Desertification around Hirakud reservoir

Summary A comparative study of Survey of India topo-maps of 1929 and land satellite imageries in False Colour Combination (FCC) of 1975 indicates a loss of 43% and 46% of the reserved forest around Sambalpur and Jharsuguda respectively, besides other forest types in a radius of twenty miles. Deforestation is found to be an accelerating process where the rate of loss is estimated to be more during 1970–75 and 1960–70 in comparison to 1950–60 from a semilogarithmic trend curve between 1929 and 1975. This curve also fits to a hypothesis that the rate of deforestation is faster after 1950 (after developmental plan periods came into force). An analysis of the climatic data indicates a decrease in rainfall and number of rainy days, and morning relative humidity. The mean minimum and maximum temperature, evening relative humidity and atmospheric pressure show increasing trends. Relationships between forest loss and climatic parameters are significant for morning relative humidity, rainy days, maximum temperature and atmospheric pressure. Considering the loss of storage capacity of the Hirakud reservoir due to severe deforestation in the catchment area, suggestions are given for natural forest preservation. Arttabandhu Mishra graduated in Science (Zoology Honours) and Education from Utkal University; postgraduated from Berhampur University, India. At present he is a Lecturer in School of Life Sciences, Sambalpur University and Secretary of Orissa Environmental Consciousness Society. His fields of interests are Productivity and Energetics of Forest Ecosystems, Environmental Education and Community Education. He has published seven papers on the above fields and a number bf popular articles. He tries to use folk literature as media to carry scientific messages. Madhab C. Dash, obtained his B.Sc. (Hens), M.Sc. from Utkal University, India and Ph.D. from University of Calgary, Canada. At present he is Professor and Head, School of Life Sciences, Sambalpur University, a fellow of the Zoological Society of India, the National Institute of Ecology and the National Academy of Sciences, India. His major areas of research and writing are on the functional role of soil organisms in the decomposer subsystem of ecosystems, He has published seventy-five papers on taxonomy, biology, population ecology, metabolic functions, energy flow modelling, role in soft fertility and waste conditioning ability of Oligochaetes, nematodes, protozoa and soil microorganisms. Professor Dash has contributed specialised chapters in major treaties published by Cambridge University Press, UK; John Wiley and Sons, USA; and Academic Press, New York, USA.     

Understanding the dynamics of heavy metals in a freshwater ecosystem through their toxicity and bioavailability assay

The current study investigates on correlating the heavy metal contamination, its distribution, and the human health risk associated with all three components of an aquatic ecosystem. For this purpose, water, sediment, and fish samples (three species, notably Notopterus notopterus, Clarias batrachus, and Channa striata) from Deepor Beel were considered, and their heavy metal contamination and distribution were determined. The corresponding health risks were then evaluated for six different heavy metals; Cr, Cd, Fe, Mn, Cu, and Pb. Pb and Mn were found to significantly impact the non-carcinogenic human health risks for the water column. Simultaneously, Cd was considered to possess the highest potential for both carcinogenic and non-carcinogenic health effects in the sediment column. Cd also played a critical role in the fish samples' bioaccumulation factor, with the liver showing the maximum bioaccumulation potential. Furthermore, children were found to have considerably higher effects (both carcinogenic and non-carcinogenic) than adults. Finally, the sediment column was found to substantially contribute to the bioaccumulation factor in the fish biota, compared to the water column. The results of this investigation will thus prove consequential in designing, monitoring and restoring aquatic ecosystems.

     

Effect of photo-biodegradation and biodegradation on the biogeochemical cycling of dissolved organic matter across diverse surface water bodies

The objective of this research was to quantify the temporal variation of dissolved organic matter(DOM) in five distinct waterbodies in watersheds with diverse types of land use and land cover in the presence and absence of sunlight. The water bodies were an agricultural pond, a lake in a forested watershed, a man-made reservoir, an estuary, and a bay. Two sets of samples were prepared by dispensing unfiltered samples into filtered samples in 1:10 ratio(V/V). The first set was exposed to sunlight(10 hr per day for 30 days) for examining the combined effect of photo-biodegradation, while the second set was stored in dark for examining biodegradation alone. Spectroscopic measurements in tandem with multivariate statistics were used to interpret DOM lability and composition. The results suggest that the agricultural pond behaved differently compared to other study locations during degradation experiments due to the presence of higher amount of microbial humic-like and protein-like components derived from microbial/anthropogenic sources. For all samples, a larger decrease in dissolved organic carbon(DOC) concentration(10.12% ±9.81% for photo-biodegradation and 6.65% ± 2.83% for biodegradation) and rapid transformation of DOM components(i.e., terrestrial humic-like components into microbial humic and protein-like components) were observed during photo-biodegradation experiments.Results suggest that sunlight facilitated DOM biodegradation, resulting in simpler recalcitrant molecules regardless of original composition. Overall, it was found that combined effects of light and bacteria are more efficient than bacterial effects alone in remineralizing and altering DOM, which highlights the crucial importance of sunlight in transforming aquatic DOM.     

