Ecofriendly application of coconut coir (Cocos nucifera) extract for silk dyeing

Environmental Science and Pollution Research - The worldwide resurgence of natural dyes in all fields is due to the carcinogenic effects of effluent loads shed by synthetic industries. Coconut coir...     

Modelling land use change across elevation gradients in district Swat, Pakistan

District Swat is part of the high mountain Hindu-Kush Himalayan region of Pakistan. Documentation and analysis of land use change in this region is challenging due to very disparate accounts of the state of forest resources and limited accessible data. Such analysis is, however, important due to concerns over the degradation of forest land leading to deterioration of the protection of water catchments and exposure of highly erodible soils. Furthermore, the area is identified as hotspot for biodiversity loss. The aim of this paper is to identify geophysical and geographical factors related to land use change and model how these relationships vary across the district. For three selected zones across the elevation gradient of the district, we analyse land use change by studying land use maps for the years 1968, 1990 and 2007. In the high-altitude zone, the forest area decreased by 30.5 %, a third of which was caused by agricultural expansion. In the mid-elevation zone, agriculture expanded by 70.3 % and forests decreased by 49.7 %. In the lower altitudes, agriculture expansion was 129.9 % consuming 31.7 % of the forest area over the forty-year time period. Annual deforestation rates observed were 0.80, 1.28 and 1.86 % in high, mid and low altitudes, respectively. In the high-altitude ecosystems, accessibility (distance to nearest road and city) had no significant role in agriculture expansion; rather land use change appears significantly related to geophysical factors such as slope, aspect and altitude. In the low-elevation zone, accessibility was the factor showing the closest association with agriculture expansion and abandonment. The analysis illustrates that land use change processes vary quite considerably between different altitudinal and vegetation cover zones of the same district and that environmental constraints and stage of economic development provide important contextual information.     

Spillovers from global economic policy uncertainty and oil price volatility to the volatility of stock markets of oil importers and exporters

Economic policy uncertainty generally tends to induce a pessimistic view of future market behaviour. Furthermore, instabilities in global oil prices have serious implications for the economies of oil exporters and importers, due to their over-dependence on crude oil for revenue and production activities, respectively, and thereby on stock market indices. Against limited empirical evidence, this study examines the spillover effects from global economic policy uncertainty (GEPU) and oil price volatility to the volatility of the stock market indices of oil exporters and importers in both developed and emerging economies. The results show that the spillover effect from GEPU to oil exporters is relatively smaller than to oil importers, for both developed and emerging countries. Conversely, the volatility spillovers from oil prices to oil exporters are relatively larger than to oil importers, for both developed and emerging countries. Specifically, the volatility spillovers from oil prices to oil exporters (importers) in emerging countries are relatively stronger compared to oil exporters (importers) in developed countries. The findings indicate that the volatility of the stock markets of emerging countries is more sensitive to global factors such as GEPU and oil price volatility, and that oil exporters and importers in emerging economies are more sensitive to oil price volatility than oil exporters and importers in developed economies, which is in line with previous studies.

     

Indoor aerobiological pollution in certain indian domestic environments

The paper deals with bacterial and fungal populations and other pollutants in the indoors of slums, middle class, and upper class dwellings. Both allergenic and nonallergenic organisms have been observed to be higher in slums than in other dwellings. Further, females were more susceptible to various kinds of allergies than males.     

QUALITY OF WATER AND BOTTOM SEDIMENTS IN THE TRINITY RIVER1

ABSTRACT: Data were developed to determine the quality of water and bottom sediments in the Trinity River, and the mobility of various contaminants when bottom sediments were mixed with the river water under simulated dredging conditions. Thirteen sampling sites were selected. A number of chemical tests including heavy metals and pesticides were conducted on river water, elutriates, and bottom sediments. Statis bioassays using Daphnia magna were conducted on river water and elutriates. Results indicated that the river in the upper reach is grossly polluted due to discharge of waste water effluents from several large treatment plants. High concentrations of nitrogen, phosphorus, organic carbon, COD, heavy metals, and pesticides were found in water and bottom sediments. The concentrations of most of these pollutants exceeded the EPA recommended limits. Elutriation gave no consistent results, perhaps because of release or uptake of contaminants from the sediments. High mortality of D. magna were also recorded in the upper reach of the river. The quality of water and bottom sediments gradually improved in lower reaches.     

Growth kinetics and nutrient requirements of two tropical marine phytoplankters

Growth rates of nutrient-depleted cells of Biddulphia sinensis Greville and Ceratium furca (Ehrenberg) Claparède et Lachmann as a function of phosphate and nitrate, follow the hyperbolic expression of the Michaelis-Menten equation. variations in the half-saturation constants (K _s) for both species in each nutrient gave an index of their capacity to utilize these two nutrients when available either singly or in combination. The maximum growth rates (_max) of the two species did not follow the trends shown by K _s. Seasonal abundance of the two species in the Cochin Backwater (an Indian tropical estuary) showed that, at low concentrations of nutrients, C. furca becomes predominant; high nutrient concentrations present in the estuary during the monsoon months tend to increase the abundance of B. sinensis. The differences in the K _s values of the two organisms seem to reflect their observed seasonal abundance in the estuary.     

Antibiotic effect of exogenously applied salicylic acid on in vitro soilborne pathogen, Fusarium oxysporum f.sp.niveum

Salicylic acid, which is biosynthesized inside plant and is often found and accumulated in soil due to plant debris decaying, is considered as a signaling substance during plant-microbe interactions. It is involved in the cycling of biogeochemistry and related to plant resistance to biotic and abiotic stress. The antibiotic effect of salicylic acid on Fusarium oxysporum f.sp.niveum (FON) was studied to investigate the relationships between the salicylic acid and the fungus in the ecological interaction of plant-microbe. Results showed that the biomass, colony diameter, number of conidium germination and conidium production of FON were decreased by 52.0%, 25.7%, 100% and 100% at concentrations of 800 mg L(-1). However, mycotoxin yield was increased by 233%, pectinase activity raised by 168.0% and cellulase activity increased by 1325% compared to control at higher concentrations. It was concluded that salicylic acid as an allelochemical greatly inhibited FON growth and conidia formation and germination, though stimulated mycotoxin production and activities of hydrolytic enzymes by FON.     

Synthesis,Characterization and NH<Subscript>3</Subscript>/N<Subscript>2</Subscript> Gas Permeation Study of Nanocomposite Membranes

Carbon nanotubes have exceptional mechanical properties which make them very attractive for the development of composite membranes. In this research, NH₃/N₂ gas permeation behavior of flat sheet composite membranes was examined. The cellulose acetate-multiwalled carbon nanotubes composite membranes were synthesized using solution casting method. The morphology and dispersion of carbon nanotubes were observed through SEM. However, the composite membranes were also characterized using several analytical techniques such as X-ray diffraction analysis, tensile testing analysis, and thermal gravimetric analysis. Characterization of these membranes depicted that carboxylic group functionalized MWCNTs are extremely compatible with CA. The permeation experiments were performed with NH₃ and N₂ to explore the host–guest interaction of MWCNTs with chosen gases. The permeability of NH₃ was found pronounced compared to N₂. The NH₃/N₂ selectivity up to 90 was documented.