Changes in Organic Carbon in Mineral Topsoil of a Formerly Cultivated Arenosol under Different Land Uses in Lithuania

Answers to 1. reviewer's comments

Line No.

Reviewer's comment

Answers to reviewer's comments

1.    Revise the introduction section incorporating progressive and retrogressive land use changes and its impact on the environment

2.    Incorporate more on the sources that enhances recalcitrant carbon pool in soil.

The introduction has been rewritten and we added some new sentences (after L34):

Corg accumulation and distribution in the soil profile is associated not only with the root architecture of plants [12] but also with the leaching of organic compounds into the deeper soil layers under the leaching moisture regime [13,14]. Depending on the soil, climatic conditions, agrotechnical measures, leaching of Corg may vary from 8-10 kg ha^-1 year^-1 [15] till 170-310 kg ha^-1 year^-1 [16].

It has been added some new references:

12.  Nielsen, K.L., Lynch, J.P., Jablokow, A.G., Curtis P.S. Carbon cost of root systems: an architectural approach. Plant Soil 1994, 165, 161–169. https://doi.org/10.1007/BF00009972

13.  Watkins, M.D., Hulugalle, N.R., Weaver, T.B., Finlay, L.A., McCorkell B.E. Leaching of dissolved organic carbon and nitrogen under cotton farming systems in a Vertisol. Soil Use and Management 2019, 35(3), 443–452. https://doi.org/10.1111/sum.12510

14.  Lepistö, A., Kortelainen, P., Mattsson, T. Increased organic C and N leaching in a northern boreal river basin in Finland. Global Biogeochemical Cycles 2008, 22(3), https://doi.org/10.1029/2007GB003175

15. Tripolskaja, L., Booth, C. A., Fullen, M. A. A lysimeter study of organic carbon leaching from green manure and straw into a sandy loam Haplic Luvisol. Zemdirbyste-Agriculture, 2013, 100 (1), 3–8.

16.  Vinther, F.P., Hansen, E.M., Eriksen, J. Leaching of soil organic carbon and nitrogen in sandy soils after cultivating grass-clover swards. Biol Fertil Soils 2006, 43, 12–19. https://doi.org/10.1007/s00374-005-0055-4

Also, we added:

Corg stocks in arable soils can be increased by applying various types of organic fertilizers (manure, biochar, green manure) or minimizing tillage [17-19]. By transforming arable land use into other, different effects of change in Corg stocks are possible.

17.    Arlauskienė, A., Šarūnaitė, L. Kadžiūlienė, Ž. Agronomic practice and performance of organic farms in different environmental conditions in Lithuania. Biological Agriculture & Horticulture 2021, 37(2), 91–106. https://doi.org/10.1080/01448765.2020.1850351

18.    Šrank, D., Šimansky, V. Differences in soil organic matter and humus of sandy soil after application of biochar substrates and combination of biochar substrates with mineral fertilizers. Acta fytotechn zootechn 2020, 23, 2020(3), 117–124. https://doi.org/10.15414/afz.2020.23.03.117-124

19.    Feiziene, D., Feiza, V., Karklins, A., Versulienė, A., Janusauskaite, D., Antanaitis, S. 2018. After-effects of long-term tillage and residue management on topsoil state in Boreal conditions. European Journal of Agronomy 2018, 94, 12–24.

Another sentence has been added:

Whereas decrease in Corg stocks is seen in the transformation of forest land use to pasture, which is associated with lower organic matter deposition in the soil [25].

25.Dalal, R.C., Thornton, C.M., Allen, E., Owens, J.S., Kopittke, P.M. Long-term land use change in Australia from native forest decreases all fractions of soil organic carbon, including resistant organic carbon, for cropping but not sown pasture. Agriculture, Ecosystems & Environment 2021,  311, 107326. https://doi.org/10.1016/j.agee.2021.107326

According to new literature sources the references numbering has been changed.

