Atmospheric CO2 consumption by rock weathering over a five year period in a large non-perennial tropical river basin of southern India

Environmental Science and Pollution Research - Rivers engage in carbon cycle by transporting the dissolved products of weathering of rocks to the oceans, and this process is sensitive to the global...     

Synthetic organic chemicals (flame retardants and pesticides) with neurotoxic potential induced behavioral impairment on zebrafish (Danio rerio): a non-invasive approach for neurotoxicology

Environmental Science and Pollution Research - Behavior responses of organisms can be used as a non-invasive method for neurotoxicology studies since it directly links the nervous system’s...     

Impact of long-term exposure to mosquito coils: residual deposition and dissipation of D-trans-allethrin in a room

A D-trans-allethrin-based mosquito repellent coil formulation was used continuously in a room for 30 d. Two different experiments were conducted and the deposition of residues on different surfaces of the room was determined. Studies were conducted continuously for a period of 30 d in a fully closed room and in another room kept open for 14 h per day. The residues deposited on different surfaces, ceiling, side walls and floor, were measured. The results showed the accumulation of high concentrations of allethrin on all the surfaces of the room when the room was in a fully closed condition. Samples collected from the ceiling showed residues of D-trans-allethrin of 6.34-148.63 microg m(-2) during the 30 d study, the side walls 4.68-170.72 microg m(-2) and the floor 20.00-184.52 microg m(-2) Maximum residues were observed in 30 d samples collected from the ceiling and floor. The residual concentrations were nearly 10 times higher in samples collected from the closed room. Discontinuation of the use of the mosquito repellent after 30 d led to a gradual decrease in the concentrations of residues on all the surfaces. The influence of environmental parameters on the dissipation of residues was also studied.     

Mitigation of yield-scaled greenhouse gas emissions from irrigated rice through Azolla,Blue-green algae,and plant growth–promoting bacteria

Environmental Science and Pollution Research - Irrigated transplanted flooded rice is a major source of methane (CH4) emission. We carried out experiments for 2 years in irrigated flooded rice to...     

Recycling potential of MWCNTs/HDPE nanocomposite filament: 3D printing and mechanical characterization

Journal of Material Cycles and Waste Management - Fused filament fabrication (FFF) based additive manufacturing (AM) process is a widely used and emerging manufacturing process for...     

用Autospec-Ultima NT气相色谱-高分辨质谱分析二噁英及相关的持久性有机污染物

"二噁英"是指一类化学结构和生物特征均有某些相似之处的化合物.这些有毒化合物有几百种,可分为相关的三大类:氯代二苯并-对-二噁英(CDDs),氯代二苯并呋喃(CDFs)和某些多氯代联苯(PCBs).CDDs和CDFs并非与生具有,而是由于人类活动不注意而生成的.天然过程也会产生CDDs和CDFs.     

Investigations of an intense aerosol loading during 2007 cyclone SIDR – A study using satellite data and ground measurements over Indian region

Tropical cyclones are prominent weather systems characterized by high atmospheric pressure gradients and wind speeds. Intense tropical cyclones occur in India during the pre-monsoon (spring), early monsoon (early summer), or post-monsoon (fall) periods. Originating in both the Bay of Bengal (BoB) and the Arabian Sea (AS), these tropical cyclones often attain velocities of more than 100 km h^?1 and are notorious for causing intense rain and storm surge as they cross the Indian coast. In this study, we examine the changes in the aerosol properties associated with an intense tropical cyclone “SIDR”, that occurred during 11–16 November 2007 over BoB. This cyclone, accompanied with very strong surface winds reaching 223 km h^?1, caused extensive damage over Bangladesh. Ground-based measurements of Aerosol Optical Depth (AOD) in the neighboring urban environment of Hyderabad, India, showed significant variations due to changes in wind velocity and direction associated with the cyclone passage. The Terra-MODIS and AVHRR satellite images showed prevalence of dust particles mixed with emissions from anthropogenic sources and biomass-burning AS, while the aerosol loading over BoB was significantly lower. The positive values of Aerosol index (AI) obtained from the Ozone Monitoring Instrument (OMI) suggested the presence of an elevated aerosol layer over the West coast of India, AS and Thar Desert during and after the cyclone episode. Meteorological parameters from the MM5 mesoscale model were used to study the variations in winds associated with the cyclonic activity. Particulate matter loading over the region during the cyclone period increased by ～45% with an accompanying decrease in columnar aerosol optical depth. The variations in Angstrom parameters suggested coarse-mode particle loading due to dust aerosols as observed in satellite data.     

Predicted concentrations of biocides from antifouling paints in Visakhapatnam Harbour

The concentrations of biocides leached from antifouling coatings are monitored in most of the developed countries. However, in India and many other developing countries, there is very little data available on the concentrations of biocides in ports and harbours. The first step was to obtain the order of magnitude levels of concentrations of biocides in the marine environment of the Visakhapatnam Harbour, and the MAM-PEC (Marine Antifoulant Model to Predict Environmental Concentrations) model was used to predict these values. The Visakhapatnam Port lies on the eastern coast of India, roughly halfway between Chennai and Kolkata, and is the largest port in India. This port is a natural harbour; the long and narrow outlet to the open sea makes it a 'poorly flushed' harbour. Predicted concentrations of tributyltin (TBT), copper, dichlofluanid, seanine, irgarol, diuron, tolylfluanid, and zinc pyrithione were computed. The results of the computations indicate that the levels of these biocides are comparable to those in many western countries. This gives credence to the fact that persistence of TBT and some other biocides is a global problem that cannot be ignored.     

Application of GIS in the study of mass transport of pollutants by Adyar and Cooum Rivers in Chennai, Tamilnadu

Residential, industrial, commercial, institutional and recreational activities discharge degradable and non-degradable wastes that reach the coastal water through rivers and cause coastal pollution. In the present study, mass transport of pollutants by Adyar and Cooum Rivers to the coastal water as a result of land-based discharges was estimated during low tide. The lowest and the highest flow recorded in Adyar varied from 514.59 to 2,585.08×10⁶ litres/day. Similarly, the flow in Cooum River fluctuated between 266.45 and 709.34×10⁶ litres/day. The present study revealed that the Adyar River transported 53.89–454.11 t/d of suspended solids, 0.06–19.64 t/d of ammonia, 15.95–123.24 t/d of nitrate and 0.4–17.86 t/d of phosphate, 0.004–0.09 kg/d of cadmium, 0.15–1.29 kg/d of lead and 3.03–17.58 kg/d of zinc to the coastal water owing to its high discharge. Similarly, the Cooum River transported 11.87–120.06 t/d of suspended solids, 0.08–58.7 t/d of ammonia, 6.11–29.25 t/d of nitrate and 0.66–10.73 t/d of phosphate, 0.003–0.021 kg/d of cadmium, 0.02–0.44 kg/d of lead and 1.36–3.87 kg/d of zinc. A higher concentration of suspended solids was noticed in post monsoon and summer months. An increase in the mass transport of ammonia, nitrate, phosphate in summer months (April and May) and an increase in the mass transport of cadmium, lead and zinc were observed in monsoon months (October–December) in both the rivers. Thus mass transport of pollutants study reveal that Cooum and Adyar Rivers in Chennai contribute to coastal pollution by transporting inorganic and trace metals significantly through land drainage.