Soil trace gas fluxes along orthogonal precipitation and soil fertility gradients in tropical lowland forests of Panama

Matson, Amanda L.; Corre, Marife D.; Langs, Kerstin; Veldkamp, Edzo

doi:https://doi.org/10.5194/bg-14-3509-2017

Articles | Volume 14, issue 14

https://doi.org/10.5194/bg-14-3509-2017

© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.

https://doi.org/10.5194/bg-14-3509-2017

© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.

Articles | Volume 14, issue 14

Research article

|

26 Jul 2017

Research article |

| 26 Jul 2017

Soil trace gas fluxes along orthogonal precipitation and soil fertility gradients in tropical lowland forests of Panama

Amanda L. Matson, Marife D. Corre, Kerstin Langs, and Edzo Veldkamp

Download

Final revised paper (published on 26 Jul 2017)
Supplement to the final revised paper
Preprint (discussion started on 24 Nov 2016)
Supplement to the preprint

Interactive discussion

Status: closed

AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment

- Printer-friendly version

- Supplement

RC1: 'RC: BG-2016-393', Anonymous Referee #2, 25 Jan 2017
RC2: 'Review of "Soil trace gas fluxes..." by Matson et al.', Yit Arn Teh, 27 Jan 2017
AC1: 'Response to reviewers', Amanda Matson, 09 Mar 2017

Peer-review completion

AR: Author's response | RR: Referee report | ED: Editor decision

ED: Reconsider after major revisions (17 Mar 2017) by Ivonne Trebs

AR by Amanda Matson on behalf of the Authors (28 Apr 2017) Author's response Manuscript

ED: Referee Nomination & Report Request started (02 May 2017) by Ivonne Trebs

RR by Yit Arn Teh (18 May 2017)

RR by Anonymous Referee #2 (22 May 2017)

Suggestions for revision or reasons for rejection

The revision of bg-2016-393 improved the manuscript a lot. Especially the linear mixed effects models better highlight the importance of the different environmental factors to the fluxes. However, there are still some points which are not yet clear.

(1) There is no doubt, that the rainfall shows a "parabolic pattern", however, after showing the individual datapoints in fig.3 the former point cloud now shows linear declines of CO2 flux for each site. Therefore, I assume that the autors mean by "parabolic pattern" a maximum CO2 flux which is limited by a parabolic function? If that is the case, I recommend that the authors include a parabolic function into Fig. 3 and better describe what "parabolic pattern" actually means to them. Otherwise, I recommend to discuss the linear decline with existing literature, Skopp et al. 1990.

(2) My intention was not to motivate the autors for including a sentence about using microbial abundance and activity in future studies, but rather to discuss their findings in a better context to microbial processes. As I learned from the replies to R1, there is another paper on its way which might deal with that topic? However, also this paper would highly benefit if the coupling of CH4 and N2O fluxes would be discussed. I agree that denitrification is not making sense. However, especially in the dry season when CH4 uptake is dominant and soils are more oxic, also denitrification should be decreased. Since methanotrophs are also known to produce N2O, the decrease of N2O caused by denitrification might be larger than the increase of N2O caused by methanotrophy and therefore no clear correlation between CH4 and N2O is obtained.

I agree that the ambient NO mixing ratio is not the right one to use in a scatter plot, however, I would use the NO mixing ratio shortly before reopening the chamber. Also I think it might be worth to include a statement about potential effects of a variable NO background (before closing and after opening the chamber) on the NO flux measured in between.

Hide

ED: Publish subject to minor revisions (Editor review) (24 May 2017) by Ivonne Trebs

AR by Amanda Matson on behalf of the Authors (07 Jun 2017) Author's response Manuscript

ED: Publish as is (09 Jun 2017) by Ivonne Trebs

AR by Amanda Matson on behalf of the Authors (18 Jun 2017)

Download

Article (8104 KB)
Full-text XML

Short summary

We present 1 to 2 years of greenhouse gas flux field measurements (CO₂, CH₄, N₂O and NO) in the tropical forest soils of Panama. Fluxes were measured in five sites along the orthogonal gradients of precipitation and fertility. Using these natural gradients, our results highlight the importance of both short-term (climate) and long-term (soil and site characteristics) factors in predicting soil trace gas fluxes and provide information for modeling trace gases under future climate scenarios.