Where and how can Africa and India leverage the blue economy opportunities of the Indian Ocean region as a driver for sustainable development and partnerships?

A novel ratio algorithm for estimation of pCO2 fields in the Northern Indian ocean region using satellite oceanographic data

The Indian Ocean Region (IOR) plays an increasingly important geopolitical and geostrategic role for the world in the 21st century, especially large countries such as the U.S., India, France, Japan and China. India has maintained a much stronger naval presence than China in the IOR for decades, but the balance is starting to shift. Since 2008, China has significantly increased its naval presence in the IOR, raising Indian concerns about the possibility of military encirclement and raising questions in strategic thinking about China's ultimate goals. The article focuses on analyzing the interests and naval presence of India and China and the naval power competition between the two countries in the IOR, along with the impacts of the above issue on each country and region.

Purpose This paper aims to explore how maritime geopolitical tensions, especially between China and India, exist in the Indian Ocean Region (IOR) and impact the mental health and social inclusion of coastal communities. While most strategic analyses focus on military and economic factors, this research incorporates human security perspectives. Design/methodology/approach Using an interdisciplinary framework that combines developmental psychology, strategic studies and geopolitical field analysis, this conceptual study highlights understudied mental health risks through qualitative case studies and secondary data from the IOR. Findings The results indicate that in regions of militarized maritime development, anxiety, chronic stress, identity displacement and communal fragmentation are becoming more common. Stressors include foreign intervention and strategic uncertainty. A disproportionate number of women, children and displaced workers are impacted. Originality/value This study, to the best of the authors’ knowledge, is one of the first to link psychological health at the grassroots level with maritime security strategy, urges policymakers to incorporate human-centered approaches into regional and national security planning. This study argues that growing strategic anxiety necessitates an integrated approach to national security, one that considers mental health and human security, particularly in regions such as Sri Lanka, the Maldives, Lakshadweep and the Andaman and Nicobar Islands.

Abstract The use of unsupervised clustering methods to classify hydroacoustic profiles with similar structures in the study area, and subsequently divide them into distinct marine regions based on acoustic propagation characteristics, facilitates targeted research on the environmental effects of underwater acoustics in different sea areas. However, many existing methods are limited to clustering based solely on sound speed magnitude, which leads to clusters with limited practical utility and poor robustness across different marine regions. This paper proposes a scaling strategy for ocean sound speed gradients based on acoustic propagation characteristics, combined with a clustering algorithm from machine learning. Clustering analysis was conducted using the climatic sound speed field data from the World Ocean Atlas 2023 (WOA23) North Indian Ocean region, and the Bellhop ray‐tracing model was employed to simulate acoustic propagation effects under different environmental conditions. The results indicate that the sound speed profiles in the study area fall into two broad categories: shallow‐sea and deep‐sea, each of which can be subdivided into five distinct classes based on their sound propagation characteristics. Our method shows enhanced accuracy and provides more intuitive guidance for environmental acoustics compared to conventional clustering techniques.

Zanzibar is a leading hub for the Blue Economy (BE) in the Western Indian Ocean region. The ocean-based economy contributes over 37% to Zanzibar’s GDP, and about 17.5% of women are employed in fisheries and aquaculture (mostly seaweed). However, these ocean-based livelihoods are associated with climate sensitive activities and the effects of climate change. Based on ethnographic qualitative fieldwork in Unguja and Pemba islands, this study builds on interviews with fishermen, seaweed farmers, collectors of molluscs and prawns, and technical officers from the Ministry of Blue Economy of Zanzibar. The findings demonstrate that women’s inclusiveness remains a challenge, since most BE officials—and even local communities—face challenges in operationalizing effective strategies to integrate women into various socioeconomic development. Although most women are well informed of the initiatives that take place in their areas, they have limited participation in capacity building and empowerment efforts that can transform their livelihoods. These limitations are becoming an urgent matter due to population growth, diminishing marine resources, and increasing climate change impacts.

