Round 1

Reviewer 1 Report

The paper reports a suitability analysis for islands and their surrounding area. Therefore, the standard methodology of multicriteria decision analysis is applied. I am very familiar with is analysis, but I have problems to follow the analysis description in the paper and the interpretation of the results. This are the main reasons for this:

- the authors do not refer to common terms like criteria, etc. when describing their work, they even use the terms differently than in the literature

- The writing style: There are many long sentences that make it difficult to follow. The use of the English language is not acceptable. The paper needs to be carefully rewritten and checked by a native speaker.

- The standard formulas need to be referenced to the literature and the common MCDA textbooks [2], also adjust the terminology to these references.

- The data inputs are not properly described. Therewith the overall analysis is not traceable and the results are untransparent.

Some suggestions to improve the text:

Please provide a succinct definition of “double evaluation”

The literature review in chapter one and two is quite exhaustive, but it basically lists a huge number of papers. There is no obvious order of the papers and, in particular, there is no relation to the contribution of the paper provided. Please relate the mentioned literature to your work! Please describe: How does your work differ to previous studies and what is the new contribution? Also provide some hints how the mentions literature can be ordered or grouped to get a better overview of which topics you actually cited.

Line 120: “…the above research methods…” : which exactly do you mean?

I find the term index rather confusing. If you already have an index as an input, why do you need to conduct this study? What you introduce in table 1 are usually called criteria. See for instance in the literature [1] and [2].

What is the difference between the primary and secondary index?

In table 2 and 3 you refer to “Guidelines for Monitoring and Early-warning Index System and Technical Methods of Marine Resources and Environment Carrying Capacity “ . I can not find this document. Please provide a proper citation.

Figure 3 What is the difference between basic data and graphic data?

I can not make any sense of Table 5 . The figures 4-12 are also rather confusing. Please explain the legend. What is the difference between figures 11 and 12, just the colour scheme seems to be different her.

Figures are hardly readable and the resolution is partly not acceptable (Fig 1, 2, 4 . …. )

[1] Keshkamat, S.S., Looijen, J.M. and Zuidgeest, M.H.P. (2009) The formulation and evaluation of transport route planning alternatives : a spatial decision support system for the Via Baltica project, Poland. In: Journal of transport geography, 17(2009)1, pp. 54-64. https://doi.org/10.1016/j.jtrangeo.2008.04.010

[2] Malczewski, J. (1999): GIS and Multicriteria Decision Analysis. New York: John Wiley & Sons.

Grammatical and writing errors:

· Throughout the paper you repeatedly talk of “the island”. This is grammatically not correct, as you probably in most cases refer to “islands” in general and not a particular island. It should be islands. Even your case study in not on a single island. Therefore, it should probably always be “islands” instead of “the island”

· Lines 56-60: split and shorten this sentence

· Lines 131-134: strange sentence, somehow doubles the content

· Lines 184-189: one very long sentence that does not make scene - split the sentence!

Author Response

1. Comments and Suggestions for Authors (Red)

-The authors do not refer to common terms like criteria, etc. when describing their work, they even use the terms differently than in the literature

-The writing style: There are many long sentences that make it difficult to follow. The use of the English language is not acceptable. The paper needs to be carefully rewritten and checked by a native speaker.

-The standard formulas need to be referenced to the literature and the common MCDA textbooks [2], also adjust the terminology to these references.

-The data inputs are not properly described. Therewith the overall analysis is not traceable and the results are untransparent.

Some suggestions to improve the text:

(1) Please provide a succinct definition of “double evaluation”

Thank you for your valuable suggestion. That has been corrected in this research. The specific modification is as follows:

“Double evaluation”, the abbreviation of the evaluation of resource and environmental carrying capacity and territorial development suitability, is the important basis and prerequisite for the implementation of spatial planning.

(2) The literature review in chapter one and two is quite exhaustive, but it basically lists a huge number of papers. There is no obvious order of the papers and, in particular, there is no relation to the contribution of the paper provided. Please relate the mentioned literature to your work! Please describe: How does your work differ to previous studies and what is the new contribution? Also provide some hints how the mentions literature can be ordered or grouped to get a better overview of which topics you actually cited.

