Sanitha K Sivadas

National Centre for Coastal Research · SWQM

The Gulf of Mannar (GoM) includes the GoM Marine National Park and Biosphere Reserve and is globally recognised as a unique marine system with diverse habitat and rich biodiversity. The present study investigated a massive dinoflagellate bloom caused by the green Noctiluca scintillans during September–October 2022 in GoM. Multi-temporal remote sens...

The present investigation focused on studying the phylogenetic position of the green Noctiluca endosymbiont, Pedinomonas noctilucae, collected from the Gulf of Mannar, India. In this study, we re-examined the evolutionary position of this endosymbiotic algae using rbcL sequences. The phylogenetic analysis revealed that P. noctilucae is distantly re...

Three species of polychaetes Magelona falcifera, Polyophthalmus zhadanae, and Ophelina grandis were recorded for the first time from the Indian coast. The species were collected from the intertidal to 5 km distance from the coastline of Palk Bay, Bay of Bengal. The diagnostic features and distributional records of the new recorded species are provi...

The Indian Ocean (IO) continental shelf characterized by unique oceanographic and meteorological features and extreme habitat is a biodiversity hotspot region. Marine biodiversity provides valuable resources and services, in terms of economy, cultural, science, and education. Unsustainable exploitation and habitat degradation represent the greatest...

A regional understanding of beach litter abundance, distribution, and composition is fundamental to formulate strategies to manage litter pollution in a particular area. The present study aimed to quantify and characterize the macro (2.5 cm to 1m), meso (5 mm–2.5 cm), and micro litter (≤5 mm) in the intertidal and backshore area of six sandy beache...

The present study investigates the abundance, distribution, and characterization (shape, size, colour, chemical composition) of microplastics (MPs) in surface water and sediment from the shelf region of the central east coast of India. The surface water and sediment samples were collected at varying depths (12.8–63 m) from 21 locations covering ∼12...

Environmental contamination due to plastic waste mismanagement is a growing global concern. Plastic problem is of particular concern to the Indian Ocean nations as Asia currently contributes to the highest share of mismanaged plastic waste. Consequently, there is a worldwide interest to understand the distribution and transboundary movement of plas...

Biyyam backwater is a developing eco-tourism hub and prone to increased pollution due to urbanization and agricultural waste disposal. This study investigates the distribution, temporal variation, enrichment and accumulation of heavy metals in the surface sediments from Biyyam backwaters. Samples were collected from four locations during post-monso...

In view of increasing Microplastics (MPs) contamination in the marine environment and dearth of baseline data, a study was conducted on the abundance, characterization, and seasonal distribution of MPs in the nearshore sediments of the south-east coast of India. Sediment samples (n = 130) were collected at a distance of 1 km and 10 km from the shor...

The UN Sustainable Development Goal (SDG) 14 sets targets for nations to reduce marine pollution, ocean acidification, and sustainable use of coastal and ocean resources, which requires data on nutrient load, litter/plastics, pH, and biodiversity. Monitoring programs with large-scale and long-term data is an important source of environmental inform...

Coastal upwelling that occurs in the eastern Arabian Sea (EAS) drive the complex dynamics of the food chain. Macrofauna plays a key role in the functioning of coastal ecosystems, but few studies explored the taxonomic and functional patterns of macrofaunal communities under upwelling influence. These patterns have been investigated in this study by...

The objective of this study was to obtain baseline data on litter from three beaches of the Lakshadweep Islands (Kadmat, Suheli Par, and Minicoy). At each site, three transects of 20 × 20 m of the foreshore and intertidal zone were sampled during low tide. All macro litter (size >2.5 cm to <1 m) within each transect were collected and counted. A to...

Phytoplankton, the primary producers in all aquatic systems, plays an important role in key biogeochemical processes that are linked to higher trophic levels and climate variability. The present study deals with the phytoplankton community structure in the Indian Ocean, particularly in the higher latitudes with respect to environmental variables to...

Human-induced loss of biodiversity is affecting the functions and services of the earth's ecosystems. Large regions of the biosphere are expected to be affected by the projected climate change, further aggravating the health of the ecosystems. It has been widely recognized that the successful management of any ecosystem cannot occur without an effe...

Identifying the drivers that shape the biodiversity of a region is important to predict the response of ecosystems to environmental changes. Macrofaunal distribution pattern in the North Indian Ocean has so far been mainly studied considering small geographical areas, and using taxonomic diversity. The present study is a functional trait based appr...

Coastal areas have been centres of human activity for millennia. Though coastal regions contain some of the most vulnerable and fragile ecosystems, they are the sink and often the dumping grounds for a wide range of contaminants. Like most coastal regions of the world, coastal areas of India are densely populated, and ~30% of its human population i...

The first International Indian Ocean Expedition (IIOE; conducted in the early 1960s) was one of the greatest interna- tional, interdisciplinary oceanographic research efforts. It involved 46 research vessels (under 14 different flags) that carried out an unprecedented number of hydrographic surveys (and repeat sur- veys) of the entire Indian Ocean...

