Earthworm Abundance Increased by Mob-Grazing Zero-Tilled Arable Land in South-East England
Round 1
Reviewer 1 Report
1. 1. First of all, I apologize English is not my native language. I hope you will understand my well-intentioned comments.
2. The extension of the term conservation tillage with regenerative agriculture is to be welcomed. The main shortcoming of the paper is that only one sampling was conducted in October. Based on JUST one sampling, it is very difficult to conclude something scientifically. This is the current state, by no means a long-term scientific research. What would happen to the number of earthworms if the sampling was done in the spring and not in the fall? Or another vegetation year that was rainier or drier?
2.1. Site description: Define for which period the average annual values of temperature and precipitation are stated? Obligation, in this subchapter insert a few sentences about the soil type and its basic chemical characteristics - soil pH). Last sentence in this subchapter switch u 2.2. Field treatments - Direct seed sowing was implemented by a John Deere® (Langar, Not tinghamshire, UK) 750A direct drill.
2.3. Earthworms were sampled in the autumn (October) – which year, please explain WHY in this moment
2.4. It is mandatory to insert the data into the results of the research on the CN relationship in the soil on the individual three treatments.
Cited, on page 150: Total earthworm counts were highest in the ZTMG treatment, after that on page 189 cited: Soil moisture levels were significantly different between all treatments (Table 2), with the PG being the wettest area, and the ZTMG the driest. I can’t believe???? The number of earthworms is fundamentally dependent on soil moisture, regardless of the method of soil management (conservation or regenerative agriculture). If the soil is drier, earthworms migrate deeper into the soil solum. Can you clarify this? This is crucial point of this paper. By the way, in paper present only one soil sampling in October.
Author Response
First of all, I apologize English is not my native language. I hope you will understand my well-intentioned comments.
Thank you for the constructive comments, your English is perfectly understandable.
The extension of the term conservation tillage with regenerative agriculture is to be welcomed. The main shortcoming of the paper is that only one sampling was conducted in October. Based on JUST one sampling, it is very difficult to conclude something scientifically. This is the current state, by no means a long-term scientific research. What would happen to the number of earthworms if the sampling was done in the spring and not in the fall? Or another vegetation year that was rainier or drier?
Fair comment. It is acknowledged that there is one sampling period and that this does not represent a long term monitoring project. The manuscript discussion acknowledges the need for further sampling ‘Future work to evaluate the temporal impact of livestock grazing over multiple years and at different times during the season, its duration and the length of the grass-clover ley recovery period would be of further interest. Also in the conclusions 'This study evaluates a single snapshot in time. A further assessment of how the presence of livestock at different times during the season influences earthworm distribution, coupled with variation in grazing extent and how long the grass-clover ley is given to recover monitored over subsequent years represents important future work.'
2.1. Site description: Define for which period the average annual values of temperature and precipitation are stated?
Added to section 2.1
Obligation, in this subchapter insert a few sentences about the soil type and its basic chemical characteristics - soil pH).
Added to section 2.1
Last sentence in this subchapter switch u 2.2. Field treatments - Direct seed sowing was implemented by a John Deere® (Langar, Not tinghamshire, UK) 750A direct drill.
Moved to section 2.2.
2.3. Earthworms were sampled in the autumn (October) – which year, please explain WHY in this moment
The methodology used (Stroud, 2019) states that optimal sampling is during the autumn or spring due to greater soil moisture content and earthworm activity – this is now stated in section 2.3. The year of sampling is now stated in section 2.3.
2.4. It is mandatory to insert the data into the results of the research on the CN relationship in the soil on the individual three treatments.
Data now included as a graph in Figure 3, also includes soil moisture
Cited, on page 150: Total earthworm counts were highest in the ZTMG treatment, after that on page 189 cited: Soil moisture levels were significantly different between all treatments (Table 2), with the PG being the wettest area, and the ZTMG the driest. I can’t believe???? The number of earthworms is fundamentally dependent on soil moisture, regardless of the method of soil management (conservation or regenerative agriculture). If the soil is drier, earthworms migrate deeper into the soil solum. Can you clarify this? This is crucial point of this paper. By the way, in paper present only one soil sampling in October.
Fair comment. The word ‘driest’ is perhaps misleading as it is actually referring to the soil moisture content just being lower rather than the soil being dry i.e. soil moisture is present in all 3 treatments, higher in the PG treatment but not absent in the ZTMG. This has now been rephrased and makes reference to the newly inserted figure 3 for clarification.
Reviewer 2 Report
The article may not be an outstanding contribution to the field, however, contains original parts, i.e., the study of earthworms in Hertfordshire, UK. It is well- written and well-documented and the conclusions are supported with clarity.
1. Do you consider the topic original or relevant in the field? Does it address a specific gap in the field? and
2. What does it add to the subject area compared with other published material?
To my knowledge, the manuscript investigates the effect of 1) ungrazed permanent grassland, (2) a three year grass-clover ley within an arable zero tillage system without grazing and (3) identical to treatment 2 but with mob-grazing four functional groups: epigeic (surface dwellers), endogeic (sub-surface), anecic (deep soil) and juveniles for the first time in Hertfordshire, UK.
