Assessing the forest carbon budget for the state of Maine, USA: the importance of including lateral fluxes
Xinyuan Wei, University of Maine, xwei4@buffalo.edu (Presenter)
Daniel Hayes, University of Maine, daniel.j.hayes@maine.edu
Lateral carbon fluxes, including timber harvesting and terrestrial-aquatic dissolved organic carbon (DOC) loading, facilitate carbon relocation from forest ecosystems where it is sequestered from the atmosphere. Timber harvesting redistributes carbon stored in forest sectors to wood products pools of varying life cycles. Concurrently, a substantial volume of DOC is transported from forest soils to coastal oceans via inland water systems, thereby connecting terrestrial and marine carbon reservoirs. Consequently, incorporating lateral carbon fluxes into forest carbon budget assessments is crucial, as they have been identified as major contributors to discrepancies between top-down (atmospheric inversion models) and bottom-up (inventories and biosphere models) assessments at regional to global scales. In this study, we employed multiple estimators and models (i.e., Wood Products Carbon Storage Estimator, Terrestrial-aquatic DOC Fluxes model, and Coastal Particle Tracking model) to quantify the impact of timber harvesting and terrestrial-aquatic DOC flux on assessing forest carbon sequestration in Maine, USA, during 1990-2019. Our findings indicate that the wood products carbon pool accrued to 19.2 Tg C, with an annual increment rate of 0.64 Tg C per year. The model estimates suggest that the annual DOC loading from forested areas was 0.36 Tg C per year, with 0.08 Tg C per year and 0.01 Tg C per year buried in inland waters and marine sediments, respectively. Ultimately, 2.79 Tg C was sequestered in sediment over this time period, functioning as a long-term sink for atmospheric carbon. The total carbon sink (0.73 Tg C per year) attributed to these lateral carbon fluxes comprises 27% of the total carbon sink increment in live forest biomass in Maine (2.68 Tg C per year). Therefore, ignoring these lateral carbon fluxes would lead to underestimation of the forests' role in sequestering atmospheric carbon.
Poster: Poster_Wei_1-40_96_35.pdf
Associated Project(s):
Poster Location ID: 1-40
Presentation Type: Poster
Session: Poster Session 1
Session Date: Tue (May 9) 5:00-7:00 PM
CCE Program: TE