L 80

3.     Incorporate appropriate citation in LN 80 after “The soil was formed on fluvioglacial deposits and has the following profile: Ap-AB-B1-B2-1C-C2”

It has been added the sentence:

These hydrothermal conditions are conducive to the precipitation filtration and leaching of biogenic elements from upper soil layers.

The citation is according: Tripolskaja L., Impact of climate variability on precipitation filtration in Lithuania; In. Book of abstract. 20^th Baltic agronomy forum, Jelgava, 2016, p. 47

However, we would like to point out that in order to avoid self-citation, efforts are made to exclude literature sources on behalf of Tripolskaya.

We added the citation after the sentence “The soil was formed on fluvioglacial deposits and has the following profile: Ap-AB-B1-B2-1C-C2”. The reference is: FAO. International Soil Classification System for Naming Soils and Creating Legends for Soil Maps; WRB 2014, Update 2015; World Reference base for soil Resourses 2014, Update 2015; Food and Agriculture organization of the United Nations: Rome, Italy, 2015; p.192.

The reference number has been changed.

L 123

4.    Include the soil texture class in LN 123.

It has been added the soil texture class and in the L 123 it has been written: The amount of clay particles in the AB horizon changed marginally compared to the A horizon. According to texture and diagnostics horizon propeties the soil belongs to coarse sand Arenosol.

The reference number has been changed.

Tab. 2

5.    Table 2 describes P₂O₅ and K₂O, please provide the methods used for these analysis under the sub-section soil sampling and analysis.

The analysis methods of P₂O₅ and K₂O have been added in the section Materials and Methods: Plant available P2O5 and K2O were extracted using 0.03 M ammonium lactate (EgnerRiehm-Domingo (A–L) method).

Fig. 2

6.    Figure 2, please specify if the values are for R or R². If it for R, please explain why your preferred using R over R².

R² is a measure of how well a linear regression model fits the data. It can be interpreted as the proportion of variance of the outcome Y explained by the linear regression model. It is a number between 0 and 1 (0 ≤ R² ≤ 1). The closer its value is to 1, the more variability the model explains. And R² = 0 means that the model cannot explain any variability in the outcome Y.

On the other hand, the correlation coefficient R is a measure that quantifies the strength of the linear relationship between 2 variables. R is a number between -1 and 1 (-1 ≤ r ≤ 1). A value of r close to -1: means that there is negative correlation between the variables (when one increases the other decreases and vice versa). A value of r close to 0: indicates that the 2 variables are not correlated (no linear relationship exists between them). A value of r close to 1: indicates a positive linear relationship between the 2 variables (when one increases, the other does).

The both R and R² measure the strength of the linear relationship between 2 variables. When we’re dealing with a simple linear regression: Y = β₀ + β₁X + ε R² will be the square of the correlation between the independent variable X and the outcome Y: R² = Cor(X, Y) ²

And in simple linear regression we have 1 independent variable X and 1 dependent variable Y, so calculating the correlation between X and Y is no problem. In multiple linear regression we have more than 1 independent variable X, therefore we cannot calculate r between more than 1 X and Y. When dealing with multiple linear regression: Y = β₀ + β₁X₁ + β₂X₂ + β₃X₃ + β₄X₄ + … + ε

R² will be the square of the correlation between the predicted/fitted values of the linear regression (Ŷ) and the outcome (Y): R² = Cor(Ŷ, Y) ²

Note that in the special case of the simple linear regression:
Cor( X, Ŷ) = 1 So: Cor( X, Y ) = Cor( Ŷ, Y )

Which is why, in that special case:
R² = Cor( Ŷ, Y ) ² = Cor( X, Y ) ²

According to the information above and the correlation in the figure 2 (correlation is between two variables Sand particles (Y) and Corg (X) we can use R. And as it was said above R is a measure that quantifies the strength of the linear relationship between 2 variables. R is a number between -1 and 1 (-1 ≤ r ≤ 1).

