Croplands Quality Evaluation of Whole Tillage Layer Based on the Minimum Data Set in Jilin Province, China

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Comments:

1.     The authors should expand the literature review section to include a more thorough analysis of previous research on soil quality indicators, particularly focusing on similar temperate regions or black soil areas to help situate their findings within the existing body of knowledge. An in-depth review might also reveal gaps in the current research that this study could address more clearly.

2.     Although the article mentions 12 physicochemical soil indexes, an explicit rationale for the selection of each indicator in the Minimum Data Set (MDS) could be provided to strengthen the methodology by detailing how specific indicators relate to soil health and crop yield, thus justifying their inclusion based on scientific literature and field observations.

3.     While the study predominantly examines physicochemical indicators, the inclusion of biological indicators—such as microbial activity or soil organic carbon levels—could provide a more holistic assessment of soil health. Biological indicators often provide early warnings of soil degradation and can significantly impact crop productivity.

4.     The authors employed principal component analysis (PCA) and correlation analysis to establish the MDS. Providing additional statistical analyses, such as factor analysis or multivariate regression, could further validate the selected soil quality indicators. Sensitivity analysis could also be incorporated to assess which indicators most significantly affect soil quality outcomes.

5.     The study acknowledges regional differences in soil quality, but it could enhance the mapping and analysis of spatial variability. Utilizing advanced geostatistical tools (like kriging) could create more accurate spatial representations of soil quality across regions to help in understanding the influence of landscape features on soil properties, which is crucial for targeted sustainable management practices.

6.     Implementing a longitudinal study design to monitor changes in soil quality over time would provide invaluable data on the effects of different agricultural practices. Such data could help assess the effectiveness of recommended practices and provide a robust basis for policy recommendations.

7.     The article could benefit from discussing how enhancing soil quality through sustainable practices impacts broader ecosystem services, such as water regulation, biodiversity conservation, and climate mitigation. It could be valuable to incorporate ecosystem service valuation as a metric for assessing the benefits of improved soil management in the studied areas.

8.     While the study proposes optimal ranges for soil indicators to support effective farming, it would be prudent to deepen the discussion of policy implications. Highlighting the importance of local and national agricultural policies that promote sustainable practices—coupled with recommended actions for farmers—can help translate research findings into practical guidelines for improving soil quality.

9.     The authors should propose future research directions that could address knowledge gaps identified in the study. This could include the exploration of the socio-economic factors influencing soil management practices or the impact of climate change on soil properties and crop yields.

Comments on the Quality of English Language

need revision

Author Response

Please see the attachment.

Response to the Comments of the manuscript No. agronomy-3299175

We appreciated the editor’s and the reviewers’ comments and suggestions concerning our manuscript. Those comments are all valuable and very helpful for revising and improving our paper, as well as the important guiding significance to our researches. We have studied comments carefully and have made correction which we hope meet with approval. We would be glad to respond to any further questions and comments that you may have. Revised portion are marked using the program of “track changes”. The main corrections in the paper and the responds to the reviewers’ comments are as following:

 

Response to the comments made by the Reviewer #1

 

1. The authors should expand the literature review section to include a more thorough analysis of previous research on soil quality indicators, particularly focusing on similar temperate regions or black soil areas to help situate their findings within the existing body of knowledge. An in-depth review might also reveal gaps in the current research that this study could address more clearly.

Response:Thank you for pointing this out.

 Previous studies on soil quality indicators have focused on model comparison and indicator screening, exploring the response of field management practices, climate, and topographic differences to soil quality in specific regions based on experimental treatment conditions. In contrast, there is a relative paucity of research on the diagnosis and prediction of soil quality indicator scores. In view of this, we screened key indicators and performed threshold determination while conducting soil quality assessment.

Out of the 17 Sustainable Development Goals set by the United Nations, 13 goals are directly or indirectly related to soil [11]. Understanding the current status of soil health, conducting systematic diagnosis and establishing a forecasting system is the basis for safeguarding soil health and an important component of sustainable soil management [12].

