The effect of repeated hurricanes on the age of organic carbon in humid tropical forest soil

© 2024 The Authors. Global Change Biology published by John Wiley & Sons Ltd..

Increasing hurricane frequency and intensity with climate change is likely to affect soil organic carbon (C) stocks in tropical forests. We examined the cycling of C between soil pools and with depth at the Luquillo Experimental Forest in Puerto Rico in soils over a 30-year period that spanned repeated hurricanes. We used a nonlinear matrix model of soil C pools and fluxes ("soilR") and constrained the parameters with soil and litter survey data. Soil chemistry and stable and radiocarbon isotopes were measured from three soil depths across a topographic gradient in 1988 and 2018. Our results suggest that pulses and subsequent reduction of inputs caused by severe hurricanes in 1989, 1998, and two in 2017 led to faster mean transit times of soil C in 0-10 cm and 35-60 cm depths relative to a modeled control soil with constant inputs over the 30-year period. Between 1988 and 2018, the occluded C stock increased and δ13C in all pools decreased, while changes in particulate and mineral-associated C were undetectable. The differences between 1988 and 2018 suggest that hurricane disturbance results in a dilution of the occluded light C pool with an influx of young, debris-deposited C, and possible microbial scavenging of old and young C in the particulate and mineral-associated pools. These effects led to a younger total soil C pool with faster mean transit times. Our results suggest that the increasing frequency of intense hurricanes will speed up rates of C cycling in tropical forests, making soil C more sensitive to future tropical forest stressors.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:30

Enthalten in:

Global change biology - 30(2024), 4 vom: 30. Apr., Seite e17265

Sprache:

Englisch

Beteiligte Personen:

Mayer, Allegra C [VerfasserIn]
McFarlane, Karis J [VerfasserIn]
Silver, Whendee L [VerfasserIn]

Links:

Volltext

Themen:

14C
7440-44-0
Carbon
Hurricane Hugo
Hurricane Maria
Journal Article
Luquillo Experimental Forest
Minerals
Radiocarbon
Soil
Soil carbon age
Transit times

Anmerkungen:

Date Completed 01.04.2024

Date Revised 01.04.2024

published: Print

Citation Status MEDLINE

doi:

10.1111/gcb.17265

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM370434609