Extraction of 10 m Resolution Global Mangrove in 2022

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

With the intensification of global climate change, humans are increasingly valuing the protection of natural resources. Mangrove forests, as an important component of tropical and subtropical intertidal ecosystems, have attracted much attention in recent years due to their strong carbon sequestration capacity, rich species diversity, and abundant natural resources. The research in this article provides data support for global monitoring of mangrove changes, which is of great significance for mangrove protection and restoration. The author has done a lot of work on the writing of the article, which is commendable, but there are still some shortcomings in the article. It is recommended to revise it before reviewing it. The specific suggestions are as follows:

1，In section 3.2, the author described "Extraction of 10m Resolution Global Mangrove Zoning in 2022". The author studied the region of the world, but only made two small area maps. Why did the author not show the global map but two small areas when presenting the results? Also, is there anything special about these two areas?

2，How did the author determine the correctness of the sample points and exclude randomness after distinguishing between grove and non mangrove forests?

3，Figure 2: In global mapping, it is recommended that the author only leave "°" when adding a latitude and longitude network, and there is no need to leave " ′ " and " ″ ", as well as the compass.

4，The author's research area is global, and the mangrove forests extracted by the author should be the area, but the vector graph displayed is a line rather than an area?

5，Figure 3: The author describes that "The red border represents the global mangrove forest vector map for 2020", and the red border does not represent the global mangrove forest, but only represents the mangrove forest of Sundarbans Park and its surrounding environment. Please pay attention to the wording used. In addition, what does the mangrove forest vector map represent? If it is a boundary, then the vector map in the figure is a straight line rather than a closed figure. If it is not, it represents something else. Please explain clearly.

6，Figure 5 and 6：A schematic diagram of misclassification in the 2020 30m resolution dataset, where the orange area roughly reflects the misclassification of rivers (left image) and bare land (right image 314) as mangroves in the 30m dataset. For ease of identification, this article uses sub meter level satellite images provided by GEE, and the misclassified areas within the 30m resolution image are roughly the same. The red border represents the global mangrove vector map for 2020, and the green part represents the extracted mangrove forest for 2022.

7，The author explains in Figures 5 and 6 that the green part represents the extracted mangrove forest. If it is only green, why is there a change in color depth? Please explain clearly what color depth represents, and if possible, use a color band to represent it.

8，Please highly summarize the conclusion section, which is a summary of the results of this article. In addition, the reasons, significance, and previous research findings should not be included in the conclusion, as this is not the conclusion of this study, but the result of others. For example, "It was found in previous studies that the increase in the area of mangrove forests was mainly affected by human activities," which cites research from others. On the contrary, what is the research result of this article?

9，The language of the article needs to be strengthened, for example, some sentences use "Mangrove forests" while others use "Mangrove forest". Please ask the author to check the details of the article.

Comments on the Quality of English Language

The language of the article needs to be strengthened.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

The paper deals with the extraction of a Mangrove presence mapping at global scale (worldwide) at a 10 meters spatial resolution for 2022. GEE platform with its data and algorithms (i.e., Otsu algorithm) was adopted and the result aims to be an updating of the pre-existent global mapping for 2020 at 30 meters spatial resolution (novelty). This represents a useful outcome. Below my suggestions to improve the paper before its publication.

a) The novelty which characterizes the paper has been expressed clearly only in the Results and Discussion section (exactly at page 8) and cannot be appreciated neither in the abstract nor in the introduction.  Hence, first of all, the novelty must be declared early in the Abstract and Introduction section.

b) Please, check all the citations of authors embedded in the text everywhere in the paper so that they are compliant with the guide for authors of Remote Sensing journal

c) Please, check the caption of Figure 1: it seems to me that green dots stand for mangrove forest and yellow dots as non-mangrove while the the text reports the opposite.

d) Are you using a pixel-based or an object-based data-driven approach for classification? Please, clarify.

e) In 3.3 section you are using the expression "synthesized" referring to the vector maps of each continent: what are you meaning? Please, clarify

f) Please add details about parameters configuration for SVM and RF classifiers considered so to assure reproducibility of your study.

g) Some sentences need to be rephrased as at line 279 "constructed a buffer zone of 1 km in their study is 1 km".

h) The error estimation on the accuracy measure of the mapping obtained must be computed.

 

Comments on the Quality of English Language

Moderate editing of English language required: there are some sentences that need to be re-arranged.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The paper has been highly improved. No other concerns by my side.