Fig. 3

7.    Figure 3, what is the purpose of giving three-dimensional bar. Pls, change it into two dimensions.

It has been changed Figure 3 (now Figure 2): the three-dimension bar has been changed into two-dimension. According to another reviewer remark we refused the Figure 1, so the numbering of figures has been changed. The figure number have changed into Figure 2.

Fig. 4

8.    Figure 4, pls use the values in a tabular for better understanding

In our opinion the Figure 4 (now Figure 3) very clearly visually shows the differences of humic and fulvic acids stocks in A horizon of different land uses. Thank you for the remark, but all authors ask a permission to leave this figure if we have that possibility. According to another reviewer remark we refused the Figure 1, so the numbering of figures has been changed. The figure number have changed into Figure 3.

9.    Discussion part needs a thorough rework. In the present form it does not discusses all the result presented in the manuscript. Pls elaborate it more covering all the objectives presented in the article.

It has been made a mistake and the section Discussion is the Conclusions section. Also, the Results section is Results and discussion section. Thank You for the remark and we are very sorry for the mistake. The names of the sections have been changed (Results into Results and discussion; Discussion into Conclusions).

10.  Add a conclusion section along with the implications of the study.

As we have written above it has been made a mistake and the Discussion section is the Conclusions section. Thank You for the remark and we are very sorry for the mistake. The names of the section have been changed (Discussion into Conclusions).

Answers to 2 reviewer's comments

Line No.

Reviewer's comment

Answers to reviewer's comments

Paper organization: 1) Results section holds much discussion 2) Discussion is no discussion

It has been made a mistake and the section Discussion is the Conclusions section. Also, the Results section is Results and discussion section. Thank You for the remark and we are very sorry for the mistake. The names of the sections have been changed (Results into Results and discussion; Discussion into Conclusions).

L 224-232

Writing: 1) inconsistent or inconsequent, not enough pointed to main statements (e.g. lines 224-232) 2) I am not a native speaker, nevertheless the Englsh sounds bumby, text needs linguistic improvement.

23 years after the conversion of land use from CL to MG, AL and PP, Corg concentration in the soil changed depending on the vegetation cover and plant cultivation agrotechniques. In 2018, a higher Corg concentration (12.8 mg kg^-1, p <0.05) was found in the 0–20 cm layer of the A horizon at the MGfert site (Table 4). Corg concentrations in other types of land use, ranged from 10.6 to 12.7 mg kg^-1, however, the differences between the land use types were insignificant statistically. 20 cm deeper and before the beginning of the AB horizon, Corg concentration ranged from 8.1–8.2 mg kg^-1 in CL soil to 10.0–10.1 mg kg^-1 in MG soil and compared to the 0–20 cm layer decreased by 1.9–3.5 mg kg^-1 or 15.8–27.7% on average.

In this paragraph it is briefly described the changes in Corg concentration in the A horizon (0-20 cm layer and from 20 cm to the AB horizon). Corg concentration changed after the transformation of arable land use into other land uses after 23 years. Also, it is described substantial and insignificant changes are described.

We confirm if the manuscript will be accepted by editorial board – we certainly will take the skillful English editing service checking grammar, spelling, punctuation, and some improvement of style where necessary for an additional charge.

Data completeness: Did the pines produce an organic litter layer, please complete the profile horizon description accordingly and add these Corg to the C stocks

We agree with the remark. Dring 23 years Ap changed into Ah and a 3-4 cm forest flour horizon (O-Ah-AB-B1-B2-1C-C2) was formed in the pine plantation. According that it was changed the profile description in the methodological part: During 23 years Ap changed into Ah in managed grassland, abandoned land and pine plantation. Also, during experiment period a 3-4 cm forest flour horizon (O-Ah-AB-B1-B2-1C-C2) was formed in the pine plantation.

