Southwest Coast Research Articles

Diapiric Structures in the Tinto River Estuary (SW Spain) Caused by Artificial Load of an Industrial Stockpile

The mouth of the Tinto River is located on the southwest coast of the Iberian Peninsula in the northwest of the Gulf of Cadiz. The river flows into an estuarine system shared with the Odiel River, commonly known as the “Ría de Huelva”. In the 1960s, a wide area of ancient salt marshes was transformed by a stockpile of industrial wastes of phosphogypsum, reaching a height of 35 m above the level of the salt marsh at its highest point. Two surveys using high-resolution seismic reflection in conjunction with a parametric profiler were carried out in 2016 and 2018. The purpose of these geophysical studies was the realization of a 3D model of the sedimentary units constituting the most recent filling of the estuary. The records present abundant extrusion structures located on the margins of the waste stockpiles, which break the visible stratification of the surficial units of the estuary. In some sectors, these structures have reached the estuarine surface and have, therefore, a morphological expression on the estuarine floor. The origin of these structures is interpreted as a vertical escape of fluidized sediments from lower units caused by overpressure from stacking.

Influence of physico-chemical parameters on natural radionuclides in the coastal belt of Kollam district, South west coast of India

Influence of physico-chemical parameters on natural radionuclides in the coastal belt of Kollam district, South west coast of India

Thliphthisasapphus (Rubiaceae, Rubieae), a new species from Lefkada (Ionian Islands, Greece) and its ecological position.

The new species, Thliphthisasapphussp. nov. (Rubiaceae, Rubieae), a narrow endemic of the white cliffs of Lefkátas on the southwest coast of Lefkada (Greece) is described and illustrated and an IUCN assessment is presented. Vegetation relevés were performed at the single known locality, limestone cliffs facing the sea and revealed a new association, the Thliphthisasapphus-Lomelosietumdallaportae. The chromosome number of Thliphthisasapphus was determined as 2n = 4x = 44, being the single tetraploid species in the genus to date. The species also differs markedly morphologically from its morphologically closest relatives, two Greek steno-endemic oreophytes, Th.baenitzii and Th.muscosa by the following characters: densely setose mericarps and corolla, tetraploidy and by its distribution. An identification key for the Greek species of Thliphthisa is provided. Th.sapphus constitutes the westernmost outpost of a group of Greek steno-endemics, highlighting the importance of coastal habitats and their protection as refugia for poorly competitive chamaephytes.

Additional Record and Taxonomic Description of the Arabian Carpet Shark, Chiloscyllium arabicum, from Dholai Port, Southwest Coast of Gujarat, India

Additional Record and Taxonomic Description of the Arabian Carpet Shark, Chiloscyllium arabicum, from Dholai Port, Southwest Coast of Gujarat, India

Population growth, habitat use, and conservation strategies of the Black-faced Spoonbill (Platalea minor) in the southwest coast of Taiwan

Population growth, habitat use, and conservation strategies of the Black-faced Spoonbill (Platalea minor) in the southwest coast of Taiwan

What's in a name? Political and economic concepts differ in social media references to harmful algae blooms

Policies and management decisions in the marine environment are driven in part by public sentiment which can grow more intense during hazard events like Harmful Algae Blooms (HABs). The public conversations on social media sites like Twitter (before X) reveal the polarized nature of HABs through nuanced language and sentiment. This article uses mixed methods of machine learned topic modeling and inductive qualitative coding to describe the ways the long-term 2017–2019 Karenia brevis “red tide” bloom were politicized across Florida's South West coast. It finds that there are topical differences in keywords related to place (e.g. beach, Florida, coast), agent (individual or organization), and epistemic values (reliance on scientific and/or media reports). These topical differences demonstrate different levels of politicization and partisanship in qualitative analysis. Conceptually, this research demonstrates the ways different dimensions of a long-duration marine hazard can be polarized. Regarding management, this research provides insights to political and organizational stakeholders and the gaps in the discourse shaping marine hazards which can be used to strategically guide future social media engagement to manage politicization.What if all the careful work that resource and environmental managers do can be undone by simple, seemingly uncontroversial words? In an era of increased environmental and marine distress—coupled with short format communication—the ways environmental managers choose their words is crucial, even between ostensibly inconsequential nouns like “red tide” or “algae bloom.” Policies and management decisions in the marine environment are driven in part by public sentiment which can grow more intense during hazard events like Harmful Algae Blooms (HABs). The public conversations on social media sites like Twitter (before X) reveal the polarized nature of HABs through nuanced language and sentiment. This article relies on mining social media posts, and uses mixed methods of machine-learned topic modeling and human-driven inductive qualitative coding to describe the ways the long-term 2017–2019 Karenia brevis “red tide” blooms were politicized across Florida's South West coast. It finds that there are topical differences in keywords related to place (e.g. beach, Florida, coast), agent (individual or organization), and epistemic values (reliance on scientific and/or media reports). These topical differences demonstrate different levels of politicization and partisanship in qualitative analysis. Conceptually, this research demonstrates the ways different dimensions of a long-duration marine hazard can be polarized. Regarding management, this research provides insights to political and organizational stakeholders and the gaps in the discourse shaping marine hazards which can be used to strategically guide future social media engagement to manage politicization.