Accurate assessment of standardization function scoring thresholds is critical for SQI assessment using scoring functions. Unfortunately, the determination of indicator thresholds is difficult for specific study areas, especially for sub-tillage soils. In most cases, critical values are based on published results that are directly generalized to similar large soil areas [18,19], and existing models perform differently in different regions; in comparison, the better models are mostly site-specific. Given the complexity of soil health to critical values, the best approach is to establish these key soil indicator values based on local soil health objectives [20,21]. (Page 2, Lines 83-87; Page 3, Lines 104-112)

 

Reference

18. Manna, M.C.; Swarup, A.; Wanjari, R.H.; Ravankar, H.N.; Mishra, B.; Saha, M.N. Long term effect of fertilizer and manure application on soil organic carbon storage, soil quality and yield sustainability under subhumid and semi-arid tropical India. Field Crop Res. 2005, 93, 264-
19. Bhaduri, D.; Purakayastha, T.J. Long-term tillage, water and nutrient management in rice-wheat cropping system: assessment and response of soil quality. Soil Tillage 2014, 144, 83-95.
20. Rahmanipour, F.; Marzaioli, R.; Bahrami, H.A.; Fereidouni, Z.; Bandarabadi, S.R. Assessment of soil quality indices in agricultural lands of Qazvin Province. Ecol. Indicat. 2014, 40, 19-26.
21. Guo, L.; Sun, Z.; Ouyang, Z.; Han, D.; Li, F. A comparison of soil quality evaluation methods for Fluvisol along the lower Yellow River. Catena 2017, 152, 135-

 

2. Although the article mentions 12 physicochemical soil indexes, an explicit rationale for the selection of each indicator in the Minimum Data Set (MDS) could be provided to strengthen the methodology by detailing how specific indicators relate to soil health and crop yield, thus justifying their inclusion based on scientific literature and field observations.

Response: SOM was a key indicator of soil health [41], and the increase of soil SOM, AP, TK and AK contents had a positive effect on crop yield [42]. Whereas Sand influences soil moisture content and limits soil nutrient transport, soil pH explains more than 50% of the variation in soil multifunctionality and influences the adsorption and desorption of soil nutrient elements (especially phosphorus), and appropriate Sand and pH indirectly contribute to crop yield and soil health [43,44]. It showed that both TDS and MDS evaluation index systems were well represented in this study. The significant correlation between TDS and MDS soil quality index (SQI) further indicated that MDS could be a better alternative to the TDS indicators for evaluating the SQI of the whole tillage layer in Jilin Province. (Page 17, Lines 456-465)

 

Reference

41. Mahmood, S.; Nunes, M.R.; Kane, D.A.; Lin, Y. Soil health explains the yield-stabilizing effects of soil organic matter under drought. Soil Environ. Health 2023, 1, 100048.
42. Li, S.J.; Chen, X.X.; Wang, Z.K.; Wu, D.X.; Wang, M.; Mueller, T.; Zou, C.Q.; Chen, X.P.; Zhang, W. Phosphorus fertilizer management for high yields in intensive winter wheat-summer maize rotation system: Integrating phosphorus budget and soil available phosphorus. Field Crop Res. 2024, 313, 109410.
43. Suliman, M.; Scaini, A.; Manzoni, S.; Vico, G. Soil properties modulate actual evapotranspiration and precipitation impacts on crop yields in the USA. Sci. Total Environ. 2024, 949, 175172.
44. Cui, J.; Zhou, F.W.; Li, J.F.; Shen, Z.Y.; Zhou, J.; Yang, J.; Jia, Z.J.; Zhang, Z.; Du, F.F.; Yao, D.R. Amendment-driven soil health restoration through soil pH and microbial robustness in a Cd/Cu-combined acidic soil: A ten-year in-situ field experiment. J. Hazard. Mater. 2024, 465, 133109.

