Estimation of Critical Nitrogen Concentration Based on Leaf Dry Matter in Drip Irrigation Spring Maize Production in Northern China
, Jiangpeng Fu, Huifang Liu, Zhengzhou Li, Yu Lan, Xue Wei, Yongquan Zhai, Bingyuan Yun, Jianzhen Ma and Hao Zhang
Round 1
Reviewer 1 Report
In a context of climate change, a brief climatic description of the test sites would be appreciated.
It would be interesting to consider some climatic variables for anova analysis according to different climatic years of study.
Please insert some more descriptive information on crop management operations. Has it been tested with straight planting?
Author Response
In a context of climate change, a brief climatic description of the test sites would be appreciated.
Response: Thanks for your suggestion. We have added a brief climatic description for two experimental sites in the manuscript. The added contents were marked by red font. (Line 85-87).
It would be interesting to consider some climatic variables for anova analysis according to different climatic years of study.
Response: Thanks for your comment. We have analyzed the climatic data of three years in two experimental sites. The results showed that annual differences in rainfall and average temperature data are not significant (ns). Therefore, we did not add ANOVA detailed analysis in our manuscript. Please see the table.
Table The climatic data ANOVA analysis in two experimental sites of three years.
|
Year |
Site |
Factor |
Month |
||||||||||||||
|
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sept |
Oct |
Nov |
Dec |
|
|||||
|
2018 |
Pingjipu |
Rainfall |
0.0 |
8.1 |
21.6 |
75.2 |
74.6 |
19.6 |
159.8 |
165.3 |
16.7 |
20.3 |
4.6 |
0.0 |
|
||
|
Ave-temperature |
-6.2 |
-1.0 |
5.5 |
12.5 |
15.8 |
22.7 |
26.4 |
26.9 |
15.5 |
11.3 |
1.3 |
-4.0 |
|
||||
|
Yongning |
Rainfall |
0.0 |
9.3 |
18.1 |
65.3 |
81.6 |
22.3 |
165.9 |
146.5 |
39.8 |
14.6 |
0.0 |
0.7 |
|
|||
|
Ave-temperature |
-6.2 |
-1.7 |
6.2 |
11.6 |
16.2 |
23.1 |
26.7 |
26.6 |
15.8 |
11.6 |
2.2 |
-4.1 |
|
||||
|
2019 |
Pingjipu |
Rainfall |
4.9 |
0.0 |
3.7 |
12.0 |
16.9 |
2.4 |
116.2 |
87.9 |
24.0 |
8.2 |
3.9 |
0.1 |
|
||
|
Ave-temperature |
-7.3 |
-2 |
4.2 |
13.0 |
17.6 |
23.0 |
25.8 |
22.7 |
16.5 |
13.2 |
2.4 |
-1.0 |
|
||||
|
Yongning |
Rainfall |
1.2 |
13.5 |
45.6 |
27.8 |
35.2 |
75.6 |
81.6 |
123.4 |
38.9 |
89.4 |
4.6 |
0.4 |
|
|||
|
Ave-temperature |
-6.0 |
-1.6 |
4.6 |
13.2 |
18.1 |
23.5 |
25.4 |
23.6 |
17.2 |
13.0 |
3.5 |
-4.0 |
|
||||
|
2020 |
Pingjipu |
Rainfall |
0.6 |
13.5 |
17.2 |
23.6 |
33.0 |
34.6 |
81.6 |
46.9 |
41.0 |
18.5 |
0.0 |
0.0 |
|
||
|
Ave-temperature |
-5.6 |
-3.0 |
6.6 |
14.8 |
18.8 |
23.4 |
24.6 |
23.5 |
18.4 |
14.6 |
0.8 |
-2.3 |
|
||||
|
Yongning |
Rainfall |
0.0 |
15.7 |
40.4 |
29.6 |
32.4 |
79.5 |
92.7 |
63.9 |
48.0 |
93.4 |
0.0 |
1.5 |
|
|||
|
Ave-temperature |
-6.5 |
-2.8 |
6.2 |
13.8 |
19.2 |
22.8 |
25.6 |
24.6 |
19.5 |
13.6 |
2.5 |
-3.2 |
|
||||
|
ANOVA |
|||||||||||||||||
|
|
Year |
Site |
Year×Site |
||||||||||||||
|
rainfall |
ns |
ns |
ns |
||||||||||||||
|
Ave-temperature |
ns |
ns |
ns |
||||||||||||||
Please insert some more descriptive information on crop management operations. Has it been tested with straight planting?