Pelagic Fisheries of India – An overview

The annual pelagic fish landings of the country comprising diverse species, increased from0.3 million t in 1950 to >3 million t in 2021, marking a tenfold increase. The pelagic resourcesconsistently constituted over half of the total marine fish landings. Major contributors tothe pelagic landings are sardines, mackerels, tunas, carangids, ribbonfishes, Bombayduck,codlets, billfishes and barracudas. The west coast of India accounts for 60% of total pelagiclandings with the south-west coast comprising of Kerala, Karnataka and Goa sustainingvast shoals of small pelagic fishes thriving in the nutrient-rich upwelled waters. The pelagicfishes play a crucial role in the marine ecosystem, functioning as both prey and predator.Furthermore, the small pelagic fishes serve as sources of protein-rich food for coastalpopulations, and the large pelagic species command lucrative market prices both in thedomestic and export markets. Continuous monitoring of the landings of pelagic fishes isessential for recommending suitable management plans for the optimal and sustainableexploitation of the available pelagic resources in Indian waters. This paper attempts toprovide an overview of the marine pelagic fisheries of India, based on analysis of the fishlandings data across various sectors spanning the period from 1985 to 2021. Keywords:Marine fish landings, Pelagic fishes, Sustainableexploitation, State-wise contribution, Trends

Diversity of Psammophytes in Sand Dunes of Periyakadu Coast, Southwest Coast of India

The qualitative plant survey in the coastal sand dunes of Periyakadu coast, investigated the current vegetative status of plant life form and its species and families present. The field observations carried out from March 2020 to April 2021. Overall, 126 species belonging to 106 genera and 47 families were recorded in the study area. The most common and dominant families recorded in the study site were: Leguminosae (21species) followed by Poaceae (15 species), Malvaceae (8 Species), Cyperaceae (7 Species), Apocynaceae and Rubiaceae (5 species each). Of these plant species recorded in the study area, 73 Species were herbs, Shrubs (21 Species), Trees (21 species) and Climbers (11 Species). The latter appears to be the case for the plant diversity of the sand dunes under study.

Sediment-water exchange and risk assessment of pesticidal persistent organic pollutants in Bharathappuzha and Periyar Riverine region along the Arabian Sea.

Considering the extensive agricultural practices along the perennial rivers, viz. Periyar and Bharathappuzha of Kerala in the southwest coast of India, the first comprehensive surveillance of new and legacy organochlorine pesticides (OCPs) in surface sediment was conducted. Further, the sediment-water exchange fluxes have been elucidated. Mean concentrations of total HCH, DDT and endosulfan were 0.84ng/g, 0.42ng/g and 0.30ng/g for Bharathappuzha Riverine sediment (BRS) and 1.08ng/g, 0.39ng/g and 0.35ng/g for Periyar Riverine sediment (PRS). The dominance α-HCH and β-HCH isomers in PRS and BRS reflect the ongoing use of technical HCH in Kerala. The calculated KSW in both rivers was very low in comparison with other Indian rivers. The average log K'OC for all the detected OCPs in both the rivers was lower than the predicted log KOC in equilibrium indicating the higher adherence of OCPs to sediment. Furthermore, fugacity fraction (fs/fw) was < 1.0 for all OCPs confirming the net deposition of OCPs into the sediment. Sediment concentrations for each of the OCPs in PRS and BRS did not surpass the threshold effect level and probable effect level as stipulated by the Canadian Council of Ministry of the Environment Guidelines. In addition, all the sites of both rivers had sediment quality guideline quotient (SQGQ) values below 0.1 indicating the absence of significant biological and ecological risks.

