Optimization of Subsurface Drainage Parameters in Saline–Alkali Soils to Improve Salt Leaching Efficiency in Farmland in Southern Xinjiang

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

General comment:

Overall, the titled research is an interesting piece of work with an important results and discussions with logical flow of ideas. Its writ-up and command of language is also good. Just indicated a few rephrasing are required for publication. In addition, strengthening the discussion of results with additional literature could also enhance the depth and relevance of the findings.

 

Specific comments:    

1. Introduction:
   1. Line 100-102: rephrase the sentence for clarity
   2. Given, the study area is characterized by very low average annual precipitation of 47.9 mm and huge evaporation of 2279.1 mm annually, shallow Groundwater depth (around 1.5 m) on Fig.2, secondary salinization due to capillary water rise is imminent. So, I am wondering why this study couldn’t include “the rate of salinization due to capillary rise” as well.
2. Materials and Methods
   1. Table 2: Explain on how you selected these specified interval and burial depths
   2. Equations 5-6: add descriptions for Ks and E
   3. Line 197-98: rephrase for clarity
   4. Line 204-206: requires rephrasing for clarity
3. Results:
   4. Rephrase “Figure 4.is a graph showing the variation of drainage flow between treatments during drenching of a subsurface drainage project.” as “Figure 4. Variation of drainage flow between treatments during drenching of a subsurface drainage project.”
   5. Rephrase “Figure 5. is a graph showing the variation in conductivity of drainage water between treatments during drenching of a subsurface drainage project.” as ““Figure 5. Variation in conductivity of drainage water between treatments during drenching of a subsurface drainage project.”
   6. Rephrase “Figure 6. presents the variation in unit-area drainage volume (mm) and unit-area salt discharge (kg·m⁻²) under different treatments (A1–A5) during spring irrigation (SI) and winter irrigation (WI) in 2023 and 2024.” as ““Figure 6. Variation in unit-area drainage volume (mm) and unit-area salt discharge (kg·m⁻²) under different treatments (A1–A5) during spring irrigation (SI) and winter irrigation (WI) in 2023 and 2024.”
   7. Rephrase “Table 4. Results of multivariate analysis of variance.” as “Table 4. Variance of Ratio of Drainage to Irrigation and Drainage Salt Efficiency Coefficient.”
   8. Rephrase “Table 5. Post-hoc Multiple Comparisons.” as “Table 5. Post-hoc Multiple Comparisons of Ratio of Drainage to Irrigation and Drainage Salt Efficiency Coefficient.”
   9. Rephrase” Figure 7. illustrates the variation of the DSEC under different pipe spacing and burial depth conditions.” as “Figure 7. Variation of the DSEC under different pipe spacing and burial depth conditions.”
   10. Rephrase “Figure 8. illustrates the proportional changes in soil water storage, drainage, and evaporation under different leaching quotas.” as “Figure 8. Proportional changes in soil water storage, drainage, and evaporation under different leaching quotas.”
4. Discussion:
   4. A few literatures are cited particularly on subtopics such as 4.1: so reinforce with more and latest literatures
   5. Line 298: You have stated that “High soil pH also magnifies this effect in semiarid and arid regions due to the impacts of pH on edge charge in clays and hence on dispersion”. But, you need to discuss considering the temperate nature of your study area.
   6. Line 414-415: it seems that “mulching” is considered as “irrigation method”; in fact not.
5. Implications:
   1. I am in contrary to the authors’ keen expression of geographic limitation of this study. I feel that this interesting result of the study could rather be applicable to other similar areas within China and over the Globe as well, provided that the authors make an additional effort to sort out those areas using GIS/RS systems and appropriate search tools.

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Review:  Optimization of subsurface drainage parameters in saline-alkali soils to improve salt leaching efficiency in farmland in southern Xinjiang

 

 

This study conducted field experiments from 2023 to 2024 to evaluate the effects of varying subsurface drainage configurations—specifically burial depths (1.0–1.5 m) and pipe spacings (20–40 m)- on drainage 17 and salt removal efficiency in silty loam soils of southern Xinjiang, aiming to develop an optimized scheme balancing water conservation and desalination.

A resubmission should consider and need to be clarified the following aspects and concerns.

 

My major concerns are:

 

• The choice of the equidistant spacing of the drains needs to be substantiated. Otherwise the choice seems completely arbitrary and subjective.
• The final conclusion is that the best solution is to place the drainage pipes at a great depth (1.5 meters deep) and the spacing of the pipes to be small (20 meters). But this is to be expected. It is worth having an economic analysis if this is economically effective.

 

 

Specific  comments

l.108. please give the maximum and minimum values

In table 1 write that the values ​​in the fifth column are the values ​​of the bulk density

l.124. In figure 3 it appears that the length is 106 meters and NOT 110 that you mention at this point. Please explain.

Immediately after equation 5, explain the terms included in the equation

l.196. Please explain why the value of Ks is taken as 1 and give the corresponding units of Ks.

The caption for figure 4 needs better wording.

l.299-302. This conclusion is obvious; no special experiment was needed to establish it.

l.381. please give some measured values ​​of permeability

 

 

 

 

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

Dear Authors

The changes and the additions which were made has considerably improve the manuscript. Consequently, i suggest it to accept for publication