Ridge-Furrow Mulching Enhances Capture and Utilization of Rainfall for Improved Maize Production under Rain-Fed Conditions

Round 1

Reviewer 1 Report

Manuscript Review   Agronomy - 1698739

Effectiveness of ridge-furrow mulching practices for efficient use of precipitation for maize production under rain-fed conditions

 

Potential Alternative title:   Ridge-furrow mulching enhances capture and utilization of rainfall for improved maize production under rain-fed conditions

 

Summary:

This paper reports convincing positive impacts of an alternative ridge-furrow system, using various mulching treatments to capture and conserve more water to support improved maize performance.   Some improvements in the description of the system installation could help readers to understand potential challenges more fully for execution of this method at scale.  Also, some discussion of possible problems with planting corn in furrows in a wetter season might be in order.   Statements of the financial advantage of the system need to be written differently, as they are misleading currently.   There are several recommendations for improved statistical presentation of results in the Figures.  Overall, this report provides valuable insight into a promising method of improving water capture and utilization in arid and semi-arid climates.  Projection of the use of this by small landholders should be highlighted.

 

Specific Comments:

Abstract:

Line 31-33.  The early emergence response is a minor finding in my opinion.   I would rewrite the sentence:  “The BM treatment consistently increased soil moisture and temperature, resulting in earlier emergence, and increased plant height and plant biomass, compared to the WM treatment.”

 

Line 38-39.   This claim of net income is stated incorrectly here.   I would rewrite the sentence:  “Net income for the BM treatment was the highest of all the treatments, at $1226/ha^-1, and $335 ha^-1 greater than WM.”

 

 

Introduction:

 

Line 59.   This statement is unclear.  I assume the author is claiming that the ridge-furrow system improves maize yield to a larger degree under the driest conditions.  Somehow this needs to be restated to make that clearer.   Also, is there a reference that reported these yield data under different rainfall amounts?  None is cited here.

Lines 69-79.   There is no mention of the possible negative impact of planting in furrows if excessive moisture were to occur, especially early in germination and emergence.   In both 2017 and 2018, >100 mm of rainfall occurred soon after (within 1 week) of planting, and I would assume the furrows became extremely wet and flooded after this much rainfall was harvested from the ridges.   Please introduce the possible risk of excess water in furrows here, and also in the Discussion.  Growing temperatures are extremely high, so perhaps the plants are growing so fast that wet conditions would not harm the crop?

 

Materials and Methods:

Line 88.   Please state total rainfall for each of the two years.  The two years have very different total rainfall patterns, so would be good to state total rainfall for each year.

Line 94.  Perhaps you could improve the diagram in Figure 2.  Perhaps you could mark the 30 cm wide ridge and the 60 cm wide ridge with those dimensions.  So you actually have two rows 30 cm apart, and then two rows 60 cm apart?  This would be similar to a “skip row” planting arrangement.   Also, you need to describe the final plant density in plants ha^-1. 

Line 106-112.  The term “whole sowing” is very ambiguous.  Please describe in more detail.   Did you drill the seed into the plastic mulch, or plant by hand?   Please provide better overall description of planting and thinning with the challenge of plastic mulch.  

Line 155.   Better describe time window when photosynthesis data was collected.  I don’t think you were collecting photosynthesis data up to 11 pm (23:00 hr).   Should be 11 am?

 

Results:

Line 188-191.   This should be restated since there was a significant difference in HI between BM and TM vs WM in both years (Table 2).

Table 1 and Table 2 have incorrect Year headings (2015, 2016).

Line 206.   Do you have an ANOVA on leaf area index (Figure 3) to prove the means are different?   Same concerns for data in Figures 4 and 5.

Line 230.  This statement is not true.  Treatment differences in SWS between 60 an 120 DAS in 2017 appear to be quite significant, compared to WM.

Line 232.  This statement is confusing.   How could there be more initial water stored in the WM.   Was the heavy rainfall occurring earlier in July running off the plots in the BM, and TM treatments???  You need to explain this phenomenon and the early water absorption conditions better.

Line 240. Do you have an ANOVA to support significance statements for data in Figures 6, 7 and 8.   The means certainly show good differences, but you must include an ANOVA table to confirm significant main effect of treatment (F value).

Line 270.  Your conclusions need to be restated.  Suggested: “Net income was highest for the BM treatment, $1226 ha-1, and benefit:cost ratio was improved by 16%, compared to WM.  Net income difference for BM vs WM was $335 ha^-1 (Table 3).” 

