Effects of Irrigation and Nitrogen Application on Soil Nutrients in Triploid Populus tomentosa Stands

Round 1

Reviewer 1 Report

I have revised the manuscript ” Effects of Irrigation and Nitrogen Application on Soil Nutri- ents in Triploid Populus tomentosa Stands” The topic of this paper is of paramount importance when considering the fact that irrigation combined with nitrogen applikation is a good way to increase yield of plant also including trees and has effects on soil nutritients . The topic is closely falls within the aims and scope of the journal. The data provided are sufficient and the statistical analysis of the results is well presented. The discussion of results focus on the main points while justification of the findings are well supported by references. Below, I am presenting my comments of the manuscript:

General comments:

2. Materials and Methods

2.1. Study Site

It would be  well to present the meteorological conditions in the years of research in the form of climatograms

2.4. Soil Sampling and Analysis

I sugest write what instrument was used to taken soil samples.

3. Results

Under the tables and figures, authors should provide explanations of all abbreviations in tables and graphs TN, SOM, AP, AK, C/N, W1, W2, W3, N0, N1, N2, N3…

Line 194. And 2020: missing spaces.

Line 359. Pathak, P. & Reddy, A. S.:  should be Pathak and Reddy?

Line 360. one dot too many

Line 392.  240–272 mg·kg⁻¹ : missing spaces.

Author Response

Thanks for your constructive comments concerning our manuscript. Please see the attachment. Thank you again for your affirmation of this manuscript.

Author Response File: Author Response.docx

Reviewer 2 Report

 

The evaluated manuscript deals with the issue of understanding the response of soil nutrients to long-term water-fertilizer coupling conditions to improve the management and use efficiency. The authors measured tree height /Populus tomentosa/ and the diameter at breast height and analysed the chemical properties of the soil in 0–40 cm from 2007 to 2020. In conclusions authors state that with the increase in nitrogen application rate, the contents of total nitrogen and nitrate-nitrogen in the soil rose significantly, while the contents of available phosphorus and available potassium decreased. Through long-term monitoring, they found that optimizing irrigation and nitrogen application system can effectively improve soil fertility. In my opinion, manuscript is written at a good level, it has the required structure in terms of scientific publication as well as a sufficient number of cited literary sources /64/. The abstract and keywords are consistent with the content of the article. I can state that after studying the article, I do not have any serious negative comments. Manuscript is written at a good level, I recommend this article „Effects of Irrigation and Nitrogen Application on Soil Nutrients in Triploid Populus tomentosa Stands“ for publishing.

Author Response

Thank you very much for your affirmation of this manuscript. I will further improve my manuscript according to the requirements of the journal. Your affirmation has played an important role in building my confidence. Thank you again for your careful review of this manuscript.

Reviewer 3 Report

Please consider the following recommendations:

lines 21-23: „By maintaining the soil water content above different field water holding capacities (45%, 60%, and 75%) and different nitrogen  application rates (0.0, 101.6, 203.2, and 304.8 kg·hm−2).” incomprehensible, it should be rephrased

line 23: „DBH” any abbreviation should be explained first time when used in the manuscript

line 48: “affecting factors forest growth” I suggest to be changed with „factors affecting forest growth”

line 59: “Yu et al.” the year of publication should not be mentioned? There are many other similar citations

line 67: „H.squamatum” I suggest to be replaced by „Helianthemum squamatum”

line 73: „Xiang, et al.” does not appear in the References

lines 76-78: “Long-term application of chemical and organic fertilizers increases the content of total phosphorus, available phosphorus, inorganic phosphorus, and organic phosphorus in the soil to varying degrees.”, please provide a citation for this statement

lines 131-132: “From 2007 to 2020, fertilization was applied at the end of May in amounts of 1/3. The 131 remaining fertilizer was applied at the end of June and July.” if the rates were similar for the next two months, it could be specified

line 204: Table 1, the abbreviation of analyzed parameters (SOM, TN, AP, AK, C/N) should be explained in the note of the table. I recommend that all abbreviations used in all tables and figures to be explained

            There are some comments on data that do not appear in tables or figures (e.g. percentage/multiplication expressions of different records for the analysed parameters; e.g. lines 232, 234, 246. “…it decreased by 19%...;  …were 1.2 and 1.3 times those at W1 (45%).”) – meaning that they should be calculated by reader?

line 291: “Pinus Tabulaeformis” not “Pinus tabuliformis”?

line 291-292: „Bupleurum Chinense” not „Bupleurum chinense”?

line 312” „Larix Principis- Rupprechtii” not „Larix principis-rupprechtii”?

The aim of the study should be clearly stated in the abstract.

Conclusions should reveal the main findings of the research. Conclusions section has a too large extent; moreover some of the results are repeated.

Author Response

Thanks for your constructive comments concerning our manuscript. Please see the attachment. We are very grateful to Reviewer for reviewing the paper so carefully.

Author Response File: Author Response.docx