3. What specific improvements should the authors consider regarding the methodology? What further controls should be considered?
For this purpose the authors have employed up-to-date methodology. Their suggestions for future work might be needed.
Author Response
Thank you for the constructive comments. Please find responses below.
For this purpose the authors have employed up-to-date methodology. Their suggestions for future work might be needed.
Discussion Page 10 states 'Future work to evaluate the temporal impact of livestock grazing over multiple years and at different times during the season, its duration and the length of the grass-clover ley recovery period would be of further interest.' This is also reiterated in the conclusions 'This study evaluates a single snapshot in time. A further assessment of how the presence of livestock at different times during the season influences earthworm distribution, coupled with variation in grazing extent and how long the grass-clover ley is given to recover monitored over subsequent years represents important future work.'
Reviewer 3 Report
The research paper by Trickett and Warner aimed to investigate and compare earthworm abundance in three split-plot treatments. In particular: i) ungrazed permanent grassland, ii) a 3-year grass-clover ley within an arable zero tillage system without grazing, and iii) identical to treatment (ii) but with mob-grazing.
Overall, the paper presents a simple and well-conducted experiment. The authors showed great ability in well explaining the main obtained outcomes. Statistics have been conducted in a really serious manner, a correct pre-treatment data; an aspect that is often neglected in almost the research I review for all international journals. Results and their discussion are well-supported without speculative comments. The writing is clear from both stylistic and scientific viewpoints.
Overall, just a few minor revisions are suggested before its publication. In particular:
- lines 105-109: please remember that the Latin name must be always followed by the name of the person that firstly described the species or the last one who changed its name according to botanic nomenclature rules. Be consistent along with the entire paper;
- site description: please add the classification of investigated soil at the Subgroup or Reference + qualifiers level according to Soil Taxonomy (USDA) OR the WRB (FAO) taxonomical system, respectively;
- Table 2: please note that statistical significance should be placed after the number not before (see Asymp. Sig.);
- lines 183-184: rather than "Error bars = one standard error of the mean" it could be better "Error bars = ± standard error of the mean";
- Table 3: see previous comments on Table 2;
- Fig 3: please increase letters' size. They must be clearly visible in a standard published article;
- line 205: rather than versus, could be better to use "vs". Be consistent along with the entire paper;
- Conclusions: please add something about the main limits of your research as well as the possible future perspectives.
Author Response
Thank you for the constructive comments, please find responses below.
lines 105-109: please remember that the Latin name must be always followed by the name of the person that firstly described the species or the last one who changed its name according to botanic nomenclature rules. Be consistent along with the entire paper;
amended
site description: please add the classification of investigated soil at the Subgroup or Reference + qualifiers level according to Soil Taxonomy (USDA) OR the WRB (FAO) taxonomical system, respectively;
added pages 2 and 3
Table 2: please note that statistical significance should be placed after the number not before (see Asymp. Sig.);
amended
lines 183-184: rather than "Error bars = one standard error of the mean" it could be better "Error bars = ± standard error of the mean";
amended
Table 3: see previous comments on Table 2;
amended
Fig 3: please increase letters' size. They must be clearly visible in a standard published article;
amended
line 205: rather than versus, could be better to use "vs". Be consistent along with the entire paper;
amended
Conclusions: please add something about the main limits of your research as well as the possible future perspectives.
added 'This study evaluates a single snapshot in time. A further assessment of how the presence of livestock at different times during the season influences earthworm distribution, coupled with variation in grazing extent and how long the grass-clover ley is given to recover monitored over subsequent years represents important future work.'
Round 2
Reviewer 1 Report
Row 91. The type of soil is written with a capital letter (Stagnic Luvisol). Please explain what the abbreviation LVj means? Insert a reference to the soil type: IUSS Working Group WRB. 2015. World Reference Base for Soil Resources 2014, update 2015. International soil classification system for naming soils and creating legends for soil maps. World Soil Resources Reports No. 106. FAO, Rome.
Row 139. The authors did not honor my last request. 2.4. It is mandatory to insert the data into the results of the research on the CN relationship in the soil on the individual three treatments
Author Response
Thank you for the comments.
Row 91. The type of soil is written with a capital letter (Stagnic Luvisol).
amended
Please explain what the abbreviation LVj means?
Abbreviation for Stagnic Luvisol according to Harmonized World Soil Database (2009) version 1.1, has been removed as probably not necessary
Insert a reference to the soil type: IUSS Working Group WRB. 2015. World Reference Base for Soil Resources 2014, update 2015. International soil classification system for naming soils and creating legends for soil maps. World Soil Resources Reports No. 106. FAO, Rome.
added
Row 139. The authors did not honor my last request. 2.4. It is mandatory to insert the data into the results of the research on the CN relationship in the soil on the individual three treatments
I'm sorry but i'm not quite sure what you are referring to here. The soil analysis was of moisture content and organic matter content as stated in section 2.4 and now shown in Figure 3. The carbon content of SOM is now stated in section 2.4 in reference to the method of Santisteban et al., 2004. Nitrogen was not measured. The discussion references publications that have measured the C:N ratios in plant foliage of different vegetation types e.g. ryegrass and clover, these are now stated in greater detail in the discussion on line 286.
