Huiyu Kang, Zhengyong Yang, Zhiyi Zhang

College of Economics and Management, Shanghai Ocean University, Shanghai, 201306, China

Keywords:Seaweed products Trade competitiveness index International competitiveness

A B S T R A C T China is the most productive seaweed farming country in the world and her seaweed imports and exports have a significant impact on global seaweed trade commodities and food security.Nevertheless, few studies had delved into the main characteristics and development of China’s seaweed farming industry.This paper aims to narrow this research gap by analyzing trade patterns in China’s seaweed products and the international competitiveness of seaweed product by using the international market share index (IMS), the trade competitiveness index (TC),and revealed comparative advantage index (RCA) from 2002 to 2017.The results showed that Japan, the Association of Southeast Asian Nations (ASEAN), Chile, Peru, and the Republic of Korea are China’s main trade partners, the total trade value of China’s seaweed products has grown rapidly, its imports have gradually exceeded exports, the trade deficit continues to expand, and its competitiveness keeps decreasing.The reasons for this trend may include the changing seaweed trade commodity structure, product differentiation, increased government support in competing countries, and trade barriers among the trade partners.We propose actively expanding international trade markets, establishing a strong seaweed product processing industry to develop high value-added seaweed products, optimizing the trade commodity structure, and differentiating of seaweed products to improve the competitiveness of China’s seaweed products.

1.Introduction

Since the beginning of the 21st century, China’s seaweed industry has boomed and its structure has changed rapidly.In 2017, the country produced 17.50 million tons of seaweed, accounting for 53.75% of the world’s production (Table 1).The ongoing expansion of China’s seaweed industry and continuous evolution of international trade impacts the global seaweed industrial chain, global food security, aquaculture development, and the environment.China’s agricultural products and their trade, such as processed aquatic products, pork, and lamb, have been frequently discussed (Zhou and &Fan, 2009; Wang et al., 2015; Liu, 2006; Chen et al., 2010; Viet, 2020), yet fewer studies have focused on China’s globally significant seaweed imports and exports.These studies mainly focus on the market for seaweed products(Anon, 1981; Bixler & Porse, 2011; Naylor, 1976; Suchart, 1996; Yemenicioglu et al., 2020; White et al., 2020) and seaweed industry development and trade policies (Ai et al., 2006; Zhou et al., 2007; Su et al.,2007; Lu et al., 2008; Han et al., 2016; Porse & Rudolph, 2017; Zhong et al., 2017; Buschmann et al., 2017; Campbell et al., 2020; He et al.,2019; Suyo et al., 2021).Few studies investigate the international competitiveness of seaweed products (Sanderson & Di Benedetto, 1988;Yue et al., 2013; Yu et al., 2018; Fan, 2019) and others evaluate the impact of exporting seaweed on residents’ welfare from the perspective of a loss of ecological value (Kong, 2014; Lv, 2017; Ofori & Rouleau,2020; Rebours et al., 2014).

Though previous studies have analyzed the development of the seaweed industry, as well as international trade and trade policies involving various types of seaweed products (such as sea tangle, laver,hydrocolloid, and phycocolloid), there is a lack of research on overall trends in the industry, the competitive landscape, and legal developments regarding international trade for seaweed products.This study analyzes international trade involving China’s seaweed products,the competitiveness of the country’s seaweed industry, and trends in China’s seaweed trade, while exploring possible reasons for changes in those trends.

2.Data and methodology

2.1. Data

This paper used data from the UN Commodity Trade Statistics Database, Food and Agricultural Organization (FAO), and China Seafood Imports and Exports Statistical Yearbook (2003–2018).The information was collected through the available online database or yearbook by using the following keywords, "Seaweed farming and capture production" and "Seaweed export and import production and trade value".Since FAO’s seaweed production data was updated through 2017, the 2002–2017 period was selected across all data sources to ensure uniformity.

2.2. Methodology

2.2.1.Brief description of the methodology

Seaweed products are one part of the overall international trade, so the study of trade issues involving these products must be guided by theories and methods pertaining to international trade.According to the theories of factor endowment and comparative advantage, as well as newer international trade theories, there are many factors affecting international competitiveness across products.Among the indicators for evaluating product trade advantages according to these theories, the most commonly used are the international market share index (IMS), the trade competitiveness index (TC), and the revealed comparative advantage index (RCA).The choice of using these indicators was particularly driven by studies that discussed the international trade of China’s agricultural products (Zhou et al., 2011; Yue et al., 2013; Yu et al., 2018; He et al., 2019), assessed the available competitiveness framework, including production volume indicators or the determinants of competitiveness (Buckley, 1988), used indicators, such as total production volume (farming and capture production), farming area, and the value of imports and exports to assess the development and international trade status of a particular seaweed product in China (Zhong et al., 2017;Han et al., 2016; Yue et al., 2013; Cheng et al., 2011).