 

3. While the study predominantly examines physicochemical indicators, the inclusion of biological indicators—such as microbial activity or soil organic carbon levels—could provide a more holistic assessment of soil health. Biological indicators often provide early warnings of soil degradation and can significantly impact crop productivity.

Response: In this study, organic matter content was converted from organic carbon content, organic matter indicators were filtered into the minimum data set, and the results of the study confirmed the direct impact of soil organic carbon on soil health status. In addition, we added the shortcomings of this study in the discussion, and in view of the impact of microbial activities and bioindicators on soil health, we will follow up with in-depth research on soil microbial diversity and abundance to add to the soil quality assessment indicators. (Page 18, Lines 529-533)

 

4. The authors employed principal component analysis (PCA) and correlation analysis to establish the MDS. Providing additional statistical analyses, such as factor analysis or multivariate regression, could further validate the selected soil quality indicators. Sensitivity analysis could also be incorporated to assess which indicators most significantly affect soil quality outcomes.

Response: To further verify the magnitude of influence of the selected indicators on soil quality, the multiple regression analysis of MDS indicators and soil quality determined the standardized coefficients, which were SOM (0.58) > TK (0.53) > AP (0.33) > Sand (0.31) in top-tillage soils, and Sand (0.73) > pH (0.49) > AK (0.23) > TN (0.16) in sub-tillage soils. Top-tillage soil quality was mainly influenced by SOM and TK, while sub-tillage soil was mainly influenced by Sand and pH. (Page 14, Lines 376-380)

 

5. The study acknowledges regional differences in soil quality, but it could enhance the mapping and analysis of spatial variability. Utilizing advanced geostatistical tools (like kriging) could create more accurate spatial representations of soil quality across regions to help in understanding the influence of landscape features on soil properties, which is crucial for targeted sustainable management practices.

Response: We modified Figure 1 to an elevation map so as to reflect the differences in geomorphic features, with the western part of Jilin Province dominated by plains, the central part by transition zones, and the eastern part by higher elevations. Regional differences were also identified using one-way ANOVA in conjunction with Figure 2, Figure 3, Table 5 and Table 8.

 

6. Implementing a longitudinal study design to monitor changes in soil quality over time would provide invaluable data on the effects of different agricultural practices. Such data could help assess the effectiveness of recommended practices and provide a robust basis for policy recommendations.

Response: We agree with this comment. The longitudinal study design spanned a large time period due to the large regional sampling area and the difficulty of continuous monitoring. We explore the differences between this study and the Second National Soil Census (1979-1984), 2005-2010 and 2018 data in our discussion. We also plan to conduct the next soil sample collection in five years to supplement soil bioindicators and provide a basis for policy recommendations.

 

7. The article could benefit from discussing how enhancing soil quality through sustainable practices impacts broader ecosystem services, such as water regulation, biodiversity conservation, and climate mitigation. It could be valuable to incorporate ecosystem service valuation as a metric for assessing the benefits of improved soil management in the studied areas.

Response: We agree with this comment. This study analyzes the regional soil status with the objective of soil quality index. Ecosystem services, as an emerging field of research, are closely related to the sustainable development of the region. Most studies have emphasized the importance of areas with high levels of ecosystem services for the whole region. However some sites with special contribution to regional ecosystem services are still neglected. Utilizing the InVEST model to assess the unique contribution of ecosystem services supplying biodiversity and to the region in combination with water regulation and climate regulation will be our future research direction.

 

8. While the study proposes optimal ranges for soil indicators to support effective farming, it would be prudent to deepen the discussion of policy implications. Highlighting the importance of local and national agricultural policies that promote sustainable practices—coupled with recommended actions for farmers—can help translate research findings into practical guidelines for improving soil quality.

