the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
| 29 Jan 2026
Non-inversion tillage benefits soil N retention during bare soil period coinciding with wet spell
Abstract. Recent meta-analyses suggest risks of increased nitrate leaching with the implementation of reduced tillage practices. This study aimed to quantify effects of a subsidized and commonly implemented form of non-inversion tillage in Switzerland (NIT, i.e. chisel ploughing) in comparison to conventional tillage (CT, i.e. mouldboard ploughing) on nitrate leaching and its driving processes (i.e. water fluxes, soil temperature, plant uptake). A lysimeter experiment was conducted at the lysimeter facility Reckenholz/Zurich in Switzerland, mimicking tillage differences. Results after three years of treatment implementation show that during the following three years, cumulative nitrate leaching was 26 % higher under CT than under NIT (i.e. 63 ± 10 kg/ha N with CT vs. 46 ± 9 kg/ha N with NIT). The observed effect was driven by differences in nitrate concentrations in seepage water rather than seepage water amounts. The beneficial effect of NIT on nitrate leaching was most pronounced during and shortly after a bare soil period following sugar beet cultivation, which coincided with above-average spring precipitation. These findings suggest that reduced soil management may hold the potential to reduce nitrate leaching during winter and spring wet spells with poor plant cover, which are expected to become more frequent with progressing climate change.
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Notice on discussion status
The requested preprint has a corresponding peer-reviewed final revised paper. You are encouraged to refer to the final revised version.
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Preprint
(2287 KB)
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The requested preprint has a corresponding peer-reviewed final revised paper. You are encouraged to refer to the final revised version.
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- Final revised paper
Journal article(s) based on this preprint
Reduced tillage lowered nitrate leaching by up to 42 percent in some soils during a very rainy period without crop cover. The results suggest that reduced soil management could help protect water quality under future climate conditions with wetter winter and spring conditions.
Interactive discussion
Status: closed
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RC1: 'Comment on egusphere-2026-330', Abel Veloso, 23 Feb 2026
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AC1: 'Reply on RC1', Annelie Holzkämper, 20 Apr 2026
The comment was uploaded in the form of a supplement: https://egusphere.copernicus.org/preprints/2026/egusphere-2026-330/egusphere-2026-330-AC1-supplement.pdf
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AC1: 'Reply on RC1', Annelie Holzkämper, 20 Apr 2026
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RC2: 'Comment on egusphere-2026-330', Anonymous Referee #2, 26 Mar 2026
The manuscript presents lysimeter results comparing conventional tillage (CT) and no‑inversion tillage (NIT) across three soil types under the same crop rotations over a 2–3 year period (2013–2016). The topic is timely, and the results clearly indicate differences in nitrogen losses between CT and NIT. That said, the manuscript would benefit from substantial revisions to improve clarity, structure, and the strength of its mechanistic interpretation.
In several places, the writing reads as a sequence of observations rather than a cohesive argument that explicitly links proposed mechanisms to the reported patterns. In addition, key pieces of evidence are sometimes introduced late in paragraphs, where readers would instead expect a clear synthesis or “take‑home” message for the section.
Relatedly, the manuscript includes considerable discussion of carbon’s role in mediating nitrogen loss under different tillage practices, but it is not clear that carbon content was directly measured in the study soils. The contribution could be strengthened considerably by incorporating additional measurements—such as soil carbon quantity and forms of nitrogen (and, ideally, complementary water chemistry where feasible)—to better support the claims about nitrogen retention and the drivers of observed losses.
At present, I think the manuscript requires major revision before it can be considered for publication. While the dataset is interesting and potentially valuable, the current presentation feels closer to a field report of patterns than a study that systematically evaluates multiple factors shaping nitrogen dynamics. Several important variables (e.g., carbon content, aggregate stability, nitrogen species, litter quantity/quality, rooting depth, and the impacts of plowing) are discussed as likely explanations but do not appear to be directly measured, aside from porosity. Where porosity is reported (notably in the appendix), it would also help to clearly indicate which values correspond to each treatment (NIT vs. CT), and to ensure those results are integrated into the main narrative as appropriate.
Finally, the manuscript would benefit from careful attention to consistency in figures and text, including standardized styling (colors and formatting) and consistent treatment labeling/abbreviations throughout.
