The contribution of trees and grasses to productivity of an Australian tropical savanna release_kcm7szbxdnhzdi2ugy6pejplui

by C. E. Moore, J. Beringer, B. Evans, L. B. Hutley, I. McHugh, N. J. Tapper

Published in Biogeosciences Discussions by Copernicus GmbH.

Volume 12, Issue 23 p19307-19350 (2015)


Savanna ecosystems cover 20 % of the global land surface and account for 25 % of global terrestrial carbon uptake. They support one fifth of the world's human population and are one of the most important ecosystems on our planet. Savanna productivity is a product of the interplay between trees and grass that co-dominate savanna landscapes and are maintained through interactions with climate and disturbance (fire, land use change, herbivory). In this study, we evaluate the temporally dynamic partitioning of overstory and understory carbon dioxide fluxes in Australian tropical savanna using overstory and understory eddy covariance measurements. Over a two year period (September 2012 to October 2014) the overall net ecosystem productivity (NEP) of the savanna was 506.2 (±22 SE) g C m<sup>−2</sup> yr<sup>−1</sup>. The total gross primary productivity (GPP) was 2267.1 (±80 SE) g C m<sup>−2</sup> yr<sup>−1</sup>, of which the understory contributed 32 %. The understory contribution was strongly seasonal, with most GPP occurring in the wet season (40 % of total ecosystem in the wet season and 18 % in the dry). This study is the first to elucidate the temporal dynamics of savanna understory and overstory carbon flux components explicitly using observational information. Understanding grass productivity is crucial for evaluating fuel loads, as is tree productivity for quantifying the tree carbon sink. This information will contribute to a significant refinement of the representation of savannas in models, as well as improved understanding of relative tree-grass productivity and competition for resources.
In application/xml+jats format

Archived Files and Locations

application/pdf  5.9 MB
file_i65imedx4vg5ljno4eowe3jsoa (web) (webarchive)
Read Archived PDF
Type  article-journal
Stage   published
Date   2015-12-07
Language   en ?
Container Metadata
Open Access Publication
Not in DOAJ
In Keepers Registery
ISSN-L:  1810-6285
Work Entity
access all versions, variants, and formats of this works (eg, pre-prints)
Catalog Record
Revision: 9db0c2cd-4052-4180-92bc-51ae226c899e