Biomarker responses in the Coilia dussumieri exposed to petroleum hydrocarbons contamination in urbanized estuaries along the west coast of India.

The estuaries of Maharashtra are under continuous pressure due to uncontrolled dumping of persistent toxic organic pollutants into these regions and their impact on the marine environment. In this study, total petroleum hydrocarbons (TPHs) in water, sediments, fish, and biomarker responses in the Coilia dussumieri exposed to TPHs were determined in seven urbanized tropical estuaries along the west coast of India during the winter and summer. The results of the cluster analysis highlighted that the concentration of TPHs in the water, sediment, and fish in the study area was spatially varied, with the highest concentration in the northern area of Maharashtra (NM) estuaries than in the southern region of Maharashtra (SM) estuaries during both seasons.

Ecobiology and distribution of Streptomyces species from distinctive metal polluted sediment of tropical estuary, Northwest coast of India.

The present study aims to isolate diverse actinomycetes communities from the estuarine sediments of Patalganga located at Northwest coast of India. Total 40 actinomycetes were isolated from 24 sediment samples by dilution plating on six different isolation media. Among them, morphologically 18 distinct selected isolates of actinomycetes were verified by 16S rRNA gene sequencing and identified as Streptomyces spp.

Phytoplankton assemblage and chlorophyll a along the salinity gradient in a hypoxic eutrophic tropical estuary-Ulhas Estuary, West Coast of India.

Phytoplankton assemblage and chlorophyll a along the salinity gradient and oxygen zonation were studied in Ulhas Estuary. Oxic condition exist in euhaline region of the estuary that receives oxygenated coastal waters, while, poly-meso-oligohaline region is hypoxic due to the accumulation of voluminous amount of pollutants from industrial effluents, domestic/sewage and agricultural discharges. Additionally, anthropogenically generated nutrients enhanced phytoplankton biomass (chlorophyll a) and their senescence also led to hypoxia.

Effects of sedimentary heavy metals on meiobenthic community in tropical estuaries along eastern Arabian Sea.

The central west coast of India comprises the 720 km long coastline of Maharashtra state and houses widespread industrial zones along the eastern Arabian Sea. Sediments from seven industrial-dominated estuaries along the central west coast were studied for metal enrichment and benthic assemblages to determine sediment quality status and ecological effects in these areas. The suit of geochemical indices highlighted the contamination of sediment in the estuaries concerning heavy metals.

Multivariate assessment of outflow water quality in highly urbanized creek system: implication of natural and anthropogenic processes.

Nutrient source and transport study in tropical creeks adjacent to megacities are sparse on a regional and global scale. High-frequency chemical data collected during 2017-2018 in the Thane creek system, the largest micro-tidal urbanized creek in Asia, were analysed to assess the chemical water quality, with its linkage to different hydrological stages (southwest monsoon, post- and pre-monsoon) and ongoing anthropogenic activities. Cluster analysis indicates typical zonation between creek outflow and nearshore waters with distinctive physicochemical properties.

Inter-annual variability of phytoplankton assemblage and Tetraspora gelatinosa bloom from anthropogenically affected harbour, Veraval, India.

Veraval, one of Asia's largest fishing harbours, situated on the south-west coast of Gujarat, India, has transformed into an industrial hub dominated by fish processing units, rayon manufacturing industry, and transportation facilities. The study investigated the high abundance of Tetraspora gelatinosa along with the augmented level of ammonia in the harbour. The high concentration of ammonia was associated with the accumulation of sewage, industrial, and fishery wastes in the harbour.

Factors controlling organic matter composition and trophic state in seven tropical estuaries along the west coast of India.

To understand the organic matter (OM) sources and trophic states, spatial and seasonal (post-monsoon and pre-monsoon) variation in sedimentary OM compositions was investigated in seven tropical estuaries of the state of Maharashtra along the central west coast of India. Based on the result of cluster analysis, estuaries were segregated into two distinct groups: Northern Maharashtra and Southern Maharashtra owing to dissimilarity in OM characteristics potentially constrained by geomorphology and catchment properties. Enrichment of C and major biochemical compounds (lipids, carbohydrates and proteins) in the middle zone of most estuaries highlighted towards the addition of allochthonous OM.

Behaviour of trace metals in the anoxic environment of Veraval harbour, India.

The purpose of the present study is to investigate the behaviour of trace metals in anoxic environment. Water column of the harbour was found to be anoxic (DO <0.2mgl) with high concentration of NH-N (av.

Role of heavy metals in structuring the microbial community associated with particulate matter in a tropical estuary.

Particulate matter (PM), which are chemically and biochemically complicated particles, accommodate a plethora of microorganisms. In the present study, we report the influence of heavy metal pollution on the abundance and community structure of archaea and bacteria associated with PM samples collected from polluted and non-polluted regions of Cochin Estuary (CE), Southwest coast of India. We observed an accumulation of heavy metals in PM collected from CE, and their concentrations were in the order Fe > Zn > Mn > Cr > Pb > Cu > Cd > Co > Ni.

Seasonal distribution of phytoplankton and its association with physico-chemical parameters in coastal waters of Malvan, west coast of India.

Malvan coast is one of the Marine Protected Area (MPA) of Maharashtra because of its rich coral reef and biodiversity. The study investigated on phytoplankton assemblage and their diversity with respect to physico-chemical parameters covering protected and unprotected area of Malvan coast. Physico-chemical parameters such as salinity, nitrite, nitrate, and ammonia did not display seasonality due to inadequate fresh water influx and allochthonous nutrient input.

A Preliminary Estimate of Total Petroleum Hydrocarbons in Water and Some Commercially Important Fish Species in the Amba Estuary, West Coast of India.

Amba Estuary, which receives effluent from several industries including a petrochemical complex, opens to the southern limits of the Mumbai Harbor. The study was conducted to find out the level of Total Petroleum Hydrocarbons (TPHs) in water and their bioconcentration in ten commercially important fishes from Amba Estuary during different months. In water high concentration of TPHs (39.

Effect of heavy metals on the carbon and nitrogen ratio in Avicennia marina from polluted and unpolluted regions.

The accumulation of heavy metals and its impact on the C/N ratio of Avicennia marina of the Patalganga and Amba estuaries were studied. Vadinar was selected as a relatively uncontaminated location for comparison. Cd was accumulated in leaves of the Patalganga and Amba estuarine mangroves; however, at Vadinar it was accumulated and arrested only in roots and stems.

Bioaccumulation of heavy metals in commercially important marine fishes from Mumbai Harbor, India.

Seventeen commercially important marine fish species were caught in Mumbai Harbor using a trawl net and evaluated using Atomic Absorption Spectroscopy and ICP-OES. It was found that certain species of fish contained lower levels of all metals tested. J.

Diagenesis and bioavailability of mercury in the contaminated sediments of Ulhas Estuary, India.

Sequential extraction of Hg was performed in a core collected from intertidal area in Ulhas Estuary in order to characterize the downward distribution and diagenetic behavior of Hg in a polluted estuary. Concentration of total Hg ranged between 0.46 and 6.

Mercury in sediments of Ulhas estuary.

Hg levels in water, suspended particulate matter and sediment of the Ulhas estuary are under considerable environmental stress due to the indiscriminate release of effluents from a variety of industries including chlor-alkali plants. Concentration ranges of dissolved (0.04-0.