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131.
Mammalian communities were studied on 10 surface mines over a four year period. The size and composition of these communities varied among the different areas. The size, composition, and spatial distribution of these mammalian communities were related to the structure of the plant community, and native plant species were of greater importance in determining size and composition of these communities than were those used in reclamation. 相似文献
132.
Hallock P Lidz BH Cockey-Burkhard EM Donnelly KB 《Environmental monitoring and assessment》2003,81(1-3):221-238
Coral reef communities are threatened worldwide. Resource managers urgently need indicators of the biological condition of reef environments that can relate data acquired through remote-sensing, water-quality and benthic-community monitoring to stress responses in reef organisms. The FORAM (Foraminifera in Reef Assessment and Monitoring) Index (FI) is based on 30 years of research on reef sediments and reef-dwelling larger foraminifers. These shelled protists are ideal indicator organisms because: Foraminifers are widely used as environmental and paleoenvironmental indicators in many contexts; Reef-building, zooxanthellate corals and foraminifers with algal symbionts have similar water-quality requirements; The relatively short life spans of foraminifers as compared with long-lived colonial corals facilitate differentiation between long-term water-quality decline and episodic stress events; Foraminifers are relatively small and abundant, permitting statistically significant sample sizes to be collected quickly and relatively inexpensively, ideally as a component of comprehensive monitoring programs; and Collection of foraminifers has minimal impact on reef resources.USEPA guidelines for ecological indicators are used to evaluate the FI. Data required are foraminiferal assemblages from surface sediments of reef-associated environments. The FI provides resource managers with a simple procedure for determining the suitability of benthic environments for communities dominated by algal symbiotic organisms. The FI can be applied independently, or incorporated into existing or planned monitoring efforts. The simple calculations require limited computer capabilities and therefore can be applied readily to reef-associated environments worldwide. In addition, the foraminiferal shells collected can be subjected to morphometric and geochemical analyses in areas of suspected heavy-metal pollution, and the data sets for the index can be used with other monitoring data in detailed multidimensional assessments. 相似文献
133.
The multiple and interlinked problems that plague most peri-urban communities can only be successfully addressed and resolved if roles and responsibilities of all actors in the urban setting are redistributed. This will require fundamental changes in the way municipalities work and define their accomplishments. Behaviour needs to change at all levels, beginning with public sector institutions responsible for communities. Without changes at the municipal level, requisite changes at the community level to remedy the root causes of environment-related illness, do not occur. Public sector institutions and communities, working as partners with clearly defined roles and responsibilities, and, most importantly, with mutual trust, can together make real progress toward improving health and well-being in peri-urban settlements. This article discusses two recent projects sponsored by the Environmental Health Project of the U.S. Agency for International Development (USAID): an 18-month pilot project to improve peri-urban environmental health in two cities in Tunisia, and a project in Ecuador to support the Ministry of Health in combating cholera in affected provinces. The following examples, methodology, and results may be useful to officials and donor organizations in designing environmental health projects. 相似文献
134.
Kelly M 《Disasters》1993,17(2):110-121
Recent experience of emergency relief operations in middle-income countries has shown that infant feeding issues can greatly complicate attempts to protect infant health. The two main problems are: how to protect and support breastfeeding in communities where it is no longer the norm and how to assist artificially fed infants without exposing them to the dramatically increased risks associated with artificial feeding under disaster conditions. This article explores the underlying issues and makes a number of recommendations for policy and programmes. 相似文献
135.
Edwards GS Wullschleger SD Kelly JM 《Environmental pollution (Barking, Essex : 1987)》1994,83(1-2):215-221
Considerable progress has been made during the past decade in the development of mechanistic models that allow complex chemical, physical, and biological processes to be evaluated in the global change context. However, quantitative predictions of the response of individual trees, stands, and forest ecosystems to pollutants and climatic variables require extrapolation of existing data sets, derived largely from seedling studies, to increasing levels of complexity with little or no understanding of the uncertainties associated with these extrapolations. Consequently, a project designed to address concerns associated with scaling from seedling to mature tree responses was initiated. During the 1990 and 1991 growing seasons, mature northern red oak (Quercus rubra L.) trees and seedlings were exposed to subambient, ambient, and twice ambient ozone (O(3)) concentrations. The initial focus of the study was to identify possible trends and obvious differences between mature trees and seedlings, both in terms of growth and physiology and in response to O(3). Generally, mature trees exhibited a greater decrease in photosynthesis rates over the growing season than did the seedlings. Ozone treatments had no consistent effect on gas exchange rates of seedlings, but the twice ambient O(3) treatment resulted in reduced photosynthesis rates in the mature tree. Despite no effect of O(3) on seedling gas exchange rates, total seedling biomass was significantly less at the end of the 1991 growing season for those seedlings exposed to twice ambient O(3) levels. Disproportionate reductions in root biomass also resulted in reduced root to shoot ratios at elevated O(3) concentrations. 相似文献
136.
David Wainhouse Tristram Wyatt Alun Phillips David R. Kelly Mehrdad Barghian Paul Beech-Garwood David Cross Rex S. Howell 《Chemoecology》1991,2(1):55-63
Summary Adults of the predatory beetleRhizophagus grandis are strongly attracted to both adult and larval frass of its specific prey,Dendroctonus micans, in walking bioassays. Spruce bark and resin are relatively unattractive. Solvent extracts of larval frass that were attractive toR. grandis adults in a flight wind tunnel contained a mixture of monoterpenes of host plant origin. A synthetic mixture of these monoterpenes, (+)—-pinene, (–)—-pinene, -phellandrene,dl limonene and 3-carene, was responsible for 70–80% of the activity of the most attractive extract. We suggest that a blend of monoterpenes in frass acts as a kairomone forR. grandis but that attraction to monoterpenes is only the first of a sequence of behavioural responses that ensures successful host location and identification. 相似文献
137.
