Measuring Nitrate Leaching in the Vadose Zone of Loess Soils—Comparison of Batch Extraction and Centrifugation

Round 1

Reviewer 1 Report

Authors addressed an interesting topic that supply important information which help to non-point source pollution control. However, the manuscript was not well written and need a deep revision. These issues need to be addressed as following:

1.     Line 20, please concrete of data on reductions of ‘nitrate and chloride concentrations’. Also, supplemented data on other effects.

2.     In the Abstract, the mechanism of your findings should be supplemented.

3.     The conclusion of the Abstract was missing, and it should be supplemented.

4.     The novelty of this study is not clear. So, rewriting the Introduction is necessary.

5.     What is the design of the experiment?

6.     Observation methods should be more concentrate, so that other researchers cannot replicate yours experiment well. Moreover, the discrepancy of the results caused by years were not well discussed.

7.     All Tables and Figures should be revised as following: First, they must stand alone. Capital letters and lower case need to be explained clear. Second, stranded error and results of multiple comparisons should be supplemented. Third, weather conditions should be supplemented, at least shown as supplementary materials.

8.     The mechanism behand the Results is not clear. So, a deep discussion is essential to highlight your findings. Also, avoiding the Conclusions only repeating the sample Results.

In all, I suggest that the manuscript can be considered for publication in the Agronomy after a major revision.

There were too many grammar errors in the MS. This leads to low reading ability over the MS. the language of the manuscript should be checked and polished by a native English speaker or a professional researcher.

Author Response

Thanks for the review done. Please see the attachment for comments.

Author Response File: Author Response.docx

Reviewer 2 Report

The authors demonstrate how major ion [nitrate, chloride, ammonium, sulphate] quantification in soil (root-zone) leachate by means of batch experiments is impeded by anion exclusion effects. To properly account for such effects in practice, the authors propose empirically-derived correlations between batch-measured concentrations and their ‘true’ values (obtained from soil sample centrifugation). Once such ‘correction’ relationships have been established for the soil area of interest, one can keep using the batch technique (as a cheap and robust alternative to the more tedious procedure involving centrifugation).
The manuscript is well-composed, the methodology is described in sufficient detail, the results are presented clearly and they appear to largely support the claim that batch estimate errors can be satisfactorily ‘fixed’, in practice, by means of empirically-derived correlations of centrifugation-vs-batch measurements.

Author Response

Thanks for this review. No additions are needed.

Reviewer 3 Report

This study investigated nitrate leaching in the vadose zone of loess soils by comparison of batch extraction and centrifugation. The authors distilled the science out of simple questions and presented them for discussion and verification. The English is fluent, and readers can easily understand it. I think this article can be published after a minor revision.

The only shortcoming of this article is that the introduction section is too long. I suggest deleting some unnecessary background description to let the reader get to the topic of the article more quickly.

Author Response

Thanks for the review done. We shortened the introduction as requested from 1224 to 1077 words.

Reviewer 4 Report

I have thoroughly reviewed the manuscript, and I am pleased to say that it is well-written and ready for publication. The study addresses an important research question and provides valuable insights into the comparison of batch extraction and centrifugation methods for measuring nitrate concentrations in the vadose zone of loess soils. The manuscript meets the standards for publication in a scientific journal.

Author Response

Thanks for the review done. No revisions needed.

Round 2

Reviewer 1 Report

Athours responded well to Reviewer's comments!