Plagiochasma appendiculatum as a biotest for water quality assessment

A thalloid pathogen-free liverwort, Plagiochasma appendiculatum, was exposed to different pollution stresses, especially heavy metals, synthesized in the laboratory, to simulate pollutants reported to occur in industrial areas. The plant was found to be sensitive to mercury and copper. Thallus injury and chlorophyll content showed effects with increasing exposure to metals. In contrast, the plant was found to be resistant to lead, zinc and chromium. The plant showed growth in some concentrations of these metals, hence suggesting their accumulation. In this paper, the possible use of Plagiochasma in the assessment of water quality, especially for heavy metals, is discussed, with special reference to thallus deterioration as a simple biomonitoring parameter.     

Landscape ecological planning through a multi-scale characterization of pattern: studies in the Western Ghats,South India

This article analyzes landscape pattern in the WesternGhats mountain ranges in south-western India at two scales,comparing small-scale, detailed studies of landscapepattern, with broader, regional-scale assessments of theWestern Ghats. Due in large part to their inaccessibility,relatively little is known about the landscapes of thisbiodiverse region, which also supports some of the highestpopulation densities in the world. A broad-scale NDVI-basedIRS 1B satellite image classification is used to analyzenorth-south and east-west trends across the entire WesternGhats and western coast of India, an area over 170 000 km². Northern and eastern landscapes are morefragmented compared to the southern and western slopes.Western slopes also have greater landscape diversity withland cover types more interspersed compared to the easternslopes. These differences can be related to north-south andeast-west variations in rainfall and plant distribution. Data from thirteen landscapes 10–50 km² in area, arefurther utilized to analyze trends in landscape pattern, anddescribe the geographical distribution of major natural andmanaged ecotope types. At this scale, very high levels ofintra-ecotope type variability in landscape pattern areencountered for all land cover types. Results at these twoscales are integrated to suggest a hierarchical stratifiedapproach for monitoring land cover and biodiversity in the region.     

Evaluation of Acacia nilotica (L.) del. and Casuarina equisetifolia forst. for tolerance and growth on microbially treated dyestuff wastewater

Two tree species, Acacia nilotica (L.) Del. and Casuarina equisetifolia Forst., were tested for their tolerance and growth on dyestuff wastewater containing phenol, aniline, and methyl violet. The wastewater was treated microbially by using a culture of Pseudomonas alcaligenes in a fixed-film bioreactor. The plants were watered with untreated and treated wastewater and tap water (control) at the rate of 2 litre per plant per week. A. nilotica exhibited 100% survival with both untreated and treated wastewater, and growth (increase in height) was comparable to that of control plants. However, growth of C. equisetifolia was adversely affected. It exhibited 100% survival with treated wastewater but only 87% survival with untreated waste-water and the percentage increase in height was less with both treated and untreated wastewater. There was no effect on soil except for an increase in chloride content.     

Global gains at local costs: Imposing protected areas: evidence from central India

With the ever-increasing understanding about the Earth as a living network of interdependent ecosystems, there seems to be a growing consensus that the whole planet is a global common. This feeling, however, is not bereft of severe complications arising from conflicting interests of different nations placed at varying levels of development. While developed countries are more concerned about environmental quality which is a global public good, less developed countries can hardly afford to make land use decisions that keep such wider futuristic concerns in mind while they are presently struggling with very basic problems of poverty and starvation. The actors at the global level prescribe, monitor, and enforce the global level collective choice through persuasive, and at times coercive, methods. At the national level, various legal provisions in the form of legislation reflect the collective choice at that level through creation of protected areas devoid of humans. A simple fact is overlooked, that it is impossible to achieve conservation goals without making local people equal participants in decisionmaking and benefit sharing.     

Validation of an in situ solidification/stabilization technique for hazardous barium and cyanide waste for safe disposal into a secured landfill

The aim of the present study was to devise and validate an appropriate treatment process for disposal of hazardous barium and cyanide waste into a landfill at a Common Hazardous Waste Treatment Storage Disposal Facility (CHWTSDF). The waste was generated during the process of hardening of steel components and contains cyanide (reactive) and barium (toxic) as major contaminants. In the present study chemical fixation of the contaminants was carried out. The cyanide was treated by alkali chlorination with calcium hypochlorite and barium by precipitation with sodium sulfate as barium sulfate. The pretreated mixture was then solidified and stabilized by binding with a combination of slag cement, ordinary Portland cement and fly ash, molded into blocks (5 × 5 × 5 cm) and cured for a period of 3, 7 and 28 days. The final experiments were conducted with 18 recipe mixtures of waste + additive:binder (W:B) ratios. The W:B ratios were taken as 80:20, 70:30 and 50:50. The optimum proportions of additives and binders were finalized on the basis of the criteria of unconfined compressive strength and leachability. The leachability studies were conducted using the Toxicity Characteristic Leaching Procedure. The blocks were analyzed for various physical and leachable chemical parameters at the end of each curing period. Based on the results of the analysis, two recipe mixtures, with compositions – 50% of [waste + (120 g Ca(OCl)₂ + 290 g Na₂SO₄) kg^?1 of waste] + 50% of binders, were validated for in situ stabilization into a secured landfill of CHWTSDF.