Showing papers by "Punarbasu Chaudhuri published in 2014"

Plant canopies: bio-monitor and trap for re-suspended dust particulates contaminated with heavy metals

Abstract: Urban and peri-urban vegetation is being considered for air pollution abatement. Appropriate plants with efficiency to adsorb and absorb air-pollutants are the prerequisite for green space development. The contributions of surface morphology towards plant’s ability to function as dust particulate adsorber and distribution of trace elements over the leaves are investigated in the present study. Dust interception efficiency was estimated for two roadside plant species named Ficus benghalensis, and Polyalthia longifolia. Leaves of both the plants are capable of capturing dust in the range of 0.12 mg/cm2 to 1.89 mg/cm2 on either of the leaf surfaces. However, variation in dust capturing capacity between the plants was observed. Leaf surface characters such as roughness, length, frequency of trichomes and frequency of stomata played a significant role in capturing re-suspended dust. Frequency (2 to 4 per 0.0004 cm2) and length (152.5 to 92.1 cm) of trichome showed negative co-relation trend, where as frequency and size of stomata showed positive co-relation trend. Elemental analysis by Scanning Electron Microscope attached with Energy Dispersive X-Ray Spectrometer (SEMEDS) indicated the presence of elements such as Sodium (Na), Magnesium (Mg), Aluminium (Al), Silicon (Si), Chlorine (Cl), Pottasium (K), Calcium (Ca), Iron (Fe), Zinc (Zn) and Arsenic (As). The results support the fact that plant canopies can be used for mitigation and bio-monitoring of air pollution as well.

Assessment of Morphological Damages of Leaves of Selected Plant Species due to Vehicular Air Pollution, Kolkata, India

Abstract: The present study deals to know morphological damages of leaves of four selected plant species near roadside due to vehicular air pollution in Kolkata, India. The selected plant species are Ficus bengalensis, Ficus religiosa, Alstonia scholaris and Neolamarckia cadamba as these are very common as avenue trees. The study area was selected as per Low vehicular load (LVL) as control area, moderate vehicular load (MVL) area, high vehicular load (HVL) area and heavy vehicular load (HeVL) These three sampling stations were selected on the basis of moderate, high and heavy traffic density and continuous vehicular movement as per visualization. The control area was considered as time dependent vehicular movement due to less traffic density. The morphological damages with special reference to length (L), breadth (B) and L/B ratio and visible injuries in leaves. The visible injuries such as pigmentation, chlorosis, necrosis and burning of leaves of four selected species is documented. There was an increasing and decreasing tends in all four plant species at all three vehicular emission exposed sites (MVL, HVL and HeVL) compared to control site (LVL). In all experimental sites such as MVL, HVL and HeVL, the extra growth and reduction pattern significantly (P < 0.001, 0.01 or 0.05) observed when compared to control site (LVL) for L, B and L/B ratio. The visible injuries (in %) of leaves were also observed in increasing trends. This study is a preliminary assessment of tolerant species that already have been used in greenbelt development to protect air pollutants as well as biological monitoring to know exact load of automobile air pollution but further researches are needed in relation to biochemical and genetic damage study. It was observed that out of four selected species Ficus bengalensis, Alstonia scholaris and Neolamarckia cadamba are more tolerant species and Ficus religiosa is a less tolerant species because of these may have fighting abilities by waxy coatings, accumulation and degradation abilities to vehicular air pollution at all exposed area when compared to control area.

Potentiality assessment of fish scale biodegradation using mangrove fungi isolated from Indian Sundarban

Abstract: The mangrove fungi, morphologically and physiologically adapted in a different habitat, were isolated from mangrove habitat of Jharkhali, Sundarban, India. The physico-chemical properties like temperature, pH, soil colour, moisture content, carbon and nitrogen content of soil determines the load of microbial population. The soil sample was serially diluted and plated on potato dextrose agar plate with ampicillin to obtain fungal isolates. Total of six isolates were characterized microscopically by lacto phenol cotton blue staining. Two of them were identified as Aspergillus niger and Penicillium sp. and are subjected to biodegradation of fish scale, the major waste of fish processing industries. Aspergillus niger was found to be the best for degradation of fish scale powder by producing zone of clearance. Moreover, media without fish scale didn’t show any zone of clearance indicates the mangrove fungi are capable of degrading the fish scale component.

Nuclear Microscopy for Air-Pollutant Characterization and Its Advantages over Traditional Techniques

Abstract: In the present study we establish the use of the proton induced X-ray emission (PIXE) technique coupled with Rutherford backscattering as a sensitive technique for air-pollution monitoring. Several elements such as Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, and As were detected in the ppm level of concentration. Comparisons show the advantages of micro-PIXE over scanning microscope-based energy-dispersive X-ray spectrometry (SEM-EDX) and energy-dispersive X-ray fluorescence spectrometry (EDXRF).