Using these studies and the available data from 2002 to 2017, this research used production volume to describe trends of China’s seaweed production, used total trade value and the value of imports and exports to analyze the trends in China’s seaweed trade scale, trade balance, and trade partners.We also measured the impact of different seaweed import and export commodity structures on trade pattern for China’s seaweed industry based on the ratio of the trade value of different seaweed products to the total trade value of seaweed in China, adopted the IMS index to discuss the international market shares of major trade partners in detail, and used TC and RCA indices to analyze the competitiveness of China’s seaweed industry within international trade.

2.2.2.The main indicators of international trade pattern

2.2.2.1.Trade competitiveness index.The Trade Competitiveness Index

(TC) is the ratio of total net exports of certain industries or products of a country and the total amount of imports and exports.It is mainly used to measure whether the products of a given industry in a specific country or region have a competitive advantage over the same products in other countries or regions (Li & Liu, 2020; Liu et al., 2020, pp.86–89).As shown in Equation (1), this index comprises the value of exports of producti,Xi, and the value of imports of producti,Mi

TC’s range is [- 1,1).TC>0 implies a strong international competitiveness, with values closer to 1 indicating a stronger competitiveness,whileTC< 0 signals a weaker international competitiveness and the closer it is to - 1, the weaker its competitiveness.TC= 0 signifies that competitiveness is equal to the international average.TheTCindex can be divided into six levels.0.6 ≤TC< 1 implies a strong competitive advantage; 0.3 ≤TC<0.6 signifies a moderate competitive advantage;0 ≤TC<0.3 signals a weak competitive advantage; - 0.3 ≤TC<0 indicates a weak competitive disadvantage; - 0.6 ≤TC< - 0.3 implies a medium competitive disadvantage; and - 1≤TC<- 0.6 signals a strong competitive disadvantage.

2.2.2.2.Revealed comparative advantage index.Revealed Comparative Advantage index (RCA), created based on Balassa (1965), is the ratio of the value of a country’s exports of a certain product as a percentage of the country’s export value of all products to the global export value of that product as a percentage of the total global export value of all products (Zhang, 2020, pp.33–36), as shown in Equation (2),

whereRCA(Xij) is the revealed comparative advantage of productiin country j;Xiis the total export value of a countryi;Xijis the total export value of productjin a country i;Wwis the world’s total export; andWjis the total export value of the productj.As in Balassa (1965), theRCAindex is scaled into a non-negative range with some important criteria,such asRCA≥2.5 implies strong comparative advantage; 1.25 ≤RCA<2.5 means relatively strong comparative advantage; 0.8 ≤RCA＜1.25，implies general comparative advantage；RCA<0.8 indicates no comparative advantage.This index is generally acknowledged to be the most common index used to measure the competitiveness of a country’s products or industries in the international market (Zhu & Yi, 2007), and is often adopted to quantitatively describe the relative export performance of various industries for a given country.

2.2.2.3.International market share index.The International Market Share index (IMS) is the proportion of a country’s total export value of specific products relative to the global export values for those products.The IMS index measures the position of a certain product or industry in the global market and can reflect variations in the international competitiveness of a certain industry or product for a selected country.A higher value of the index signals a stronger competitiveness of a country’s products.As shown in Equation (3),

whereXijis the export volume of productjof the country andXwjis the trade volume of the productjworldwide.

The most direct way to judge whether a certain product from a specific country is internationally competitive is to determine its share of the international market (Kong, 2011), so this index was also adopted for this analysis.

3.Results

3.1. China’s seaweed production volume

China’s seaweed production generally displayed a steady upward trend from 2002 to 2017.The production of seaweed capture remained stable from 2002 to 2017, while the production of seaweed farming increased from 9.02 million tons in 2002 to 17.53 million tons in 2017 (a growth rate of 51.50%).However, the share of China’s production volume internationally decreased from 70.34% in 2002 to 53.75% in 2017 (Table 1).