We are grateful for this valuable advice. That has been corrected in this research. The specific modification is as follows:

Influenced by the special characteristics of islands [9,10,11], the sea area around islands is different from other sea areas and faces new challenges in assessing the marine spatial suitability. The unique evaluation method should be proposed according to the characteristics of islands[12,13,14,15,16]. In recent years, experts and scholars have conducted a lot of research on the sustainable development and land-sea coordination, such as connotation [17,18], strategies [19,20], framework [21,22,23] and relevant evaluation indexes of land-sea coordination or sustainable development [24], which have been applied in coastal cities [25,26], ports [27] and spatial planning [28,29]. As a special spatial element of land and sea, research on sustainable development of islands, especially inhabited islands, had focused on the opportunities and challenges of island sustainability [30,31,32], network governance [33,34,35], and ecological protection of islands [36,37]. From the conceptual theory and framework study of sustainable development and land-sea coordination, it has been gradually extended to the measurement of island classification management and the evaluation of the marine space suitability for islands. For example, Zheng et al. [38] based on sustainable development, studied the classified development and management of island from the perspective of the ecological suitability. Liu et al. [39] taking Weizhou Island, Guangxi as an example, considered the traffic data and stock of ecological assets in an allround way and constructed the evaluation index system of ecological assets of land-sea coordination. Liu et al. [40] proposed the strategic suggestions for the land-sea coordinated development in Zhoushan Archipelago New Area from the concept and connotation of land-sea coordination and sustainable development. Huang et al. [41] analyzed how to carry out the construction of Hainan International Tourism Island while adhering to the development strategy of sustainable development and land-sea coordination. Anne et al. [42] from the perspective of sustainable development, discussed the suitable treatment method of land-sea interaction through analyzing how the EU members that implement the EU marine spatial planning command considered the land-sea interaction. Linda et al. [43] taking South Africa as an example, studied how to consider the land & marine ecosystem comprehensively and divided the cross-domain precise scale ecosystem maps in order to promote sustainable development. Achim et al. [44] believed that the sustainable development in coastal zone governance called for the multi-layer governance and new forms of policy integration through comprehensive analysis of literature.

In China, “Double evaluation”, the abbreviation of the evaluation of resource and environmental carrying capacity and territorial development suitability, is the important basis and prerequisite for the implementation of spatial planning [45]. It is an effective way to promote sustainable development of space resources. The suitability evaluation of marine space development is an important aspect of resource and environment carrying capacity evaluation and suitability evaluation. Some experts and scholars have done a lot of research on the evaluation of spaces’ development suitability, which has an enlightening effect on the development suitability evaluation of islands. For example, Wang et al. [46] believe that “double evaluation” provides important references for optimizing the spatial structure of the land and controlling the intensity of land development. Jia [47], Zhou [45] argue that the optimization of land spatial pattern based on “double evaluation” should consider the scale and regional discrepancies, and optimize the technical methods in light of local circumstances.

Some experts and scholars tend to classify areas based on the suitability of development and utilization. For example, Ma et al. [48] analyze suitability with two typical sea categories, namely sea for fishery and sea for construction, and conduct an empirical study taking Wenzhou as an example. Liu et al. [49] evaluate the suitability of the development and utilization of uninhabited islands based on the index system of resources—ecological environment—social development framework. Liu et al. [50] construct the coastal zone “potential-limitation” evaluation index system to evaluate the suitability based on the environmental profits and losses.

Some scholars evaluate and zone from the perspective of ecological protection. For example, Li et al. [51] propose the suitability evaluation method of the small-scale marine space development and zone within the framework of ecosystem services. Tian et al. [52] argue the ecological suitability of the habit quality index, biodiversity index and biological vulnerability index. Jiang et al. [53] update the evaluation system of marine ecology suitability to the complex system of nature-society-economy-ecology. Xiang et al. [54] refer to the ecological suitability of the sea area by habitat structure, habitat function, economic and social conditions, and use of the sea area.