Overall, I see real promise in this work, particularly in highlighting management differences and the importance of site context. To make the manuscript publication‑ready, I encourage the authors to (1) strengthen the linkage between mechanisms and observations in the writing, (2) add or more directly incorporate key supporting data (especially soil nitrogen, and carbon if central to the interpretation), and (3) more fully integrate relevant supplemental information (for example, the temperature data) into the analysis and discussion.
Lines 35-40: I think it would strengthen the authors argument if you can add a line about how widespread these tillage practices are (i.e. what proportion of farms or what percent of land undergoes method X or Y via management). This would strengthen your paper’s relevance and impact.
Graphical abstract: It currently does not suggest based on the drawing that one method goes deeper than the other. Furthermore, the abstract doesn’t show contrast with regards to changes to soil structure which appear to be central in the author’s argument.
Line 42: N2O should be subscript (similar for all other chemical formulas brought into the text and used in your graphs/figures, use correct notation and subscript!). The sentence after this makes no substantial addition to the introduction nor does it connect to the next paragraph. Reconsider structure here.
Line 49: “addressed the inconsistency in the impacts of tillage on nitrate leaching currently documented.” Or rewrite another way, its very awkwardly phrased at the moment.
Line 51: This last sentence does not connect well with the next paragraph nor is it a good concluding sentence.
Line 53: Why is this sentence separate from everything else?
Line 55: This is not a complete paragraph. Plant uptake is something that could decrease the amount of leachate correct? Then this wouldn’t be a driver but instead a factor that affects the magnitude of nitrate leachate. In this case calling these “processes that influence nitrate leaching dynamics” would be more accurate.
Line 79: Any time you place the variable from your equation into your main text, keep the same text style as the one you used in the equation description (is it subscript a or normal a?).
Line 95-97: this is exactly why you need to have a section in the introduction that can speak to how widely used this practice is globally. It enhances your research’s relevance to global community while emphasizing its importance and makes sure content like this is already introduced so that it doesn’t take up space later in the manuscript where you need to focus on the experimental details instead.
Line 105: Did each treatment receive the same cover crop treatment? It would be helpful to have a schematic here of the experimental design or a table in the SI.
Line 115: The listing of the cover crop rotations is confusing with some have a (+) and others not having this. Improve the clarity of what you are trying to express here. Is there a particular order (numbering may be better). Is there a set duo? (note this in the text). At the moment this listing is somewhat disorienting and difficult to parse. Additionally, italize scientific names.
Line 120: These values should be supplied in the SI or some note on using these to normalize your results should be made (or if they weren’t that different from each other between the treatments, this should be noted).
Line 125: Be consistent throughout your text with regards on how you will be referring to your nitrogen species (chemical formula? Written name? Also if you choose chemical formula add respective charges and subscripts – be consistent!).
Figure 1 & similar style comments for figure 2
Where is the key for the first top figure? (monthly precip and mean temp)
Label these figures as Fig 1a 1b 1c etc same for figure 2
Figure axes labels are blurry and so is a few of the graphs included here (fix please!)
Label evapotranspiration as evapotranspiration.
Monthly precipitation data is provided in Month:Year format and the following figures that are meant to be aligned over the same time periods as this precip data has Year:Month:Day. Change these to have the same formatting or change these to all be over one axes if appropriate (which I believe it is).
I would further suggest placing the name of the crop that was collected over the top of the colored boxes.
Be consistent in all of your graph labelling – will you capitalize or not? Don’t short hand write the labels, use full words to convey what you are showing and explain in detail the units in the captions if necessary.
Line 185: reformat the figure caption:
coloured background shading is in reference to cropping periods: purple (phacelia), yellow (sugar beet) … ; grey dashed vertical lines denote ploughing times; …etc
Get rid of the “=” they are hard to read/decipher with everything else that’s being listed in this caption.
For figure 2 make one large legend for parts b, c, d (label these figures accordingly)Figure 3 should be colored to match earlier graphs. However, choose a color palette that is color blind safe. Also denote significant differences on your figure in some manner (asterisks or letters).