3.2. International trade pattern of China’s seaweed products

3.2.1.Total trade value and trade balance

The total trade value of China’s seaweed products has grown rapidly,but the trade deficit continues to expand.The total trade value increased from $123.44 million in 2002 to $449.06 million in 2017.The growth in China’s seaweed export value has been relatively slow.Export value increased from $107.57 million in 2002 to $129.53 million in 2017.In contrast, China’s seaweed imports accelerated significantly, from$15.87 million in 2002 to $319.54 million in 2017.As a result, the trade deficit gradually increased (Fig.1).

Table 1 China’s seaweed production volume and its share in total world production(Unit: millions of tons).

3.2.2.International trade partners

The top 7 trade partners were specifically described by using the total trade value, as well as export and import values of seaweed products.

3.2.2.1.Major trade partners.For China, the trade partners for seaweed products have mainly been Asian countries in recent decades (Table 2).In 2002, the main partners were Japan, ASEAN1, the USA, the Republic of Korea, and additional Asian countries.In 2010, the main partners were Japan, ASEAN, Chile, Peru, and additional Asian countries, while in 2017, Japan, ASEAN, Chile, Peru, and the Republic of Korea represented the major trade partners.These top 7 trade partners respectively accounted for 91.22%, 95.90%, and 96.41% of China’s total trade value in 2002, 2010, and 2017.Meanwhile, with the establishment of the China-ASEAN free trade area, China’s seaweed trade with ASEAN developed rapidly, rising from third in 2002 to first in 2017.The top three trade partners in 2017 were ASEAN, Chile, and Peru.

Based on these major trade partners, the IMS index was further used to analyze these partners’ international market shares.China’s share of the international seaweed trade fluctuated from 2002 to 2017, but increased over the latter part of that period (Table 3).China’s IMS has declined from 5.61 in 2002 to 1.83 in 2010, but rose to 3.91 in 2017.Japan’s IMS increased from 0.61 to 1.34 in 2010 and then decreased from 0.04 in 2017.Republic of Korea’s IMS has declined from 1.40 in 2002 to 0.86 in 2010, but then rose again to 0.87 in 2017.In contrast,the IMS of Chile, Peru, ASEAN, and the European Union all gradually increased.The IMS of ASEAN rose from 5.63 in 2002, to 7.83 in 2010,and then decreased to 6.45 in 2017.Chile’s IMS rose from 0.00 in 2002,to 3.60 in 2010, and then fell back to 2.46 in 2017.Peru’s IMS changed similarly to Chile’s.

Table 2 Trends in seaweed trade value with China’s major trade partners (Unit: Million$).

3.2.2.2.Main export markets.China’s main export markets are located in Asia.China’s seaweed exports to Japan showed a downward trend from 2002 to 2017 (Table 4).Nevertheless, Japan was still China’s top export market.However, exports to ASEAN have grown the fastest as this region escalates from sixth in 2002 to third position in China’s seaweed export markets in 2017.These 8 trade partners accounted for 98.80%, 97.18%, and 95.29% of China’s total exports in 2002, 2010,and 2017.

3.2.2.3.Main import markets.The import markets of China’s seaweed products were constantly changing from 2002 to 2017.In 2002, the main import markets were Chile, ASEAN, the Republic of Korea, and Japan.However, in 2017, the main import markets were ASEAN, Chile,Peru, the Republic of Korea, and Japan.ASEAN, Chile, and Peru(Table 5) have been relatively stable import markets.These countries respectively accounted for 48.25%, 31.20%, and 10.38% of China’s total imports in 2017.ASEAN has further advanced as China’s most important import market.

Fig.1.China’s seaweed trade value trend from 2002 to 2017(Source: Food and agricultural organization, 2002-2017).

Table 3 The change of international market share index (IMS) of major trade partners.

Table 4 Trends in China’s seaweed major export market for seaweed products (Unit:Million $).

3.2.3.Commodity structure

3.2.3.1.Commodity structure of exports.China’s seaweed commodities exports changed significantly from 2002 to 2017.The main products exported in 2002, were "sea tangles and salted" and "other seaweed and other algae", which respectively accounted for 58.04% and 41.81% of total exports (Table 6).In 2017, they became "other seaweeds and algae,prepared or preserved", "laver dried, flavored, and others", "sea tangles and salted", and "Laminaria japonicadried, fresh, salted, and others",which respectively accounted for 36.98%, 35.73%, 13.78%, and 11.90%of total exports.

Table 5 Trends in China’s major import markets for seaweed products (Unit: Million $).