However, we think that it would be incorrect to include the Corg amount of this layer in the Corg total amount of this land use. In our opinion it whould distort the results because our article discusses the amount and variation of Corg in the mineral soil layer.

Data interpretation: 1) it is inappropriate to set CLfert as the comparision basis for changes, because CLfert might differ from the former agricultural soil (e.g. the difference in application of lime might have impact of C dynamics (these are very probable). 2) it is inappropriate to interpret vertical differences in the direction of leaching, because it might just be that the production is vertically different (pH in most soils rather indicate no leaching conditions), mineralisation must also take into accout.

We are very appreciating the reviewer opinion, but we do not agree with this remark and want to motivate our choice of comparison basis for the changes. Also, we want to explain about our choice to write about the leaching.

We disagree with the remark that CLfert cannot be selected to assess changes in soil properties. We believe that in each ecosystem (natural agroecosystem) there is a constant circulation of Corg (destruction, accumulation) and it is natural that the properties of the soil change over the time. To compare the changes in soil properties, we selected the crop rotation of arable land, which is characteristic of the light granulometric soils of our region and the corresponding fertilization, according to the need of plants and soil properties.

Our region is characterized by a washable moisture regime. On average, 36-52% of atmospheric precipitation infiltrates per year (300-350 L m² year^-1). Lysimetric researches have been carried out in our institution since 1972, investigating the effects of various agrotechnical measures on precipitation filtration and leaching of chemical elements (Tyla, Rimšelis, Šleinys, 1997 Leaching of plant nutrients from various soils; Tripolskaja, 2016 Impact of climate variability on precipitation filtration in Lithuania; Tripolskaya, Pirogivskaya, 2013 Impact of climate variability in Lithaunia and Belarus on atmospheric precipitation infiltration: lysimetric study.). Therefore, we confirm that the text about the effect of precipitation infiltration on soil properties was written correctly.

Lysimetric studies have also shown that in Lithuanian climatic conditions 8-10 kg ha^-1 total Corg (Tripolskaya, Booth, Fullen. A lysimeter study of organic carbon leaching from green manure and straw into a sandy loam Haplic Luvisol. Žemdirbystė-Agriculture, 2013, 100(1), so the possible effect of Corg leaching on Corg concentration in different soil layers was discussed in the article.

L 69-70

Introduction:

main point: the state of the art in respect to the main objectives listed in line 69-70 is not clearly stated (text and list of objective do not match).

It has been changed. See the comment below (remark number 4).

L 23

In addition 1) the paper starts with „abandoning“ (line 23), however the study includes not only abandoning but also land use conversion.

We agree with the comment. We write incorrect term. We have changed abandoning into renunciation.

L 26

In this resecpt the hint to agro-ecosystems (line 26) is not appropriate.

See the answer above (L 23).

2) all statements to Corg pools should be deleted (in the whole manuscript) as this study does not include those pools.

It has been deleted word pools and changed into stocks.

3) What is meant by “relative stability of soils”? Please explain more precisely.

Here is a statement from a reference [24] source that humic substances and their fractions help to maintain stable soil properties (chemical, physical, etc.), of which humic acids and humin are the most important. Reference [24] now it is reference [33].

4) The third aim of the study “evaluation of HS leaching” has to be deleted because the authors cannot conclude to leaching from different vertical HS distribution in soils (see also overinterpretation).

The introduction has been rewritten and we added some new sentences (after L34):

Corg accumulation and distribution in the soil profile is associated not only with the root architecture of plants [12] but also with the leaching of organic compounds into the deeper soil layers under the leaching moisture regime [13,14]. Depending on the soil, climatic conditions, agrotechnical measures, leaching of Corg may vary from 8-10 kg ha^-1 year^-1 [15] till 170-310 kg ha^-1 year^-1 [16].