Line 205: Your mechanistic connection here between pore structure and matrix water flow is not very clear. Are you saying that increased tillage under CT would reduce pore connectivity or increase pore presence? What about pore structure is facilitating the matrix water flow in CT vs NIT. You leave your readers without a clear connection between the two and then just citing various literature that suggest similar trends. It will really help drive your point if you make the connection clearer here.
Line 210: This sentence is just a list of literature, integrate it into the earlier sentence and cut down on the number of citations or still include them but not as an in-line reference just in the ().
Line 215: “In our study, also..” the structure of this sentence is awkward, edit this to improve delivery of the point you are trying to make here.
Line 225: I think what your results may be suggesting is that it is the combination of crop and soil management technique that directly affects the rate and timing of your N leachate. You are implying here that the nutrient quality and quantity of the sugar beet reincorporated into the soil after harvest had an impact in N mobilization. Do you have data on rooting depth? If roots are going deeper than what the plow can do this may add to your story here.
Line 247 to 252: This sentence is way too long
Line 252: Include Dr. Colunga’s meta-analysis work on conservation (reduced) tillage and conventional tillage in sandy arid environments with carbon deprived soils https://doi.org/10.1016/j.still.2024.106310
Section 4.2 – I think the big message here is that the benefits of CT or NIT with regards to N mobilization and leaching are extremely context dependent. You can improve the delivery and conclusion of this section by coming towards a conclusion like this rather than having a paragraph that just details a variety of different impacts from these practices in different arid and low C environments. This makes this section currently just feel like a list rather than a cohesive argument coming to a point. Enhance the delivery of that context dependence message by incorporating the literature suggested earlier but also noting that this is dependent on regional practices (crops of cultivation, rooting and biomass size, etc).
Figure E1: labels are upside down and poor resolution of axes and repetitive keys make this super messy.
Figure E2: similar as E1 but it is super blurry and almost impossible to read.
Figure E3 is similar as E1
Figure F1 has a completely different color scheme. There is no indication here of significant different between sugar beet harvest in the NIT or CT. The bottom axes has the labels off centered and the double ticks seem unnecessary and messy.
Citation: https://doi.org/10.5194/egusphere-2026-330-RC2 -
AC2: 'Reply on RC2', Annelie Holzkämper, 20 Apr 2026
The comment was uploaded in the form of a supplement: https://egusphere.copernicus.org/preprints/2026/egusphere-2026-330/egusphere-2026-330-AC2-supplement.pdf
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AC2: 'Reply on RC2', Annelie Holzkämper, 20 Apr 2026
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EC1: 'Comment on egusphere-2026-330', Carolina Boix-Fayos, 12 May 2026
EC
The authors have provided thorough and well-reasoned responses to all the referees’ comments. Their replies demonstrate that they have carefully and conscientiously addressed the reviewers’ concerns and recommendations. Furthermore, the responses indicate that substantial revisions have been undertaken to enhance the robustness and clarity of the manuscript. I expect that these improvements will be fully reflected in the revised version of the paper.
Citation: https://doi.org/10.5194/egusphere-2026-330-EC1
Peer review completion
Interactive discussion
Status: closed
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RC1: 'Comment on egusphere-2026-330', Abel Veloso, 23 Feb 2026
General comments
This manuscript evaluates the effect of non-inversion tillage on nitrate leaching in soil. This is, in my opinion, a relevant and original topic. The manuscript is concise and well written, and the study behind it was conducted throughout a good timespan. My main concern is related to the statistical analysis which, in my opinion, should be extended and deepened to support (or disprove) some of the conclusions. In addition to this, I understand that the main focus was given to the effect of treatments on nitrate leaching. However, and considering the importance of yield to farmers, I think that the focus that was given to yield should be increased throughout the manuscript. I include my specific comments below.
Specific comments
Methods: In my opinion, a subsection regarding data analysis or statistical analysis should be added at the end of the Methods section.
Results: The comparisons between treatments should be supported by statistical analysis such as t-tests or their non-parametric equivalents. Yield should be given more relevance throughout the paper, considering its importance to the farmer. In addition to this, I believe that a PCA or correlation analysis may reveal more information from the data.
Discussion: Similarly to what I have referred about the results, the effects of treatments on yield should be given a higher weight.
L80: ETa equation is shown. However, it is not mentioned in the text.
