Ecophysiological status of copepods in the oxygen minimum zone of Eastern Arabian Sea.

Eutrophication of marine ecosystems is a global problem, particularly in a changing climate and the spreading of Oxygen Minimum Zones (OMZs). The eastern Arabian Sea has both seasonal and permanent/perennial OMZs, but our understanding of the fauna there is extremely poor. So, this study investigated the composition and physiological status (alive or dead) of zooplankton (copepods) in the two OMZs.

Impact of river discharge and suspended sediments on the nearshore benthic environment along the Indian southwest coast.

River discharge into the sea and its implications on the environmental setting and fauna in the nearshore represent the intricate interactions among the atmosphere, hydrosphere, lithosphere, and biosphere. This study, based on in-situ and satellite data, presents how spatially varying river discharge laden with suspended sediments structure the hydrography and the nearshore benthic environment over a 590 km southwest (Kerala) coast of India. The 41 rivers that discharge along the Kerala coast are monsoon-driven; they are small but swift and cumulatively supply huge amounts of freshwater and suspended sediments into the Southeastern Arabian Sea (SEAS) during the Southwest Monsoon (SWM) when around 70 % (1925 mm) of the yearly rainfall occurs.

Copepoda community imprints the continuity of the oceanic and shelf oxygen minimum zones along the west coast of India.

The largest continental shelf Oxygen Minimum Zone (OMZ) in the world is formed along the Indian western shelf in the eastern Arabian Sea during the Southwest Monsoon [(SWM); June-September], which is a natural pollution event associated with the coastal upwelling. This study examines the composition, abundance, and distribution of copepods during the Northeast Monsoon [(NEM); November to February] and SWM in 50 m depth zones along the Indian western shelf in the eastern Arabian Sea. The NEM was characterised by warm, stratified, and low-salinity waters in the southeast Arabian Sea and cold, high-salinity, and well-mixed waters in the northeastern Arabian Sea.

Environmental and human facets of the waterweed proliferation in a Vast Tropical Ramsar Wetland-Vembanad Lake System.

The Vembanad Lake and its associated low-lying areas and network of canals (hereafter VBL) form the major part of India's second-largest Ramsar wetland (1512 km) located in Kerala State along India's southwest coast. The extensive VBL has a large fishery, inland waterways, and popular tourist attractions that support the livelihoods of thousands of people. Over the last several decades, the proliferation of water weeds in the VBL has alarmingly increased, causing many adverse ecological and socioeconomic effects.

Winter phytoplankton size classes in the Northeastern Arabian Sea based on in-situ and remote sensing methods.

Phytoplankton size classes (PSCs) are important in marine ecosystems because they organise the food chain and trophic pathways, which determine the overall biological environment. Based on three FORV Sagar Sampada cruises, the current study provides changes in PSCs in the Northeastern Arabian Sea (NEAS; north of 18 N) during different phases of the Northeast Monsoon [NEM (November-February)]. During all three phases of NEM such as early (November), peak (December), and late (February), in-situ chlorophyll-a fractionation data revealed that nanoplankton (2-20 μm) predominated, followed by microplankton (>20 μm) and picoplankton (0.

Microplastics in copepods reflects the manmade flow restrictions in the Kochi backwaters, along the southwest coast of India.

This baseline study on microplastics (MPs) in calanoid copepods in the Kochi backwaters (KBW), India's largest estuary system on the west coast, focuses on (a) the spatiotemporal variations of MPs with the seasonal hydrography setting, and (b) how man-made flow restrictions of a large saltwater barrage contribute to MPs in copepods and their potential to transfer to higher trophic levels. This study found that MPs in copepods in the KBW ranged from av. 0.