Ecosystem Health最新文献

ABSTRACT

The influences of human-caused changes in a natural ecosystem of Southern Brazil on mosquitoes of the family Culicidae, which may be vectors of diseases, were investigated. Particular attention was given to the effects of deforestation and human settlements with artificial irrigation. The work assumes a preserved environment as representative of the natural ecosystem before human intervention. Another collection site, 50 kilometers from the primitive forest, that presented the same fauna and flora of the former some 50 years ago was chosen as the modified environment. The results clearly showed that some species, such as the Kerteszia subgenus, do not survive these changes, whereas others have found such conditions favorable and have proliferated.

ABSTRACT

The scale of environmental hazards to human population health is increasing. For the first time, the human species is perturbing various natural systems at the global level. Over many millennia, humans have often degraded local ecosystems, and their societies then usually suffered or moved. What differs in today’s world is the global, systemic, scale of human impact. This reflects the aggregate impact of rapidly increasing population size and an energy-intensive high-throughput linear consumer economy. In consequence, we are now encountering anthropogenic changes in the composition of the world’s lower and middle atmospheres and the worldwide depletion of other natural systems (e.g., soil fertility, aquifers, ocean fisheries, and biological diversity).

We have long overlooked the fundamental infrastructural importance to human health of the biosphere’s natural systems. Yet, these are the life-support systems upon which the sustained health of populations depends. In many respects, the potential health risks from global environmental change are therefore qualitatively different from the well-known, locally confined environmental risks to health from direct-acting toxic pollutants. Disruption of natural biophysical systems jeopardizes human health by a range of direct and indirect, immediate and delayed mechanisms. These entail major implications for the longer-term sustainability of human population health. We therefore must extend our health risk assessment concepts and methods to accommodate scenario-based forecasting of health impacts. There is need for an expanded transdisciplinary research effort that would include the development of new and better modelling and predictive techniques. These research methods and the communication of research results to public and policymaker must accommodate an unusual mix of complexity, uncertainty, and futurism.

The extent and profile of health impacts from global environmental change will vary around the world. In general, poor, restricted, and isolated populations will be the most vulnerable. The combined impacts of climate change, freshwater shortages, and land degradation may impair agricultural productivity most in subtropical and semi-arid regions where food insecurity is already prevalent. Clearly, there are complex political and ethical challenges that accompany the challenges to science.

ABSTRACT

Many ecologists express difficulty with the concept of ecosystem health. Ecosystem health must have definable and objective norms that allow for rigorous hypothesis testing for it to be acceptable to those ecologists. One step toward objective measurement of ecosystem health is to characterize ecosystem health by diversity–abundance relationships. The log-normal relationship between diversity and abundance characterizes taxocenes (i.e., taxonomically related groups that have similar ecological functions). Under conditions of stress, the patterns of diversity and abundance often change and are no longer log-normal. This change in patterns has been shown for some, but not all, marine and terrestrial taxocenes tested. The interdisciplinary possibilities for using log-normality, and deviation from it, as a measure of natural and anthropogenic ecosystem health are discussed. The interdisciplinarity of ecosystem health is illustrated with an example of blueberry pollinator decline caused by insecticide spraying in New Brunswick, Canada, and related economic and human health costs.

ABSTRACT

In this article, I consider the implications of gender differences for determining acceptable risk. Although often unacknowledged, values are ineradicable from risk identification, estimation, and acceptability. Because empirical studies, including some conducted by McMaster University’s Eco-Research group, show significant gender differences in risk assessment, democratic decisions about acceptable risk must reflect the values of females as well as males. I argue that Kristin Shrader-Frechette’s model of scientific proceduralism, modified to incorporate findings about gender differences, can contribute to fairness in decision-making about risk. Furthermore, because females are more environmentally concerned than are males, especially at local levels, ecosystem health would be well-served by decentralizing environmental decision-making and ensuring gender representation.