Environmental DNA reveals aquatic biodiversity of an urban backwater area, southeast coast of India.

Strong conservation management needs comprehensive data on biodiversity. Rapid methods that document aquatic biodiversity or assess the health condition of an ecosystem remain scarce. Herein, we have performed a metagenomics study on environmental DNA (eDNA) collected from an urban backwater area - Muttukadu, located in the southeast coast of India.

Geochemical fractionation study in combination with equilibrium based chemical speciation modelling of Cd in finer sediments provide a better description of Cd bioavailability in tropical estuarine systems.

Geochemical fractionation study of cadmium (Cd) in combination with equilibrium based chemical speciation modelling (visual MINTEQ) in finer sediment samples (silt and clay portion), provided a better description of Cd bioavailability for sessile organisms (like oysters) in the Zuari estuary, west coast of India. A substantial fraction of total Cd in the finer sediment samples was present as water soluble, exchangeable and carbonate/bicarbonate forms and showed a strong positive relationship with Cd-bioaccumulation in oysters (Magallana sp.) from the study area.

Operationally defined mercury (Hg) species can delineate Hg bioaccumulation in mangrove sediment systems: A case study.

This study investigated the linkage between mercury (Hg) speciation in the surficial sediments from a mangrove ecosystem of the Zuari Estuary, west coast of India, with Hg bioaccumulation in gastropods collected from the same area. Multiple operationally defined protocols and methods were used for determination of Hg speciation study in the mangrove sediments. Moderately low concentrations of Hg were observed in the sediments, ranging from 37.

Correction: Reinvestigating an enigmatic Late Cretaceous monocot: morphology, taxonomy, and biogeography of .

[This corrects the article DOI: 10.7717/peerj.4580.

Effect of pH on transport and transformation of Cu-sediment complexes in mangrove systems.

Impact of pH variation of overlying water column on transport and transformation of Cu-sediment complexes in the bottom mangrove sediments was investigated by using different metal extraction studies. The total Cu concentration in the studied sediments varied from ~64 ± 1 to 78 ± 2 mg·kg. The sequential extraction study showed that a major part of the sedimentary Cu (85-90% of the total sedimentary Cu) was present within the structure of the sediments with minimum mobility and bioavailability.

Reinvestigating an enigmatic Late Cretaceous monocot: morphology, taxonomy, and biogeography of .

Angiosperm-dominated floras of the Late Cretaceous are essential for understanding the evolutionary, ecological, and geographic radiation of flowering plants. The Late Cretaceous-early Paleogene Deccan Intertrappean Beds of India contain angiosperm-dominated plant fossil assemblages known from multiple localities in central India. Numerous monocots have been documented from these assemblages, providing a window into an important but poorly understood time in their diversification.

Testing the efficiency of temperate benthic biotic indices in assessing the ecological status of a tropical ecosystem.

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 univariate indices, ecological strategies, indicator species and multimetric indices. AMBI and multimetric indices performed satisfactorily in evaluating the ecological status.

Linkage between speciation of Cd in mangrove sediment and its bioaccumulation in total soft tissue of oyster from the west coast of India.

This study established a mechanistic linkage between Cd speciation and bioavailability in mangrove system from the west coast of India. High bioaccumulation of Cd was found in the oyster (Crassostrea sp.) even at low Cd loading in the bottom sediment.

Mercury profiles in sediment from the marginal high of Arabian Sea: an indicator of increasing anthropogenic Hg input.

Total Hg distributions and its speciation were determined in two sediment cores collected from the western continental marginal high of India. Total Hg content in the sediment was found to gradually increase (by approximately two times) towards the surface in both the cores. It was found that Hg was preferentially bound to sulfide under anoxic condition.

Relationship between the lability of sediment-bound Cd and its bioaccumulation in edible oyster.

A linkage between Cd speciation in sediments and its bioaccumulation in edible oyster (Crassostrea sp.) from a tropical estuarine system was established. Bioaccumulation of Cd in edible oyster increased with the increasing lability and dissociation rate constants of Cd-sediment complexes in the bottom sediments.

Geochemical partitioning of Cu and Ni in mangrove sediments: relationships with their bioavailability.

Sequential extraction study was performed to determine the concentrations of non-residual metal-complexes in the mangrove sediments from the Divar Island, (west coast of India). Accumulation of metal in the mangrove roots (from the same location) was determined and used as an indicator of bioavailability of metal. An attempt was made to establish a mechanistic linkage between the non-residual metal complexes and their bioavailability in the mangrove system.

Reduction of mercury (II) by humic substances--influence of pH, salinity of aquatic system.