3.2.3.2.Commodity structure of imports.The import structure of China’s seaweed commodities also changed greatly from 2002 to 2017.In 2002,the main imported seaweed products were "Other seaweed and other algae" and "Sea tangle and salted", contributing 95.56% and 4.38% of the total value of imported seaweed products.In 2017, the main imported commodities were "unfit for human consumption of seaweed and other algae", "Eucheuma dried and others", and "laver dried, flavored,and others", which accounted for 31.21%, 26.00%, and 33.27% of total value of imports, respectively.These 3 commodities were the most important seaweed goods imported to China (Table 7).

3.3. Competitiveness analysis

Since the competitiveness of China’s seaweed product decreased and the trade deficit expanded, we used the trade competitiveness index to look at the international competitiveness of China’s seaweed product in detail.Owing to the fact that the seaweed trade value of the top seven 7 partners accounted for about 90 percent of global seaweed trade value in recent years, only the seaweed competitiveness of main trade partners was analyzed.

3.3.1.The TC index of the World’s major countries and China’s major seaweed products

Pertaining to the seaweed trade, China dropped its status from a strong competitive advantage to one with a strong competitive disadvantage, with theTCindex continuing to decrease from 0.72 in 2002 to- 0.75 in 2017.Among the main seaweed suppliers worldwide, theTCindices of Chile, the Republic of Korea, ASEAN, and Peru were positive,indicating a strong competitive advantage of their seaweed products from 2002 to 2017.Peru took the lead with a trade competitiveness index above 0.90.For Chile,TCfell from 0.86 in 2002, to 0.74 in 2010,and then rose again to 0.82 in 2017.The value of the index of the Republic of Korea decreased from 0.72 in 2002, to 0.70 in 2010, but then rose again to 0.87 in 2017.Japan showed a strong competitive advantage overall during the sampled period.For ASEAN,TCsoared from 0.11 in 2002, to 0.30 in 2010, and then fell to 0.24 in 2017, which signaled a weak competitive advantage.In addition, theTCindex of the European Union gradually increased from - 0.55 in 2002 to 0.40 in 2017, which indicated a medium competitive disadvantage to a medium competitive advantage.The index of Japan rose from - 0.81 in 2012, to - 0.76 in 2010, and then decreased to - 0.85 in 2017, which signified a strong competitive disadvantage in international trade of seaweed products(Table 8).

However, for China, there was substantial heterogeneity in thedevelopment of international competitiveness across different seaweed products.TheTCindex of "sea tangle and salted", "Laminaria japonicadried, fresh, salted, and others", and "other seaweeds and algae, prepared or preserved" were all positive, showing strong competitive advantages in these seaweed products from 2002 to 2017.Especially, "sea tangle and salted" is the product with the strongest trade competitiveness with aTCvalue above 0.90 in 2002–2017.For "Laminaria japonicadried, fresh, salted and others", it rose from 0.00 in 2002, to 0.97 in 2010, and then decreased to 0.92 in 2017.The value of the index of"other seaweeds and algae, prepared or preserved" rose from 0.00 in 2002, to 0.99 in 2017, which means it escalated from a weak competitive advantage to a strong competitive advantage.TheTCindex of"Other edible seaweeds and algae" rose from 0.00 in 2002, to 0.52 in 2017, changing from a weak competitive advantage to a medium competitive advantage.The index of "Laver dried, flavored, and others"increased from 0.00 in 2002, to 0.91 in 2010 and then fell back to 0.10 in 2017, which signified a weak competitive advantage in this year(Table 9).TheTCindex of Nostoc improved from - 1.00 in 2002 to 0.00 in 2017, which indicated that the competitiveness of this seaweed product increased from a status with a strong competitive disadvantage to one with a weak competitive advantage overall.

Table 7 Value percentage of China’s seaweed import commodity from 2002 to 2017.

Table 8 The TC index of the World’s major countries.

Contrary to the above species during the same period, theTCindex of"Unfit for human consumption of seaweed and other algae" dropped from 0.00 in 2002 to - 0.95 in 2017 and the index of "Gracilaria driedand others" decreased from 0.00 in 2002, to - 1.00 in 2010, and then rose to - 0.92 in 2017.The value of the index of "Eucheuma dried and others" fell from 0.00 in 2002 to - 1.00 in 2017, dropping from a weak competitive advantage to a strong competitive disadvantage overall.For"Other seaweed and other algae", TC decreased from - 0.05 in 2002, to- 0.55 in 2010, and then soared to 0.00 in 2017 (Table 9).

Table 9 The TC index of the China’s major seaweed products.

