Estimation of Hydraulic Parameters from the Soil Water Characteristic Curve
Round 1
Reviewer 1 Report (Previous Reviewer 1)
The authors now have improved the manuscript by incorporating my suggestion, especially adding literature on previous studies about SWCC and hydraulic parameter estimation of different soil types for both laboratory and field experiments.
Minor Comments: I would suggest not including mathematical equations 1-4 in the introduction sections. These equations should be included in method section.
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report (Previous Reviewer 2)
The article has made a good revision to the first draft. However, the article only selected two types of soil to verify the method proposed in the article, which is not representative enough. Therefore, further verification tests are needed.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report (Previous Reviewer 4)
I am happy with the responses to my questions and with the overall format of the manuscript
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report (Previous Reviewer 2)
The author has made good revisions to the article and it is recommended to accept it.
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
Round 1
Reviewer 1 Report
The authors used the soil water characteristics curve for the estimation of hydraulic parameters (Field Capacity (FC) and Permanent Wilting Point) for water saving. In the current study, SWCC along with FC and PWP of two soil types were obtained via specific experimental procedures in the laboratory. Results show that the soil water characteristics curve gives excellent results for FC and overestimates the PWP.
The English language used needs editing throughout with a moderate level of change required as there are many grammatical errors.
Major Comments:
There should be more extensive literature on previous studies about SWCC and hydraulic parameter estimation of different soil types for both laboratory and field experiments.
Minor Comments:
Lines 31-46: There should be some citation for explaining the soil water characteristics curve and soil moisture.
Reviewer 2 Report
Soil water characteristic curve is one of the important parameters of soil hydraulic characteristics, which plays an important role in accurate simulation of soil water movement. In this paper, it is of great significance to study the estimation of soil and water hydraulic parameters by soil water characteristic curve. However, there are the following problems:
1. The structure and writing of the article are not standardized, more like a test report.
2．The error of the soil wilting coefficient estimated from the characteristic curve by using soil moisture is too large. In addition, it is difficult to directly apply the soil hydraulic parameters determined at the point scale to the farmland or regional scale. That is to say, this method has certain difficulties in practical application.
3. Only two soil types are selected in this method, which can not represent the common soil types, that is, the reliability of the method needs to be further verified.
Reviewer 3 Report
The comments are as follows:
The presented method, leads to estimation of crucial hydraulic parameters that can be used in irrigation planning and water saving practices. This study is of great significance to correctly evaluate soil moisture content and promote the development of water-saving agriculture. However, the design of the figure in the text is unreasonable, so it is recommended to place 2 figures in each row, and 4 figures in 2 rows in total. The model of TDR sensor and the company from which it is manufactured are not mentioned in the article. Two samples of different soil types (sandy, and sandy loam) were selected, but it does not describe the thickness of the soil layer collected? All collected soil shall be mixed and loaded into plexiglas column? I think the conclusion is appropriate. The format of references should conform to the requirements of Sustainability, the current document format and citation method are incorrect.
Reviewer 4 Report
The paper presents the results of experimental procedures performed in the lab that aims to reduce the time required to obtain FC and PWP. To look for alternative methods to obtain these parameters is very important, given the importance they have in hydrological modeling. The paper is well structure and detailed in terms of the laboratory experiments. However, there are some points I'd like to comment:
1. It is not clear the diferences between the proposed and the traditional method to estimate FC and PWP
2. It is not clear if the proposed method really reduces the time or the difficulty to obtain FC and PWP using traditional methods
3. They concluded that the method is more suitable to determine FC than PWP. However, I didn't see in the paper the mention to an equipment very used in lab - Hyprop, from the Meter Group - designed to build a continuous SWCC curve.