Some scholars assess marine space suitability and zones from different aspects such as ecology and economy. For example, Ye et al. [55] evaluate the suitability of the exploration and development of uninhabited islands in light of the importance of ecological protection and the feasibility of economic development. Li et al. [56] propose the zoning of island exploration and development based on the suitability of a comprehensive evaluation and development of ecology-economy-industry and selected 12 indexes to construct the evaluation index system from geographic location, terrains and landforms, protection status and development status. Huang et al. [57] zone and evaluate islands space suitability through GIS. An et al. [58] zone the functions of the coastal zone according to the space development suitability. Lai et al. [59] construct the suitability evaluation index system of “ecological, production and living spaces” of Southwest Guangxi and North Bay and zoned the ocean and land by “three spaces”.

The above studies have enriched the theoretical connotations and applications of “double evaluation”, “suitability evaluation” and “marine spatial suitability evaluation” and have steadily expanded from the land suitability evaluation to the sea and even to islands. Different from the study of the above scholars, more attention is paid to the marine spatial suitability for islands in this research, and a suitability evaluation model is constructed to evaluate the spatial suitability of waters around islands.

(3) Line 120: “…the above research methods…” : which exactly do you mean?

Thank you for your valuable advice. That has been corrected in this research. The specific modification is as follows:

In view of natural resource endowment and characteristics of the sea area around Pingtan Islands, this research conduct a comprehensive suitability evaluation of marine space of the waters around Pingtan Islands.

(4) I find the term index rather confusing. If you already have an index as an input, why do you need to conduct this study? What you introduce in table 1 are usually called criteria. See for instance in the literature [1] and [2]. What is the difference between the primary and secondary index?

Thanks for your value comments.

The primary indexes are comprehensive indexes. The secondary indexes are the refinement and interpretation of the e primary indexes, which shows how the primary indexes is calculated. That has been corrected in this research base on literature [1] and [2].

Theme	Criteria	Explanation
Marine ecological suitability (G1)	Marine resources evaluation (G11)	Resource effect index
Marine ecological suitability (G1)	Marine environment evaluation (G12)	Water quality
……

(5) In table 2 and 3 you refer to “Guidelines for Monitoring and Early-warning Index System and Technical Methods of Marine Resources and Environment Carrying Capacity “ . I can not find this document. Please provide a proper citation.

We deeply appreciate the reviewer’s suggestion. We should apologize about these problems.

That has been corrected in this research. The specific modification is as follows.

[83] Monitoring and Early-warning Technical Methods of Resources and Environment Carrying Capacity (Trial), Ocean and Fishery 2016,0(11),16.

(6) Figure 3 What is the difference between basic data and graphic data?

Thank you for your valuable comment.

Graphic data refers to vector data, pictures, etc.

Basic data refers to statistical data, such as area, length, etc.

(7) I can not make any sense of Table 5 . The figures 4-12 are also rather confusing. Please explain the legend.

Thank you for your valuable advice. We apologize for these problems.

The three types of suitability evaluation values are divided into three levels: high, middle and low. Each space unit is judged to belong to which type of marine space (marine ecological space, marine agricultural production space, marine construction space) according to its levels of three types of suitability evaluation values.

(8) What is the difference between figures 11 and 12, just the colour scheme seems to be different here.

Thanks for your value comments.

Figure 11 is a schematic diagram of three types of space zoning in Pingtan marine space.

Figure 12 is “Two spaces and one red line” of Pingtan marine space. Among them, “two spaces” refers to marine utilization space and marine ecological space, “one line” refers to the marine ecological red line. The marine utilization space includes marine agricultural production space and marine construction space. “Two spaces and one red line” is the mainstream marine spatial layout implemented by China at present

(9) Figures are hardly readable and the resolution is partly not acceptable (Fig 1, 2, 4 . …. )

We are grateful for the suggestion and have reviewed the issue.

The legend and resolution have been changed. (Fig 1, 2, 4-12)

Grammatical and writing errors:

(1) Throughout the paper you repeatedly talk of “the island”. This is grammatically not correct, as you probably in most cases refer to “islands” in general and not a particular island. It should be islands. Even your case study in not on a single island. Therefore, it should probably always be “islands” instead of “the island”

Thanks for your value comment.Actually, that has been corrected in this research.

(2) Lines 56-60: split and shorten this sentence

That has been corrected in this research. The specific modification is as follows.