Response: Thanks for your suggestion. We have supplemented crop management operations information in the manuscript. The revised contents were marked by red font. (Line 92-93, and Line 94-96).
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Manuscript entitled "Estimation of Critical Nitrogen Concentration Based on Leaf 2 Dry Matter in Drip Irrigation Spring Maize Production in 3 Northern China" by Biao Jia ,Jiangpeng Fu , Huifang Liu , Zhengzhou Li ,Yu Lan , Xue Wei Yongquan Zhai , Bingyuan Yun and Jianzhen Ma and Hao Zhang which offer a novel method for precisely managing N fertilizer application in spring maize cultivated under drip irrigation conditions. In this study, the author exposed to calibrate and validate LDM based Nc dilution curve in maize, and to compare the validated model with other crops Nc curve models and to evaluate its reliability in spring maize.
This article may be published with some modification and corrections.
Experimental design
The experimental designed is correct and maintain slandered protocol.
Validity of the findings
The experimental findings are valid and theme is very much important for the abiotic stress research community.
This article is interesting and have technical sounds and correctly performed. Provided article research theme is very much important for the China.
Title of the article is good. Abstract is well written but the introduction part lacks the state of the art and need an extensive improvement.
Material and methods were adequately described, there are some missing information so it should be rewrite with precise form. As for example, in line 88, the author mentions four irrigation amounts applied during the maize growing that was not written respectively. in line 90 the author mentions four percentage of Urea dissolved in drip irrigation was applied as N fertilizer but was not written respectively.
In the results section, please add one sentence at the end of each paragraph to conclude the whole paragraph to be more attractive for the readers. Also, in line 138-139 the authors should rewrite the ha-1 ranged correctly. in line 201, NNI values of TC19 and ND19 ranged was not also written respectively. in line 218, the authors did not write the coefficients of determination respectively as the mention.
Also, the discussion part need improvements and providing recent references on spring maize under drip irrigation conditions as mentioned above.
The last section of article is conclusion, in this section is too important to viewers and also researchers because that section is a road map of further research. When you draw a conclusion of the topic it should be maintain what’s your objective and Concluding remarks should be visionary and missionary. So, conclusion may be rewrite.
Author Response
Reviewer 2
Manuscript entitled "Estimation of Critical Nitrogen Concentration Based on Leaf Dry Matter in Drip Irrigation Spring Maize Production in Northern China" by Biao Jia, Jiangpeng Fu, Huifang Liu, Zhengzhou Li, Yu Lan, Xue Wei, Yongquan Zhai, Bingyuan Yun, Jianzhen Ma and Hao Zhang which offer a novel method for precisely managing N fertilizer application in spring maize cultivated under drip irrigation conditions. In this study, the author exposed to calibrate and validate LDM based Nc dilution curve in maize, and to compare the validated model with other crops Nc curve models and to evaluate its reliability in spring maize.
This article may be published with some modification and corrections.
Response: Thank you very much for your approval of our work.
Experimental design
The experimental designed is correct and maintain slandered protocol.
Response: Thank you very much for your approval of our work.
Validity of the findings
The experimental findings are valid and theme is very much important for the abiotic stress research community.
Response: Thank you very much for your approval of our work.
This article is interesting and have technical sounds and correctly performed. Provided article research theme is very much important for the China.
Response: Thank you very much for your approval of our work.
Title of the article is good. Abstract is well written but the introduction part lacks the state of the art and need an extensive improvement.
Response: Thank you very much for your approval and suggestion. We have revised the introduction in the manuscript. The revised contents were marked by red font. (Line 39-40, line 49-51, line 56-57, line 62-68, line 70-71, and line77-80).
Material and methods were adequately described, there are some missing information so it should be rewrite with precise form. As for example, in line 88, the author mentions four irrigation amounts applied during the maize growing that was not written respectively. in line 90 the author mentions four percentage of Urea dissolved in drip irrigation was applied as N fertilizer but was not written respectively.
Response: Thanks for your suggestion. We have supplemented more information (four irrigation amounts applied and four percentage of Urea dissolved) in the part of material and methods in the manuscript. The revised contents were marked by red font. (Line 102-105). We have revised other content in the manuscript. (Line 107-109).
