Spatial Distribution of Timbered Soil Physicochemical Properties and Their Effects on the Vegetation Indices in Tongzhou, Beijing

Comments 1: The removal of weeds and stones may alter the natural soil structure and ecosystem conditions. Please provide a clear justification for this step, as it could impact subsequent measurements, particularly those related to bulk density and nutrient analysis.

Response 1: Thank you for pointing this out. We agree with this comment. For bulk density collection, only surface weeds and stones were removed. Since the nutrient analysis in this study focused solely on soil physicochemical properties, the removal of these components does not affect the results(page 4, lines 149–150).

Comments 2: While storing samples at 2–5 °C is common, microbial activity could persist at this temperature, potentially altering results. Why was freezing at a lower temperature (e.g., -20 °C) not considered, particularly for microbial analysis?

Response 2: Thank you for pointing this out. The storage temperature of 2–5 °C was selected to minimize microbial activity while maintaining the integrity of soil physicochemical properties. Freezing at -20 °C was not adopted due to potential changes in soil structure and moisture content. Additionally, since there was no time for immediate air-drying after sampling, the samples were temporarily stored at this temperature and then uniformly air-dried as soon as possible(page 4, lines 155–157).

Comments 3: The grid size (10 cm x 10 cm) used for calculating plant coverage is appropriate for fine-scale vegetation studies. However, if applicable, provide a rationale for its selection, especially if vegetation types vary in size.

Response 3: Thank you for pointing this out. The plot setup aimed to study low-growing herbaceous vegetation under the forest canopy, which is generally suitable for this grid size(page 4, lines 142).

Comments 4: The depth of soil sampling (0–20 cm) aligns with standard practices, but ensure it reflects the specific objectives of your study.

Response 4: Thank you for pointing this out. The 0–20 cm depth was selected to capture the primary root zone and topsoil layer, where most biological and chemical activities occur. This depth is consistent with the study’s objectives focused on nutrient availability and soil physicochemical properties (page 4, lines 153).

Comments 5: The structural characteristics of soil nutrients are closely associated with plant growth." Consider specifying which structural characteristics are being referenced.

Response 5: Agree. We have, accordingly, revised the sentence on page 2, lines 58-60 to specify the structural characteristics of soil nutrients, such as spatial distribution, physicochemical properties, and availability, that are closely associated with plant growth.

Comments 6: Regional overview map of Tongzhou District" could be expanded to provide context, such as highlighting key features shown in the map relevant to the study.

Response 6: Thank you for your suggestion. We have added annotations to the map to provide further explanations and enhance clarity (page 4, line 134).

Comments 7: Ensure that all citations are relevant to the context of the statements they support. For example, the citation for "The structural characteristics of soil nutrients are closely associated with plant growth" should directly address soil nutrient structures and their effects on plants.

Response 7: Thank you for pointing this out. We have already revised the two references you pointed out in the PDF version, and we have selected the second one. We will carefully review and update the citations to ensure they directly address the structural characteristics of soil nutrients and their effects on plant growth (page2, line 57).

Comments 8: The study is a valuable contribution to understanding the ecological and soil-related dynamics of Tongzhou District. Addressing the minor revisions suggested above will enhance the scientific rigor and clarity of your manuscript.

Response 8: We sincerely appreciate your recognition of our work and will address the suggested revisions to further enhance the scientific rigor and clarity of the manuscript.

Comments 1: 140 - the Objects of research section should be used to describe the sampling sites and provide the coordinates of the sampling points.In addition, a map diagram of the site and selection points should be included in the context of the research. 

Response 1: Thank you for pointing this out. We agree with this comment. Therefore, we have included the explanations in the figure, which can be found in Figure 1, along with the coordinates of Tongzhou District (page 3, line 111).

Comments 2: 151 - it is preferable to illustrate this scheme in the figure. Within the description of the objects of research, it is essential to describe the genetic horizons of soils and provide their morphological characteristics.

Response 2: Agree. We have now included the description of the genetic horizons of the soils and their morphological characteristics, supported by relevant references (page3, line 125).

Comments 3: In the introduction, the significance of soil texture was highlighted; Has the ratio of solids of different sizes in the soil mass been determined? 

Response 3: Thank you for pointing this out. The particle size distribution has not been specifically determined in this study. However, the focus was primarily on analyzing other key soil properties relevant to the research objectives. Future studies may incorporate particle size analysis for a more comprehensive evaluation.

Comments 4: 425 - please provide a source of information. 

Response 4: Thank you for pointing this out. The statement is based on the relevant information from the reports published by the Beijing Land and Resources Bureau and the Third National Land Survey. These sources provide data on the land use distribution in the central area, including the prevalence of cultivated land, the extensive use of artificial fertilizers, and the predominance of grain crops in the region (page15, line 439).

