Response to reviewers’ comments
Dear Editor,
We would like to re-submit our revised manuscript on “Influence of Macrofaunal Burrows on
Extracellular Enzyme Activity and Microbial Abundance in Subtropical Mangrove Sediments”
(No.: MECO-S-15-00376) for consideration of publication by Microbial Ecology. The
revision has been carried out based on the comments received from the two reviewers.
Detailed comments are as follows:
Reviewer 1
Q1. Methods. Replicates for different types? Sediment subsamples were pooled together to
form a composite sample for each type. So how many samples finally you included for
statistical analyses?
Reply: Thanks very much for your comment. Each type of sample contained 15 replicates
because the amounts of sediments sampled from each burrow were small. As for the
statistical analyses, only the composite samples (i.e., S, L, W, B) were used for the purpose of
compsrison.
Q2. Replicates for qPCR?
Repky: Three replicates were used for qPCR in this study. We have added this information in
the manuscript. Please see Lines 136-139. In addition, the gene copy number was also added
in Lines 185-187.
Q3. Language. Poor English. Long sentences in the abstract and other sections. Ambiguous
words, such as apparently, evidently, obviously, sometimes, directly suggest, indirectly
suggest, very little data. L195 were close to should be were closely related to.
Reoply: Thanks for your comment. We have tried our best to improve the quality of English
writing. Also, the ambiguous words were improved and changed to common and more
specific ones. The revised parts are highlighted in yellow color to distinguish from the
original ones.
Q4. Unclear results were shown in the abstract. For instance, "different extracellular enzyme
activities responded strongly to various environmental factors measured." But how repond?
"Alterations of bacterial and fungal abundance as well as fungi-to-bacteria ratio indirectly
suggested …" But what kind of alterations?
Reply: Abstract has been improved to show the specific and clear results. The revised parts
are highlighted in yellow color for distinction. Please see Lines 23-35.
Q5. L20-22. Delete details of the depth.
Reply: We have deleted the details of the depth.
Q6. L168. What difference?
Reply: We have specified the difference ‘significantly higher activity … than non-affected
sediments (i.e., Surface and Lower Layer).’ in Lines 173-174.
Q7. L221, pave the way to…?
Reply: We are sorry to use the improper phrase and have improved this sentence to make the
original intention more clear. Please see Line 228.
Reviewer 2
Q1. Abstract
Line 23-30: the conclusions should be more specific.
Reply: Thanks very much for your comments. We have improved the conclusions in the
abstract and highlighted in yellow color. Please see Lines 23-35.
Q2. Materials and Methods
Line 99: What the principle for the authors to select a depth of 5-6 cm for the lower layer?
why not select other depths? e.g. 15-20 cm.
Reply: We took the burrow wall sample about the depth of 5-6 cm, so we chose depth of 5-6
cm (about 5 cm away from burrow wall) accordingly to investigate the influence of crabs on
microbial abundance and enzyme activity.
Q3. Line 103-105: "Sediment subsamples were pooled together to form a composite sample",
How to set replicas?
Reply: Each type of sample contained 15 replicates because the amounts of sediments
sampled from each burrow wall were small and multiple samples had to accumulated to for a
composite sample of one type.
Q4. Line 133-134: Please provide the reference for primers Eub338 and Eub518.
Reply: This reference information has been added.
Q5. Results
Line 147: How about the Oxidation-Reduction Potential of different samples?
Reply: We measured the redox potential of each sample, and the descending trend was
Surface > Wall > Lower layer > Bottom (negative value). Since each subsample only had
very small amount of sediment and each sample type was formed by multiple subsamples.
There is apparent a question on the in-situ oxidation-reduction potential and the
representativeness of the composite sample due to pooling small subsamples to form. This is
largely due to the operation requirement for subsequent analyses. In the future study, we will
implement microanalysis in situ to obtain the environmental factor values to understand the
role of crabs on disturbing the sediment more accurately.
Q6. Discussion
Line 225: "crabs on the growth of microorganisms". Use "activity" to replace "growth".
Reply: The word “growth” has been replaced by “activity”.
The manuscript has been resubmitted to your journal. We are looking forward to your
response.