Whether Increasing Maize Planting Density Increases the Total Water Use Depends on Soil Water in the 0–60 cm Soil Layer in the North China Plain
Round 1
Reviewer 1 Report
Title: Needs modification (in the 0-60 cm in the North China plain, rewrite to avoid in the word twice)
Abstract: good
Introduction: Give hypothesis with proper background in L 57-63
Bring Figure 2, Table 1 and Table 2 and Table 3 under result section
Figure 3-5: Different lower case letter means significant difference within a date? Plz specify
Table 4, 5 give the Least significant difference (LSD) value of ANOVA where ever the effects (Y, P, Y x P) are significant
Improve the english in the article
Author Response
Point 1: Title: Needs modification (in the 0-60 cm in the North China plain, rewrite to avoid in the word twice).
Response 1: We would like to thank you for your valuable reviews. We added two words (soil layer) before the second “in”, the revised title is “ Whether increasing maize planting density increases the total water use depends on soil water in the 0-60cm soil layer in the North China Plain”. If the title needs modification again, I hope I have a chance to revise it again based on your second review.
Point 2: Introduction: Give hypothesis with proper background in L 57-63.
Response 2: We followed your suggestions, and added the background in the newly revised manuscript as follows:
Soil water deficits are not a new or becoming concern but has been there for centuries. Due to the high variability of seasonal precipitation in the NCP, drought is often a limiting factor for maize production. Under these conditions, irrigation is often required to supplement soil water; the large amount of water used for agriculture had led to an increasing depletion of groundwater resources in the NCP, with groundwater levels declining at a rate of 0.5-1.0 meters per year, which had caused a number of serious environmental and ecological problems in the region . These problems are forcing irrigators in the NCP to look for ways to conserve water and improve WUE.
Point 3: Bring Figure 2, Table 1 and Table 2 and Table 3 under result section
Response 3: Thank you for your valuable reviews, but I'm not sure I fully understand your meaning of "result section". According to the structure of the manuscript content, I adjusted the position of some Figures and Tables. If I misunderstood what you mean, I hope I have a chance to revise it again based on your second review.
Point 4: Table 4, 5 give the Least significant difference (LSD) value of ANOVA where ever the effects (Y, P, Y x P) are significant
Response 4: According to your suggestion, we have given the least significant difference (LSD) value of ANOVA in the newly revised manuscript.
Point 5: Improve the English in the article
Response 5: Apologies for the less-than-qualified English of this manuscript. Before submitting the manuscript to the journal, we have found an agency that may not be so much professional to help us improve the English. According to your suggestion, we found another person who was good at English to help us improve our English expressions in the newly revised manuscript
Reviewer 2 Report
The manuscript’s (MS) topic deals with the effects of maize planting density in the China on transpiration, ET, soil water content, grain yield, and yield components. In my opinion, reading the MS is enjoyable, it has a relevant insight and novelty for an international scientific journal such as Sustainability.
I have read and examined all the manuscript and have only few comments as fallowing:
The shape of the plant growing area in 2018 is different from 2019&2020. Because the row spacings and planting spacings are different. The shape of the growing area is an effective factor on the parameters evaluated in this research. Optimum growing shape is circle in theory and the closer the growing area shape is to circle, the better. I believe that this difference have a potential to effect the results. This situation should be discussed in MS.
Which equipments were used for soil loosening? (line 97)
Explanation for the first mention of abbreviations is needed. Avoid using abbreviation in Abstract.
Author Response
Point 1: The shape of the plant growing area in 2018 is different from 2019&2020. Because the row spacings and planting spacings are different. The shape of the growing area is an effective factor on the parameters evaluated in this research. Optimum growing shape is circle in theory and the closer the growing area shape is to circle, the better. I believe that this difference have a potential to effect the results. This situation should be discussed in MS.
Response 1: Thank you for your kind remindings, your suggestions inspired me a lot.
Many studies have shown that even at the same planting density, different row spacing can affect the canopy structure, which in turn affects the crop growth environment and yield. This may be the main reason why the number of effective spikes per plant in 2018 was significantly different from the other two years, and we discussed it in Section 4.3. At your reminder, I carefully checked the growth process of maize again, the stem profile of corn is similar to oval, and the leaves of maize tend to grow to the sides rather than in a circular shape. This may be one of the reasons why maize is usually planted in wider row spacing. If the discussion is not sufficient, I hope I have a chance to revise it again based on your second review.
Point 2: Which equipments were used for soil loosening? (line 97)
Response 1: Soil loosening was performed by a tractor mounted scarifier, and we addressed this issue in the newly revised manuscript
Point 3: Explanation for the first mention of abbreviations is needed. Avoid using abbreviation in Abstract.
Response 1: Thank you for your kind reminding, we checked the full text and addressed this issue in the newly revised manuscript
Author Response File: 
Author Response.pdf
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.