Response: Most of the soil conditions in the study area did not reach the threshold range, and there is a long way to go to improve soil quality. The dominant endogenous cause of black soil degradation is emphasized in the black soil conservation policy issued in China as a decrease in organic matter[3,4]. Anthropogenic soil management (organic matter returned with tillage practices) plays a vital role in increasing soil organic carbon and available nutrient content [48], and a large amount of organic matter resources (straw, manure) in the Northeast offers the possibility of improving the top-tillage soil quality [49]. Fertilizer use of straw realizes straw resource management, optimizes soil structure, and regulates soil pH, while straw returned to the field brings in a variety of elements, and the stimulating effect of exogenous carbon makes a great contribution to nutrient activation. Conservation tillage (no-tillage with straw mulching) measures were applied in the western region of Jilin Province to protect the black soil by reducing wind erosion, improving soil fertility, increasing crop yields, and lowering operating costs [5]. The deep soil structure and pH in the central and eastern regions limit the sub-tillage soil quality. Straw deep ploughing can improve the nutrient content of the sub-tillage soil and alleviate the soil acidification problem [24]. Compared with traditional rotary tillage, increasing the tillage depth can break the plow subsoil layer, increase water storage and water supply capacity, and create a better-growing environment for the crop root system [50], improving crop yields. (Page 18, Lines 504-523)

 

Reference

3. Li, X.Y.; Wang, D.Y.; Ren, Y.X.; Wang, Z.M.; Zhou, Y.H. Soil quality assessment of croplands in the black soil zone of Jilin Province, China: Establishing a minimum data set model. Ecol. Indic. 2019, 107, 105251.
4. Li, R.; Hu, W.Y.; Jia, Z.J.; Liu, H.Q.; Zhang, C.; Huang, B.; Yang, S.H.; Zhao, Y.G.; Zhao, Y.C.; Shukla, M.K.; Taboada, M.A. Soil degradation: a global threat to sustainable use of black soil. Pedosphere 2024.
5. Zhao, L.P.; Wang, H.B.; Liu, H.Q.; Wang, Y.L.; Liu, S.X.; Wang, Y. Mechanism of fertility degradation of black soil in corn belt of Songliao plain. Acta Pedologica Sinica 2006, 43, 78-84.
6. Zou, W.X.; Han, X.Z.; Lu, X.C.; Chen, X.; Yan, J.; Song, B.H.; Yang, N.; Lin, Q.H.; He, Y. Effects of the construction of fertile and cultivated upland soil layer on soil fertility and maize yield in black soil region in Northeast China. Chinese Journal of Applied Ecology 2020, 31, 4134-4146.
7. Zhang, N.W.; Chen, X.; Wang, J.; Dong, H.; Han, X.; Lu, X.; Yan, J.; Zou, W. Anthropogenic soil management performs an important role in increasing soil organic carbon content in northeastern China: A meta-analysis. Agr. Ecosyst. Environ. 2023, 350, 108481.
8. Feng, H.L.; Han, X.Z.; Zhu, Y.C.; Zhang, M.; Ji, Y.X.; Lu, X.C.; Chen, X.; Yan, J.; Zou, W.X. Effects of long-term application of organic materials on soil water extractable organic matter, fulvic acid, humic acid structure and microbial driving mechanisms. Plant Soil 2024, 501, 323-341.
9. Getahun, G.T.; Ktterer, T.; Munkholm, L.J.; Parvage, M.M.; Keller, T.; Rychel, K.; Kirchmann, H. Short-term effects of loosening and incorporation of straw slurry into the upper subsoil on soil physical properties and crop yield. Soil Till. Res. 2018, 184, 62-67.

 

9. The authors should propose future research directions that could address knowledge gaps identified in the study. This could include the exploration of the socio-economic factors influencing soil management practices or the impact of climate change on soil properties and crop yields.