3.3.2.The RCA index of China’s seaweed products

The values of theTCindex show that China’s competitiveness in the global seaweed products market has gradually changed from 2002 to 2017, starting with a strong competitive advantage and transitioning to a competitive disadvantage since 2010.This section uses the RCA index to review the changes in the competitive status of China’s seaweed products from a different perspective.Although China’s RCA index declined from 2002 to 2008, the index was greater than 1.25 over that period, which indicated a relatively strong comparative advantage(Fig.2).Since 2011, China’s RCA index has been lower than 1.25, and by 2017 the index has declined to 0.80, indicating that the country’s seaweed exports do not have a comparative advantage.From a longterm perspective, the RCA index for China’s seaweed products gradually declined from 2002 to 2017, supporting the result observed using the TC index.Although the results of the two measures are somewhat different, both indicated that the international competitiveness of China’s seaweed products declined during this period.

Fig.2.The change of RCA index of China’s seaweed export from 2002 to 2017 (Source: Food and agricultural organization, 2002–2017).

4.Discussion: reasons for the trade deficit and the drop in international competitiveness

4.1. The change of commodity structure

The most significant factor that influenced the international competitiveness of China’s seaweed industry was the trade commodity structure."Unfit for human consumption of seaweed and other algae","Eucheuma dried and others" and "Laver dried, flavored, and others"gradually shifted from exports to full imports over the 2002 to 2017 period, the proportion of import value was significantly higher than that of exports (Tables 6-7).With the rapid development of China’s economy,the demand for materials such as "Eucheuma dried and others" and"Unfit for human consumption of seaweed and other algae" for manufacturing industries increased (Lin, 2005; Liu, 2021; Qin et al.,2021; Xin, 2019; Zhong & Han, 2017), stimulating the import of these seaweed products, which, in turn, contributed to an increasing trade deficit of China’s seaweed products industry (Fig.1).

That export of China’s seaweed products mainly consist of primary products may be another commodity structure-based reason for the fall in international competitiveness.Value-added products, such as medicines and cosmetics produced by American International Special Products Company (ISP) and American FMC Corporation (FMC) accounted for more than 75% of the total production, and Denmark’s Danisco Company was as high as 100% (Zhang et al., 2017), while the proportion of value-added products is comparatively low for China’s seaweed products, accounting for only 22.9% of total production (Qingdao National Marine Science Research Center, 2014).This particular commodity structure may have negatively influenced the competitiveness of China’s seaweed products.

4.2. Influence of trade barriers and industrial policies

Trade barriers may have also contributed to the decline in international competitiveness of China’s seaweed products.China’s seaweed trade gradually changed from a surplus in 2002 to a deficit after 2005(Fig.1).A possible reason for this may be that the world entered into a period of high trade protection regarding the seaweed trade area after 2006.Japan and the European Union have introduced a number of measures and regulations regarding agricultural chemical residues, and food safety and hygiene, which have increased export barriers for China’s agricultural products (He, 2020).The proportion of China’s seaweed products exported to Japan dropped from 65.20% in 2002 to 34.03% in 2017 (Table 4) and the trading partner country/region with the highest level of cooperation changed from Japan to ASEAN(Table 2).Meanwhile, the market share of China’s seaweed products among major trade partners also dropped, from 5.60% in 2002 to 3.90%in 2017 (Table 3).These results may reflect the impact of trade barriers on China’s seaweed trade.

Industrial policies adopted by the governments of trade partners may be other factors that caused the decline of China’s seaweed trade competitiveness.For instance, the government of the Republic of Korea increased the support for the laver industry and included the development of this industry into the national economic development plan(Zhang et al., 2005; Hwang & Park, 2020; Hwang & Park, 2020).Based on this, due to technical trade barriers, most of seaweed products may be blocked from certain national markets, which greatly restricted the export value of China’s seaweed products, contributing to a trade deficit.

