Arsenic is regarded as one of the potential toxic elements contaminating the ground water, and the toxicity level of Arsenic is reportedly higher in ground waters of Asiatic countries. Among all the South Asian countries, Bangladesh and West Bengal in India are worst hit by Arsenic contamination in their ground waters. Phytohormones have a useful role in counteracting the effect of toxic metals and metalloids such as Arsenic, Lead and Chromium. Similarly, macro-elements like Phosphorous, Sulfur and organic acids like malate, citrate and pyruvate have also been found to have ameliorative role towards plants grown using contaminated water. In the first paper, “Reduction of Arsenate Induced Oxidative Stress in Mungbean Seedlings by Phosphate Salts and Phytohormones”, by Arpita Swarnakar and Subhendu Mukherji, the effect of Sodium arsenate on the growth and activity of few oxidizing enzymes of mungbean seedlings was investigated and the observations reveal that the decrease in seedling length, fresh weight and dry weight of the mungbean seedlings is proportional to the concentration of arsenate.

Deterioration in water quality due to nonpoint sources of pollution is one of the major challenges in water quality management faced by developing countries like India. Surface runoff, especially during the ‘first flush’ conditions is an important source of nonpoint source pollution. In the second paper, “Assessment of Pollution Potential of First Flush Runoff from an Urban Roadway”, by Shivani Sood, Vibhor Sood and Siby John, an attempt was made to characterize the road runoff quality and assess the pollution potential of the urban road runoff of different zones of Chandigarh. The results obtained revealed that TSS, COD and Concentrations of heavy metals like Cr6+, Fe, Zn, Pb, Ni were exceeding the Indian National Surface Water Discharge Standards.

Composting is one of the natural methods of waste degradation in which microbial decomposition of organic matter occurs under aerobic conditions. The process involves the oxidation of Carbon in hydrocarbons from C0 to C4+ state to produce oxidation products such as CO2, H2O(l) and a considerable amount of heat. Minerals and organic matter of the hydrocarbons get converted into potentially reusable soil amendments. In the third paper, “Composting of Food and Vegetable Waste”, by Kunwar D Yadav, N J Mistry, Daxesh Pandya and Bhupesh Ganvit , a study was conducted to find out the degradation aspects of food and vegetable wastes.

There has been a worldwide concern for sustainable development especially after the 1992s Rio’s UN Conference on Environment and Development. Rapid encroachment of urban development on valuable agricultural land will have a great influence on the achievement of sustainable development . A sustainable land development model is developed using GIS in an attempt to control urban sprawl under rapid rural urbanization. In the fourth paper, “Development of Land Suitability Model (LSM) for Irrigation Management Using Remote Sensing, GIS, GPS and Field Studies: A Case Study of a Part of Nagarjunasagar Command Area, Prakasam District, Andhra Pradesh, India”, by K Santosh Kumar and M Anji Reddy, a study was carried out with a set of objectives to examine and analyze the spatial information related to the present practices of irrigation, generate Geographic Information System (GIS) and Mandal Information System (MIS) digital database, spatial database creation, and to develop soil and water quality assessment for the study area.

Mangrove ecosystems which act as buffers between land and sea are important as they protect the land from the effect of violent sea during floods as well as prevent soil erosion by trapping and depositing the sediments brought by tides. The phytogeographical distribution of these mangroves within the Indian subcontinent is along the western and eastern coasts and in parts of isolated islands of Andaman and Nicobar. Remote Sensing (RS) in conjunction with Geographical Information System (GIS), and geospatial tools, proved beneficial in providing a detailed scenario on the past and present land use and land cover patterns of a given area.

In the fifth paper, “Analysis of Spatial and Temporal Changes in Mangroves Along Thane Creek of Mumbai (India) Using Geospatial Tools”, by P Ram Chandra Prasad, Chiranjibi Pattanaik, S Narendra Prasad and C B S Dutt, a study was carried out to analyze the spatial and temporal changes which occurred along the parts of Thane creek of Mumbai using different satellite imagery. The study revealed an increase of mangrove areas along the coastline from 1992 to 2001 and a decrease from 2001 to 2005.

Bioreactors are modeled and fabricated according to the biochemical reactions proposed to be carried out inside it. Upflow Aerobic Fixed Bed Bioreactor (UAFBBR) is a typical version of airlift reactor which contains a column filled with various types of solid media for the treatment of carbonaceous organic matter in the wastewater. One of the advantages of this version is the attainment of very long mean residence time at moderately low Hydraulic Retention Time (HRT) which is essential for an efficient treatment. In the sixth paper, “Pall Rings Media Performance Studies on Upflow Aerobic Fixed Bed Bioreactor for the Treatment of Dairy Wastewater”, by Madan Mohan Reddy K, Sanjeeva Rayudu E and Srimurali M, studies were conducted to assess the influence of HRT on performance of UAFBBR for the treatment of dairy wastewater. The waste treatment performance indicates that the UAFBBR packed with pall rings media demonstrated the highest COD and BOD removal efficiency.

Air pollution is a major cause of environmental health problems with devastating effects all over the World. In recent years, new air sampling techniques have been developed for the assessment of air pollutants. In the seventh paper, “Quantification of Chlorine and Hydrogen Chloride in Air using Chemically-Treated Filter”, by A H Abba, M Rashid, C M Hasfalina, Z Z Noor and T B Whei, a simplified technique based on US EPA Test Method 26/26A was developed to quantify the concentration of Chlorine and Hydrogen chloride in indoor air.

The collection of acid gases was compared by liquid absorption between impingers and the chemically treated-filter. A rise in the sea level has many implications for natural environment and accelerates coastal erosion. It also impacts groundwater quality of the coastal habitat. In South-East Asia, these problems are exacerbated as the ground level is also sinking at the same time as the sea level is rising. This, combined with changes in rainfall patterns and increased demand for water, increases the risk to coastal aquifers of saline intrusion. In the last paper, “Saline Intrusion Modeling of Sea Water Level Rise Impact on a Natural River in Miri, Sarawak”, Hii Ching Poon, Fredrik Josep Putuhena and Salim Said, have reported a salinity modelling exercise.

-- G S Brahma
Consulting Editor