Round 1

Reviewer 1 Report

Dear Authors,

Manuscript ID sustainability-2192426 presents the research on the influence of irrigation using poultry wastewater on the pomological properties of olives and oil. The main idea is well presented although the manuscript needs more attention and corrections in the terms of wastewater, water and soil characteristics.

The major failure of the article is the avoidance of the very important part of the complex system: water/wastewater-soil-plant. The Authors present only results relating to the plants except for the water/wastewater and the soil. However, at the same time, the Authors tried to conclude the reason for the accumulation of heavy metals in the plants. I cannot agree with this way.

The article should contain:

- information about the wastewater origin (production line and sources of untreated wastewater),

- schedule of wastewater collection, conditions of storage,

- characteristics of wastewater introduced to the lots (major parameters + heavy metals + specific organics + sanitary parameters),

- characteristics of the water used in the experiment (ion balance or shortened characteristics) (Lines 224-227, 463-464: Could be the tap water the source of Cr, Al, Ti, V, Ni, Sr and Ba?),

- characteristics of soli occurred in used lots.

 Lines 80-89: How were the lots separated from each other to prevent the interaction of different irrigation types?

Please, give proof, that the trial of 4 trees is sufficient to evaluate the influence of the irrigation medium. What about the statistic in therms of the trees number, not collected fruits?

Best regards,

Author Response

« Manuscript ID sustainability-2192426 presents the research on the influence of irrigation using poultry wastewater on the pomological properties of olives and oil. The main idea is well presented although the manuscript needs more attention and corrections in the terms of wastewater, water and soil characteristics ».

Comment 1: The major failure of the article is the avoidance of the very important part of the complex system: water/wastewater-soil-plant. The Authors present only results relating to the plants except for the water/wastewater and the soil. However, at the same time, the Authors tried to conclude the reason for the accumulation of heavy metals in the plants. I cannot agree with this way.

Response : Results about water and wastewater physicochemical analysis had been published on previous publication ; Short-time irrigation on young olive tree (Olea europaea L. cv. Chemlali) with untreated industrial poultry wastewater investigation of growth parameters and leaves chemical composition (https://doi.org/10.1007/s11356-021-14261-2).

The effect of the poultry wastewater on soil chemical properties and its microbiological quality  had been studied. The results are the subject of another publications being published.

 

Comment 2: The article should contain:

- information about the wastewater origin (production line and sources of untreated wastewater),

- schedule of wastewater collection, conditions of storage,

- characteristics of wastewater introduced to the lots (major parameters + heavy metals + specific organics + sanitary parameters).

Response: Details about wastewater sampling were added in material and methods section (from line 81 to line 90).

The microbiological characterization of the different water qualities used in this expirement was published  « Assessment of Bacterial Diversity of Industrial Poultry Wastewater by Denaturing Gradient Gel Electrophoresis (DGGE) and the Cultivation Method in Order to Inform Its Reuse in Agriculture »  (https://doi.org/10.1155/2022/6065305).

 

Comment 3: Characteristics of the water used in the experiment (ion balance or shortened characteristics) (Lines 224-227, 463-464: Could be the tap water the source of Cr, Al, Ti, V, Ni, Sr and Ba?).

Response: According to the heavy metals determination in TW, PWW and PWTWW samples. Results showed that all heavy metals concentrations are low and considered as respectful to the requirements set by the Tunisian standards for the reuse of wastewater in irrigation                       (NT106 .03) as well as for the FAO standards in order to the reuse of wastewater in agriculture for a short term.

However, the determination of the concentrations of heavy metals in soil (from 0 to 40 cm of depth) before the beginning of the experience showed high values. At the end of the experience, an important decrease was registered. In fact, heavy metals were accumulated by olive tree.  

Their accumulation in fruits and olive oil is due to the stimulation of their absorption from the soil. In fact, this accumulation is a fertilization result since it has been proved that mineral fertilization enhance heavy metals absorption.   

Comment 4: Characteristics of soli occurred in used lots.

Response: Soil characteristics are described in material and methods section (plant material) (Line 95) 

 Comment 5: Lines 80-89: How were the lots separated from each other to prevent the interaction of different irrigation types?

Response: The intra lots distance is 16 m (line 95)

Comment 6: Please, give proof, that the trial of 4 trees is sufficient to evaluate the influence of the irrigation medium. What about the statistic in therms of the trees number, not collected fruits?

Response:  The study plot only allows for 4 trees per lot however a previous study  (Sdiri et al., 2020 ) « Quality characteristics and chemical evaluation of Chemlali olive oil produced under dairy wastewater irrigation » has used 5 trees per lot (https://doi.org/10.1016/j.agwat.2020.106124).

Reviewer 2 Report

This paper surveyed the effects and merit of industrial poultry wastewater to irrigate olive plants. It is good utilization of the wastewater and it has good meaning on SDG's thoughts, too.

The paper precisely showed chemical elements in the olive fruit. However, some hormone must be in the poultry wastewater, too. Because, animals have been feed with something hormone. How about this point? If you can add the hormone effects, please describe them.

    

  

Author Response

« This paper surveyed the effects and merit of industrial poultry wastewater to irrigate olive plants. It is good utilization of the wastewater and it has good meaning on SDG's thoughts, too ».