Response: In this study, data from 185 sites were collected and 12 physical and chemical indicators were utilized to assess the soil quality status in Jilin Province. Soil biological indicators, crop yields, seasonal or climatic changes, and socio-economic factors were not taken into account, so it is necessary to further refine and optimize the evaluation system in future extensive research, and future extension to the practice of implementing sustainable development in the black soil. (Page 18, Lines 528-533)

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Dear Editor-in-Chief,

Thank you for giving me the opportunity to review the manuscript entitled “Croplands quality evaluation of whole tillage layer based on the minimum data set in Jilin Province, China “

 

The study aims to assess cropland quality in Jilin Province, China, through soil quality evaluations across top- and sub-tillage layers, with particular attention to the spatial distribution of physicochemical properties and the selection of minimum data set (MDS) indicators. This research is innovative as it addresses the underexplored sub-tillage layer within the black soil zone, thus providing a more holistic view of soil quality management. Additionally, the study uses GIS and PCA to develop a novel soil quality index (SQI), which is creative compared to prior research focused primarily on top-tillage layers. The data collected is original and comprehensive.

1- The introduction is adequately detailed, clearly presenting the study’s rationale, previous findings on black soil, and specific objectives. It is coherent and aligns with the research goals, though it may be condensed slightly by removing overlapping details regarding black soil challenges (p.3, line 51-62).

2- Accuracy of experiment description: While most steps are detailed, the calculation formulas for SQI could be expanded for reproducibility.

3- The study appropriately measures variables for confirming the objectives. However, additional context on soil moisture or microbial activity could improve interpretations related to soil quality.

4- Results are detailed and appropriately organized, but some tables, such as soil physicochemical properties (p. 8, Table 2), could benefit from clearer formatting or legends to improve readability. The spatial distribution graphs are informative, though additional labels on Figures 2 and 3 for distinct ecological zones would help clarify regional differences.

5- The discussion covers the significance of findings comprehensively, addressing mechanisms for varying soil responses across ecological zones. However, it lacks depth in exploring specific biochemical mechanisms, such as nutrient cycling or microbial influences, which would strengthen the analysis (p. 16-17).

6- The conclusion effectively summarizes the study's implications and the importance of regional SQI variation for tillage layer management. However, limitations related to seasonal variations or climate impact on soil properties could be acknowledged, and future research could expand on implementing sustainable soil quality practices.

7- References are recent and relevant, though a few older sources could be updated with newer studies in soil quality assessment to enhance the bibliography.

8- The manuscript generally uses correct scientific English, though it contains minor grammatical errors and complex sentence structures that can be simplified for clarity. Instances include:

• Page 3, line 53: Replace "suitable for farming and production potential" with "suitable for farming with high production potential."
• Page 17, line 401: Simplify "increasing trend from west to east among regions, which is basically in line with…" to "increase from west to east, aligning with…"

 

 

Author Response

Please see the attachment.

Response to the Comments of the manuscript No. agronomy-3299175

We appreciated the editor’s and the reviewers’ comments and suggestions concerning our manuscript. Those comments are all valuable and very helpful for revising and improving our paper, as well as the important guiding significance to our researches. We have studied comments carefully and have made correction which we hope meet with approval. We would be glad to respond to any further questions and comments that you may have. Revised portion are marked using the program of “track changes”. The main corrections in the paper and the responds to the reviewers’ comments are as following:

 

Response to the comments made by the Reviewer #2

 

1. The introduction is adequately detailed, clearly presenting the study’s rationale, previous findings on black soil, and specific objectives. It is coherent and aligns with the research goals, though it may be condensed slightly by removing overlapping details regarding black soil challenges (p.3, line 51-62).

Response: Thank you for pointing this out. It has been revised.

 

2. Accuracy of experiment description: While most steps are detailed, the calculation formulas for SQI could be expanded for reproducibility.

Response: The formula for calculating the SQI in the manuscript refers to a large literature and is consistent with previous research methods, and we further supplemented the data sources for the weights.

 

3. The study appropriately measures variables for confirming the objectives. However, additional context on soil moisture or microbial activity could improve interpretations related to soil quality.