L88: Do the authors have information regarding soil sampling depth?
L119-120: A diagram representing the distribution of crop rotations and cover crops throughout the time of the experiment would increase the clarity of the explanation.
L141-142: This information should be included in the aforementioned subsection about data analysis.
L145-146: This should be checked by a statistical approach such as a t-test or a non-parametric alternative.
L145: Please indicate the Figure/Table where the cummulative ETa is shown.
L146-147: Please add here the reference to the Figure where the yield results are presented. If I am not mistakened, it is Figure F.1 (Appendix F). Maybe transfer it to the main results? In any case, the possible differences between treatments should be confirmed (or disproved) by a statistical analysis. Information about the number of replicates per treatment should be added in the legend of this (similarly to what the authors did in the legend of Figure 3).
L147: Please see my comment about the need for significant differences to be checked by statistical analysis.
L157-159: The authors stated that “nitrate concentrations were significantly higher in CT than NT”. Is this confirmed by a statistical analysis? If so, please show that information in a Figure or Table or refer to one where that information is shown.
L165-167: In my opinion, this hypothesis (and others that the authors find appropriate) should be included at the end of the Introduction. If the authors did not find this appropriate, the sentence should be re-written.
L200-202: Authors claimed that ”Results presented in this study are generally in line with Li et al. (2023), who concluded (...) that the benefits of reduced tillage for nitrate leaching reduction tend to be higher on soils with medium texture and SOC contents >1% in temperate climate zones and with longer durations of reduced tillage practices”. In my opinion, this is not accurate as the authors did not compare different soil textures, different SOC levels or different climate zones.
L221-223: The authors referred that “nitrate leaching was not significantly higher under CT than NIT during days directly after tillage, but only after the termination of sugar beet in 2014”, which seems to indicate that a statistical test (such as a t-test or Mann-Whitney test) was used. However, if I am not mistaken, the results of such test are not shown in the paper.
L249-257: The authors discuss the relationship between SOC and nitrate leaching. This is an interesting relationship which, however, was not tested. Do the authors have data available regarding the SOC content of the studied soils? If so, maybe a relationship between SOC and N leaching could be tested.
L265-289: In subsection 4.3 (Unresolved links), the authors discuss different knowledge gaps regarding the approached subject that exist in literature. In my opinion, the limitations and strengths of their present study should also be approached in this or in other subsection. This could also include suggestions for future work on this subject.
Technical corrections
L115-118: Scientific names should be written in italic.
Throughout the manuscript, nitrate is identified as NO3. I would suggest using its correct chemical formula (NO3-). In some places, it is also identified by its name (nitrate). Therefore, I would also suggest to homogenise this either by identifying it by its name or by its formula.
L159: The non-inversion tillage treatment is identified as NIT throughout the manuscript. However, here and in some other places it is identified as NT.
Citation: https://doi.org/10.5194/egusphere-2026-330-RC1 -
AC1: 'Reply on RC1', Annelie Holzkämper, 20 Apr 2026
The comment was uploaded in the form of a supplement: https://egusphere.copernicus.org/preprints/2026/egusphere-2026-330/egusphere-2026-330-AC1-supplement.pdf
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AC1: 'Reply on RC1', Annelie Holzkämper, 20 Apr 2026
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RC2: 'Comment on egusphere-2026-330', Anonymous Referee #2, 26 Mar 2026
The manuscript presents lysimeter results comparing conventional tillage (CT) and no‑inversion tillage (NIT) across three soil types under the same crop rotations over a 2–3 year period (2013–2016). The topic is timely, and the results clearly indicate differences in nitrogen losses between CT and NIT. That said, the manuscript would benefit from substantial revisions to improve clarity, structure, and the strength of its mechanistic interpretation.
In several places, the writing reads as a sequence of observations rather than a cohesive argument that explicitly links proposed mechanisms to the reported patterns. In addition, key pieces of evidence are sometimes introduced late in paragraphs, where readers would instead expect a clear synthesis or “take‑home” message for the section.