Performance evaluation of Nahar oil–diesel blends in a single cylinder direct injection diesel engine

This study attempts to use plentiful available high oil content (67% of Nahar seed kernel) non-edible feedstock as a source for powering diesel engine. Various performance and emission characteristics of prepared Nahar oil–diesel blends (5%, 10%, 20%, 30%, and 40%) are analyzed in a single cylinder direct injection diesel engine at different load spectrum, in order to judge the optimum blend, which can be efficiently used in a diesel engine. 10% blending of Nahar oil with diesel fuel has shown a reduction in hydrocarbon and carbon monoxide emission by 8.64% and 8.34%, respectively. With the increase in blend concentration, the nitrogen oxide emission decreased considerably and smoke emission increased slightly. Further pressure crank angle and heat release rate analysis of 10% blending of Nahar oil with diesel confirms its smooth combustion inside the engine combustion chamber.     

Understanding the factors that influence household use of clean energy in the Similipal Tiger Reserve,India

Biotic pressure in and around protected areas (PA) is the primary cause of biodiversity loss in many developing countries across the globe. The pressure comes partly from biomass energy dependency in the form of heavy extraction of fuelwood from the forests. Although biomass fuels provide easily accessible and affordable sources of domestic energy to the rural masses, their combustion results in environmental and health‐related hazards. The objectives of this paper are to assess the patterns of household energy use in a subsistence forest economy and analyze the factors that influence their energy use choice for cooking and lighting. The paper uses primary data collected randomly from 244 households located in and around the Similipal Tiger Reserve (STR), situated in the eastern Indian state of Odisha. Age of the household head, number of days in wage employment, number of adult males and females in a household, education of the household head and landholding size are found to be the major variables that determine household fuelwood collection sources inside the reserve. Considering household structure as an income indicator, the analysis clearly shows that non‐poor households prefer to use clean energy (i.e. solar) for lighting, while poor households tend to use solid fuel. Energy policies for development should be based on the realistic proposition that fuelwood will remain the major source of energy for cooking for substantial proportions of the world’s population. Promotion of public education, social forestry schemes and fuel‐efficient improved chulhas should be encouraged in order to reduce household dependence on fuelwood. Moreover, devolving sufficient property rights over forest resources to local communities may help secure their broad‐based and active participation in the decision‐making process, which may result in a positive change in the attitude of the local people towards biodiversity conservation.     

Spatial Variability of Groundwater Depth and Quality Parameters in the National Capital Territory of Delhi

The groundwater quantity and quality scenario is of much concern in the National Capital Territory of Delhi, India, which necessitates an investigation to envisage the extent of spatial variability of groundwater depth and pollutant concentration levels in this region. Therefore, in this study, an effort was made to generate the spatial variability map of groundwater depth and quality parameters (viz. chloride, electrical conductivity, fluoride, magnesium, and nitrate). Ordinary kriging was used to analyze the spatial variability of groundwater depth and quality parameters, whereas indicator kriging was used to analyze groundwater quality parameters equal to or greater than the pollution threshold values. It was observed that the semivariogram parameters fitted well in the exponential model for water depth and in the spherical model for water quality parameters. The generated spatial variability maps indicated that in 43% of the study area, groundwater depth was within 20 m. The salinity level was higher than 2.5 dS m⁻¹ in 69% of the study area and the nitrate concentration exceeded 45 mg l⁻¹ in 36% of the area. The probability maps showed that about 24% of the area had the highest probability (0.8–1.0) of exceedence of the threshold electrical conductivity value and an area of 2% exhibited the highest probability of exceedence of the threshold value of nitrate concentration in the groundwater. The generated spatial variability and probability maps will assist water resource managers and policymakers in development of guidelines in judicious management of groundwater resources for agricultural and drinking purposes in the study area.     

Influence of land use and land cover on the spatial variability of dissolved organic matter in multiple aquatic environments

Environmental Science and Pollution Research - Water quality of lakes, estuaries, and coastal areas serves as an indicator of the overall health of aquatic ecosystems as well as the health of the...     

Survey on awareness and attitudes of secondary school students regarding plastic pollution: implications for environmental education and public health in Sharjah city,UAE

Environmental Science and Pollution Research - Since the industrial revolution in the 1800s, plastic pollution is becoming a global reality. This study aims to assess knowledge and attitude about...