In the results section, please add one sentence at the end of each paragraph to conclude the whole paragraph to be more attractive for the readers. Also, in line 138-139 the authors should rewrite the ha-1 ranged correctly. in line 201, NNI values of TC19 and ND19 ranged was not also written respectively. in line 218, the authors did not write the coefficients of determination respectively as the mention.
Response: Thanks for your suggestion. We have supplemented the information in the part of the results section in the manuscript. (Line 153-157, line 163-167 and line 223-225).
Also, the discussion part need improvements and providing recent references on spring maize under drip irrigation conditions as mentioned above.
Response: Thanks for your suggestion. We have added recent references and adjusted reference numbers in the manuscript. The revised references were marked by red font. (references 36-41, 43, 44, 46-50, 54, and 55), and we have revised other references (reference 1, 5, 22, 27, 29, 30 and 34). The discussion part improved contents were marked by red font. (Line 265-268, line 309-310 and line 312-320).
The last section of article is conclusion, in this section is too important to viewers and also researchers because that section is a road map of further research. When you draw a conclusion of the topic it should be maintain what’s your objective and Concluding remarks should be visionary and missionary. So, conclusion may be rewrite.
Response: Thanks for your suggestion. We have rewritten the conclusion in the manuscript. (Line 337-350).
Author Response File: Author Response.pdf
Reviewer 3 Report
I think that this paper has incorporated a lot of data well and has done a good job of the analysis of that data. There needs to be more clarification in the introduction and discussion and conclusion to make this paper stronger and the objectives and findings clearer. The application and feasibility section could be less general and focus more directly on what this work is showing.
Line 32: Do you mean ammonia volatilization instead of ammoniation? Seems like a larger loss pathway.
Line 37: comma splice after management
Line 41: "and" instead of "as well as"
Line 43: need comma before especially
Line 47: commas are incorrectly used here—or sentence structure is confusing. Reword and check grammar on “, and can thus,”. Could be two sentences for clarity.
Line 58: Remove “Besides,” and start with “Leaves are extremely….”
Line 58-64: Starting “For instance….” until “…evaluating the status of crop growth” is confusing. Does dry matter accumulation increase even at luxury levels of uptake? This paragraph needs some work on clarity. It seems contradictory as how it is worded now and the LNC measurement would be a better approach than LDM.
Line 64: LDM and PDM (line 48) have both been established for rice, wheat and other crops – how do these impact the relationships to the Nc dilution curves? Why would one method be chosen over the other? Does this relate back to line 58-64?
Line 77: Which N fertilizer?
Table 1: How were these determined? pH? Organic matter? TN? Available N? Available P? Available K? Need citations and methods for extractions of this.
Line 126: Was the maximum LDM always the from highest fertilizer application? Has this approach been previously used in the literature?
Figure 1: Could you ID or label the significant differences for one or two of the growth stages in this graph (all would be too messy) but from looking at the graphs it is surprising that you would see significant differences in the N3 from the N4 and N5. Is that only for a particular growth stage?
Line 173: missing a word—“….the LDC does not be significantly reduced”?
Figure 4: is the dotted line a 1:1 line? Can you label that? Or put in Figure 4 description.
Figure 5: Nice graph—am curious if you can say it is cultivar or if it is location? Since cultivars were grown at different sites? Maybe mention different locations and different initial soil characteristics as well.
Figure 6: I am not sure if this is needed this paper or is if adds. More mention of this in the results and discussion is needed to keep this information relevant.
Line 240: This sentence is confusing—"a ?means? the LNC”…? Reference equation 1 in this sentence
Line 267/268: Introducing Nmin and Nmax abbreviations without previous explanation that I could find.
Author Response
Reviewer 3
I think that this paper has incorporated a lot of data well and has done a good job of the analysis of that data. There needs to be more clarification in the introduction and discussion and conclusion to make this paper stronger and the objectives and findings clearer. The application and feasibility section could be less general and focus more directly on what this work is showing.
Response: Yes, you are right. Thanks for your suggestions. We have revised the introduction (Line 39-40, line 48-51, line 56-57, line 62-68, line 70-72, and line77-80) and discussion (Line 255-256, line 265-268, line 292-294, line 309-310, and line 312-320) and conclusion (Line 337-350) in the manuscript. The revised contents were marked by red font.
Line 32: Do you mean ammonia volatilization instead of ammoniation? Seems like a larger loss pathway.
Response: Thanks for your comment. It should be “ammonia volatilization”, we have revised it in the manuscript. The revised contents were marked by red font. (Line 32-33).
