N2-Fixing Tree Species Help to Alleviate C- and P-Limitation in Both Rhizosphere and Non-Rhizosphere Soils in the Eucalyptus Plantations of Subtropical China
Round 1
Reviewer 1 Report
some questions in the attached file
Comments for author File: 
Comments.docx
Author Response
1. Line 130-133. The classical shaking method [23,33] was used to collect the rhizosphere soil (the soil that still adhered to a root within 4 mm after gently shaking the root system by hand), and the rest of the soil was collected as non-rhizosphere soil. To what extent was the shaking force the same each time?
Response: Thanks for pointing this out. We have carefully checked the entire sampling methods and made necessary modification to avoid the confusion. Meanwhile, the more information of classical shaking method was added (Lines 126-130).
2. Line 203. Table 2. Soil characterization in PP and MP. - Maybe should add units of measurement for some indicators (e.g. SOC, TN, TP, AP, etc.)?
Response: Thank you for noticing these errors. We added the correct units in Table 2 (Table 2).
3. What are the sources of mobile phosphorus in red soil?
Response: We acknowledge the reviewer’s good comments and suggestions. Further studies are required to determine the actual effects of N2-fixing tree species on P immobilization and efficiency for eucalypts plantations in subtropical soils. They will help us to identify the potential drivers and propose management practices that could to develop sustainable eucalypt forestry.
Author Response File: Author Response.docx
Reviewer 2 Report
The topics presented in the manuscript are consistent with the profile of the journal. Its structure is correct. The main objectives of study were to assess how the addition of N2-fixing tree species impacts the characteristics of extracellular enzyme activity (EEA) and enzymatic stoichiometry (EES) in both rhizosphere and non-rhizosphere soils, and to pinpoint the environmental factors affecting EEA and EES parameters.
The research was carried out methodologically correctly, well described and interpreted. The conclusions result from the scope of the research performed.
The weakness of the manuscript is the lack of information on the grain size composition of soil samples from individual plantations. Soil grain size is a relatively constant feature and therefore such information could strengthen the interpretation of the obtained results.
Other comments
No information is provided on the extraction of N-NO3 and N-NH4 from soil.
Literature is incorrectly cited on lines 155, 158 and 168.
On line 160, please explain the abbreviation L-DOPA.
Table 1 - in the table caption, the letter R should be placed in brackets after the word rhizosphere, and the letters RH after the word non-rhizosphere.
Table 2 - there are no units for measuring individual soil characteristics and no explanation of the meaning of the abbreviations R and RN.
Figure 1 - on the y axes, please insert information in which chemical compounds the individual activities are expressed. The words rhizosphere and non-rhizosphere should be followed by appropriate letter abbreviations. The note in the last line also applies to other drawings.
Author Response
The topics presented in the manuscript are consistent with the profile of the journal. Its structure is correct. The main objectives of study were to assess how the addition of N2-fixing tree species impacts the characteristics of extracellular enzyme activity (EEA) and enzymatic stoichiometry (EES) in both rhizosphere and non-rhizosphere soils, and to pinpoint the environmental factors affecting EEA and EES parameters.
The research was carried out methodologically correctly, well described and interpreted. The conclusions result from the scope of the research performed.
The weakness of the manuscript is the lack of information on the grain size composition of soil samples from individual plantations. Soil grain size is a relatively constant feature and therefore such information could strengthen the interpretation of the obtained results.
Response: Thanks to the reviewer for the positive comments and a nice summary of our work. The grain size composition carry important information on soil geological history and processes. However, we regret this study did not investigate the grain size composition of soil and we will conduct more relevant studies in the future.
1. No information is provided on the extraction of N-NO3 and N-NH4 from soil.
Response: Thanks for pointing these out. We have added more detailed descriptions of the methods used to determine NO3--N and NH4+-N in Materials and Methods (Lines 141-143).
2. Literature is incorrectly cited on lines 155, 158 and 168.
Response: Thank you for noticing these errors. We have corrected the errors pointed out and corrected the same errors by carefully reviewing the manuscript. (Lines 158-159, 161, 171, etc.).
3. On line 160, please explain the abbreviation L-DOPA.
Response: Thank you for your suggestion. As suggested, we have added the full name of L-DOPA (Line 163).
4. Table 1 - in the table caption, the letter R should be placed in brackets after the word rhizosphere, and the letters RH after the word non-rhizosphere.
Response: Thanks for pointing these out. We have supplemented the abbreviations R and NR in the title of Table 2 (Line 206).
5. Table 2 - there are no units for measuring individual soil characteristics and no explanation of the meaning of the abbreviations R and RN.
Response: Thank you for noticing these errors. We have added the correct units in Table 2 and supplemented the abbreviations R and NR in the title (Line 206 and Table 2).
6. Figure 1 - on the y axes, please insert information in which chemical compounds the individual activities are expressed. The words rhizosphere and non-rhizosphere should be followed by appropriate letter abbreviations. The note in the last line also applies to other drawings.
Response: Thank you for your suggestion. As suggested, we added the enzyme information on the y axis of Fig. 1 and supplemented the R and NR abbreviations in the title. We have carefully examined and corrected the same problems. (Lines 231-232, 246, 259 and Fig. 1).
Author Response File: Author Response.docx
Reviewer 3 Report
The manuscript deals with microbial enzyme activity in forest soils – nutrients, rhizosphere, plantations.
The abstract is well structured but too long. The authors should shorten it to meet the Forest’ Instructions to authors requirements.
The Introduction sufficiently describes the state of the art.
The methods are described in detail. In 2.3, in the last sentence, it is not clear to me the method used for the evaluation of MBC, MBN, and MBP. I propose to clarify.
Author Response
1. The manuscript deals with microbial enzyme activity in forest soils-nutrients, rhizosphere, plantations. The abstract is well structured but too long. The authors should shorten it to meet the Forest’ Instructions to authors requirements.
Response: Thank you for your comments. We read the abstract carefully and condensed it without compromising its structural integrity in order to improve its readability. (Lines 19-25).
2. The Introduction sufficiently describes the state of the art. The methods are described in detail. In 2.3, in the last sentence, it is not clear to me the method used for the evaluation of MBC, MBN, and MBP. I propose to clarify.
Response: Thank you for your suggestion. As suggested, we describe in detail the methods for microbial biomass determination in Materials and Methods (Lines145-154).
Author Response File: Author Response.docx