Comments 5: 435 - please indicate which irrigation methods can be used 

Response 5: Thank you for pointing this out. We agree with this comment. Therefore, we use periodic leaching irrigation and drip irrigation as effective methods to manage high EC areas. These methods help in controlling salinity levels and ensuring optimal soil conditions for crop growth (page 15, line 451).

Comments 6: 496 - Please provide a link to the source of information.

Response 6: Thank you for pointing this out. We agree with this comment. The source you requested is: Kato, T., Effects of potassium on cell elongation and division in plants. Journal of Plant Physiology, 2007, 294: 294-298 (page 16, line 511).

Comments 1: Lines 84 and 89: The Authors provide the hectares, acres (line 84),  and mu (line 89) forest area. Please report the area using only one internationally recognized unit.

Response 1: Thank you for pointing this out. We agree with this comment. Therefore, we have converted the 450,000 mu to hectares to ensure the use of a single internationally recognized unit. The revised text is provided below: The total funding needed to keep its 30,000 hectares of woodland is about 1.5 billion yuan annually for Tongzhou District [15] (page 2, line 91).

Comments 2: Please clarify the discrepancy in the height range of the studied plants: the Abstract reports a range of 3.300 – 479.867, whereas the maximum height value in Figure 4b is 447.62. Please explain why negative height values appear in this figure. Additionally, please specify the unit of measurement for plant height. The methodology states that height measurements were performed "using a tape measure" (line 14), but further clarification is needed

Response 2: Thank you for pointing this out.Regarding the discrepancy in the height range: The value of 447.62 reported in Figure 4b corresponds to the predicted maximum height in the region, obtained using ordinary Kriging interpolation. The range reported in the Abstract (3.300 – 479.867) is based on actual measurements, with 479.867 being the maximum observed value in the field. The predicted value from the Kriging interpolation may slightly differ from the actual observed maximum height.

As for the negative height values in Figure 4b, these may occur due to the interpolation method used, where Kriging estimation can sometimes produce values outside the observed range, particularly near the boundaries of the study area.

We have now specified that the unit of measurement for plant height is in centimeters (cm) in the revised manuscript for clarity.

We appreciate your suggestions and have updated the manuscript accordingly.

Comments 3: This section requires thorough revision, including verification of table and figure descriptions, correct numbering, completion of missing captions, font size adjustments, and proper placement within the text (see details below).

1. Tables 2–5 – Please ensure consistency in table titles (e.g., "Statistical Characteristics of Soil Physical and Chemical Indicators" vs. "Statistical characteristic values of soil physical and chemical indicators") and standardize font sizes.
2. Table 4 – There is no reference to this table in the text.
3. Figure 2:

·       Line 314: The text refers to Figure 2-e, but it should be Figure 2-g (TN).

·       Line 317: The text refers to Figure 4-h, but it should be Figure 2-h (pH).

·       Line 327: The TK illustration is labeled as "c", but it should be "e".

1. Line 335: The text refers to Figure 5-b, but it should be Figure 3-b.
2. Figure 4 (a–h): This figure is placed too far from the section discussing its results (lines 365–395). It should be repositioned accordingly.
3. Figure 5: Please specify in the caption which heatmap corresponds to which study area. This figure should also be moved closer to the relevant discussion in the text.
4. Line 346: The text refers to Table 5, but the correct reference should be provided. Please verify and correct the table number presenting "Statistical characteristics of herbaceous plant indicators.”

Response 3: Thank you for pointing this out. We agree with these comments.

For Tables 2–5, we have ensured consistency in the table titles and standardized the font sizes throughout the manuscript (page 6, line 243).

The reference to Table 4 has been corrected, and the table is now properly cited in the text.

Regarding (page 7, line 261).

Figure 2:

a)       We have corrected the reference in line 314 to Figure 2-g (TN).

b)       We have updated the reference in line 317 to Figure 2-h (pH).

c)        After several checks, we have confirmed that the TK illustration is correctly labeled as 'c', and the AN illustration is labeled as 'e'. Therefore, the labeling in the figure is accurate and has not been changed.

d)       In line 335, we have corrected the reference to Figure 3-b instead of Figure 5-b.

e)        Figure 4 (a–h) has been repositioned closer to the relevant discussion section (lines 365–395) for better alignment.

f)        The caption for Figure 5 has been updated to specify which heatmap corresponds to which study area, and the figure has been moved closer to the relevant discussion.

g)       We have verified and corrected the reference in line 346 to accurately refer to the table presenting "Statistical characteristics of herbaceous plant indicators.”

We appreciate your thorough review and believe these revisions improve the clarity and accuracy of the manuscript.

Comments 4: This section requires a thorough revision. The authors should use a numbered list in accordance with standard formatting guidelines.

Response 4: Thank you for pointing this out. We have revised this section and formatted it using a numbered list in accordance with the standard formatting guidelines.