Relatedly, the manuscript includes considerable discussion of carbon’s role in mediating nitrogen loss under different tillage practices, but it is not clear that carbon content was directly measured in the study soils. The contribution could be strengthened considerably by incorporating additional measurements—such as soil carbon quantity and forms of nitrogen (and, ideally, complementary water chemistry where feasible)—to better support the claims about nitrogen retention and the drivers of observed losses.
At present, I think the manuscript requires major revision before it can be considered for publication. While the dataset is interesting and potentially valuable, the current presentation feels closer to a field report of patterns than a study that systematically evaluates multiple factors shaping nitrogen dynamics. Several important variables (e.g., carbon content, aggregate stability, nitrogen species, litter quantity/quality, rooting depth, and the impacts of plowing) are discussed as likely explanations but do not appear to be directly measured, aside from porosity. Where porosity is reported (notably in the appendix), it would also help to clearly indicate which values correspond to each treatment (NIT vs. CT), and to ensure those results are integrated into the main narrative as appropriate.
Finally, the manuscript would benefit from careful attention to consistency in figures and text, including standardized styling (colors and formatting) and consistent treatment labeling/abbreviations throughout.
Overall, I see real promise in this work, particularly in highlighting management differences and the importance of site context. To make the manuscript publication‑ready, I encourage the authors to (1) strengthen the linkage between mechanisms and observations in the writing, (2) add or more directly incorporate key supporting data (especially soil nitrogen, and carbon if central to the interpretation), and (3) more fully integrate relevant supplemental information (for example, the temperature data) into the analysis and discussion.
Lines 35-40: I think it would strengthen the authors argument if you can add a line about how widespread these tillage practices are (i.e. what proportion of farms or what percent of land undergoes method X or Y via management). This would strengthen your paper’s relevance and impact.
Graphical abstract: It currently does not suggest based on the drawing that one method goes deeper than the other. Furthermore, the abstract doesn’t show contrast with regards to changes to soil structure which appear to be central in the author’s argument.
Line 42: N2O should be subscript (similar for all other chemical formulas brought into the text and used in your graphs/figures, use correct notation and subscript!). The sentence after this makes no substantial addition to the introduction nor does it connect to the next paragraph. Reconsider structure here.
Line 49: “addressed the inconsistency in the impacts of tillage on nitrate leaching currently documented.” Or rewrite another way, its very awkwardly phrased at the moment.
Line 51: This last sentence does not connect well with the next paragraph nor is it a good concluding sentence.
Line 53: Why is this sentence separate from everything else?
Line 55: This is not a complete paragraph. Plant uptake is something that could decrease the amount of leachate correct? Then this wouldn’t be a driver but instead a factor that affects the magnitude of nitrate leachate. In this case calling these “processes that influence nitrate leaching dynamics” would be more accurate.
Line 79: Any time you place the variable from your equation into your main text, keep the same text style as the one you used in the equation description (is it subscript a or normal a?).
Line 95-97: this is exactly why you need to have a section in the introduction that can speak to how widely used this practice is globally. It enhances your research’s relevance to global community while emphasizing its importance and makes sure content like this is already introduced so that it doesn’t take up space later in the manuscript where you need to focus on the experimental details instead.
Line 105: Did each treatment receive the same cover crop treatment? It would be helpful to have a schematic here of the experimental design or a table in the SI.
Line 115: The listing of the cover crop rotations is confusing with some have a (+) and others not having this. Improve the clarity of what you are trying to express here. Is there a particular order (numbering may be better). Is there a set duo? (note this in the text). At the moment this listing is somewhat disorienting and difficult to parse. Additionally, italize scientific names.
Line 120: These values should be supplied in the SI or some note on using these to normalize your results should be made (or if they weren’t that different from each other between the treatments, this should be noted).
Line 125: Be consistent throughout your text with regards on how you will be referring to your nitrogen species (chemical formula? Written name? Also if you choose chemical formula add respective charges and subscripts – be consistent!).
Figure 1 & similar style comments for figure 2
Where is the key for the first top figure? (monthly precip and mean temp)
Label these figures as Fig 1a 1b 1c etc same for figure 2
Figure axes labels are blurry and so is a few of the graphs included here (fix please!)
Label evapotranspiration as evapotranspiration.
Monthly precipitation data is provided in Month:Year format and the following figures that are meant to be aligned over the same time periods as this precip data has Year:Month:Day. Change these to have the same formatting or change these to all be over one axes if appropriate (which I believe it is).