Response: In this study, organic matter indicators were filtered into the minimum dataset, and the results of the study confirmed the direct impact of soil organic carbon on soil health status. In addition, we added the shortcomings of this study in the discussion, and in view of the impact of microbial activities and bioindicators on soil health, we will follow up with in-depth research on soil microbial diversity and abundance to add to the soil quality assessment indicators.

 

4. Results are detailed and appropriately organized, but some tables, such as soil physicochemical properties (p. 8, Table 2), could benefit from clearer formatting or legends to improve readability. The spatial distribution graphs are informative, though additional labels on Figures 2 and 3 for distinct ecological zones would help clarify regional differences.

Response: We have updated the legends and labeling of the full text figures and tables.

 

5. The discussion covers the significance of findings comprehensively, addressing mechanisms for varying soil responses across ecological zones. However, it lacks depth in exploring specific biochemical mechanisms, such as nutrient cycling or microbial influences, which would strengthen the analysis (p. 16-17).

Response: SOM was a key indicator of soil health [41], organic carbon promotes higher microbial volume and activity, and microbial-mediated pathways, as the core of soil nutrient cycling, further improve soil nitrogen and phosphorus availability through the regulation of key enzyme activities and carbon, nitrogen, and phosphorus stoichiometric ratios [42]. Increased soil SOM, AP, TK and AK content positively affects crop yield [43]. Whereas Sand influences soil moisture content and limits soil nutrient transport, soil pH explains more than 50% of the variation in soil multifunctionality and influences the adsorption and desorption of soil nutrient elements (especially phosphorus), and appropriate Sand and pH indirectly contribute to crop yield and soil health [44,45]. (Page 17, Lines 456-465)

 

Reference

41. Mahmood, S.; Nunes, M.R.; Kane, D.A.; Lin, Y. Soil health explains the yield-stabilizing effects of soil organic matter under drought. Soil Environ. Health 2023, 1, 100048.
42. Luo, G.W.; Sun, B.; Li, L.; Li, M.H.; Liu, M.Q.; Zhu, Y.Y.; Guo, S.W.; Ling, N.; Shen, Q.R. Understanding how long-term organic amendments increase soil phosphorus activities: Insight into phoD- and phoC-harboring functional microbial populations. Soil Biol. Biochem. 2019, 139, 107632.
43. Li, S.J.; Chen, X.X.; Wang, Z.K.; Wu, D.X.; Wang, M.; Mueller, T.; Zou, C.Q.; Chen, X.P.; Zhang, W. Phosphorus fertilizer management for high yields in intensive winter wheat-summer maize rotation system: Integrating phosphorus budget and soil available phosphorus. Field Crop Res. 2024, 313, 109410.
44. Suliman, M.; Scaini, A.; Manzoni, S.; Vico, G. Soil properties modulate actual evapotranspiration and precipitation impacts on crop yields in the USA. Sci. Total Environ. 2024, 949, 175172.
45. Cui, J.; Zhou, F.W.; Li, J.F.; Shen, Z.Y.; Zhou, J.; Yang, J.; Jia, Z.J.; Zhang, Z.; Du, F.F.; Yao, D.R. Amendment-driven soil health restoration through soil pH and microbial robustness in a Cd/Cu-combined acidic soil: A ten-year in-situ field experiment. J. Hazard. Mater. 2024, 465, 133109.

 

6. The conclusion effectively summarizes the study's implications and the importance of regional SQI variation for tillage layer management. However, limitations related to seasonal variations or climate impact on soil properties could be acknowledged, and future research could expand on implementing sustainable soil quality practices.

Response: In this study, data from 185 sites were collected and 12 physical and chemical indicators were utilized to assess the soil quality status in Jilin Province. Soil biological indicators, crop yields, seasonal or climatic changes, and socio-economic factors were not taken into account, so it is necessary to further refine and optimize the evaluation system in future extensive research, and future extension to the practice of implementing sustainable development in the black soil. (Page 18, Lines 529-533)

 

7. References are recent and relevant, though a few older sources could be updated with newer studies in soil quality assessment to enhance the bibliography.

