Optimal Straw Retention Strategies for Low-Carbon Rice Production: 5 Year Results of an In Situ Trial in Eastern China
, Huifeng Sun 1,2,3,†, Xianxian Zhang 1,2,3, Jining Zhang 1,2,3 and Sheng Zhou 1,2,3,*
Round 1
Reviewer 1 Report
Manuscript ID: agronomy-2400426
This manuscript evaluated the effects of different fore-rotating crop straw retention strategies on rice paddy carbon budget through a field experiment. In-situ CH4 emission and soil physicochemical properties were detected for continuous 5 years. It is generally an interesting research with sufficient data, and has significant importance for sustainable and low-carbon agricultural production. It can be considered for published in Agronomy after minor revisions.
The following questions should be addressed.
1. It should be annual rather than seasonal cumulative emissions of CH4 in Fig. 2. Accordingly, “seasonal dynamics” might be replaced by “dynamics”.
2. Why did the authors choose two-factor repeated measures analysis in Table 3?
3. The caption of table 5 was the same to table 3. It should be corrected.
4. What is the temperature in Fig.5? How did you obtain the data of this index?
Author Response
Please see the attachment.
Author Response File: 
Author Response.docx
Reviewer 2 Report
This manuscript deals with the impact of wheat straw return to soil on soil carbon sequestration and methane emissions in a wheat-rice rotation during a five-years experimental period. Authors conclude that biochar derived from wheat straw was superior in enhancing soil carbon sequestration and minimizing methane emissions compared to return of raw wheat straw.
The conclusions are relatively robust, because of the 5-years experimental period. The experimental design and the GHG measurements are sound. The type of study fits also within the scope of the journal. The manuscript is written in understandable English language.
I have only a few comments;
· Please include Figure 4
· Please justify the straw and biochar application rates
· Please describe clearly what you did with the rice straw and include results of the wheat yield
· Please address the minor comments below
L48: what is “fore-rotating crop straw”?
L90: please justify the application rates of straw and biochar. It seems that not all straw was returned. And how much straw was needed to produce 1 ton of biochar?
L92: why did you include slow release fertilizer as treatment? What is the relationship with soil carbon sequestration or CH4 emissions?
L96: do you mean that rice straw and biochar derived from rice straw was applied before the wheat sowing?
L122: why only the layer 0-10 cm?
L164: sentence not clear; please edit
L203: there is no Figure 4 in the manuscript.
L207: please report also on the wheat yields
Few suggestions included in my report
Author Response
Please see the attachment.
Author Response File: Author Response.docx