 

Discussion:

 

Line 287.  While I believe soil temp was increased, you did not report any soil temp data, so the statement that BM and TM “enhanced the soil temperature significantly” is really not justified.    You can just continue to state that reasonable expectation, but you cannot prove it statistically.

 

Line 297.   Again, with no soil temp data, you cannot prove that the BM and TM treatments “significantly” increased soil temps. 

Line 305-307.  You are likely overstating the impact of early soil temp on the outcome of your experiment.  At your extremely high growing temps, I doubt that temperature was limiting maize development.   You need to build your story around the obvious, and measured effect of the BM and TM on improved available soil moisture.   Your statements on that in lines 310 and 313 are much better.

Line 316.   You should also discuss the potential impact of improved soil storage on N  uptake by the root system, which would also support greater biomass production above ground.  

Lines 322-325.  Perhaps you could expand on the comparison of ridge-furrow to flat planting.  It appears to me that you have not fully completed your economic analysis without a comparison to typical flat land planting.  Unfortunately, you did not have a flat land treatment in your experiment, but I would assume you could still present some additional discussion based on the Ren et al. paper.  My other concern is, can growers manage the logistics of BM and TM on larger areas, i.e. > 1 ha, or is this strictly a small landholder type of system?  Please discuss some components of practical use in your region.

 

 

Conclusion:

Lines 340-39.   The conclusion is very well written, and it provides a good summary of the key findings.

Author Response

Response to reviewer comments has been uploaded

Author Response File: Author Response.docx

Reviewer 2 Report

The abstract is not impressive at all. Lack of problem proposition, lack of hypothesis, and poor English text are the main problems of the abstract.

Introduction is not enough. Research background is poor. Research innovation is not clear. Authors only mentioned the cultivation of maize in the furrow as an innovation. Apart from the fact that this can not be considered as an innovation, however, previous studies have been conducted in this way, which was exemplified in the comments.

Most of the descriptions of the Results are not impressive.

The discussion is not well done, it is also very short. In many cases, the discussion is based on the findings of other research rather than the results of the research.

Conclusion is not appropriate.

There are some comments into the text that can point out the problems in more detail.

Extensive editing of English language and style required.

Comments for author File: Comments.pdf

Author Response

Response to reviewer comments has been uploaded

Author Response File: Author Response.docx

Reviewer 3 Report

Comments

 

SUMMARY

The paper addresses the research area related to Water Use and Irrigation in the MDPI Agronomy journal. I believe that the target journal is an appropriate forum for this article. The main objective of this experiment was to investigate the role of the ridge-furrow mulching on the physiological, growth and yield of maize by collecting the rainwater and re-allocating it to the furrow where the crop was planted.

 

BROAD COMMENT

This study is of great importance for maize production in Pakistan. The Introduction section is well written with recent references. The methods were well described and in detail allowing a good understanding of the results of the study. I appreciate the fact that the authors conducted two seasons of the experiment (2017 and 2018). This allows taking into account the variability due to the spatial distribution of the crops and minimizing the errors arising from the experimental design. They discussed well the results of the study. However, I have some concerns about the different parts of the manuscript. I suggest a major revision to address a few issues. If the authors address carefully the comments, I’ll recommend publication of the manuscript in the journal.

 

SPECIFIC COMMENTS

• Figure 1. please, put the x-axis in calendar dates like 5-Jun 2017, etc…It is easier to link with the months of the year.
• Figure 2. Something went wrong with the legend indicating the different parts of the diagram. Please, check this and fix it.
• Lines 160-164: Provide a citation for software Statistix 8.1 and Sigma plot 11.0

To conduct an ANOVA test which is a parametric statistical test, one should be sure that the data is normally and homogeneously distributed. Did you conduct normality and homogeneity tests on the data before the ANOVA? Please, do include this in the manuscript.

• The authors failed to put the implications of the findings of the study for maize production in Pakistan in the conclusion and abstract sections. Please, do include that.

Author Response

Response to reviewer comments has been uploaded

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

The manuscript was improved based on the suggestion of my review. I would like to propose mainly checking carefully spelling and reading carefully the final form of the manuscript.

Reviewer 3 Report

I have undertaken a review of the manuscript (revised) as well as the attached author responses to the initial review. I am satisfied with the revisions made by the authors as they have addressed most, if not all, of my initial comments. Therefore, I do believe that the manuscript has been significantly improved and now warrants publication in Agronomy.