It has been added some new references:

12. Nielsen, K.L., Lynch, J.P., Jablokow, A.G., Curtis P.S. Carbon cost of root systems: an architectural approach. Plant Soil 1994, 165, 161–169. https://doi.org/10.1007/BF00009972

13.  Watkins M.D., Hulugalle N.R., Weaver T.B., Finlay L.A., McCorkell Leaching of dissolved organic carbon and nitrogen under cotton farming systems in a Vertisol. Soil Use and Management 2019, 35(3), 443–452. https://doi.org/10.1111/sum.12510

14.  Lepistö A., Kortelainen P., Mattsson T. Increased organic C and N leaching in a northern boreal river basin in Finland. Global Biogeochemical Cycles 2008, 22(3), https://doi.org/10.1029/2007GB003175

15. Tripolskaja, L., Booth, C. A., Fullen, M. A. A lysimeter study of organic carbon leaching from green manure and straw into a sandy loam Haplic Luvisol. Zemdirbyste-Agriculture, 2013, 100 (1), 3–8.

16.  Vinther, F.P., Hansen, E.M., Eriksen, J. Leaching of soil organic carbon and nitrogen in sandy soils after cultivating grass-clover swards. Biol Fertil Soils 2006, 43, 12–19. https://doi.org/10.1007/s00374-005-0055-4

According to new literature sources the references numbering has been changed.

Also, we changed the aim: The aim of the research was to determine the quantitative and qualitative differences of Corg accumulation and formed humic substances after conversion of cropped land to other land uses (AL, PP, MGfert, MGunfert) in the humic (A) and AB horizons in Arenosol.

L 77

Material and Methods:

1) Fig. 1t does not show the Arenosol (line 77) and Fig. 1 has no scale and north arrow, additionally a more large-scaled more detailed map is missing.

According to the remark the authors decided to refuse from the figure 1 at all. The numbers of figures have been changed from 1 till 6 into 1-5.

L 84

2) What kind of agrogenetic activity (line 84)?

3) Did the pines produce an organic litter layer, please complete the profile horizon description accordingly and add these Corg to the C stocks (see also completeness).

During 23 years Ap changed into Ah and a 3-4 cm forest flour horizon (O-Ah-AB-B1-B2-1C-C2) was formed in the pine plantation. According that it was changed the profile description in the methodological part.

However, we think that it would be incorrect to include the Corg amount of this layer in the Corg total amount of this land use. In our opinion it would distort the results because our article discusses the amount and variation of Corg in the mineral soil layer. In the 23rd year from the beginning of the experiments, a layer of 3-4 cm forest floor was formed in the pine plantation, the structure of the soil profile changed - O-Ah-AB-B1-B2-1C-C2. In other land uses, only the thickness of the A horizon changed.

It has been written: During 23 years Ap changed into Ah in managed grassland, abandoned land and pine plantation. Also, during experiment period a 3-4 cm forest flour horizon (O-Ah-AB-B1-B2-1C-C2) was formed in the pine plantation.

Tab. 1

4) Table 1 can be deleted, written information on texture (one sentence) is enough (main information is that the texture is the same at all plots so that differences soil properties cannot be ascribed to texture differences.

The Table 1 has been deleted. According that this table has been removed the tables numbering have changed from 1 till 6 into 1-5.

L 121-122

5) Please be careful with the application of the terms “decrease” and “increase” in this context (line121-122), it indicates in the former case that the silt particles were more in former times and vice versa, which is obviously not the case.

L 121-122. An error has occurred in the sentence. The amount of soil particles in horizon A and horizon AB is compared. Corrected: The amount of sand particles ranged from 80.7-83.8% in the A horizon to 85.5-90.2% in the AB horizon, silt particles from 11.2-14.3% to 3.5-9.7%, respectively.

L 123 corrected: According to texture and diagnostics horizon propeties the soil belongs to coarse sand Arenosol.

Tab.1, 3

6) Tab. 1 and Tab. 3 the plots should always appear in the same order (please throughout the text).

