2017-01-23T15:46:12 q108

Soil-atmosphere exchange of CO2, CH4 and N2O over two consecutive years from a subtropical rainforest in South-Eastern Queensland

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Soil-atmosphere exchange of CO2, CH4 and N2O was measured over two consecutive years from a subtropical rainforest in South-Eastern Queensland, Australia using an automated sampling system. Interannual variation in fluxes of all gases over the 2 years was minimal despite large discrepancies in rainfall, while a pronounced seasonal variation could only be observed for CO2 fluxes. High infiltration, drainage and subsequent high soil aeration under the rainforest limited N2O loss while promoting substantial CH4 uptake. The average annual N2O loss of 0.5 ± 0.1 kg N2O-N ha-1 over the two year measurement period was at the lower end of reported fluxes from rainforest soils. The rainforest soil functioned as a sink for atmospheric CH4 throughout the entire two year period despite periods of substantial rainfall. A clear linear correlation between soil moisture and CH4 uptake was found. Rates of uptake ranged from greater than 15 g CH4-C ha-1 day-1 during extended dry periods to less than 2-5 g CH4-C ha-1 day-1 when soil water content was high. The calculated annual CH4 uptake at the site was 3.65 kg CH4-C ha-1 year-1. This is amongst the highest reported for rainforest systems, reiterating the ability of aerated subtropical rainforests to act as substantial sinks of CH4. A spatial study involving 30 manual chambers distributed across three remnant rainforest sites with similar vegetation and climatic conditions showed N2O fluxes almost 8 times higher and CH4 uptake reduced by over one third as clay content of the rainforest soil increased from 12% to 23%. An exponential relationship was found between N2O flux and percent clay content (r2 = 0.57) across the 30 chambers. This demonstrates that for some rainforest ecosystems soil texture and related water infiltration and WFPS constraints may play a more important role in controlling fluxes than either vegetation or seasonal variability.

Access rights

Terms of use for the data to be determined through negotiation with the primary contact. To arrange access to this data contact the primary contact.

Geographical area of data collection

text
Mooloolah, Queensland, Australia
iso19139dcmiBox
northlimit=-26.694600; southlimit=-26.853205; westlimit=152.854075; eastLimit=153.155041; projection=WGS84

Publications

Rowlings, David, Grace, Peter, Kiese, Ralf, & Scheer, Clemens (2010) Quantifying N2O and CO2 emissions from subtropical pasture. In Gilkes, R & Prakongkep, N (Eds.) Soil Solutions for a Changing World: proceedings of the 19th World Congress of Soil Science, 1 - 6 August 2010, Australia, Queensland, Brisbane. http://eprints.qut.edu.au/37655/

Research areas

Earth sciences
Geochemistry
soil texture
Atmospheric sciences
N2O
subtropical gallery rainforest
CO2
CH4

Cite this collection

Rowlings, D. (2009). Mooloolah_Rainforest_2007_09. Institute for Sustainable Resources, Queensland University of Technology. Rowlings.22.1 http://n2o.org.au/knb/metacat/Rowlings.22.1/default
Rowlings,David. (2010): Soil-atmosphere exchange of CO2, CH4 and N2O over two consecutive years from a subtropical rainforest in South-Eastern Queensland. [Queensland University of Technology]. https://doi.org/10.4225/09/5885980eeae59

Copyright

©

Dates of data collection

From 2007-03-01 to 2009-03-28

Connections

Has association with
David Rowlings  (Researcher)
Peter Grace  (Researcher)
Is supported by
Metacat  (Equipment)

Contacts

Name: David Rowlings

Other

Date record created:
2010-12-06T13:31:04Z
Date record modified:
2017-01-23T15:46:12
Record status:
Published - Open Access