Drainage Ditch Cleaning Has No Impact on the Carbon and Greenhouse Gas Balances in a Recent Forest Clear-Cut in Boreal Sweden

Round 1

Reviewer 1 Report

This study investigated the effect of ditch cleaning (DC) on the GHG emission in boreal Sweden. The result founds that although the DC had lowered the water table level and decrease the soil moisture, but had little effect on the net CO2 exchange and its component fluxes, GPP and Reco. The manuscript is organized in proper style. The method and result are presented with adequate and believable information. Here are only few minor suggestions for the method:

1. Figure 1, for the red sampling site (cleaned site), the solid points indicate the 40 m distance form the ditch. How about the distance of the solid point to the ditch which intersect with target ditch? Is the distance less than 40 m?

2. line 157, although the studied system was forest, the chamber was covered on herbaceous vegetation. So, what’s the dominant herbaceous species in the frame?

3. line 122: replace the “25.1 ± 5.3 and 0.84 ± 0.19 %” with  “25.1 ± 5.3% and 0.84 ± 0.19%”, and modify the similar style throughout the text.

Author Response

We thank the reviewer for insightful comments and constructive feedback. We believe that these have helped us to considerably improve this manuscript. Our detailed responses to each comment follows below in bold font. Please note that the line numbers refer to the clean version of our revised manuscript.

1. Figure 1, for the red sampling site (cleaned site), the solid points indicate the 40 m distance form the ditch. How about the distance of the solid point to the ditch which intersect with target ditch? Is the distance less than 40 m?

Some 40m plots were located at similar distance to both the main ditch and surrounding ditches, but there was a 2m variation from 40m when identifying flat locations for frame installations. For instance, the red 40m plot at the southwest was about 38m from the intersecting ditch and 42m from the main ditch.  To clarify this, we have further added more information into the manuscript as below:

“The experimental design included two parallel transects (about 30 m apart) in each of the two treatment areas with sampling plots at three distances (4, 20, and 40 m) on both sides of the ditch along each transect (i.e. 2 treatment areas × 2 transects × 3 distances × 2 sides = 24 plots) (Figure 2). The 40 m plots were also at similar distance to the surrounding intersecting ditches (Figure 2).” (Line 131-135)

2. line 157, although the studied system was forest, the chamber was covered on herbaceous vegetation. So, what’s the dominant herbaceous species in the frame?

The herbaceous species in the frame were consistent with the surrounding area mentioned in section 2.1. To clarify this, we have now added another sentence as follows: “The observed vegetation species and coverage within the frames were consistent with the surrounding area indicated in section 2.1 over the study years. (Line 150-151)”.

3. line 122: replace the “25.1 ± 5.3 and 0.84 ± 0.19 %” with  “25.1 ± 5.3% and 0.84 ± 0.19%”, and modify the similar style throughout the text. 

The styles have now been corrected in the revision. We have also gone through the entire manuscript and made according changes.

Reviewer 2 Report

Dear authors,

Thank you for the opportunity to read the research results (Drainage ditch cleaning has no impact on the carbon and greenhouse gas balances in a recent forest clear-cut in boreal Sweden). The study is a well-crafted and well-worked one.

Because the working methodology was a complex one, I suggest introducing of a flowchart at the beginning of this chapter. This could make the methodological flow easier to follow.

 

Sincerely,

 

Author Response

We thank the reviewer for the insightful suggestions. A flowchart has now been included as Figure 1 in the revised manuscript. We also believe that the revision with the flowchart could improve the readability and considerably improve this manuscript. For your easy reference, the figure is also included in the attachment.

Author Response File: Author Response.docx