Cover Crops Enhance Soil Properties in Arid Agroecosystem despite Limited Irrigation
Round 1
Reviewer 1 Report
Useful research topic and the manuscript is well written, clearly presents the previous literature, background justification is well done, the problem is well described and justified. The experiment was conducted well. This information would have some value for the growers. The tables and figures are acceptable. The manuscript contains some information that would be of interests of Agronomy readers. The research presented is of scientific merit and that scientific community would benefit from knowledge that would be gained from this manuscript being published.
Author Response
Thank you so much for taking out time to review our manuscript.
Reviewer 2 Report
Revision of manuscript agronomy-1709405
Abstract (and p2, line93) –
The study aimes to assess the influence of irrigation to produce a sufficient CC biomass to ameliorate soil properties. What does sufficient mean? Do you have an estimation of the amount of biomass needed?
Materials and methods
p3, lines 117-125-The description of experimental set up is not clear. It seems that fallow is the only non-irrigated treatment while all the other 4 CC treatments received water. If it is so, 80 seems to be an inconsistent number of replicates. By your description emerges that only 52 replicates were performed (4 replicates of non-irrigated fallow + 4 treatments (barley CC +pea CC + mustard CC + mix of the three CCs) x 3 irrigation rates x 4 replicates each CC treatment). Was fallow plot also irrigated? Were the other CC plots not irrigated?
p4, line 135 - kg ha-1 should be replaced with kg ha-1. Lines 169-171- I find DASD a redundant acronym since you do not mention it in any other part of the manuscript. line 170 – specify the range of sieves used to assess MWD. I’m not sure you can consider only aggregates >2mm as large aggregates. To my knowledge, macroaggregates are already considered those with diameter>0,25 mm. Further you should specify the unit, or the amount of soil tested (MWD was determined on 1 g of dry soil? 1 kg of dry soil? m2 of soil?). line 176 – why the rainfall energy was set up at 2.5 J? lines 175-176 - the experiment was set up in arid conditions, why did you judge better to determine aggregates stability by simulating rain fall instead of wind conditions? line 184 – phosphorous instead of Phosphorous. Also describe methods of analysis used for pH, potassium and SOM.
Results
p5, lines 203-204- reference 19 should be cited in the discussion section, lines 213-218 – provide a possible reason that can explain the less biomass produced during 2020 in comparison to 2019 at Los Lunas. If I’m not wrong (based on a rough calculation), it seems that rain was generally more abundant in 2019-2020 than in 2018-2019 (figure 1) and CC underwent same irrigation treatments during the two years.
p6, lines 242-245 – provide an explanation about MWD results of barley 2019. Despite the very high amount of biomass produced (till up 14,692 kg ha-1 as total biomass), you measured the lowest MWD if compared with fallow. Then you observed an inverse trend from 2020 data (high MWD, but lower biomass)
p9, line 305- reference 19 should be cited in discussion section.
Discussion
p10, line 328. I would suggest the authors to also consider the influence of the living mulching acting as a soil particles aggregation factor, because of roots development and exudates release. Consider that incorporation of CC (they were disked twice), if on one side allows for a better mineralization of residues, by the other determines aggregates breaking.
Conclusion
p12, line 415-416 this sentence is in contrast with what you have stated in p11 lines 380-381 and 400-401. The observed increase of 0.5% of SOM is difficult to consider a long-term result, matter of fact that peas, as you stated, release very easy mineralizable debris that only scarcely can contribute to stabilize organic matter in soil.
Tables and Figures
Figures are not easy legible. Try to increase the font-size.
Table 1 is puzzling the reader. Try to make it more easily to read. Replace mg kg-1 with mg kg-1
Figure 4 seems to be redundant with respect to what already reported along the text. Maybe it could be more informative to have a figure regarding corn yield and to explain the reason of the different productions obtained (e.g. Los Lunas had 4 times yield in CC treatments than in fallow) despite the overall same total N applied on the basis of the rate of N already available in each treatment.
Author Response
Please see the attachment.
Author Response File: 
Author Response.docx