Chinese territorial spatial planning is currently in the process of forming, and coastal zone planning has become a special planning project with binding and guiding effects on the sea as part of this process. Considering the characteristics of the spatial and ecological environment of islands in spatial planning is particularly important. Therefore, this paper proposes a method for evaluating the marine spatial suitability of islands. It evaluates the spatial suitability of the sea area around Pingtan islands in order to provide useful references for land-sea coordination and sustainable development of island spaces.

(3) Lines 131-134: strange sentence, somehow doubles the content

That has been corrected in this research. The specific modification is as follows.

Spatial suitability evaluation for islands refers to the evaluation of suitability of the sea area around islands for marine ecology, agricultural production and urban construction. Three types of marine spaces are clearly defined, including marine ecological space, marine agricultural production space and marine construction space.

(4) Lines 184-189: one very long sentence that does not make scene - split the sentence!

That has been corrected in this research. The specific modification is as follows.

The purpose of this article is to investigate the different attributes and characteristics of marine ecological space, marine agricultural production space, and marine construction space from the perspective of marine spatial classification. Meanwhile, it also draws upon the "double evaluation" index system [48] and considers the data accessibility and representativeness of the indexes, and finally selects appropriate evaluation indexes scientifically, as illustrated in Table 1, for the construction of the zoning suitability evaluation index system.

Reviewer 2 Report

This paper adresses a relevant issue, which is sustainable development in islands. The study was conducted through evaluation of a proposed index.

Although the submited manuscript provides some important contributions, this work is not ready to be published at this moment. However, I believe that, if the authors perform some important revisions, it may be accepted in the future.

Chapter 1 - Introduction: very poor english writing. The text must be significantly improved in this chapter.

Section 3.1 - Materials: the text in this section does not refer to applied materials. Instead, it introduces the study area and cites the source of the data used in the research. I believe these sources should be cited in the proper citation format. Additionaly, the text structure must be reviewed.

Figure 1: the legend is in very small size, dificult to read. The text resolution is also not clear in the legend.

Line 214 and 215: Please cite the references in the proper format.

Figure 4: Labels in the legend are very small, dificult to read.

Figure 5: Labels in the legend are very small, dificult to read. Te contour of the island is also no visible.

If the authors perform these revisions, I believe this article may be accepted for publication.

This article presents several issues regarding english writing. Although one may notice problems in many parts of the text, the introductory chapter accounts for the more critical problems observed. This chapter must be extensively reviewed and corrected. Perhaps, professional revision may be applied.

Author Response

2.Comments and Suggestions for Authors

(1) Chapter 1 - Introduction: very poor english writing. The text must be significantly improved in this chapter.

We are extremely grateful to the reviewer for pointing out this problem. That has been corrected in this research. This chapter has been corrected and adjusted.

Introduction

Since islands are geographically isolated, have a unique ecosystem, and a fragile natural environment, the high density of exploration and development will be irreversible in the short term [1,2,3]. Developing and protecting islands and the surrounding sea areas in a sustainable manner requires a rational allocation of spatial resources. A marine spatial planning of the sea area around islands can standardize the protection and utilization of islands and facilitate the coordination between their ecological safety and economic development [4,5,6]. Evaluation of marine spatial suitability is a critical element of marine spatial planning of the sea area around islands [7,8], which can provide scientific support. Although it is a comparatively important subject, it has not been adequately studied for islands in China to date. As of yet, there are still problems with evaluating the marine spatial suitability of islands, such as insufficient theoretical support and a lack of detailed technical information.

(2) Section 3.1 - Materials: the text in this section does not refer to applied materials. Instead, it introduces the study area and cites the source of the data used in the research. I believe these sources should be cited in the proper citation format. Additionaly, the text structure must be reviewed.

We deeply appreciate the reviewer’s suggestion.

That has been corrected in this research. And Section 3.1 is changed to study area and date.

3.1. Study area and date

Pingtan Comprehensive Pilot Zone is located in the central coastal region of Fujian Province and west of the north entrance of the Taiwan Strait. The land area is 371 square kilometers, the sea area is 2873 square kilometers, mud flats are 62.93 square kilometers and the coastline is 447square kilometers. Known as “a county with thousands of islands”, Pingtan Comprehensive Pilot Zone consists of 126 islands including Haitan Island and 702 rocks, with an area of 371 square kilometers. With twists and turns along with coast-line, there are 283 gulfs and harbors. The main island, Haitan Island, covers an area of 271 square kilometers, which is the 5th island in China and the first in Fujian Province.

