Contribution of Roots and Shoots of Three Summer Cover Crops to Soil C and N Cycling Post-Termination
Round 1
Reviewer 1 Report
Comments and Suggestions for Authors- The author should provide more main chemical properties of the experimental plots, rather than the selected parts, such as SOC N.
2.Line 166, What is the depth of excavation? What is the depth of excavation for the remainder of the CCs plants? The root systems of the CCs plants should not be the same.
- Due to the differences of planting period and environment during 2022 and 2023, the biomass should be listed as an annual value rather than an average. Meanwhile, significance analysis should be conducted.
- The significance among different CCs plants were not indicated in Figure 4 and 5.
5.The author should supplement the release rate of mass, C and N. The release rate can better characterize the decomposition than the residues. Meanwhile, the relationship between the decomposition rate and C: N should be analyzed.
6.Line 459-460, The results of cannot quantify their contributions of carbon (C) and nitrogen 459 (N) to the soil. And The title should be revised. The author did not provide the results of the soil.
Author Response
Please see the attached file
Author Response File: Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThis study investigates the effects of three summer cover crops (oat, buckwheat, pea) on soil C and N cycling through biomass allocation, decomposition dynamics, and nutrient release. The research addresses a critical gap in understanding root-shoot contributions to soil health in short-season systems, particularly in the Northeast U.S. context. The findings provide valuable insights into cover crop selection for double-cropping systems, major revisions are as follows.
1.The keywords are too numerous and need to be condensed.
- Clarity of Hypotheses: The abstract states a hypothesis that root and shoot decomposition rates may not differ significantly in short growing periods under conventional tillage. However, the introduction also mentions a second hypothesis about decomposition dynamics varying by species. These hypotheses should be explicitly separated and framed more clearly to guide the reader.
- Table 1: Calcium, magnesium, and sulfur are not macronutrients. Is the data in Table 1 total content or available content? What are the reasons for the large differences in data between the two years? Please check.
- Table 3 Planting Date Variability: The study notes a 17-day delay in planting between 2022 (June 23) and 2023 (July 10), leading to shorter growth duration in 2023 (42 days vs. 60 days). How did this affect biomass and nutrient allocation? Were differences between years statistically accounted for in the analysis? Clarify whether results are presented as combined averages or if year-specific trends are meaningful.
- Line 163 0.5 m2 should be 0.5m2
- What are the differences in the requirements for root excavation depth among different cover crops? How can author ensure that all roots are completely excavated?
- Line 171, When setting up the litter bag experiment, the authors should specify in detail whether the roots and shoots are fresh samples or oven-dried samples, and what the cutting length is.
- Line 194 The use of log-transformation for decomposition data is mentioned, but the rationale for this approach (e.g., normality assumptions) is not explained. Provide a brief justification in the methods section.
- The data in the article should be presented as mean plus or minus standard deviation, and the results of statistical analysis should be provided.
- In the discussion section, the authors should condense the content and divide it into different subsections for separate discussions.
- Deepen Discussion of Mechanisms: Link C:N ratios, lignin content, and environmental factors (e.g., GDD, precipitation) to decomposition rates.
- The authors propose that different carbon-to-nitrogen ratios (C:N ratios) influence mineralization and immobilization processes. However, the manuscript currently lacks supporting data on microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN). It is therefore recommended to supplement the study with relevant experimental data to validate this hypothesis.
Author Response
Please see the attached file
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Comments and Suggestions for AuthorsThe author has made good modifications to the questions raised, and it is recommended to accept MS.