I would further suggest placing the name of the crop that was collected over the top of the colored boxes.
Be consistent in all of your graph labelling – will you capitalize or not? Don’t short hand write the labels, use full words to convey what you are showing and explain in detail the units in the captions if necessary.
Line 185: reformat the figure caption:
coloured background shading is in reference to cropping periods: purple (phacelia), yellow (sugar beet) … ; grey dashed vertical lines denote ploughing times; …etc
Get rid of the “=” they are hard to read/decipher with everything else that’s being listed in this caption.
For figure 2 make one large legend for parts b, c, d (label these figures accordingly)Figure 3 should be colored to match earlier graphs. However, choose a color palette that is color blind safe. Also denote significant differences on your figure in some manner (asterisks or letters).
Line 205: Your mechanistic connection here between pore structure and matrix water flow is not very clear. Are you saying that increased tillage under CT would reduce pore connectivity or increase pore presence? What about pore structure is facilitating the matrix water flow in CT vs NIT. You leave your readers without a clear connection between the two and then just citing various literature that suggest similar trends. It will really help drive your point if you make the connection clearer here.
Line 210: This sentence is just a list of literature, integrate it into the earlier sentence and cut down on the number of citations or still include them but not as an in-line reference just in the ().
Line 215: “In our study, also..” the structure of this sentence is awkward, edit this to improve delivery of the point you are trying to make here.
Line 225: I think what your results may be suggesting is that it is the combination of crop and soil management technique that directly affects the rate and timing of your N leachate. You are implying here that the nutrient quality and quantity of the sugar beet reincorporated into the soil after harvest had an impact in N mobilization. Do you have data on rooting depth? If roots are going deeper than what the plow can do this may add to your story here.
Line 247 to 252: This sentence is way too long
Line 252: Include Dr. Colunga’s meta-analysis work on conservation (reduced) tillage and conventional tillage in sandy arid environments with carbon deprived soils https://doi.org/10.1016/j.still.2024.106310
Section 4.2 – I think the big message here is that the benefits of CT or NIT with regards to N mobilization and leaching are extremely context dependent. You can improve the delivery and conclusion of this section by coming towards a conclusion like this rather than having a paragraph that just details a variety of different impacts from these practices in different arid and low C environments. This makes this section currently just feel like a list rather than a cohesive argument coming to a point. Enhance the delivery of that context dependence message by incorporating the literature suggested earlier but also noting that this is dependent on regional practices (crops of cultivation, rooting and biomass size, etc).
Figure E1: labels are upside down and poor resolution of axes and repetitive keys make this super messy.
Figure E2: similar as E1 but it is super blurry and almost impossible to read.
Figure E3 is similar as E1
Figure F1 has a completely different color scheme. There is no indication here of significant different between sugar beet harvest in the NIT or CT. The bottom axes has the labels off centered and the double ticks seem unnecessary and messy.
Citation: https://doi.org/10.5194/egusphere-2026-330-RC2 -
AC2: 'Reply on RC2', Annelie Holzkämper, 20 Apr 2026
The comment was uploaded in the form of a supplement: https://egusphere.copernicus.org/preprints/2026/egusphere-2026-330/egusphere-2026-330-AC2-supplement.pdf
-
AC2: 'Reply on RC2', Annelie Holzkämper, 20 Apr 2026
-
EC1: 'Comment on egusphere-2026-330', Carolina Boix-Fayos, 12 May 2026
EC
The authors have provided thorough and well-reasoned responses to all the referees’ comments. Their replies demonstrate that they have carefully and conscientiously addressed the reviewers’ concerns and recommendations. Furthermore, the responses indicate that substantial revisions have been undertaken to enhance the robustness and clarity of the manuscript. I expect that these improvements will be fully reflected in the revised version of the paper.
Citation: https://doi.org/10.5194/egusphere-2026-330-EC1
Peer review completion
Journal article(s) based on this preprint
Reduced tillage lowered nitrate leaching by up to 42 percent in some soils during a very rainy period without crop cover. The results suggest that reduced soil management could help protect water quality under future climate conditions with wetter winter and spring conditions.
