N:P stoichiometry and transparent exopolymeric particles buffer ecological impacts of nutrients in the Ganga River: a mesocosm study

We investigated the possible drivers of the N:P stoichiometric shift and its relationship with micro-algal production of transparent exopolymeric particles (TEP) along a 35?km gradient of the Ganga River. The objective was to evaluate if the trade-off between N:P stoichiometry and production of TEP helps in maintaining water quality of the river. Mesocosm experiments were conducted to examine N:P-TEP linkages and its role in turbidity removal. In situ measurements did not show Si to be a limiting nutrient (N:Si?Aulacosira granulata and Fragilaria intermedia. Settling efficiency, turbidity removal and sedimentation of TEP, biogenic silica (BSi) and biomass all increased with decreasing N:P ratio proportionately to the amount of TEP produced in the mesocosm. The study demonstrates that trade-off between N:P stoichiometry and the production of TEP generates feedback to buffer the ecological impacts of nutrient pollution.     

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Pharmacological significance of marine microbial bioactive compounds

Environmental Chemistry Letters - The continuous growth of the world population has raised heatlh issues such as the inefficiency of common drugs, such as antibiotics, due to...     

Evaluations of a sacred place: Role and religious belief at the Magh Mela

People perceive places differently because of the different material, social, and symbolic aspects of the locations and because individuals have different backgrounds and different reasons for being at the locations. Two studies examined how role and religious beliefs affect perceptions of the environment at the Magh Mela, an annual religious festival at the confluence of the Ganges and Yamuna Rivers in north India. In the first study (n=375), we interviewed individuals who were at the Mela for one of six reasons (religious pilgrims, sweepers, boatmen, police, businessmen, or student volunteers) about their religious beliefs and their perceptions of the Mela. Results indicated that the evaluations of pilgrims, who were at the Mela for religious reasons, were associated with evaluations of physical amenities and religious social support, whereas the other five groups, who were at the Mela primarily for nonreligious purposes, evaluated the Mela on the basis of material characteristics only. In the second study (n=311), we found that religious leaders’ evaluations of the Mela were affected by material characteristics, religious social support, and intrinsic religious belief.     

Experimental Studies of the Conditions of Exposure to Carcinogens for Lung Cancer Induction

A method is described for the experimental induction of lung cancer. Syrian golden hamsters, receiving repeated intratracheal administrations of benzo[a]pyrene in particulate form carried by an inert dust, develop a high incidence of bronchogenic carcinoma. The conditions of exposure to the carcinogen, involving penetration and retention of carcinogen particles in lung tissues with the dust, are of prime imvortance in the determination of the results. Instillations of the same carcinogen in other media did not induce lung tumors. The relative importance of the identification of carcinogenic materials in air pollution and of the conditions of exposure in the origin of lung cancer is discussed.     

Environmental change and vulnerability in the Usangu plain,southwestern Tanzania: Implications for sustainable development

Natural resources are important assets for sustainability of rural livelihoods and economic development. The objectives of the study were to assess linkage of environmental change to emerging water scarcity, livelihoods insecurity and decline in wildlife biodiversity and hydropower generation in the Great Ruaha ecosystem, and to discuss policy lessons for sustainable development. Literature survey, participatory assessments, collection of records from stakeholders, participatory observations and a questionnaire survey were used. Participatory assessment found that increasing water scarcity is associated with degradation of land, vegetation cover and change in rainfall intensity and duration. Rainfall change is supported by 83% of respondents and rainfall trends analysis. About 42% of variation in cereal production is described by the rainfall amount variability. Analysis of trends for per capita cereals production from district records showed a significant (p < 0.05) decline over the years. Changes in water flows in the Great Ruaha River have been evident since 1993, and have affected wildlife diversity in the Ruaha National Park and power generation from the Kidatu hydroelectric plant downstream. Human livelihood activities, exclusiveness, weak coordination and collaboration between sectors and institutions in policy formulation and implementation have played a role. The pro-poor policy formulation through integrated planning, strong coordination and collaboration is recommended for sustainable development.