L 140-149

7) Where the HS measurements (line 140—149) only done in 2018 (needed for comparison 1995 and 2018)?

In this experiment, 1995 and 2018. soil samples were taken from the 0–25 cm layer for chemical properties determination (Corg, pH_KCl, labile P and K, and other elements). The data are presented in Table 2 (now table 1). To determine the amount and quality of humus, soil samples were taken from 3 layers: horizon 0-20 cm and from 20 cm to AB horizon and from AB horizon. The division of horizon A into 2 layers was made in order to evaluate the influence of plant root system, tillage and possibly leaching on the accumulation of humic substances in the mentioned horizons.

L 145

8) Line 145: the given approach can nothing say about migration, just differences which might be there without any leaching.

It was corrected: Such sampling allowed a more accurate estimation of the distribution of humic substances in the A horizon 23 years after land conversion and the assessment of their accumulation differences to the AB horizon in different types of land use, as well as more accurate calculation of HS (Corg, HAs, FAs) stocks in the A horizon, taking into account their concentration differences at different depths of the A horizon and the thickness of the A horizon.

Tab 3

L 201-204

9) Table 3: What were the differentiation criteria to separate A1 from A2? It is likely that different depths for A2 would be accompanied by different A1 depths. Furthermore, represent the given depths as well the depths of the horizons? If so please state it and better place the table into the result chapter (line 201-204)

L 156

10) Why compost sample (line 156).

It was made a mistake. The word has been changed into soil.

11) I doubt that a humification rate can be calculated by the given calculation. As this equation is not internationally used please add some scientific information about its accuracy. To my opinion given HS fraction and total C can never give an information on a time-depending process. Furthermore the equation produces linear rates which are questionable.

We agree that the process of humus accumulation in the soil is not limitless (never ending) and according to some specific values ​​the amount of humus in the soil does not increase. The degree of humification was calculated for a 23-year experimental period. We agree that the results may change as the experiment lasts longer. This is also mentioned in our article, citating the results of research by other researchers. The humification rate is calculated according to the formula given in Kwiatkowska-Malina, J. Qualitative and quantitative soil organic matter estimation for sustainable soil management. Journal of Soils and Sediments 2018, 18, 2801–2812. https://doi.org/10.1007/s11368-017-1891-1

L 193-194

12) line193-194: a correlation never ever gives a causal dependence just a relation.

It was corrected: Relationships between Corg concentration and soil granulometric composition were explored using simple liner regression and coefficient of correlation (r) was used as an indicator that the equation fits for the data.

Also, term correlation was changed into relationship in another sentences.

L 89, 121

13) line 89 and121: AL site is not an abandoned site as cutting occurs (factual abandonment would cause tree appearance with impact on C dynamics).

Results:

1) see remark 9, above.

The answer was given above (Table 3 (now Table 2), L201-204).

2) the section starts with the heading Corg stock, however no Corg stock results appear in the following text

We agree with remark and have changed into Corg concentration and stocks.

L 205-215

L 215-222 Fig. 2

3) The section line 205-215 is not appropriate for a result chapter in which solely the own results are presented (please consider this shortcoming in the following). The following text (line 215-222, including Fig. 2) is not at all related to the objective of the study, hence it should be deleted.

We would like to keep a description of the relationship between soil granulometric composition and Corg concentration. There are a lot of scientists who indicate the relationship between Corg content and clay particle content in the soil. Our data show that with a small amount of clay particles in the soil, Corg accumulation can also be associated with mud particles. In addition, the first reviewer had no comments on the presentation of this data in the article. We believe that a brief description of the soil properties at the beginning of the section helps better understand the influence and causality of the Corg sequestration changes. The presented correlations between soil granulometric composition and Corg concentration partially help to explain which soil particles are involved in the sorption of Corg compounds in Arenosol.

L 224-251

4) The text (lines 224-251) gives statements in respect of the Corg contents, the heading does not include this aspect (just points Corg stocks), hence, heading should be extended.

