Estimating Forest Aboveground Biomass Combining Pléiades Satellite Imagery and Field Inventory Data in the Peak–Cluster Karst Region of Southwestern China
Round 1
Reviewer 1 Report
Forest ecosystems play a key role in the terrestrial ecosystem carbon cycle, water cycle, and radiant energy exchange. Accurate estimation of forest biomass is the basis for monitoring forest productivity and carbon sink function, which is of great significance for the formulation of forest carbon neutralization strategy and forest quality improvement measures. Karst is a special and precious landform.
In a manuscript submitted by Yinming Guo et al. the authors constructed the BPANN model, by combining very high-resolution satellite imagery and field inventory data for forest AGB mapping in Banzhai Watershed. The study aims was analyse the spatial distribution pattern of forest AGB in typical peakcluster karst regions.
In the literature on the subject, the authors addressed this problem (https://doi.org/10.3390/rs13245030; https://doi.org/10.1007/s11629-017-4760-x). In this respect, the work is not original. However, the manuscript submitted for review provides new data.
However, it is difficult to assess their value, having doubts whether the selected number of analysed squares is sufficient for such a large research area (Detailed comments- point 5)
In view of this, it would appear reasonable for the authors to supplement and clarification the description of the chapter on experimental material and methods (see comments and suggestions), which would allow the assessment of the validity of the presented research results.
Detailed comments:
1. Lines 133: „Evergreen trees mixed with a certain proportions of deciduous trees….”. Please specify the tree species that dominate the composition of karst forests.
In a previous article (https://doi.org/10.1007/s11629-017-4760-x) you wrote: “The dominant tree species of the forests include Platycarya strobilacea, Machilus cavaleriei, Quercus spp., Lithocarpus spp., and Itea spp. Shrubs, such as Pyracantha fortuneana, Coriaria sinica, Rosa cymosa, Rhamnus parvifolia, and Zanthoxylum planispinum, are also widely distributed”.
Such information is missing from this manuscript.
2. Lines 135-136: Please indicate examples of rare species giving their Latin names.
3. Lines 113-212: In the text of the manuscript (Chapter Methods and Material) I do not find references to Figures 1c and 1d.
4. Lines 158; 161-162: Please explain the variable abbreviations used, e.g NDVI (Normalized Difference Vegetation Index); EVI (Enhanced Vegetation Index); GNDVI (Green Normalized Difference Vegetation Index); RVI (Ratio Vegetation Index); ARVI (Atmospherically Resistant Vegetation Index); SAVI (Soil-Adjusted Vegetation Index); DVI (Difference Vegetation Index).
5. Lines 190-191: It seems that the use of 70 forests quadrats (20 m × 30 m or 30 m × 30 m) to estimate the aboveground biomass (AGB) in an area of 8443 ha is insufficient.
6. Line 200: “OR” please expand the abbreviation.
7. Please enlarge figure 3 is not very legible.
8. Table 1. Add explanations below the table 1 (table footer). Tables must be auto-explicative. NDVI (Normalized Difference Vegetation Index); EVI (Enhanced Vegetation Index); GNDVI (Green Normalized Difference Vegetation Index); RVI (Ratio Vegetation Index); ARVI (Atmospherically Resistant Vegetation Index); SAVI (Soil-Adjusted Vegetation Index); DVI (Difference Vegetation Index); AGB (Aboveground biomass (t/ha)).
9. Reference Lines 422-580: References not prepared in accordance with the requirements journal Forests.
Author 1, A.B.; Author 2, C.D. Title of the article. Abbreviated Journal Name Year, Volume, page range.
10. The authors did not provide the publication's DOI numbers or the Uniform Resource Locator (URL) in the reference list, consequently making it difficult to find the quoted publication.
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Comments.docx
Author Response
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Reviewer 2 Report
The ms, Estimating Forest Aboveground Biomass Combining Pléiades Satellite Imagery and Field Inventory Data in Peak-cluster Karst Region of Southwestern China by Guo et al., discusses a study conducted in the mountainous region of Southwest China, which is known for its significant karst geomorphology. The aim of the study was to assess the forest aboveground biomass in this area, which has importance for understanding carbon storage and cycling in terrestrial ecosystems. The authors used actual measurements and an artificial neural network model called BPANN, which utilized satellite imagery, field data, and land cover information, to estimate the forest aboveground biomass in a specific area called the Banzhai Watershed. The model was trained and validated using actual data, and it achieved relatively accurate results. The study demonstrates a promising method for estimating forest aboveground biomass in karst mountainous areas, particularly in the Southwest China region.
Overall, the ms is quite well written. However, the following errors should be pointed out and should definitely be corrected:
Abstract: I see no direct connection between the first statement in the abstract and the topic itself. This statement can be removed.
Introduction: 'Forests occupy the largest plant communities on the land surface of the Earth,'. Do you mean the area occupied or the number of species?
The idea of paragraphs 67-71 is part of the previous paragraph so they should be merged into one.
72-80 is just a summary of the previous paragraphs so it is pointless.
The following paragraphs (81-112) need to be completely rewritten because they are very elusive and do not clearly present the previous studies and also the objectives of this study.
Materials and Methods: 118-119 add a citation.
115-138 Condense these paragraphs. They are repeating ideas.
Discussion: 224-225 It is a repeating idea in this ms.
This section needs to be redone. Remove paragraphs referring only to other studies not directly related to the results obtained. All these should be moved to the introduction. The results obtained should be clearly highlighted.
The English needs to be checked because there are a few obvious errors.
Author Response
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Round 2
Reviewer 2 Report
Ms has been greatly improved. I found that comments were taken into account and for that I thank the authors.
However, you should revise the paragraph on the diversity of the flora in forests, there are studies that it is not the greatest, the diversity of some meadows is even greater than that of tropical forests: (see Dengler, J., Biurrun, I., Boch, S., Dembicz, I., & Török, P. (2020). Grasslands of the Palaearctic biogeographic realm: introduction and synthesis. Encyclopedia of the world’s biomes, 3, 617-637)
Author Response
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