Proposed geo-educational activities at the Sidi Bouzid geosite, Safi Province, Marrakech-Safi region, Morocco

The Sidi Bouzid escarpment is one of the geosites that present high educational and tourism values in the Safi Province, extending for several kilometers along the Atlantic coast southwest of the city of Safi, Safi Province, Marrakech-Safi region, Morocco. It offers panoramic views over the town and the Atlantic Ocean, as well as a beautiful beach much frequented by holidaymakers. The sedimentary and paleontological information preserved in the rocks that form the escarpment makes a valuable contribution to paleobiogeographic and paleoclimatic interpretations and stratigraphic correlations on a regional and global scale. This paper focused on promoting and popularizing earth sciences among students at universities, research centers, colleges, schools, and the general public by developing an educational program adapted to the Sidi Bouzid geosite. Survey was employed to collect the data, the results of which was used to evaluate the effectiveness of the educational program. The results showed that the program had a significant impact on all visitor categories since it offered visitors a holistic view of how geological processes shaped the Earth, revealing the interconnections between many components of the Earth system (geosphere, hydrosphere, atmosphere, and biosphere).

Interannual variability of coastal upwelling features along the eastern and western margins of the Arabian Sea

ABSTRACT The Arabian Sea (AS), a basin in the North Indian Ocean (NIO), possesses strong coastal upwelling in its eastern and western margins. The spatio-temporal variability of upwelling over Somalia, Oman and the southwest coast of India is analysed using observed datasets. The spectral analysis of upwelling indices highlights that the semi-annual and annual frequencies were dominant by two orders of magnitude compared with the inter-annual variability over these upwelling zones. The inter-annual variability of coastal upwelling was demarcated with variations in the causative forcing of upwelling associated with the positive modes of Indian Ocean Dipole (pIOD), El-Niño Southern Oscillation (El-Niño) and combined pIOD and El-Niño events over the southwest coast of India (SWCI) and Somalia. Along SWCI, the sea surface temperature and meridional wind stress weakened leading to warming associated with the suppression of upwelling during El-Niño, pIOD and combined events. Along Somalia, the upwelling favourable wind stress showed slight weakening due to pIOD and strong decline due to El-Niño and combined modes. Along Oman, the upwelling favourable wind stress indicated negligible changes due to pIOD, an increase due to El-Niño and a slight decline due to combined modes.

A new species of branchial fish parasitic deep-sea isopod, Brucethoa Aneesh, Hadfield, Smit & Kumar, 2020 (Isopoda: Cymothoidae) from the Indian Ocean, with the transfer of two Elthusa Schioedte & Meinert, 1884 species

Brucethoa isron. sp., a new species of deep-sea cymothoid is described and illustrated from the host fish Spinyjaw greeneye, Chlorophthalmus corniger Alcock, 1894, at depths of 265 to 458 metres from the southwest coast of India. Brucethoa isron. sp. is recovered from the base of the gill cavity, facing the head towards the anterior, and the dorsal body closely adpressed against the gill, while the ventral brood presses against the inner wall of the operculum. Brucethoa isron. sp., the second species of the genus, is characterized by: head weakly immersed in pereonite 1, very elongated body (3.15 times as long as wide); body dorsum not vaulted, almost flat; all coxae short, 0.5 times as the length of corresponding pereonites; sternite 7 with prominent posterior lobes. All adult life stages of the new species are described [including females (ovigerous and non-ovigerous), males, transitional, and juvenile. The species is currently known from the southwest coast of India and is the type locality. Additionally, this research provides valuable ecological insights into Brucethoa isron. sp. and its habitat. As part of the taxonomic contributions, two species, Brucethoa alvaradoensis (Rocha-Ramírez, Chávez-López & Bruce, 2005) comb. n. and Brucethoa epinepheli (Trilles & Justine, 2010) comb. n., are transferred from the Elthusa genus to the Brucethoa genus.

Isolation and Bioactivity Evaluation of Sesquiterpenes from an Alcyonarian of the Genus Lemnalia from the Saudi Arabian Red Sea.