Humus quality studies were carried out only in 2018, so the whole article compares only the differences in Corg, HA or FA concentrations and stocks between the different land uses. We believe that 25 years before if the soil of the experimental area was used in the same way for many years, it had similar soil properties (in 1995 Corg concentration, pH, labile P and K, A horizon thickness were similar in all experimental territory), so the qualitative composition of humus was similar as well. We aimed to compare how differentiated Corg, HA, and FA concentrations and stocks after the transformation of arable land use to other types of land use.

It has been corrected the heading: Corg concentration and stocks

L 224-231

L226

Tab. 4

5) The text (lines 224-231) needs clarification: line 226: higher concentration than what? To what data are, in total the information of Tab. 4 is insufficiently implemented. What are the main results?

Manuscript text was corrected.

Tab. 4

6) Tab. 4 gives no information on the Corg contents at the beginning of the study; these data must be the basis to show the temporal changes.

Table 4 (now Table 3) shows only Corg concentration data of 2018. A comparison of Corg concentration changes in 1995 and 2018 is presented in Table 2 (now Table 1). Results and discussion section discusses only the differences that formed after the transformation of arable land use to other land uses in 2018.

Also see explanation L 224-251.

L 233- 251

L 233

L 233-234

L 236-239

L 248-249

L 252

Tab. 4

7) Similar writing and interpretation problems fill line 233-251: line 233: in which horizon. Line 233-234 I do not understand the context of both parts of sentence. Line 236-239 (and also line 248-249 and 252: is this information from the literature? If so, it no result and should not be part of the result chapter. However, if the authors want to justify their own results, it is an over-interpretation and speculation (leaching not analyzed). Again be aware of the use of the term “decrease”. Humification rates: not shown in Tab. 4. And again: what is the basic message to take home from this section?

Manuscript text was corrected.

The main idea of ​​this section is that Corg accumulation in Arenosol is quite intense, but after 23 years no statistically significant differences were found between Corg concentrations in different land uses, although the trends are clear that faster accumulation occurs in managed grassland and pine plantation. Corg sequestration processes are more reliably reflected in Corg stocks throughout the A horizon, because it is also estimated the change in the thickness of the A horizon due to land use changes.

It has been made a mistake and the Results section is the Results and Discussion section. Thank You for the remark and we are very sorry for the mistake. The names of the section have been changed.

As it was said above our region is characterized by a washable moisture regime. On average, 36-52% of atmospheric precipitation infiltrates per year (300-350 L m² year^-1). Lysimetric researches have been carried out in our institution since 1972, investigating the effects of various agrotechnical measures on precipitation filtration and leaching of chemical elements (Tyla, Rimšelis, Šleinys, 1997 Leaching of plant nutrients from various soils; Tripolskaja, 2016 Impact of climate variability on precipitation filtration in Lithuania; Tripolskaya, Pirogivskaya, 2013 Impact of climate variability in Lithaunia and Belarus on atmospheric precipitation infiltration: lysimetric study.). Therefore, we confirm that the text about the effect of precipitation infiltration on soil properties was written correctly.

Lysimetric studies have also shown that in Lithuanian climatic conditions 8-10 kg ha^-1 total Corg (Tripolskaya, Booth, Fullen. A lysimeter study of organic carbon leaching from green manure and straw into a sandy loam Haplic Luvisol. Žemdirbystė-Agriculture, 2013, 100(1), so the possible effect of Corg leaching on Corg concentration in different soil layers was discussed in the article.

We can bring a citation in this manuscript, but self-citation is not preferred.