Our understanding of coastal biogeography patterns is presently limited to certain regions and marine groups. Comprehending large-scale patterns and their underlying predictors is critical due to the changing environmental conditions. The Indian coast, bounded by two contrasting seas, the Bay of Bengal and Arabian Sea, offers an excellent opportuni...

The objectives of the present study were to evaluate the ecological status of tropical coastal waters using the temperate benthic indices and examine the effect of seasonal variability on the performance of benthic indices. Macrobenthic samples were collected from northwest to southeast coast of India during 2003–2012 and we tested different univar...

In the Arabian Sea, organic matter produced during the upwelling period reaches the seafloor by the end of the monsoon and during the fall intermonsoon period (FIM). Studies on the benthic community is lacking during this period. Therefore, we predict that the FIM period is critical in structuring the coastal benthic community. Results indicated Co...

Temporal variation of macrofauna associated with a marine sponge, Ircinia awn was studied front a tropical rocky shore along,the West coast of India. Triplicate sponge samples (similar to 100 g) were collected from January to December 2010 from Bhagwati Bandar area, Ratnagiri. A total of 122 macrofaunal taxa were found to be associated with the spo...

The present paper examines the functional diversity-environment relation in a placer rich tropical bay. Understanding the environmental variables that determine the biodiversity pattern will help in the effective conservation plans of coastal habitat. However, few studies have been carried out on the biodiversity-environment relation from the diver...

Macrofaunal community structure is determined by a number of environmental variables. The riverine run-off during the monsoon brings about drastic changes in the physico-chemical parameters of a tropical estuary. The aim of the present study was to investigate the influence of rainfall in structuring the benthic macrofaunal community of a tropical...

Kalbadevi Bay in Ratgnairi has been identified as potential site for placer mining along the west coast of India. Since, U. vestiarium is a keystone species of the region; study on some ecological aspect was carried. The paper also discusses the possible impact of beach sand mining and other threats to this ecologically important gastropod. Seasona...

In most ecosystems, community structure emerges as a result of the complex interaction between biotic and environmental variables. Sandy beaches connected to adjacent ecosystem like estuaries/creeks provide an opportunity to understand the role of the environment on the community. Kalbadevi beach along the central west coast of India, invaded by cr...

Although organic matter (OM) settling on the seafloor is generally rapidly recycled, a key ecological process, large scale burial events manifest itself in the marine sedimentary record as organic carbon (Corg)-rich layers. Presently, this prevails under certain oceanic settings such as the oxygen minimum zones (OMZ) where OM accumulates in underly...

Seven stations were sampled within the Mormugao harbour area for benthos and environmental variables from September 2003 to July 2004. A total of 71 polychaete taxa were identified from the area. Polychaete abundance, biomass and species number was highest during post monsoon, mainly due to new recruitment. Pre monsoon is the most stable period for...

Patterns of macrofaunal distribution were studied along the western Indian continental margin to distinguish the role of habitat heterogeneity in generating and maintaining community structure. A transect perpendicular to the coast at 14°N latitude was selected for seabed sampling. Eight stations were sampled in the depth range 34–2546 m and charac...

Natural disturbances along with human interference make the tropical estuaries amongst the most disturbed areas globally. In spite of this, information on the seasonal variability of macrofauna from tropical estuaries is few. Temporal variability of macrofaunal community from Mormugao Bay, Zuari estuary, on the west coast of India was examined from...

On 30 May 2006, a bulk carrier, MV Ocean Seraya ran aground along the Karwar coast spilling 650 tonnes of oil. Due to the rough SW monsoon, the spill spread to some beaches in south Goa. The aim of this communication is to study the immediate impact of oil spill on benthic ecology. It is also reviewed that the impact of frequent spills on the benth...

Harbours are heavily stressed coastal habitats characterised by high concentration of contaminant and low diversity of benthic community. The west coast of India harbours most of the major harbours compared to the east coast. Very few studies have compared the macrobenthic community between different Indian harbours. The present study was therefore...

The ecotoxicological effects of oil spill from the grounded vessel MV River Princess on the intertidal benthic organisms of Sinquerim-Candolim beach at Goa were investigated. An intertidal expanse of 1 km on either side of the grounded vessel was selected to evaluate the concentration of total petroleum hydrocarbon (TPH) in the sediment and its eff...

The variability of macrofaunal assemblage in the Mandovi–Zuari, Goa, India estuarine complex was studied during 2002-2003 and compared with earlier data of the same area. Sediment samples in duplicate were collected from 15 stations using a van Veen grab. A total of 68 taxa were identified with polychaetes dominating in terms of abundance and diver...

The intertidal area at Kalbadevi, Ratnagiri has been identified as one of the potential sites for placer minerals along the west coast of India. Considering the prospects of commercial mining, benthic sampling was conducted during February and May 2004 on the exposed intertidal beach to study the community structure and effect of physical disturban...