The Fate and Distribution of Microalgal Nitrogen When Applied as an Agricultural Soil Fertiliser and Its Effect on Soil Microbial Communities
Round 1
Reviewer 1 Report
Reviewer’s comments on phycology-1788742
This study described the fate and distribution of microalgal nitrogen (Chlorella vulgaris) using 15N tracer experiments when applied as an N-fertilizer for wheat. The authors also investigated microbiological communities in C. vulgaris and urea-treated soils and control soils. All experiments are precise and data interpretation is appropriate. I recommend that this manuscript is accepted for publication in Phycology. My minor comments are as follows:
(1) Table 1 is somewhat incomprehensible. It would be better to separate “Initial soil (control)” from “Mixed algae” and ”Urea”. The latter two items are not “soil”.
(2) Line 316. “15N” should be “15N (superscript 15)”.
Author Response
Thank you for your comments. We have made both minor alterations as follows:
1. Reviewer: Table 1 is somewhat incomprehensible. It would be better to separate “Initial soil (control)” from “Mixed algae” and “Urea”. The latter two items are not “soil”.
Response: We have split table 1 into two tables: one table showing only the initial soil characteristics (Table 1) and another table showing the total carbon and nitrogen concentrations in soil and N treatments (Table 2).
2. Reviewer: Line 316. “15N” should be “15N (superscript 15)”.
Response: We have gone through the manuscript and have changed all 15N to 15N (superscript 15).
Reviewer 2 Report
The topic of this manuscript is new and very interesting. The experiments are well conducted. Anyway, I suggest some modifications: first of all, a general reorganization of data in the figures and then of the results section.
3.1 N concentrations in soil (figs 3a, b, c, d)
3.1.1 N concentrations in plants (fig 2)
Minor comments:
Fig.1 in panel Source correct agricultural
p2 line 59 add TN (Total Nitrogen)
mL and not ml throughout the text
p3 line 122 correct h and not hr (and throughout the text)
p5 line 174 a parenthesis is missing
In Discussion section references to figures must be eliminated
Author Response
Thank you for your comments. We have made alterations as follows:
- Reviewer: A general reorganization of data in the figures and then of the results section.
3.1 N concentrations in soil (figs 3a, b, c, d):
3.1.1 N concentrations in plants (fig 2):
Response: Figure 3 shows N concentrations in soils. We have labelled the left column in (a,c,e) “Soil with wheat” and right column (b,d,f) “Fallow Pots” for clarity. In the Figure legend, we have made this more clear in the name “Nitrogen measurements in soil” the blue lines (control) and green lines (algae treatment) are added. Section 3.1 ‘N concentrations in plant and soil pools' serves as an introduction to the section, but to avoid confusion, we have now removed any reference to Figure 3 in this section. This is then followed by two sections that go on to separately present the results of the soil N concentrations in plants (Section 3.1.1N concentrations in plants) and subsequent sections which go on to describe TN, NH4+ and NO3-concentrations in bulk soil.
2.Reviewer: Fig.1 in panel Source correct agricultural
Response: We have corrected the typo in Figure 1 from agrcultural to agricultural
3. Reviewer: p2 line 59 add TN (Total Nitrogen)
Response: We have added 'Total Nitrogen' to what is now line 60
4. Reviewer: mLand not ml throughout the text
Response: We have corrected all ml to mL
5. Reviewer: p3 line 122 correct h and not hr (and throughout the text)
Response: We have corrected all hr to h
6. Reviewer: p5 line 174 a parenthesis is missing
Response: We have added a parenthesis to what is now line 187
7. Reviewer: In the Discussion section references to figures must be eliminated
Response: We have removed all references to figures and tables in the Discussion section