Abstract This article provides an overview and provenance of sources uncovered to-date relating to slavery, especially in the Indian Ocean region, contained the Prize Papers Collection at The National Archives, London. The Prize Papers consist of papers and objects confiscated by the British/English from captured ships as well as legal records from the ensuing court cases at the High Court of Admiralty in London. Presently only partially catalogued, the Prize Papers Project will catalogue this unique “accidental archive” down to document level, making its contents available and searchable in open access and bringing more and more traces of slavery to light. This paper presents examples of sources on slavery, in particular from the recently digitized bound appeals cases from the vice-courts of admiralty in the Indian Ocean region. It contextualizes their genealogy, considers their uses and their pitfalls and explores the opportunities they present for gaining further insight into slavery in this region.

African basil (Ocimum gratissimum L.) is a perennial herb of the Lamiaceae family, commonly called Tchiayo in the local Fongbe language. It is a traditional leafy vegetable that is widely consumed in Benin because of its high nutritional, aromatic and medicinal properties (Kpètèhoto et al., 2017). In 2014, many of these plants were found to be wilting in the INRAB experimental field crop plots. In 2018, wilting of African basil crops was documented in farmer’s fields in the districts of Sèmè-Podji, Ouinhi, Tori-Bossito, Ouidah and Abomey-Calavi in Benin, with a 20–90% disease incidence in 173 African basil crop plots (7.2 m²) out of a total of 1,450 surveyed plots. In January 2025, wilted African basil plants were observed near bacterial wilt-infected tomato field crops in the Ouidah district. Stem sections of wilted African basil plants showed brown xylem with the release of whitish bacterial ooze in water. Plating the bacterial solution on SMSA medium (Engelbrecht, M. C. 1994) revealed bacterial colonies morphologically typical of the Ralstonia solanacearum species complex (RSSC). Koch’s postulates were applied by inoculating a single African basil accession growing in sterilized field soil with two separate isolates from the 2025 collection. Ten plants per isolate were inoculated by drenching the soil around the plant crown with 20 ml of bacterial suspension (108 CFU/ml). Susceptible cv. Akikonkoun tomato and cv. Kpinman gboma plants were also inoculated with the same bacterial suspensions. African basil, gboma and tomato plants drenched with sterile distilled water served as the negative control. The inoculated plants were kept in a greenhouse at 32°C (day) and 28°C (night). The African basil plants started wilting 15 days after inoculation (DAI), with 80% of the plants wilted at 28 DAI, while the gboma and tomato plants started wilting 7 and 5 DAI, respectively, and 90% and 100% of these plants had wilted at 28 DAI. The negative control plants remained asymptomatic. No typical RSSC colonies were recovered from control plants, whereas typical RSSC colonies were consistently re-isolated from all inoculated plants, including both symptomatic and latently infected individuals. ImmunoStrip assays (Agdia Inc., Elkhart, IN, USA) and diagnostic PCR using 759/760 primers (Opina et al, 1997) confirmed the RSSC identity of the two selected isolates. A phylotype-specific multiplex PCR (Fegan and Prior 2005) classified the African basil strains in R. pseudosolanacearum phylotype I. The RUN8084 and RUN8085 strains were both typed as sequevar I-31 through phylogenetic inference according to Cellier et al. (2025) (endoglucanase GenBank accession nos. PX273783 and PX273784). This sequevar has been reported to be epidemiologically widespread in southwest Indian Ocean and African regions (Cellier et al. 2023), while showing high geographical and host adaptiveness. This is the first report of R. pseudosolanacearum causing bacterial wilt on O. gratissimum anywhere in the world, especially in Benin. Further surveys are needed to assess the distribution of bacterial wilt on African basil in Benin and to reduce epidemic risks by designing a disease management plan to avoid African basil rotations with solanaceous crops hosting R. pseudosolanacearum.

A new species of scleractinian coral of the genus Truncatoflabellum Cairns, 1989 (Family Flabellidae), Truncatoflabellum madrasensis sp. nov. was described based on specimens collected from Chennai (east coast of India). The species contains 64 septa and the septal symmetry is in the ratio of 16:16:32. Including this new species, a total of 19 species under the genus Truncatoflabellum were recorded from the Indian Ocean region.