Over the last decades, soft corals have been proven a rich source of biologically active compounds, featuring a wide range of chemical structures. Herein, we investigated the chemistry of an alcyonarian of the genus Lemnalia (Neptheidae), specimens of which were collected from the coral reefs near Al Lith, on the south-west coast of Saudi Arabia. A series of chromatographic separations led to the isolation of 31 sesquiterpenes, featuring mainly the nardosinane and neolemnane carbon skeletons, among which three (13, 14 and 28) are new natural products. The metabolites isolated in sufficient amounts were evaluated in vitro in human tumor and non-cancerous cell lines for a number of biological activities, including their cytotoxic, anti-inflammatory, anti-angiogenic, and neuroprotective activities, as well as for their effect on androgen receptor (AR)-regulated transcription. Among the tested metabolites, compound 12 showed comparable neuroprotective activity to the positive control N-acetylcysteine, albeit at a 10-fold lower concentration.

David versus Goliath? Indigenous people, carbon majors and climate litigation in South Africa

AbstractIn two recent South African cases, Indigenous communities successfully challenged proposed fossil fuel exploration activities by the Shell petroleum company off South Africa's pristine West Coast. In contrast to earlier climate litigation cases in South Africa, the litigants relied specifically on their Indigenous rights and knowledge. In this case note, we highlight the ways in which the two courts engaged with the communities' cultural beliefs and practices as well as their knowledge related to sustainability and how this relates to protecting their livelihoods, cultural practices and identities that are threatened by the proposed activities. We highlight the important role played by Indigenous communities in the climate movement and argue that, in the future, Indigenous and related considerations could provide a strong basis for climate litigation in South Africa and potentially contribute to efforts to protect Indigenous communities against the activities of carbon majors.

Fouling communities from the South African west coast are vulnerable to cooling and ocean acidification

Changing temperature and ocean acidification are well-recognised consequences of climate change in marine systems. In contrast to global trends, the South African west coast is experiencing cooling due to increased frequency and intensity of upwelling. The implications of concurrent cooling and acidification for marine biota are poorly understood, particularly at the community level. This laboratory study assessed how cooling and acidification might affect fouling communities along the South African west coast. Communities were experimentally exposed to two temperatures, 13℃ (current) and 9℃ (cooling), and three pH treatments, 7.9 (current), 7.6 and 7.4, for 18 days. Cooling and acidification altered community structure. Species diversity declined in response to acidification but was not affected by cooling. This was driven by greatest loss of species at 7.4 pH. Notably, acidification reduced the abundance of both calcifying and soft-bodied taxa, highlighting the vulnerability of taxa like ascidians to acidification. Overall, these results highlight the dominant threat posed by acidification, even for alien taxa that are often perceived as resilient to climate change. Additionally, in regions experiencing cooling, acidification may pose a greater threat to fouling communities than thermal changes.

Effect of soil depth on the structure of bacterial composition in the active layer at five geologically distinct sites on James Ross and Vega Islands in Antarctica

Microbial communities in the active layer play a crucial role in the biogeochemical cycles of Antarctic pristine ecosystems. Here, 16S rRNA gene sequencing was used to investigate bacterial communities in active layer of five different geological sites related to the compositional variation of the geological bedrock, including Neogene volcanic or Cretaceous rocks and or marine sediments areas of distinct elevation. Local variations in the thickness of the active layer (50–80 cm) were observed on the Ulu Peninsula, James Ross Island, and the southwest coast of Vega Island, Antarctica during sampling in 2019. High bacterial diversity was detected in all sampling sites. Significant site effects on bacterial composition with increased Chloroflexota and decreased Flavobacteriaceae were only observed between the highest elevation Johnson Mesa 2 plateau and coastal areas. The overall effect of the depth was reflected by the increased of e.g., Cyanobacteria, Propionibacterium, Staphylococcus in the upper surface and Chloroflexota, Acidobacteriota, Actinomycetota at depths below 30 cm. The huge number of unassigned bacteria indicated a potential source of new bacterial species and their ecological role in this extreme environment. For the first time, we showed that the effect of depth on bacterial composition was more significant than the effect of geological bedrock from these previously unexplored regions.

