VENTILATORY RESPONSES OF BLUEGILL SUNFISH TO SUBLETHAL,FLUCTUATING EXPOSURES TO HEAVY METALS (Zn++ and Cu++)1

ABSTRACT Minicomputer interfaced, continuous, noncontact sensing of the ventilatory behavior of the bluegill (Lepomis macrochirus) was used to investigate the response to exposure to solutions of copper and zinc under various modes of application. The results of these studies indicate that fish respond to sublethal concentrations of these toxicants by increasing the average ventilatory rate as well as decreasing the amplitude of the ventilatory signal. Appropriate statistics for the analysis of these data are also described.     

Assessment of risk in a minerals industry: Canadian nickel

The level of rents attributable to natural resource producers depends on the risk faced by those producers. This paper argues that estimates of risk in mining should control for characteristics of firms such as diversification and debt financing. The capital asset pricing model is applied to securities of three Canadian nickel mining firms over the period 1961–1974. It is concluded that the level of risk was not unusually high.     

A synopsis of the book Ecological Indicators for the Nation John Cairns, Jr

The U.S. Environmental Protection Agency requested the National Research Council(which is the operating arm of the U.S. National Academy of Sciences and the U.S. National Academy of Engineering) to carry out a critical scientific evaluation of indicators to monitor ecological changes from either natural or anthropogenic causes. More specifically, the National Research Council was asked to identify criteria for evaluating biological indicators, to evaluate methods of indicator development, to provide examples of ndicators that have proven useful, and to identify areas where further research is likely to yield more useful and powerful indicators. In addition, the National Research Council was to examine what aspects of environmental conditions and trends should be monitored.     

Macroinvertebrate assemblages of surface mine wetlands of Southwest Virginia,USA

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A model of exhaustible resource exploitation with ricardian rent

The question of the optimal rate of development of an exhaustible resource (such as a mine) has long been a concern of resource economists. However, with few exceptions in the literature, it has been implicitly assumed that orebodies are of uniform quality, readily distinguished from their surroundings, or else that the mining firm is able to choose the order of mining from sections of the mine which may vary in quality (e.g., grade of ore). While such simplifying assumptions have led to a rich array of conclusions, they stand in contrast to the varying conditions facing the mining engineer in making cut-off grade decisions. This paper models a situation where, because of orebody configurations, the firm cannot choose to mine in order of grade. An optimal cut-off grade is obtained for each point of time of the mine's life in the case of a socially optimizing firm. Then in a special case the effects of monopoly and various types of mineral taxation are considered for the cut-off grade decision and for ultimate recovery.     

An evaluation of the PM2.5 trace elemental composition in the Venice Lagoon area and an analysis of the possible sources

Global emissions reported by many authors have shown as natural and anthropic sources can contribute to the principal aerosol classes, but values change according the local scenario. The Venice Lagoon is exposed to different anthropic source emissions like vehicular traffic, industrial thermoelectric power plant, petrochemical plant, incinerator plant, domestic heating, ship traffic, glass factories and airport. Samplings of PM_2.5 were daily performed between March and November 2007 in Sacca San Biagio island (Venice), and values of PM_2.5 concentration and element concentration were obtained. Monthly average concentrations (μg m^?3) during this period show higher values during the spring and the autumn. A good relationship between data obtained and concentration values from environmental local agencies is evidenced, both for PM_2.5 from urban area (Venezia Mestre), and for PM₁₀ sampled in the same area, as well as the influence of some meteorological parameters on PM_2.5 concentration sampled. Trace elements samples were measured by an Inductively Coupled Plasma-Quadrupole Mass Spectrometry (ICP-QMS), and values (ng m^?3 and μg g^?1) for elements regulated by European directives (As, Cd, Ni, Pb), as well as, other elements (Na, Al, K, Ti, V, Mn, Fe, Co, Zn, Se, Ag) are also reported. Data analysis by mean of Principal Component Analysis (PCA) and Positive Matrix Factorization (PMF) pointed out four principal groups of elements like Mn–Fe–K, As–Se–Cd, V–Co, and Pb that could be assigned to specific sources of the Venetian wetland basin.     

War and sustainability

SUMMARY

In order to use the planet's ecological life-support systems sustainably, damage to them must be both prevented and repaired. However, repair requires awareness of damage which, in this case, mandates a high level of ecological literacy. Prevention of ecological damage will only be successful on a planetary scale if human society endorses precautionary practices that reduce the probability of ecosystem damage. Society is beginning to endorse precautionary practices to protect human health, which is no longer regarded as merely absence of symptoms of disease and malfunction. Health is regarded as a robust function — an approach toward optimal conditions. Similar views are beginning to emerge regarding ecosystem health, and a close link between human and ecosystem health is gaining increased recognition. However, to achieve health, ecological ‘wounds’ must be repaired, which is impossible until society ‘sees’ the wounds. After this recognition, society must become more literate on the attributes of ecosystem health. The methods and procedures are in place, but they will not be used effectively until a major paradigm shift occurs.     

Materialphilia,biophilia, and sustainable use of the planet

SUMMARY

The intricate and complex relationships between transhumant pastoralists, livestock and environment at the high altitudes of Indian Central Himalaya has started to break down at an alarming rate. Some of the important factors attributed to this are depletion of grazing resources, commercialization of the rural economy, and integration of these communities with the mainstream of development through education and employment. Traditionally these livestock were assigned different roles in society depending upon their economic benefit and utility. The roles which once depended upon attitude to various risks, such as environmental, social and economic, have lost their significance due to changing of the production process. This paper gives an overview of the various types of roles the livestock played in the transhumant society, and how they are being replaced by the developmental process in the region, and whether the changes are sustainable for such remote regions in a developing country.     

Eco-ethical issues: Self-regulating versus subsidized ecosystems

Sustainable use of the planet requires dependable delivery of ecosystem services at a level necessary to meet the needs of humankind. During the last two centuries, particularly in the twentieth century, ecosystems have been fragmented and stressed in a variety of ways, including biotic impoverishment. Self-regulating ecosystems are capable of maintaining nominative structure and function, including normal variability. Those ecosystems incapable of self regulation will require subsidies, which will divert resources from other activities that may also be important to sustainable use of the planet. If ecosystems are not subsidized, the loss of natural capital and ecosystem services will almost certainly impair the quest for sustainable use of the planet. Although most discussions of sustainability reflect an awareness of humankind's dependence on natural systems, ecosystem self regulation has not received an adequate amount of attention.     

Designing for nature and sustainability

Humankind is now using natural resources more rapidly than natural systems can replace them and has been doing so for approximately two and a half decades. Moreover, both natural capital and the ecosystem services it provides are being diminished at an unprecedented rate. Finally, the human population is expected to increase by three billion by 2050. This situation is clearly unsustainable, but it can be made less so by redesigning societal wastes so that they benefit the biospheric life-support system. Nature initiates and maintains a system of energy and nutrient cycling and, if the system integrity is maintained, provides alternative and redundant means that help stabilize functional capacity. The system is composed of opportunistic individuals that compete with other individuals to acquire the resources essential to their survival. The interrelationships within this aggregation of individuals (i.e. system components) are based on energy flow. This self-organizing and self-maintaining system is increasingly stressed by human activities. Humans are a part of, not apart from, this system and are governed by the same laws of nature. In short, an ecologically-based economic system is essential to sustainable use of the planet. The planet's life-support system has been a superb model of sustainability, which humans should emulate and become a part of more than they now are. When the biospheric life-support system is stressed to the point of disequilibrium, the results are disastrous for societies, individuals and ecosystems. Evolutionary processes have produced replacement systems following the five great biological extinctions. However, the probability is high that the next replacement system will not be as suitable for humankind as the present system. Sustainable practices are intended to prevent biospheric disequilibrium and maintain the present environmental conditions so favorable to humankind, including posterity.