Cocos nucifera L. (2n = 2x = 32), the only species within the genus Cocos, is a diploid perennial oilseed plant belonging to the Arecaceae family, earning its’ title as “Kalpavriksha or Tree of Heaven”. Coconut palm holds enormous cultural, traditional, and economic significance across tropical and subtropical regions. Originating from the land fragments of the ancient Gondwana landmass, coconut has undergone wide geographic dispersal and ecological adaptation, thriving along coastal areas from Pacific regions. Despite its significance, ethnobotanical research on coconut remains limited and coconut cultivation faces increasing threats from rapid urbanization. In India, coconut is deeply integrated into indigenous health systems, used for its ethnomedicinal properties including analgesic, anti-inflammatory, cardioprotective, antidiabetic, antioxidant, antibacterial and immunomodulation. Coconut contains high levels of fatty acids such as caprylic acid (9%), capric acid (8%), caproic acid (5%) and myristic acid (20%) which enhances its potential in nutritional therapy and functional food development. This review integrates phytochemical, pharmacological and ethnobotanical evidence, emphasizing coconut’s potential in food, medicine, and sustainable development. Cocos nucifera L. (2n = 2x = 32), the only species within the genus Cocos, is a diploid perennial oilseed plant belonging to the Arecaceae family, earning its title as “Kalpavriksha” or “Tree of Heaven”. Despite its widespread cultural, traditional and economic importance, ethnobotanical research remains limited and cultivation faces increasing threats from urbanization. Originating from the land fragments of the ancient Gondwana landmass, coconut has undergone wide geographic dispersal and ecological adaptation, thriving particularly along the coastal areas of the Pacific and Indian Ocean regions. In India, coconut is deeply integrated into indigenous health systems, used for its ethnomedicinal properties including analgesic, anti-inflammatory, cardioprotective, antidiabetic, antioxidant, antibacterial and immunomodulatory activities. It is rich in fatty acids such as caprylic, capric, caproic and myristic acids, enhancing its potential in nutritional therapy and functional food development. This review integrates phytochemical, pharmacological and ethnobotanical evidence, emphasizing coconut’s potential in food, medicine and sustainable development.

From the dense body of historical literature on the Indian Ocean region to the recent geopolitical construct of the “Indo-Pacific,” studies centered on the region seem to be partially stuck in a binary of the past and a future that is being understood through a security lens. This article examines migrant worker food spaces in Dubai, Muscat, and Singapore as registers of memory and present-day archives of the Indian Ocean. These migrant worker food places, although transnational, are considered ethnic ghettos rather than deserving participants in a global discourse. By presenting these migrant foodscapes as repositories of a long durée history of the Indian Ocean, these subaltern places are brought into dialogue with the “global” register on equal terms.

This article is an analysis of two early modern legal codes from archipelagic Southeast Asia: the Undang Undang Melaka and Undang Amanna Gappa. Even though legal history of the Indian Ocean region has made some significant strides in recent decades, the early modern legal regimes of archipelagic Southeast Asia have not yet received much attention in existing scholarship of the Indian Ocean world. By analysis of the legal codes of the region and their many iterations, this article attempts to interpret how these laws aimed to achieve a tenuous balance between shore-based political authorities and the floating worlds of the seafarers and argues how these laws, decrees from insular Southeast Asia, form an understudied episode in the genealogy of early modern international maritime law. Through my discussion of early modern legal codes from this region, I also briefly demonstrate how a study of these laws elucidates understudied facets of oceanic migration in the region, especially the constitution of trading diaspora and moral economies of sail and trade.

The five South Asian countries surrounding the northern edge of the Indian Ocean — India, Pakistan, Bangladesh, Sri Lanka and the Maldives — boast diverse marine ecosystems ranging from mangrove deltas to coral atolls. The establishment of binding legal obligations for marine environmental protection has made safeguarding marine ecosystems one of the core issues in the global governance system. Taking a legal and institutional approach, this article analyses the main content and characteristics of the marine environmental protection systems of five South Asian countries. Through text analysis, comparative legal research and case evaluation, it aims to answer three key questions:(1) The degree to which current domestic laws in South Asian coastal countries align with international marine environmental norms.(2) The existing regional cooperation mechanisms and interaction models for marine environmental protection in South Asian coastal countries, based on principles of international law and global best practices. (3) There are structural and enforcement bottlenecks in the legal mechanisms for marine environmental protection and cooperation among South Asian countries. The findings indicate that despite certain advancements, significant challenges remain in building a “blue community” in the Indian Ocean region.

