Abstract

Carbon (C) sequestration capacity in forest ecosystems is generally constrained by soil nitrogen (N) availability. Consequently, N fertilization is seen as a promising tool for enhancing ecosystem-level C sequestration in N-limited forests. We examined the responses of ecosystem C (vegetation and soil) and soil N dynamics to 3 years of annual nitrogen-phosphorus-potassium (N3P4K1 = 11.3 g N, 15.0 g P, 3.7 g K m(-2) year(-1)) or PK fertilization (P4K1), observed over 4 years in a 40-year-old Pinus densiflora forest with poor N nutrition in South Korea. PK fertilization without N was performed to test for PK limitation other than N. Neither tree growth nor soil C fluxes responded to annual NPK or PK fertilization despite an increase in soil mineral N fluxes following NPK fertilization. NPK fertilization increased the rate of N immobilization and 80% of the added N was recovered from mineral soil in the 0-5 cm layer, suggesting that relatively little of the added N was available to trees. These results indicate that N fertilization does not always enhance C sequestration even in forests with poor N nutrition and should therefore be applied with caution.

Published in

Scientific Reports
2023, Volume: 13, number: 1, article number: 1743

SLU Authors

• Lim, Hyungwoo

  • Department of Forest Ecology and Management, Swedish University of Agricultural Sciences
    
  • University of Tartu

UKÄ Subject classification

Environmental Sciences
Forest Science


Publication identifier

DOI: https://doi.org/10.1038/s41598-023-27989-3

Permanent link to this page (URI)

https://res.slu.se/id/publ/121593