This study demonstrates that under abiotic dark conditions in aquatic system, humic substances are not only capable of converting Hg(II) to Hg(0) but also able to bind Hg(II) ion. The degree of Hg(II) reduction is significantly influenced by the ratio of -COOH/-OH groups and the sulfur content in the HS, revealing a strong competition between complexation and reduction of Hg(II). This study suggests that abiotic and dark Hg(II) reduction depends on the pH and salinity of aqueous medium.

Kinetic speciation and bioavailability of copper and nickel in mangrove sediments.

An attempt was made to establish a mechanistic linkage between chemical speciation of copper and nickel, and their bioavailability in mangrove ecosystem. Kinetic speciation study was performed to determine the concentrations of labile metal-complexes and their dissociation rate constants in mangrove sediments. Concentrations of copper and nickel in the mangrove roots were used as indicators of their bioavailability.

Impedance spectroscopic characterization of Sm2O3 containing lithium borate glasses.

27.5 Li2O-(72.5-X) B2O3-X Sm2O3 (X=0.

Mercury speciation in coastal sediments from the central east coast of India by modified BCR method.

This is the first study to describe distribution and speciation of Hg in coastal sediments from the central east coast of India. The concentrations of Hg in the studied sediments were found to be much lower than the Hg concentration recommended in coastal sediments by the United State Environmental Protection Agency and the Canadian Council of Ministers of the Environment for the protection of aquatic life. This study suggests that the interactions between Hg and coastal sediments are influenced by particle size (sand, silt and clay) of the sediments and the total organic carbon (TOC) content in the sediments.

Investigation of Volatile Mono-Aromatic Hydrocarbons and 1,3-Butadiene in an Urban Metropolis, India.

In urban areas, benzene, toluene, ethyl benzene and xylenes (BTEX) constitute up to 60% of nonmethane VOCs. The present work was conducted to determine the ambient volatile 1, 3-butadiene and mono-aromatic hydrocarbons in an urban metropolis of Nagpur, India. Continuous sampling was carried out at high density traffic junctions, major petrol filling stations along with some residential areas during March to May, 2011.

Accessible engineering drawings for visually impaired machine operators.

An engineering drawing provides manufacturing information to a machine operator. An operator plans and executes machining operations based on this information. A visually impaired (VI) operator does not have direct access to the drawings.

Changes in metal contamination levels in estuarine sediments around India--an assessment.

This review is the first attempt to comprehend the changes in metal contamination levels in surface estuarine sediments with changing time around India. Contamination factor, geoaccumulation index, pollution load index, effects range low and effects range median analysis were used to evaluate the quality of the estuarine sediments (by using the available literature data). This study suggests that estuarine sediments from the east coast of India were comparatively less contaminated by metals than the west coast.

Impact of paper mill wastewater on soil properties and crop yield through lysimeter studies.

Paper and pulp industries produce large quantities of wastewater which can have adverse effects on the receiving water systems. In the present study lysimeters were used and filled with different soils replicating natural soil horizons and provided with a leachate collection system. The physico-chemical characteristics of the soil in each lysimeter and the quality of wastewater before leaching were assessed.

Assessment of poly aromatic hydrocarbon (PAH) dispersion in the near shore environment of Mumbai, India after a large scale oil spill.

This study was carried out to generate data pertaining to spatial distribution of PAHs immediately after an oil spill event in a near shore environment. The physico-chemical characteristics of the sea water after the oil spill event indicated pH variation between 7.69 and 8.

Statistical assessment of groundwater resources in Washim district (India).

Groundwater quality of Washim district of Maharashtra (India) was assessed using quality parameters and water quality index (WQI). In this study, the WQI was analyzed by using pH, turbidity, temperature, nitrates, total phosphates, dissolved oxygen, biochemical oxygen demand, total solids, total coliforms and faecal coliforms, respectively for residential and commercial uses. All the parameters were analyzed both in pre-monsoon and post-monsoon seasons to assess the groundwater quality and seasonal variations.

Characterization of chromophoric dissolved organic matter (CDOM) in rainwater using fluorescence spectrophotometry.

The fluorescence excitation-emission matrix of Chromophoric dissolved organic matter (CDOM) samples from rainwater collected at Rameswaram, Tamilnadu, India are analysed. Total five peaks were observed for humic/marine and protein likes substances respectively. The peak A and C intensities varies form 1.

PAH composition of Water Based Drilling Mud and drill cuttings in the offshore region, east coast of India.

As a consequence of offshore drilling, used Water Based Drilling Muds (WBMs) are typically disposed off, by discharging into the sea; such a disposal does not fully eliminate the environmental hazards. Hence, in this study, 2, 3, 4 and 5 ringed polycyclic aromatic hydrocarbons (PAHs i.e.