Please use this identifier to cite or link to this item: http://hdl.handle.net/10125/35284

Leaf litter decomposition rates increase with rising mean annual temperature in Hawaiian tropical montane wet forests

Item Summary

Title: Leaf litter decomposition rates increase with rising mean annual temperature in Hawaiian tropical montane wet forests
Authors: Bothwell, Lori D.
Selmants, Paul C.
Giardina, Christian P.
Litton, Creighton M.
Keywords: Ecology
Ecosystem Science
Environmental Science
Decomposition
Hawaii
show 7 moreTropical wet forest
Climate change
Elevation gradient
Nitrogen cycling
Metrosideros polymorpha
Mean annual temperature (MAT)
Leaf litter

show less
Issue Date: 04 Dec 2014
Publisher: PeerJ
Citation: Bothwell et al. (2014), Leaf litter decomposition rates increase with rising mean annual temperature in Hawaiian tropical montane wet forests. PeerJ 2:e685; DOI 10.7717/peerj.685
Related To: DOI 10.7717/peerj.685
Abstract: Decomposing litter in forest ecosystems supplies nutrients to plants, carbon to heterotrophic soil microorganisms and is a large source of CO2 to the atmosphere.
Despite its essential role in carbon and nutrient cycling, the temperature sensitivity
of leaf litter decay in tropical forest ecosystems remains poorly resolved, especially in
tropical montane wet forests where the warming trend may be amplified compared
to tropical wet forests at lower elevations. We quantified leaf litter decomposition
rates along a highly constrained 5.2 ◦C mean annual temperature (MAT) gradient in
tropical montane wet forests on the Island ofHawaii. Dominant vegetation, substrate
type and age, soil moisture, and disturbance history are all nearly constant across this
gradient, allowing us to isolate the effect of rising MAT on leaf litter decomposition
and nutrient release. Leaf litter decomposition rates were a positive linear function
of MAT, causing the residence time of leaf litter on the forest floor to decline by ∼31
days for each 1 ◦C increase in MAT. Our estimate of the Q10 temperature coefficient
for leaf litter decomposition was 2.17, within the commonly reported range
for heterotrophic organic matter decomposition (1.5–2.5) across a broad range of
ecosystems. The percentage of leaf litter nitrogen (N) remaining after six months
declined linearly with increasing MAT from ∼88% of initial N at the coolest site to
∼74% at the warmest site. The lack of net N immobilization during all three litter
collection periods at all MAT plots indicates that N was not limiting to leaf litter
decomposition, regardless of temperature. These results suggest that leaf litter decay
in tropical montane wet forests may be more sensitive to rising MAT than in tropical
lowland wet forests, and that increased rates of N release from decomposing litter
could delay or prevent progressive N limitation to net primary productivity with
climate warming.
Pages/Duration: 12 pages
URI/DOI: http://hdl.handle.net/10125/35284
Appears in Collections:CTAHR Faculty & Researcher Works
Litton, Creighton M.



Items in ScholarSpace are protected by copyright, with all rights reserved, unless otherwise indicated.