Line 37: comma splice after management
Response: Yes, you are right. Thanks for your comment. We have revised it in the manuscript. The revised contents were marked by red font. (Line 37).
Line 41: "and" instead of "as well as"
Response: Thanks for your comment. We have revised it in the manuscript. The revised contents were marked by red font. (Line 37).
Line 43: need comma before especially
Response: Thanks for your comment. We have revised it in the manuscript. The revised contents were marked by red font. (Line 44).
Line 47: commas are incorrectly used here—or sentence structure is confusing. Reword and check grammar on “, and can thus,”. Could be two sentences for clarity.
Response: Thanks for your comment. We have separated it into two sentences in the manuscript. The revised contents were marked by red font. (Line 48).
Line 58: Remove “Besides,” and start with “Leaves are extremely….”
Response: Thanks for your comment. We have revised it in the manuscript. (Line 61).
Line 58-64: Starting “For instance….” until “…evaluating the status of crop growth” is confusing. Does dry matter accumulation increase even at luxury levels of uptake? This paragraph needs some work on clarity. It seems contradictory as how it is worded now and the LNC measurement would be a better approach than LDM.
Response: Yes, you are right. Thanks for your comment. We have revised it in the manuscript. The revised contents were marked by red font. (Line 62-68).
Line 64: LDM and PDM (line 48) have both been established for rice, wheat and other crops – how do these impact the relationships to the Nc dilution curves? Why would one method be chosen over the other? Does this relate back to line 58-64?
Response: Yes, you are right. Thanks for your comment. We have supplemented and revised it in the manuscript. The supplemented and revised contents were marked by red font. (Line 70-71).
Line 77: Which N fertilizer?
Response: Yes, you are right. Thanks for your comment. We have revised it in the manuscript. N fertilizer was applied as urea (Line 88)
Table 1: How were these determined? pH? Organic matter? TN? Available N? Available P? Available K? Need citations and methods for extractions of this.
Response: Yes, you are right. Thanks for your comment. We have supplemented citations for it in the manuscript. (Line 98)
Line 126: Was the maximum LDM always the from highest fertilizer application? Has this approach been previously used in the literature?
Response: Yes, you are right. Thanks for your comment. The maximum dry matter of maize leaves in the whole growing season. It wasn’t always the highest fertilizer application. Say sorry, that is, our description was not clear enough. We have revised it in the manuscript. (Line 137-138, and line 141-142).
Figure 1: Could you ID or label the significant differences for one or two of the growth stages in this graph (all would be too messy) but from looking at the graphs it is surprising that you would see significant differences in the N3 from the N4 and N5. Is that only for a particular growth stage?
Response: Yes, you are right. Thanks for your comment. We have re-charted the Figure 1 (Line 169) and added the significant differences label in the manuscript. (Line 172-174).
Line 173: missing a word—“….the LDC does not be significantly reduced”?
Response: Yes, you are right. Thanks for your comment. We have added a word in the manuscript. (Line 196)
Figure 4: is the dotted line a 1:1 line? Can you label that? Or put in Figure 4 description.
Response: Yes, you are right. Thanks for your comment. The dotted line was a 1:1 line. We have added label of 1:1 line and fitted line label in figure 4 in the revision manuscript. (Line 218)
Figure 5: Nice graph—am curious if you can say it is cultivar or if it is location? Since cultivars were grown at different sites? Maybe mention different locations and different initial soil characteristics as well.
Response: Thank you very much for your approval of our graphs, and thanks for your comment. Yes, you are right. We have revised in the manuscript, and we have analyzed initial soil characteristics (See Table 1) in two locations (Line 98).
Figure 6: I am not sure if this is needed this paper or is if adds. More mention of this in the results and discussion is needed to keep this information relevant.
Response: Yes, you are right. Thanks for your comment. We have added discussion information relevant in the manuscript. (Line 312-320).
Line 240: This sentence is confusing—"a ? means? the LNC”…? Reference equation 1 in this sentence
Response: Yes, you are right. Thanks for your comment. We have revised the sentence in the manuscript. (Line 265 and 268).
Line 267/268: Introducing Nmin and Nmax abbreviations without previous explanation that I could find.
Response: Yes, you are right. Thanks for your comment. We have revised it in the manuscript. Abbreviation Nmin that is, the lower limit curve and Nmax that is, the upper limit curve. (Line 292-294 and Line 368-369).
Author Response File: Author Response.pdf