Coastal Ecology and The Christian Fisherfolk of South Asia

Abstract This article studies a Christian fishing community on the southwest coast of the Indian peninsula and explores how it negotiates the deteriorating marine ecosystem. In this process, we get an insight into the inner world of this community whose life, occupation, and faith are deeply intertwined with the ocean and its changes. The fisherfolk’s indigenous wisdom, skill, and religious heritage help them face the threats around them. The article argues that the coastal worldview has much to offer the contemporary world amidst the threat of environmental crisis. The issues raised can offer new perspectives on Christian faith life and show the direction for a rich theology of the ocean.

Estimating blue mussel (Mytilus edulis) connectivity and settlement capacity in mid-latitude fjord regions.

The mussel industry faces challenges such as low and inconsistent levels of larvae settlement and poor-quality spat, leading to variable production. However, mussel farming remains a vital sustainable and environmentally responsible method for producing protein, fostering ecological responsibility in the aquaculture sector. We investigate the population connectivity and larval dispersion of blue mussels (Mytilus edulis) in Scottish waters, as a case study, using a multidisciplinary approach that combined genetic data and particle modelling. This research allows us to develop a thorough understanding of blue mussel population dynamics in mid-latitude fjord regions, to infer gene-flow patterns, and to estimate population divergence. Our findings reveal a primary south-to-north particle transport direction and the presence of five genetic clusters. We discover a significant and continuous genetic material exchange among populations within the study area, with our biophysical model's outcomes aligning with our genetic observations. Additionally, our model reveals a robust connection between the southwest coast and the rest of the west coast. This study will guide the preservation of mussel farming regions, ensuring sustainable populations that contribute to marine ecosystem health and resilience.

Impacts of coastal protection measures along the coast of Kerala, India (through remote sensing techniques)

ABSTRACT The maritime state, Kerala, is located along the southwest coast of the Indian peninsula, which extends from Trivandrum district (8° 17´ 41.03´´ N, 77° 5´ 37.29´´ E) in the South to Kasaragod district (12° 45´ 20.76´´ N, 74° 51´ 58.92´´ E) in the North, exposed to the waves from the Arabian Sea. The shoreline is extremely dynamic due to the impact of waves, tides, currents, coastal orientation and other associated occasional coastal hazards. The annual climatic calendar for the Kerala coast can be broadly classified as South-West monsoon (June to September), North-East Monsoon (October to December), and Pre-monsoon or Non-Monsoon (January to May). Prior to the 2004 Indian Ocean tsunami, a standardised seawall section had been preferred for highly eroding coastal stretches. The coastal hazards in addition to the tsunami impact paved the way for considering several other structures for coastal protection, of which groyne fields have been predominantly implemented. As it is essential to quantify the performance assessment of these protection measures, an exercise using the DSAS (Digital Shoreline Analysis System) tool was carried out, the results of which are presented and discussed in this paper.

Regional Controls on Climate and Weather Variability on the Southwest Coast of Peru

Southwestern Peru has an arid climate typical of subtropical west coasts bordering cold ocean currents. Mountain runoff is barely able to sustain urban needs and motivates this research. Using high-resolution satellite reanalysis products, the meso-scale climate and weather variability are explored via point-to-field regression. A time series spanning 1970–2022 of Tacna area (18 S, 70.2 W, 570 m) rainfall, potential evaporation, wind, and weather parameters were evaluated for thermodynamic and kinematic features. Although sea breezes draw marine air inland, they simultaneously generate low-level divergence and subsidence aloft. Potential evaporation in early summer causes water deficits that are rarely offset by late summer runoff from the Andes Mountains. Winter (May–September) showers from passing cold fronts are more frequent during El Niño. Warming of the tropical east Pacific accelerates subtropical westerly winds that lift over the coastal plains. Quasi-stationary Rossby wave patterns amplify transient troughs at 70 W, but the winter showers rarely exceed 4 mm/day due to low-level stability from negative heat fluxes over cool seawater offshore. Two winter wet spells were studied using satellite and surface data (July 2002, July 2009). Light showers were prominent in elevations from 400 to 900 m. An early summer dry spell was considered (November 2020), wherein southeast winds, coastal upwelling, and low dewpoint temperatures coincided with La Niña conditions. A rain-gauge transect showed that summer convection stays east of the Andes escarpment and seldom benefits the coastal plains. Thus, water resources in Tacna are strained beyond the carrying capacity.