Response: It has been revised.

 

8. The manuscript generally uses correct scientific English, though it contains minor grammatical errors and complex sentence structures that can be simplified for clarity. Instances include: Page 3, line 53: Replace "suitable for farming and production potential" with "suitable for farming with high production potential." Page 17, line 401: Simplify "increasing trend from west to east among regions, which is basically in line with…" to "increase from west to east, aligning with…"

Response: It has been revised.

 

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

There is a large element of mathematics in the paper, but the usefulness is low. There needs to be a complementary description of methodology. Information that traditional methods are not enough. The text of the paper is not very readable. Sentences very long and containing too much information. Conclusions are general. So worded does not give practical guidance. Targeted action is too little information. 23 specific comments are highlighted in the text.

Comments for author File: Comments.pdf

Author Response

Please see the attachment.

Response to the Comments of the manuscript No. agronomy-3299175

We appreciated the editor’s and the reviewers’ comments and suggestions concerning our manuscript. Those comments are all valuable and very helpful for revising and improving our paper, as well as the important guiding significance to our researches. We have studied comments carefully and have made correction which we hope meet with approval. We would be glad to respond to any further questions and comments that you may have. Revised portion are marked using the program of “track changes”. The main corrections in the paper and the responds to the reviewers’ comments are as following:

 

Response to the comments made by the Reviewer #3

 

There is a large element of mathematics in the paper, but the usefulness is low. There needs to be a complementary description of methodology. Information that traditional methods are not enough. The text of the paper is not very readable. Sentences very long and containing too much information. Conclusions are general. So worded does not give practical guidance. Targeted action is too little information. 23 specific comments are highlighted in the text.

 

1. E-mail addresses of the authors are missing.

Response: Thank you for pointing this out. It has been added.

 

2. According to the magazine's editorial policy. The abstract should not exceed 200 words. Instructions to authors should be read.

Response: The abstract word count has been reduced.

 

3. What grades does this apply to?

Response: The grade is based on the 2019 National Cultivated Land Quality Grade Status Bulletin issued by China's Ministry of Agriculture and Rural Development (MARD), which applies to the vague assessment of farmland soil quality. It has been supplemented in the manuscript. (Page 2, Line 63)

 

4. Clarify what is meant by the abbreviations SQI and MDS.

Response: Soil quality index (SQI) is a comprehensive indicator for evaluating soil quality, taking into accout the physical, chemical, and biological characteristics of the soil. It comprehensively reflects the soil condition, accurately evaluating cropland's whole tillage soil quality and improving its obstacles are highly relevant to rational tillage construction and sustainable agricultural development. Minimum data set (MDS) method is to optimize and simplify large amounts of date by using principal component and correlation analysis, and to comprehensively characterize a research object by collecting the least amount of data. The meaning of SQI and MDS has been described in the manuscript. (Page 2, Lines 87-88; Page 3, Lines 95-98)

 

5. Why only potassium?

Response: Soil quality evaluation studies in the Northeast black soil zone have mostly screened indicators such as bulk density, pH, cation exchange capacity, organic matter, and total potassium into the MDS. It has been revised. (Page 3, Lines 114-115)

 

6. Clarify what is meant by the abbreviations GIS.

Response: GIS stands for Global Positioning Systems and has been added to the manuscript. (Page 3, Line 123)

 

7. No d only days

Response: It has been revised. (Page 3, Line 134)

 

8. In the European Union there are relevant standards for soil sampling and analysis. Authors submitting articles to this journal should be familiar with them and apply them.

Response: It has been revised. Five soil cores (5 cm diameter covering 0-40 cm depth) were randomly collected from each plot and divided into two parts (0-20 cm and 20-40 cm), and then mixed independently to make two composite samples. The soil cores were gently broken apart along the natural break points and sieved (< 5 mm) to remove visible plant matter and organic debris [26]. The samples were air-dried, ground, and stored for backup. (Page 4, Line 145-150)

 

References

26. Jerray, A.; Rumpel, C.; Roux, X.L.; Massad, R.S.; Chabbi, A. N2O emissions from cropland and grassland management systems are determined by soil organic matter quality and soil physical parameters rather than carbon stock and denitrifier abundances. Soil Biol. Biochem. 2024, 190, 109274.

