Review Reports

Round 1

Reviewer 1 Report

 

In this review authors wanted to illustrate about the nutrient management by combining the mass balance with water use efficiency (WUE), tissue nutrient concentration, electrical conductivity and CO₂ concentration.

This manuscript needs further revision before the final submission and authors must fulfill the following comments:

1.    Authors used a Wikipedia reference for the mass balance it’s a suggestion to use reference from a recent paper as the whole review is revolving around the concept of mass balance so it will be more helpful for the readers during back referencing.

2.    Author should also change the writing part for the better understanding of the reader’s example:-

o   In equation1, in place of “tissue %” use “tissue nutrient                    concentration (%)” as explained by formula in equation2.

o   In figure 2, in place of “g nutrient” use “nutrient (g)” likewise other units should be changed to this format.

o   In table4, tissue (%) should be replaced with tissue concentration (%).

o   Rephrase line 100 on page no. 3. (Reduce WUE upto 3-1gL^-1)

o   Subheading 2.6 is complicated, rephrase it for better understanding.

o   Subheading 13.1 volume: surface area should be abbreviated as “V: SA” in place of “V: CA”.

3.    Authors should explain the use of increased concentration of Zn, Mo, Ni, in USU hydroponic solution, as like they have given a valid reason of others macro and micronutrients.

4.    Authors can give few examples of nutrient uptake by intermediate and passive strategy. (as they have explained for Mn uptake by  active )

5.    Heading no. 4 and 6 are both explaining about the electrical conductivity so it should be in sequence. (heading 6 should be at place of 5)

6.    Authors should give a separate heading before explaining about chelate iron, silicon, copper, or elaborate about them in sub point under second heading where others are explained.

7.    Sub headings should be either bold, presently they are mixed with the context.

8.    Following reference may be considered to add another subtitle on  “sustainable nutrient management in agriculture through nanotechnology”. This may gain more appreciation from the readers.

doi.org/10.1021/acsomega.1c05245

doi.org/10.1016/j.cej.2019.121995

 

 

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

The manuscript is very interesting and the presentation of it is remarkable. Authors just can rephrase the abstract with the relevant content. Moreover, cross check for typological error throughout the manuscript.    

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

Comments

The article reviews about the principle of nutrient management under hydroponic closed system. Article is well written, discussing the mechanism of nutrient flow in solution and plant tissue highlighting the role of WUE, pH on nutrient availability and uptake, antagonism, and synergistic effect along with the beneficial and toxic effect of various elements for plant growth. This paper could be of high significance for academicians and researchers across the globe. In this paper, author have discussed focusing on some plants for example, lettuce, tomato etc; it would be good to know the mechanistic nutrient flow (ion exchange, uptake behavior) for other hydroponic crops and vegetables as well which might differ among each other. Author have discussed about CO₂ and humidity and their role in WUE and nutrient flows. It would be good to discuss the role of temperature as well which might influence CO2, stomatal aperture, transpiration, photosynthetic activity thereby affecting the nutrient cycling in the systems.

Specific comments

Line 181 (Table 1): Tissue concentration in all leaves, specify crop! In the later sentence (line 196-217), you are talking mostly about Lettuce, if so, you can mention it in the table.

Line 196 to 218: You have discussed about secondary and micronutrients. What about primary nutrients (N, P and K), it was not considered for adjustments?  

Line 288-290. You may highlight about nutrient dilution and accumulation during plant nutrient uptake.

line 318 (section 3.1). Plant prefer nitrate over ammonium for uptake. You may also discuss about this with relevant reference.  

389-391. Already discussed about both N form uptake in line 319-320. You may reduce the text and fine tune here.

Line 448 – 460 (section 4.2) I would suggest reducing the content and merged with section 4.1.

Line 666-669: Provide reference.

 

Author Response

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Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Authors have addressed the comments, it is good to publish.

Author Response

Thank you for your comments. They were helpful to improve the manuscript.