4.3. Product differentiation

Insufficient differentiation of the main exported commodities might be another reason for the fall in the international competitiveness of China’s seaweed products, as.Different markets have different needs for products.China’s most concentrated export products are "laver dried,flavored, and others" and "Laminaria japonicadried, fresh, salted, and others", and "Other seaweeds and algae, prepared or preserved"(Table 6).The three most popular seaweed products in Japan were nori(Porphyra), wakame (Undaria), and kombu (Laminaria), and these products were often cooked to flavor dishes or soup stocks before consumption (Theodore & David, 2011).The Republic of Korea had mainly three genera, the brown seaweeds,SaccharinaandUndaria, and the red seaweeds,Pyropia/Porphyra, which represented 96% of the entire seaweed production in the country (Hwang & Park, 2020).Although the properties of seaweed were similar, they were perceived as slightly different consumption products among countries.In the Republic of Korea, the consumption rate of grilled or roasted seaweed was significantly higher than that of other cooking methods (P＜0.01) by adults(MK Choi et al., 2019).In Europe, food and beverage enthusiasts with seaweed flavor increased to 147% during 2011 and 2015, compared to 37% for snacks (Mintel 2016) (Birch et al., 2018).In its development,seaweed was also made into cookie products with 20% seaweed content that was suitable and liked by children (Wijayanto et al., 2017).According to the Sudarwati et al.(2019), global seaweed consumption was higher for direct consumption (40%) as fresh food/salad and indirect consumption through processed food (by 40%) than industrial applications (hydrocolloids) by 20%.At present, China’s seaweed food processing technology mainly involves food, functional foods, beverages,food additives, and condiments in the rough processing stage (Wang et al., 2021), therefore the export of seaweed products may not meet the needs of some countries, which greatly restricted the export value of China’s seaweed products, contributing to a trade deficit.

5.Conclusions and policy implications

5.1. Conclusions

Since the beginning of the 21st century, China’s seaweed industry has kept on booming and its structure has been changing rapidly.Imports and exports also changed substantially from 2002 to 2017.The results show that, although China’s production of seaweed products has increased, its share in global seaweed production decreased from 70.34% in 2002 to 53.75% in 2017.During the same period, with Japan,ASEAN, Chile, Peru, and the Republic of Korea as the main trade partners, the total trade value of China’s seaweed products has grown rapidly, and its imports gradually exceeded exports over 2011 to 2017;as a result, the trade deficit continues to expand.TheTCandRCAindices showed that the competitiveness of China’s seaweed products have been declining.The reasons for the trade deficit and the decline in China’s competitiveness may include the changing trade commodity structure,insufficient product differentiation of the main exported commodities in the last decades, low support by China’s industrial policies, increased government support in competitors, and trade barriers among the partners.

5.2. Policy implications

The international market for China’s seaweed products is relatively concentrated on Japan, ASEAN, Chile, Peru, and the Republic of Korea as the main trade partners.Thus, it is necessary to actively expand the scope of the market to effectively reduce market risks.To this end, one choice may be to expand and deepen cooperation with countries along the "Belt and Road".Trade commodities are mainly concentrated on three major categories: "Laminaria japonicadried, fresh, salted, and others", "sea tangles and salted", and "other seaweeds and algae, prepared, or preserved".It is important to vigorously develop the seaweed product processing industry and extend the seaweed industrial chains.With the development and wider opening-up process of the Chinese economy, China’s imports of seaweed products may keep increasing.Establishing a strong seaweed product processing industry may be an effective and efficient way to improve the competitiveness of China’s seaweed products.By setting up such an industry, China can develop more high value-added seaweed products than ever to optimize the trade commodity structure and develop more differentiated seaweed products to meet the different needs of customers in the target markets.

In the long run, innovation and extension of environmentallyfriendly seaweed farming and processing technologies, education and training for the seaweed farmers and industrial workers, and the development of prestigious trade markets for seaweed products may also significantly influence the competitiveness of China’s seaweed products.

6.Future research directions

This paper first analyzes the trade patterns of China’s seaweed products from 2002 to 2017 and then goes on to estimate the international competitiveness of these products during this period by using the trade competitiveness index.Although the status of international trade and the competitiveness of China’s seaweed products are described, and the reasons for the drop in international competitiveness are preliminarily discussed, more research is needed to uncover the reasons for these changes in competitiveness more precisely.At the same time,different markets for China’s seaweed products may have different characteristics, which need to be explored more and investigated in detail.

CRediT authorship contribution statement

Huiyu Kang:Conceptualization, Methodology, Data curation,Writing – original draft, Writing – review & editing, Investigation.Zhengyong Yang:Conceptualization, Methodology, Writing – review &editing.Zhiyi Zhang:Data curation.

Declaration of competing interest

The authors declare no conflict of interest.

Acknowledgments

Thanks to the financial support of the China Agriculture Research System (CARS-47-G29).The authors are very grateful for Professor Leibrecht Markus and Dr.Boou Chen sincere help and remarks and the valuable comments by anonymous reviewers.Their discussions and suggestions substantially improved the clarity of the manuscript.The authors take sole responsibility for this paper.