Abstract. To gain a deeper understanding of cloud variability over the Southwest Indian Ocean (SWIO) region, various measurement techniques can be used. Cloud data focused on two main sites (Antananarivo, Madagascar, and Reunion Island) were collected over nearly three years (September 2019 to June 2022) using ground-based all-sky camera and Meteosat Second Generation (MSG) satellite imagery. This study primarily examined cloud fraction, although additional analysis based on cloud types is also needed. Two image processing algorithms were used to estimate cloud fraction by analyzing the camera images: one provided by the manufacturer Reuniwatt, and the other, Elifan, initially developed by CNRS. Their performance was compared to assess their relative strengths. Additionally, comparisons with MSG satellite data were carried out to ensure consistency and evaluate the complementarity of ground-based and satellite observations. Despite differences in methodology, the various data sources showed strong agreement. The results indicate that in Antananarivo, during the dry season, a high morning cloud fraction (∼50 %) is typically observed, which gradually decreases throughout the day. In the wet season (December to April), cloud fraction varies between approximately 30 % and 60 %, with reduced cloudiness observed around midday in October and November. In contrast, in Saint-Denis, Reunion, skies are generally clear in the morning but become increasingly cloudy as the day progresses, reaching up to 80 % cloud fraction during the wet season and around 60 % during the dry season.

Viruses transmitted by biting midge species of the genus Culicoides (Diptera: Ceratopogonidae) affect and threaten human or animal health worldwide. In Mauritius, the risk of virus introduction through imported livestock or travellers is high, while serological evidence has demonstrated the circulation of two Culicoides-borne viruses in domestic ruminants and native deer, namely, bluetongue (BTV) and epizootic haemorrhagic disease (EHDV) viruses. To this day, no data at the main island scale have been published on the diversity and distribution of Culicoides species present in Mauritius. A spatial survey across Mauritius was conducted using black light suction traps (OVI traps) from 10 to 20 April 2023. Nineteen farms were selected to cover a diversity of hosts and environments. The traps were operational from dusk to dawn, with a single night capture per site. While the presence of Culicoides imicola Kieffer and Culicoides enderleini Cornet and Brunhes in Mauritius was confirmed, two additional species were detected, Culicoides kibatiensis Goetgheguer and Culicoides bolitinos Meiswinkel. All species were distributed all over the island. Overall abundance ranged from 4 to 19,764 females, with a mean and median abundance of 2,010 and 352 individuals/night/site. The total number of individuals collected during the study was highest for C. imicola (21,065) and lowest for C. bolitinos (313). All four species are Afrotropical and are suspected or historically known to be involved in BTV and EHDV transmission. While intra-specific morphological variations were detected, genetic analyses did not reveal any cryptic diversity. This work has updated the faunistic inventory of the genus Culicoides of veterinary interest in Mauritius and established a list of 4 Afrotropical species known to be vectors and distributed on the island. The abundance of Culicoides was relatively low as compared to mainland Africa but in the range of other islands in the south-west Indian Ocean region. Further work will investigate the temporal dynamics of the four species to identify high-risk seasons.

ABSTRACT Detection and localization of submarine wakes from synthetic aperture radar images is one of the potential resources for oceanic surveillance. It is challenging to access all real-time SAR images of submarine wakes. Therefore, modelling them is necessary to construct the dataset for detecting submarine wakes using cutting-edge deep learning technologies. This study intends to design an SAR image simulator system that models the SAR imaging of submarine trails considering eclectic sea state conditions, submarine parameters, and radar-looking scenarios. Here, a novel revamped velocity bunching mechanism (RVBM) is adopted to simulate both single- and multi-look SAR images by incorporating the Kaiser-Bessel weighting function. This study simulates the perturbation experienced by the three Indian classes of submarines (Sindhughosh, Kalvari, and Shishumar) on SAR images in the Indian Ocean and Mediterranean Sea regions. The trustworthiness of the proposed SAR image simulator has been confirmed by comparing the results with six independent Sentinel-1 SAR images using a variety of qualitative and quantitative measures.