 

9. What traditional methods mean? It is just a phrase.

Response: The standard methods were used to measure soil samples. It has been revised.

 

10. In which solution was the pH determined?

Response: The soil pH was determined using a 1:2.5 soil-water suspension. It has been revised. (Page 4, Line 158)

 

11. There is a lack of information on what solutions were used to extract the soil.

Response: The standard methods were used to measure soil samples [18]: soil pH was determined using a 1:2.5 soil-water suspension, CEC was estimated using the ammonium acetate saturation method, SOM by potassium dichromate volumetric method-external heating method, TN by semi-micro-volume Kjeldahl method, TP by sodium hydroxide melt-molybdenum antimony antimony colorimetric method, TK by sodium hydroxide melting-flame photometric method, AN by alkaline diffusion method, AP by 0.5 mol L^-1 NaHCO₃ extraction-molybdenum antimony colorimetric method, AK by 1 mol L^-1 NH₄OAc leaching-flame photometric method, and soil mechanical composition was determined by gravimetric method. (Page 4, Lines 157-166)

 

12. The units are written incorrectly. The letter g must be followed by the symbol of the element being denoted.

Response: This has been modified for ease of reading. (Page 6, Lines 222-225; Page 9, Lines 268-271)

 

13. All data from the supplement must be included in the text of the article.

Response: It has been revised.

 

14. What is this strange sentence?

Response: It has been revised.

 

15. All data from the supplement must be included in the text of the article.

Response: It has been revised.

 

16. All data from the supplement must be included in the text of the article.

Response: It has been revised.

 

17. ?

Response: It has been revised.

 

18. All abbreviations must be explained below the table.

Response: It has been revised.

 

19. On what basis is this written?

Response: This section is based on data from the Second National Soil Survey (1979-1984, China). Soil quality changes were compared longitudinally through time differences. In contrast, soil acidification increased after 40 years of continuous cultivation and fertilization measures.

 

20. There is no information on what methods were used to determine soil richness in the compared articles. So it is difficult to compare.

Response: Among the indicators in the different regions, one-way ANOVA (P<0.05) was used to clarify the differences between the indicators in the Eastern, Central and Western parts of the country, while Arcgis two-dimensional maps were used to visualize the data.

 

21. These are not 12 physico-chemical indicators. There are also chemical indicators.

Response: It has been revised.

 

22. Conclusions not very concrete. They do not provide practical guidance. Guided action, but what direction.

Response: It has been revised.

 

23. References should be edited according to the editor's requirements. Authors should read the instructions on the journal's website.

Response: It has been checked and modified

 

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Agree

Author Response

We appreciated the reviewers’ comments and suggestions concerning our manuscript. We have further optimized the manuscript content.

Reviewer 2 Report

Comments and Suggestions for Authors

No more comments

Author Response

We appreciated the reviewers’ comments and suggestions concerning our manuscript. We have further optimized the manuscript content.

Reviewer 3 Report

Comments and Suggestions for Authors

Most of the comments were taken into account by the authors. Individual comments remain and are highlighted in the text. The paper still contains a large element of mathematics, but its usefulness is low. The methodology has been improved. The text of the paper is not very readable. Sentences still very long and containing too much information. Conclusions are improved. Practical tips have been given.

Comments for author File: Comments.pdf

Comments on the Quality of English Language

Most of the comments were taken into account by the authors. Individual comments remain and are highlighted in the text. The paper still contains a large element of mathematics, but its usefulness is low. The methodology has been improved. The text of the paper is not very readable. Sentences still very long and containing too much information. Conclusions are improved. Practical tips have been given.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf