Minimizing changing climate impact on buildings using easily and economically feasible earth to air heat exchanger technique

The biggest challenge of the 21st century is to satisfy the escalating demand of energy and minimize the globally changing climate impact. Earth to air heat exchanger (EAHE) system can effectively reduce heating affects on buildings. An experimental study was carried out by designing EAHE system using low cost building materials like Bamboo (Bambuseae) and hydraform (cement and soil plaster) to reduce the energy consumption of buildings and minimize the impact of climate change. This system utilizes earth’s constant subterranean temperature for naturally heating or cooling the inlet air. This study was carried out in the North Eastern part of India. An open loop EAHE system was developed to predict the heating and cooling potential of the system. Within the system locally available bamboos were used for constructing the tunnel pipes and soil-cement mixture plaster was used to enhance the conductivity of the bamboo pipes. Soil-cement mixtures are capable of decreasing the humidity by 30 to 40 %. Majority of the North Eastern region of India, have humid climatic conditions through out the year. Experiment was performed continuously for 7 days and the result shows that irrespective to the inlet air temperature (ranges from 35 °C to 42 °C), outlet air temperature was recorded between 25 °C and 26 °C, which shows the effectiveness of the system. After a series of experimental analysis the study reveals that underground tunnel based fresh air delivery system is one of the easily feasible and economically feasible techniques which can drastically reduce the energy consumption of the buildings and help in addressing the continuously escalating demand of power and minimizing the impact of changing climatic conditions on buildings.     

Railway-Associated Attractants as Potential Contaminants for Wildlife

Environmental Management - Grizzly bears (Ursus arctos) appear to be attracted to natural and anthropogenic forage along railways, which may increase collision vulnerability, but also potentially...     

Effects of population and population pressure on forest resources and their conservation: a modeling study

In this paper, a nonlinear mathematical model is proposed and analyzed to study the depletion of forest resources caused by population and the corresponding population pressure. It is assumed that the cumulative density of forest resources and the density of populations follow logistic models with prey–predator type nonlinear interaction terms. It is considered that the carrying capacity of forest resources decreases by population pressure, the main focus of this paper. A conservation model is also proposed to control the population pressure by providing some economic incentives to people, the amount of which is assumed to be proportional to the population pressure. The model is analyzed by using stability theory of differential equations and numerical simulation. The model analysis shows that as the density of population or population pressure increases, the cumulative density of forest resources decreases, and the resources may become extinct if the population pressure becomes too large. It is also noted that by controlling the population pressure, using some economic incentives, the density of forest resources can be maintained at an equilibrium level, which is population density dependent. The simulation analysis of the model confirms analytical results.     

Organochlorine residues in water from the Mahala water reservoir, Jaipur, India

Residues of p,p'-DDE, p,p'-DDT alpha-, beta-, gamma-isomers of HCH, aldrin and heptachlor in water, from four different sites of the Mahala water reservoir were monitored periodically from September 1985 to October 1987. All the samples contained the above residues in varying concentrations. Isomers of HCH predominated and were followed in relative dominance by aldrin, total DDT and heptachlor residues, p,p'-DDE and p,p'-DDD constituted the major fraction of total p,p'-DDT. Monthly total organochlorine residue levels in water ranged between 1.07 and 81.23 microg litre-1. The variation is attributed to the run-off or subsoil water movement from the catchment area.     

Collective action: an alternative institutional arrangement for reducing water pollution in an industrial estate in India

This study explores the possibility of collective action as an alternative option for reducing water pollution for a cluster of small-scale industries. A case study of the Nandesari Industrial Estate in Gujarat, India, demonstrates the roles played by different agents, such as affected parties, polluters, non-governmental organizations, regulators and the court. The study empirically estimates the 'benefits' and 'costs' of water pollution abatement for a cluster of 250 small-scale industries at Nandesari, and uses these estimates for a social cost-benefit analysis. Benefits are estimated using the contingent valuation method, with a 'willingness to accept' format for the rural areas, and a 'willingness to pay' format for the urban area of the nearby Vadodara city. The article considers costs of command and control, market-based solutions and the option of common effluent treatment as alternative scenarios. It discusses how collective action and joint abatement at a common effluent treatment plant (CETP) by the 250 industries efficiently comply with the State Pollution Control Board norms, which had not been possible for the factories acting individually over the last 20 years. Finally, a detailed social cost-benefit analysis has been undertaken to estimate the net present social benefits with and without CETP. The cost-benefit analysis shows the economic advantage and social desirability of 'collective action' (joint treatment with CETP institutional arrangement) for water pollution abatement with respect to all possible scenarios comprising shadow prices of investment, foreign exchange, unskilled labour and equity considerations.     

Do we understand trends in atmospheric sulfur species?

Anomalies appear to exist in our understanding of atmospheric sulfur compounds, specifically as evidenced in the time trends of the different chemical forms of these compounds. Trends determined at a number of locations by several different groups seem to indicate that, responding to emission reductions across North America, the concentration of SO2 in the atmosphere is declining more rapidly than that of aerosol SO4(2-). A number of possible reasons for this discrepancy are examined, but it is not possible to provide a definitive answer at this stage. The intent is to stimulate debate, because shortcomings in our understanding of the processes involved could have profound implications for the credibility of abatement strategies and policies for both acid deposition and fine particulate matter (PM).     

Sexual coercion by male chimpanzees shows that female choice may be more apparent than real

The extent to which active female mating preferences influence male reproductive success in mammals is unclear, particularly for promiscuously breeding species like chimpanzees (Pan troglodytes). Previous studies from multiple long-term study sites have shown that female chimpanzees mate more restrictively around ovulation, and this has been taken as evidence for female choice. However, none of these studies rigorously evaluated the alternative hypothesis that restrictive mating results not from unconstrained choice, but in response to coercive mate guarding, in which males use punishment and intimidation to reduce female promiscuity and promote their own mating interests. Nor did they consider evidence for the potential genetic or phenotypic benefits that females might be choosing. Using 11 years of data from the Kanyawara community in Kibale National Park, Uganda, we previously demonstrated that males achieve elevated mating success with those females toward whom they direct high levels of aggression. Here we extend those findings to show that even female copulatory approaches, which have previously been attributed to female choice, are correlated with male aggression. Specifically, individual females at our site initiated periovulatory copulations most frequently with the males who were most aggressive toward them throughout their cycles. Those males showed high rates of aggression toward females throughout estrus, despite achieving high copulation rates, demonstrating a continuing conflict of interest over the exclusivity of mating access. Because sexual coercion is potentially widespread in primates and other mammals, our results stress the importance of considering the influence of male aggression in studies of female choice.