ABSTRACT This article examines how elite brokers reshape sovereignty and territorial control through mega-infrastructure development in the Indian Ocean region. Through an ethnographic study of the US$14 billion Chinese-funded Colombo Port City development in Sri Lanka, it analyses how presidentially appointed Commissioners exercise unprecedented authority over territorial governance through three interrelated mechanisms: legal-institutional innovation that creates exceptional jurisdictions, physical transformation of maritime space, and economic regulation that engineers specialised zones. These ‘infrastructure brokers’ represent a fundamental departure from traditional development intermediaries who operate at society’s margins. Unlike conventional brokers who mediate within existing frameworks, these elite actors architect new institutional arrangements that simultaneously extend and transcend state authority. Operating at the nexus of state power and international capital, they produce differentiated zones of governance that accommodate global investment while maintaining assertions of national control. By revealing how territorial authority is reconfigured through the intersection of elite agency and spatial production, this analysis contributes to understanding sovereignty’s transformation in an era of mega-infrastructure competition across the Global South.

Abstract The sea surface temperature anomaly (SSTA) in the North Indian Ocean (NIO) region associated with Indian Ocean Basin Mode (IOBM) is well‐known as a key factor in impacting the Tibetan Plateau summer precipitation (TPSP). However, either the commonly used IOBM index or the basin‐mean index of SSTA in the NIO region captures only a small portion of TPSP variability, making it underrated in indicating the TPSP. In this study, we demonstrate a significant and predictable relationship between the NIO SSTA and TPSP, when further considering the NIO pattern diversity. This relationship can be depicted by two physics‐based indices accounting for the diverse NIO patterns, which can effectively capture their distinct spatial features and associated impacts on the TPSP. Such an extended diversity view of NIO provides potential predictability of the TPSP.

ABSTRACT In the late 1970s, for the first time, veterans of Australian diplomacy published multiple books that disputed the fundamentals of the national diplomatic pattern, their projects impelled by what they saw as a “crisis” in foreign policy and its management under the Fraser government. The putative crisis was occasioned by a drastic withdrawal of funding from the foreign affairs and aid sectors, the concentration of foreign policy initiative in the hands of the prime minister, and the rise to prominence of a group of personal political advisers. Alan Renouf and Malcolm Booker both rejected the accustomed and unqualified reliance upon the United States as a security and diplomatic partner, appealing to current developments—notably the Vietnam withdrawal—to indicate waning US will and capability. For Booker, the emergence of Soviet strategic interest in the Indian Ocean region indicated that Australia would be forced to deal with regional powers on new terms; Renouf was more sanguine on the prospects for managing regional relations through a middle-power strategy. In the trajectory of their careers, both Renouf and Booker were victims of the “crisis” of the 1970s, though estranged by its bureaucratic consequences.

The Indian Ocean Region has emerged as the central locus of geopolitical contestation and strategic aspirations of global and regional powers due to its centrality in international trade, energy transit, and security concerns. This article looks at the ambitions of key great powers-primarily the United States, China, and India, though Pakistan and other regional powers such as Australia, Japan, and Middle Eastern states also contribute to shaping the IOR's evolving strategic environment. PRC, of late, has increased its footprint in the Indian Ocean Region under the auspices of the ambitious Belt and Road Initiative. This rising Chinese presence in the region is a cause of concern for India, which sees this as an effort to strategically encircle her. This has grave implications for its so-called role as a net security provider in the region and its national security. To counterbalance the Chinese moves in the IOR, India has undertaken a number of actions, which in turn raises the geopolitical anxieties of China, thus prompting her to take counter-reactions. The rationale behind China's strategy to move from near-seas to the far-seas is discussed in this paper. Increasing Chinese presence has made India realize its goal of becoming a major maritime power more aggressively, often taking actions perceived as offensive by China, hence leading to countermeasures. This has ensued a chain of actions, reactions, and counter-actions among these competing states having far-reaching consequences for the region and the world. This research argues that the Chinese footprint is driven mostly by its economic ambitions and finds military aspects associated with the BRI to be perceived threats, given that in reality, China faces many vulnerabilities in the IOR. Thus, it is unlikely that it will build bases with an offensive intention. Instead, the growing Chinese presence in the region could be explained by developing Chinese apprehensions about the security of its SLOCs. Besides, possible areas of cooperation between both India and China and the future of their rivalry are also predicted while suggesting some measures for both of them.