The Effect of Flooding on Evaporation and the Groundwater Table for a Salt-Crusted Soil

Round 1

Reviewer 1 Report

The paper has greatly improved from its first draft.

I have the feeling some more english polishing is needed, but English is not my native language....

Please see some comments in the attached file

Comments for author File: Comments.pdf

Author Response

I have the feeling some more english polishing is needed, but English is not my native language.... Answer : this manuscript has undergone English language editing by MDPI. Please see some comments in the attached file 1.SHOULD BE "precipitate' Answer: revised, line 40. 2.For sure Nachshon (myself) wasn't the first one to recognize it. You may say I studied it or something like that. Answer: I restate this sentence, line 41. 3.From my experience, the major reduction in evaporation is due to reduction of vapor diffusivity. I think that reports on reduction of capillary flow by the precipitated salt are more limited (but I may be wrong) Answer: I agree with this point, existing most studies reported that major reduction in evaporation is due to reduction of vapor diffusivity. Revised, line 48-49. 4.move the [23] after the 's Answer: revised, line 75. 5.move the [23] after the 's Answer: revised, line 79. 6.should be day (not days) Answer: revised, line 154. 7.So we see here a different behaviour for the different treatments in the day of flooding.... A point of each treatment is average of the three repetitions? I would add the errorbars. Answer: the fig 2 was added the error bars. Line 160. 8.I guess that also for conditions of no salt crust (pure water at the marriott bottle) the flooding would increase ER due to wetting of the upper surface. Can you comment on that? Estimate what is the role of this mechanism compare to removal of the crust? Answer: we added some discussion, line 315-321. 9.Didn't it push water back into the Mariotte? Answer: the valve was closed when the flood occurred, until the groundwater table recovery to initial water table, not allow push water back into the Mariotte.

Reviewer 2 Report

Review of the Manuscript titled: “The effect of flooding on evaporation and the groundwater table for a salt-crusted soil” (Ms. Ref. No. water-493367).

In the revised version of the MS, the authors have tried to address all issues raised in the previous version of the manuscript. However, the revised MS still contains major edits which authors should address before it is accepted for publication.

In addition, the English writing in the manuscript (including the cover letter) is very poor. I suggest the authors get editing help from full professional proficiency in English or from a native English speaker.

 

Followings are some comments for consideration:

 

1.      The percolation of flooding water is closely related to the initial soil water content. In this study, the soil column was saturated prior to imposing different treatments. The shallow groundwater table of 90 cm depth also contributed to maintaining the soil water content at a high level. Thus it is easy for the applied water to infiltrate through the soil column even though at a small amount (6 mm). The above mentioned condition should be taken into account when authors draw the conclusions of your study. Otherwise, it seemes no sense that flood water larger than 2 mm could recharge into groundwater in arid/hyper-arid areas.

2.      In Materials and Methods Section, the authors should clarify the principle of your experiment. You mentioned that the column weight was monitored to measure the weight loss because of evaporation. Then how about the weight of Mariotte bottle? Did the weight of Mariotte bottle remain unchanged?

3.      The Materials and Method Section was poorly written, the authors should reconstruct this part.

4.      Line 321-342: The authors have tried to address the existence of evaporation front, however, the effects of salt transport on the reformation of salt crust haven’t been explained clearly. Fig 4 illustrates the durations of salt crust reformation and flood ponding under different treatments. The flood ponding kept only several hours (0-7 h), while salt crust reformation lasted for about 17-100 hours. The differences were caused by the extents to which soil salt was flushed under different applied water amount. The more flood water was applied, the deeper the salt was leached, and the more time was needed to reaccumulate at soil surface along with the evaporation.