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Annelie Holzkämper
Ernst Spiess
Clay Humphrys
Karin Meier-Zimmermann
Olivier Heller
Thomas Keller
Volker Prasuhn
The requested preprint has a corresponding peer-reviewed final revised paper. You are encouraged to refer to the final revised version.
- Preprint
(2287 KB) - Metadata XML
General comments
This manuscript evaluates the effect of non-inversion tillage on nitrate leaching in soil. This is, in my opinion, a relevant and original topic. The manuscript is concise and well written, and the study behind it was conducted throughout a good timespan. My main concern is related to the statistical analysis which, in my opinion, should be extended and deepened to support (or disprove) some of the conclusions. In addition to this, I understand that the main focus was given to the effect of treatments on nitrate leaching. However, and considering the importance of yield to farmers, I think that the focus that was given to yield should be increased throughout the manuscript. I include my specific comments below.
Specific comments
Methods: In my opinion, a subsection regarding data analysis or statistical analysis should be added at the end of the Methods section.
Results: The comparisons between treatments should be supported by statistical analysis such as t-tests or their non-parametric equivalents. Yield should be given more relevance throughout the paper, considering its importance to the farmer. In addition to this, I believe that a PCA or correlation analysis may reveal more information from the data.
Discussion: Similarly to what I have referred about the results, the effects of treatments on yield should be given a higher weight.
L80: ETa equation is shown. However, it is not mentioned in the text.
L88: Do the authors have information regarding soil sampling depth?
L119-120: A diagram representing the distribution of crop rotations and cover crops throughout the time of the experiment would increase the clarity of the explanation.
L141-142: This information should be included in the aforementioned subsection about data analysis.
L145-146: This should be checked by a statistical approach such as a t-test or a non-parametric alternative.
L145: Please indicate the Figure/Table where the cummulative ETa is shown.
L146-147: Please add here the reference to the Figure where the yield results are presented. If I am not mistakened, it is Figure F.1 (Appendix F). Maybe transfer it to the main results? In any case, the possible differences between treatments should be confirmed (or disproved) by a statistical analysis. Information about the number of replicates per treatment should be added in the legend of this (similarly to what the authors did in the legend of Figure 3).
L147: Please see my comment about the need for significant differences to be checked by statistical analysis.
L157-159: The authors stated that “nitrate concentrations were significantly higher in CT than NT”. Is this confirmed by a statistical analysis? If so, please show that information in a Figure or Table or refer to one where that information is shown.
L165-167: In my opinion, this hypothesis (and others that the authors find appropriate) should be included at the end of the Introduction. If the authors did not find this appropriate, the sentence should be re-written.
L200-202: Authors claimed that ”Results presented in this study are generally in line with Li et al. (2023), who concluded (...) that the benefits of reduced tillage for nitrate leaching reduction tend to be higher on soils with medium texture and SOC contents >1% in temperate climate zones and with longer durations of reduced tillage practices”. In my opinion, this is not accurate as the authors did not compare different soil textures, different SOC levels or different climate zones.
L221-223: The authors referred that “nitrate leaching was not significantly higher under CT than NIT during days directly after tillage, but only after the termination of sugar beet in 2014”, which seems to indicate that a statistical test (such as a t-test or Mann-Whitney test) was used. However, if I am not mistaken, the results of such test are not shown in the paper.
L249-257: The authors discuss the relationship between SOC and nitrate leaching. This is an interesting relationship which, however, was not tested. Do the authors have data available regarding the SOC content of the studied soils? If so, maybe a relationship between SOC and N leaching could be tested.
L265-289: In subsection 4.3 (Unresolved links), the authors discuss different knowledge gaps regarding the approached subject that exist in literature. In my opinion, the limitations and strengths of their present study should also be approached in this or in other subsection. This could also include suggestions for future work on this subject.
Technical corrections
L115-118: Scientific names should be written in italic.
Throughout the manuscript, nitrate is identified as NO3. I would suggest using its correct chemical formula (NO3-). In some places, it is also identified by its name (nitrate). Therefore, I would also suggest to homogenise this either by identifying it by its name or by its formula.
L159: The non-inversion tillage treatment is identified as NIT throughout the manuscript. However, here and in some other places it is identified as NT.