Comment 1: The paper precisely showed chemical elements in the olive fruit. However, some hormone must be in the poultry wastewater, too. Because, animals have been feed with something hormone. How about this point? If you can add the hormone effects, please describe them.

Response: You are right, previous studies have mentioned the presence of steroid hormones in wastewater. Some studies had evaluated the effect of exogenous hormones on plant growth.  However, according to our knowledges no data was found about their effect on fruits or olive oil quality.

Reviewer 3 Report

The manuscript entitled “Nutritional Quality investigation of Olive oil related to short time irrigation of olive trees cv Chemlali with untreated industrial poultry wastewater” is an interesting contribution to the use of wastewater from the poultry industry to irrigate Oile trees and their influence on the olive oil quality. The introduction is well written, the objective is clear, material and methods are reproducible, conclusions are supported by data. However, there are several points that need clarifying before accepting the manuscript

 

 

Comments

 

General

Author affiliations. Please revise the author affiliations

 

 

The number of cites used is high, please revise if all cites are necessary.

 

 

Material and Methods

 

Section 2.7 Statistical analysis. Please include details about PCA analysis

 

 

Results

 

Table 2

Please add data about dispersion measurements

 

 

Figure 1. Please add details about the dispersion bar (standard deviation, experimental error, variance, etc?)

 

 

 

Please polish Table 3

 

 

Please polish Figure 3

 

 

Author Response

The manuscript entitled “Nutritional Quality investigation of Olive oil related to short time irrigation of olive trees cv Chemlali with untreated industrial poultry wastewater” is an interesting contribution to the use of wastewater from the poultry industry to irrigate Oile trees and their influence on the olive oil quality. The introduction is well written, the objective is clear, material and methods are reproducible, conclusions are supported by data. However, there are several points that need clarifying before accepting the manuscript

 

Comment 1:  Author affiliations. Please revise the author affiliations.

 

Response:  Authors affiliations were revised

 

 

Comment 2:  The number of cites used is high, please revise if all cites are necessary.

 

 Response : All references are necessary we tried to cite only recent studies

 

Comment 3:  Section 2. 7 Statistical analysis. Please include details about PCA analysis.

 Response : PCA analysis details were added (from line 169 to 175)

 

 

Comment 4:  Results /Table 2: Please add data about dispersion measurements.

 

Response : Measurements were performed just once

 

 

Comment 5:  Figure 1. Please add details about the dispersion bar (standard deviation, experimental error, variance, etc?)

 

 Response : Some details about standard deviation and variance were added in the section                         3. 3. Effect of wastewater reuse on total phenolic content since we can not add them in the figure  (from line 227 to 232)

 

 

Comment 6:  Please polish Table 3/ Please polish Figure 3

Response : We tried to make them more clear.

Round 2

Reviewer 1 Report

The corrections of manuscript ID sustainability-2192426 are minimal.

In my previous review, I informed the Authors about the gaps in the text. In my opinion, it is important to prepare the manuscript as best as possible. The authors use the information from their previous papers, but the references to these are insufficient. Putting only the reference without suitable commentary (water, wastewater, soil synthesizing description) is unfair relative to the future article readers. The reader deserves to take care of the greatest possible comfort of the message.

Author Response

Sustainability Manuscript ID: Sustainability-2192426 Title: Pomological and olive oil quality characteristics evaluation under short time irrigation of olive trees cv Chemlali with untreated industrial poultry wastewater Thank you for your interest in our manuscript and for your suggestions for improving it. Please find hereafter the list of the amendments. Reviewers’ comments: Reviewer #1: Comment: In my previous review, I informed the authors about the gaps in the text. In my opinin, it is important to prepare the manuscript as best as possible. The authors use the information from their previous papers, but the references to these are insufficient. Putting only the reference without suitable commentary (water, wastewater,soil synthesing description) is unfair relative to the future article readers. The reader deserves to take care of the greatest comfort of the message. Response: A description of our previous results already obtained for poultry wastewater (PWW) used in the current experience (from line 75 to line 82). Since new references were added the reference numbers and the reference list were updated.

Round 3

Reviewer 1 Report

Dear Authors,

you explore the plant-wastewater/water-soil issue to a small extent, focusing only on pomological quality. It's ok in terms of research scope. However, when this area is ommited in discussion it's look like incomprehension of wastewater reusing challange. Your corrections are really assertive, so I have no idea how to proceed.

Best regards

Author Response

Sustainability

Manuscript ID: Sustainability-2192426

Title: Pomological and olive oil quality characteristics evaluation under short time irrigation of olive trees cv Chemlali with untreated industrial poultry wastewater

 

Thank you for your interest in our manuscript and for your suggestions for improving it. Please find hereafter the list of the amendments.

 

Reviewers’ comments:

Reviewer #1:

Comment: you explore the plant-wastewater/water-soil issue to a small extent, focusing only on pomological quality. It's ok in terms of research scope. However, when this area is ommited in discussion it's look like incomprehension of wastewater reusing challange. Your corrections are really assertive, so I have no idea how to proceed.

Response: In order to better understand the effect of wastewater reuse on the accumulation and translocation of heavy metals from the soil to the plant, the discussion part has been developed and new references were added. (from line 501 to line 515).