5.      The reply to 5 was only reflected in the covering letter, but also need to add in the main document.

6.      Line 13: Please add spaces between the numbers and units: 2 mm and 6 mm.

7.      Line 19: …, which indicated the existence …

8.      Line 24: another portion of the floodwater discharged into groundwater, …

9.      Line 41: precipitate

10.   Line 82: deduced

11.   Line 94: delete “and lies in the Tarim Basin”

12.   Line 97: In the Tarim River floodplain, …

13.   In Fig 2, “Flooding was applied on day 41”

14.   Line 163: 2-mm and 6-mm treatments are absent.

15.   In Fig 5, the right axis shows the changes of groundwater table?

16.   Line 221: at 20 cm depth

17.   Line 230: “did not show” or “showed no”

18.   Line 237: among them

19.   Line 329: It was the main reason …

20.   Line 380: the groundwater will be recharged which should not be neglected.

Author Response

I suggest the authors get editing help from full professional proficiency in English or from a native English speaker. Answer: this manuscript has undergone English language editing by MDPI. Followings are some comments for consideration: 1.The percolation of flooding water is closely related to the initial soil water content. In this study, the soil column was saturated prior to imposing different treatments. The shallow groundwater table of 90 cm depth also contributed to maintaining the soil water content at a high level. Thus it is easy for the applied water to infiltrate through the soil column even though at a small amount (6 mm). The above mentioned condition should be taken into account when authors draw the conclusions of your study. Otherwise, it seemes no sense that flood water larger than 2 mm could recharge into groundwater in arid/hyper-arid areas. Answer: Thanks for your suggestions, I revised, line 24-26, line 413-415. 2.In Materials and Methods Section, the authors should clarify the principle of your experiment. You mentioned that the column weight was monitored to measure the weight loss because of evaporation. Then how about the weight of Mariotte bottle? Did the weight of Mariotte bottle remain unchanged? Answer: The column and Mariotte bottle weight were monitored in a balance, line 127. That is to say, each column had a Mariotte bottle (Fig 1). if the water was not enough in the Mariotte bottle, the salt water was added, the time of add water was recorded, the added water amount was known by the balance data. 3.The Materials and Method Section was poorly written, the authors should reconstruct this part. Answer: I agree with this point, revised. The Materials and Method was divided three parts” 2.1 Study area, 2.2 Experiment Design and 2.3 Soil properties” 4.Line 321-342: The authors have tried to address the existence of evaporation front, however, the effects of salt transport on the reformation of salt crust haven’t been explained clearly. Fig 4 illustrates the durations of salt crust reformation and flood ponding under different treatments. The flood ponding kept only several hours (0-7 h), while salt crust reformation lasted for about 17-100 hours. The differences were caused by the extents to which soil salt was flushed under different applied water amount. The more flood water was applied, the deeper the salt was leached, and the more time was needed to reaccumulate at soil surface along with the evaporation. Answer: I added more content in discussion, line 306-315. 5.The reply to 5 was only reflected in the covering letter, but also need to add in the main document. Answer: revised, line 390-396. 6.Line 13: Please add spaces between the numbers and units: 2 mm and 6 mm. Answer: revised, line 13. 7.Line 19: …, which indicated the existence … Answer: revised, line 19. 8.Line 24: another portion of the floodwater discharged into groundwater, … Answer: revised, line :24-25. 9.Line 41: precipitate Answer: revised, line 40. 10.Line 82: deduced Answer: revised, line 80. 11.Line 94: delete “and lies in the Tarim Basin” Answer: revised. Line 93. 12.Line 97: In the Tarim River floodplain, … Answer: revised, line 96. 13.In Fig 2, “Flooding was applied on day 41” Answer: revised, fig 2,line160. 14.Line 163: 2-mm and 6-mm treatments are absent. Answer: revised, line164. 15.In Fig 5, the right axis shows the changes of groundwater table? Answer: yes, the right axis shows the changes of groundwater table, I add the information in caption of fig, line 216. 16.Line 221: at 20 cm depth Answer: revised, line222. 17.Line 230: “did not show” or “showed no” Answer: revised, line231. 18.Line 237: among them Answer: revised, line 238. 19.Line 329: It was the main reason … Answer: revised, line 361. 20. Line 380: the groundwater will be recharged which should not be neglected. Answer: revised, line 415.

Round 2

Reviewer 2 Report

I considered the paper can be accepted now.