Under the territorial spatial planning system, land-sea coordination is the most effective method of resolving conflicts between land and sea in Pingtan Islands. Besides effectively managing the relationship between islands land area and marine space, it also is capable of promoting the efficient use of land and sea sources and optimizing their al-location. In view of natural resource endowment and characteristics of the sea area around Pingtan Islands, this research conduct a comprehensive suitability evaluation of marine space of the waters around Pingtan Islands, with the data from Marine Function Delineation of Pingtan Comprehensive Pilot Zone, China Marine Statistical Yearbook, Bulletin of Marine Ecology and Environment Status of China, Environmental Quality Bulletin of China’s Coastal Waters, Fuzhou Statistical Yearbook, Bulletin of Ecological Environment Status in Fuzhou and the right confirmation data of the sea area in Pingtan.

(3) Figure 1: the legend is in very small size, difficult to read. The text resolution is also not clear in the legend.

We agree with the comment. That has been corrected in the paper.

(4) Line 214 and 215: Please cite the references in the proper format.

Thank you for your valuable advice. We apologize for these problems. That has been corrected in this research.

[83]Monitoring and Early-warning Technical Methods of Resources and Environment Carrying Capacity (Trial), Ocean and Fishery 2016,0(11),16.

(5) Figure 4: Labels in the legend are very small, difficult to read.

We agree with the comment and have checked it. That has been corrected in this research.

Figure 4. Evaluation results of marine resource effect indexes.

(6) Figure 5: Labels in the legend are very small, difficult to read. The contour of the island is also no visible.

We deeply appreciate the reviewer’s suggestion.

That has been corrected in this research.

Figure 5. Evaluation results of marine development effect index.

Comments on the Quality of English Language

This article presents several issues regarding English writing. Although one may notice problems in many parts of the text, the introductory chapter accounts for the more critical problems observed. This chapter must be extensively reviewed and corrected. Perhaps, professional revision may be applied.

We should apologize about these problems. That has been corrected in this research. This chapter has been corrected and adjusted.

Reviewer 3 Report

Generally paper is very well prepared, but there is few aspects that can be improved. It miss global context and an emphasis on contribution of this approach on similar areas. Please explain the reason you have chosen so big spatial unit/grid cell (2*2km)? The results would be much precise if you had chosen smaller grid cell. Also, article misses detailed explanation how the 20 experts /participants have been chosen for the AHP analysis. In Figure 1 (location) pilot zone should be zoomed/enlarged more. Maps, figures 4-12 are graphically hard to read- what is land what is water? Also legends are different, and it could be misunderstood without explanation of classes distribution.

Author Response

3. Comments and Suggestions for Authors

(1) Please explain the reason you have chosen so big spatial unit/grid cell (2*2km)? The results would be much precise if you had chosen smaller grid cell.

Thank you for your valuable advice.

Because the spatial scale of some data is large and its precision is not enough, spatial unit/grid cell(2*2km) is chosen in this research, such as resource effect index.

(2) Also, article misses detailed explanation how the 20 experts /participants have been chosen for the AHP analysis.

We agree with the comment and have checked it.

That has been corrected in this research. The specific modification is as follows.

20 experts are selected from the marine think tank of National Marine Data and Information Service based on their authoritativeness and study fields. Among them, 5 experts are in the field of marine management, 5 experts are in the field of marine economy, 10 experts are in the field of spatial planning. In this paper, these 20 experts were invited not only to select the primary indexes and finally determine the index system, but also to score the secondary indexes with 1-9 scoring method and check consistency with Python, with CR lower than 0.1.

(3) In Figure 1 (location) pilot zone should be zoomed/enlarged more.

That has been corrected in this research.

(4) Maps, figures 4-12 are graphically hard to read- what is land what is water? Also legends are different, and it could be misunderstood without explanation of classes distribution.

Thank you for your valuable advice. We apologize for these problems. That has been corrected in this research. (Fig 4-12)

Review Reports

1. Comments and Suggestions for Authors (Red)

2.Comments and Suggestions for Authors

3. Comments and Suggestions for Authors