Control of Aquatic Weed Eichhornia crassipes Using Florpyrauxifen-benzyl Herbicide—Case Study in Cangkuang Lake (Indonesia)

Round 1

Reviewer 1 Report

It is an interesting paper that deserves publication once the authors have addressed highlighted comments. 

Reviewer^,s  recommendations:

A= authors, R= reviewer

Title: R:   Control of aquatic weed Eichhornia crassipes using Florpyrauxifen-benzyl herbicide – case study in Cangkuang Lake (Indonesia)

 Line 11 - A: Water hyacinth (E.crassipes) …..R: Water hyacinth (Eichhornia crassipes (Mart). Solms) 

Line 18 - A: experimental plots with a size of 1 m xm1 m. R: experimental plots with a size of 1 m x 1 m

A: Florpyrauxifen-benzyl, starting at a dose of 15 g a.i.ha… R: Florpyrauxifen-benzyl, starting at a dose of 15 g a.i/ha

Line 23 - A: …with a growth reduction percentage of up to 100% at 42 DAA…  R: DAA? – please describe abbreviation - days after herbicide application.

Line 25 – 26 - A: These parameters can be affected by climatic factors such as air temperature, wind speed, and precipitation. … R: delete sentence, to general – the important is  the influence of used chemicals on water quality parameters.

Line 28 – 29 - A:  Overall, the study suggests that Florpyrauxifen-benzyl is an effective herbicide…. R:  This study suggests that Florpyrauxifen-benzyl can be an effective herbicide….

Line 47 - A: .. , with the total area of 340.775% ha… R: Why %?

Line 105 – A: Table 1. Study climate conditions November to December 2022. R: Insufficiently precise title. Are the results presented in the Tab. obtained from the Garut Space and AtmosphericTechnology Test and Observation Center or by authors research?  To which geographical area results are refer?  The values in the table – decimal numbers are written with a dot, not with a comma.  89,96 instead 89 – 96.

Line  112- 117 A: . A total of 32 boxes measuring 32 1 m x 1 m were used…. R: This part belongs to the design of the experiment as described later, so it is unnecessary here.

Line  135 – 150 R: In this part of description of Water Quality Measurement the same thing is repeated twice!

Line 158 – 159 A: Based on Government Regulation No. 22/2021 … Regulation No. 82/2001  R: Please add the references!

Line 168 – 169 A:  Various information can be collected from the item under this study,… R:  What does this mean? Delete.

Line 178 – 180 A.  The weeds samples were evaluated by measuring their dry weight, which was ob- tained through the process of destruction and drying in an oven at 80oC for 48 hours until the values were constant at 14, 28, and 42 DAA.   R: This is not statistical analyze!!! It was already described in the Line 172-173.

Line 190 - 318:  3. Results  - general comment: It would be more appropriate to divide results into two parts: 3.1.  Effect of herbicide on the weed E. crassipes; 3.2. Effect of herbicide on water quality

Figures 3. – 7.  – general comment R: Insufficiently clear fig. titles – needs to be supplemented - application of the three types of herbicide, What is FPB in Fig.3.? What is HSA in the Fig. 4??Generally - unknown abbreviation!

Line 368 – 369.  Table 4. River and lake water quality standards based on Government Regulation of the Republic of Indonesia No. 22/2021 [52]. R: Table also contains the results of the conducted research, so that should be in the title of the table. Moreover, please remove Table 4 from the Discussion to the Results!

Conclusion: R: It is necessary to point out that “the study also highlights the importance  of considering the potential environmental impact and toxicity of herbicides before their use in aquatic ecosystems“. Also, this can be be commented in the Discussion.

Author Response

Dear Reviewer

I have revised all your comments 

Author Response File: Author Response.pdf

Reviewer 2 Report

The aim of the work is to identify the most efficient type and dosage of herbicide and minimize its influence on the ecosystem. It is not specified in the discussion chapter and especially in the conclusions if this objective has been achieved and what is the maximum yield obtained, what is its efficiency.

The discussions should refer to the results obtained during the almost two months and make a systematization of them, and the conclusions should make a synthesis of the experimental results in the sense of identifying and highlighting the values of the modified parameters for which the values of the monitored water quality indicators are optimal and also which is the recommended herbicide among the three (one or combinations).

Using the results obtained in this study, I recommend a serious, long-term analysis of the effects of the selected herbicide on fish, which should be the subject of another scientific paper. I suggest this because it is extremely dangerous for the ecosystem to use an herbicide not tested according to the legislation in force in the respective country. The time taken into account in this study (less than two months) seems to me far too short to obtain results that lead to the safety of the fish species in the lake.

What happens to the "dead" plants? don't they affect the water quality of the lake and the ecosystem if they are left to rot in its mass? If and how are they recycled as waste?

Author Response

Dear Reviewer

I have revised all comments (revised file is attached)

Author Response File: Author Response.pdf

Reviewer 3 Report

The authors study contributed to increase knowledge concerning the enviromental fate of a novel herbicide for the control of aquatic weeds.

The experiments were carried out in open field, not in controlled conditions. Data on temperature and precipitation during experimental trial duration would be expected and were not provided

Results were all presented as bar graphs. A dose -response curve for florpyrauxifen-benzyl  would be also be useful.

Please reformulate Discussion  section, following the same structure as in Results:

Efficacy of florpyrauxifen-benzyl on Eichhornia crassipes

Florpyrauxifen-benzyl accumulation in E. crassipes tissues

Florpyrauxifen-benzyl effect on water quality 

Conclusions need to be improved.

The references cited are relevant and in adequate number to support results and conclusions. I recommend to verify all the references numbers with Mendeley Reference Manager

Comments for author File: Comments.pdf

English language needs no improvement and it is in accordance with journal style. The name of active ingredients (a.i.) should start in small not capital  letters. Use scientific notation is requiered. 

Author Response

Dear Reviewer 3,

I have revised all your comments (file was attached), thank your for your comments.

Author Response File: Author Response.pdf