L 258-271

L 258

Fig. 3

Tab. 4

Fig. 3

L 277-283

8) Statements: line 258-271 should become shortened and better organized (now: starting with results, than giving interpretation, discussion (which should not be implemented here), followed up with more results. Line 258 replace “accumulation” by “stocks”. Fig. 3 Replace “changes 1995/2018” by “gains 1995/2018”. Tab. 4 and Fig. 3: it is not clear and inconsistent why the authors give horizon data with Corg contents and summarized data for Corg stocks. Delete statements in line 277-283, because this process is not linear, as the data suggest.

It was corrected L 258.

It has been made a mistake and the Results section is the Results and Discussion section. Thank You for the remark and we are very sorry for the mistake. The names of the section have been changed.

L 258.vIt was replaced accumulation by stocks.

It was corrected Figure 3 (now Figure 2).

Table 4 (now Table 3) and Figure 3 (now Figure 2) is used for data submission in one place. These data are representing and described in this section in detail. Also see the answer above for 7 remark.

L 286

L 290-293

L 193-310

9) Statement in line 286 “changed OC quality” can only be done if there is a comparison to the situation in 1995, data base of 1995 is the basis. If not measured (as I assume) all statements on this aspect has to be deleted. Tab. 5 gives no information on the date of sampling. Statements line 290-293: this problem continues: the authors cannot not set CLfert as control, because agricultural treatment here is not the same than before 1995 (e.g. additional liming, 1995 and CLfert might be different and again these statements cannot be given. In the following lines 193-310 the following problems occur (already well explained above): the application of the term “decrease”, “increase”, interpretation/discussion (see above), data direction forward to migration (s.a.).

It has been explained in other lines above.

Fig. 4

10) Fig. 4 is inadequately evaluated.

In our opinion the Figure 4 very clearly visually shows the differences of humic and fulvic acids stocks in A horizon of different land uses. Thank you for the remark, but all authors ask a permission to leave this figure if we have that possibility. According to another reviewer remark we refused the Figure 1, so the numbering of figures has been changed. The figure number have changed into Figure 3.

11) Data of these HS fractions cannot be compared with data from the literature, gained by different fractionation methods (e.g. separating pools by physical methods).

L 330-352

L 342

11) Line 330-352: see above: most obvious: leach (line 342) = over-interpretation.

About leaching see the answer above.

L 356-364

L 365-373

12) Line 356-364: see above: most obvious: setting CLfert as a basis (control). Line 365-373: see above.

We disagree with the remark that CLfert cannot be selected to assess changes in soil properties. We believe that in each ecosystem (natural agroecosystem) there is a constant circulation of Corg (destruction, accumulation) and it is natural that the properties of the soil change over the time. To compare the changes in soil properties, we selected the crop rotation of arable land, which is characteristic of the light granulometric soils of our region and the corresponding fertilization, according to the need of plants and soil properties.

L 376-383

13) Line 376-383 see remark 11 of Material and Method chapter.

As we said earlier, we agree that the process of humus accumulation in the soil is not limitless (never ending) and according to some specific values ​​the amount of humus in the soil does not increase. The degree of humification was calculated for a 23-year experimental period. We agree that the results may change as the experiment lasts longer. This is also mentioned in our article, citating the results of research by other researchers. The humification rate is calculated according to the formula given in Kwiatkowska-Malina, J. Qualitative and quantitative soil organic matter estimation for sustainable soil management. Journal of Soils and Sediments 2018, 18, 2801–2812. https://doi.org/10.1007/s11368-017-1891-1

Discussion:

Content not a discussion, rather a summary. Over-interpretation (see above). In addition: the pointed “best position” of MGfert is only true for the analyzed timespan and for a reached climax situation (other studies show much larger time series of C changes). 

It has been made a mistake and the Discussion section is the Conclusions section. Thank You for the remark and we are very sorry for the mistake. The names of the section have been changed (Discussion into Conclusions).

In the first sentence of Conclusions section, we have added: The results of this study allowed a more accurate assessment of Corg sequestration processes in Arenosol after conversion of cropped land to other types of land use (grassland and pine plantation) in temperate climate zone during 23 years’ time period.