent link to this page (URI)

https://res.slu.se/id/publ/80378