Theory into Practice: Implementing Ecosystem Management Objectives in the USDA Forest Service 总被引:5,自引:1,他引:5
In the United States and around the world, scientists and practitioners have debated the definition and merits of ecosystem management as a new approach to natural resource management. While these debates continue, a growing number of organizations formally have adopted ecosystem management. However, adoption does not necessarily lead to successful implementation, and theories are not always put into practice. In this article, we examine how a leading natural resource agency, the United States Department of Agriculture Forest Service, has translated ecosystem management theory into concrete policy objectives and how successfully these objectives are perceived to be implemented throughout the national forest system. Through document analysis, interviews, and survey responses from 345 Forest Service managers (district rangers, forest supervisors, and regional foresters), we find that the agency has incorporated numerous ecosystem management components into its objectives. Agency managers perceive that the greatest attainment of such objectives is related to collaborative stewardship and integration of scientific information, areas in which the organization has considerable prior experience. The objectives perceived to be least attained are adaptive management and integration of social and economic information, areas requiring substantial new resources and a knowledge base not traditionally emphasized by natural resource managers. Overall, success in implementing ecosystem management objectives is linked to committed forest managers. 相似文献
138.
A Multiscale Conceptual Framework for Integrated Ecogeomorphological Research to Support Stream Naturalization in the Agricultural Midwest 总被引:1,自引:0,他引:1
The complexity of fluvial systems necessitates interdisciplinary research in fluvial geomorphology and aquatic ecology to
develop a fundamental understanding of interconnections among biotic and abiotic aspects of these systems. Integrated knowledge
of this type is vital for environmental management of streams in human-dominated environments. A conceptual framework is presented
for integrating geomorphological and ecological research on streams in East Central Illinois, USA, a glaciated low-relief
agricultural landscape. The framework embodies a multiscale perspective in which a geomorphological conception of the fluvial
system is used to define a hierarchy of characteristic spatial scales for exploring important linkages between stream geomorphology
and aquatic ecology. The focus ecologically is on fish, because a rich body of historical information exists on fisheries
in East Central Illinois and because past work has suggested that availability of physical habitat is a major factor influencing
the community characteristics of fish in this human-altered environment. The hierarchy embodied in the framework includes
the network, link, planform, bar unit, bar element, and bedform/grain scales. Background knowledge from past research is drawn
upon to identify potential linkages between geomorphological and ecological conditions at each of these scales.
The conceptual framework is useful for guiding integrated ecogeomorphological research at specific scales and across different
scales. It also is helpful for illustrating how widespread human modification of streams has catastrophically altered the
scalar structure of fluvial systems in East Central Illinois. Knowledge emerging from the integrated research provides a basis
for environmental-management schemes directed toward stream naturalization. 相似文献
139.
Although the transactional model of the stress process (Lazarus, 1966, 1993; Lazarus and Folkman, 1984, 1987) continues to be utilized in a significant amount of stress research, much of the current literature on job stress focuses on pinpointing objective stressors. This paper examines Lazarus' transactional appraisal approach and includes a specific discussion of the process by which employees' attributions regarding stressors and the resulting emotions significantly influence their choices of coping mechanisms. Given that a single work event can be interpreted in a variety of ways, the role of individuals' cognitive processing is being ignored by much of the current empirical stress research. This paper examines and highlights the importance of the cognitive and emotional components within the organizational stress process. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
140.
Leaching and sorption of neonicotinoid insecticides and fungicides from seed coatings 总被引:1,自引:0,他引:1
Kelly L. Smalling Michelle L. Hladik Corey J. Sanders Kathryn M. Kuivila 《Journal of environmental science and health. Part. B》2018,53(3):176-183
Seed coatings are a treatment used on a variety of crops to improve production and offer protection against pests and fungal outbreaks. The leaching of the active ingredients associated with the seed coatings and the sorption to soil was evaluated under laboratory conditions using commercially available corn and soybean seeds to study the fate and transport of these pesticides under controlled conditions. The active ingredients (AI) included one neonicotinoid insecticide (thiamethoxam) and five fungicides (azoxystrobin, fludioxonil, metalaxyl, sedaxane thiabendazole). An aqueous leaching experiment was conducted with treated corn and soybean seeds. Leaching potential was a function of solubility and seed type. The leaching of fludioxonil, was dependent on seed type with a shorter time to equilibrium on the corn compared to the soybean seeds. Sorption experiments with the treated seeds and a solution of the AIs were conducted using three different soil types. Sorption behavior was a function of soil organic matter as well as seed type. For most AIs, a negative relationship was observed between the aqueous concentration and the log Koc. Sorption to all soils tested was limited for the hydrophilic pesticides thiamethoxam and metalaxyl. However, partitioning for the more hydrophobic fungicides was dependent on both seed type and soil properties. The mobility of fludioxonil in the sorption experiment varied by seed type indicating that the adjuvants associated with the seed coating could potentially play a role in the environmental fate of fludioxonil. This is the first study to assess, under laboratory conditions, the fate of pesticides associated with seed coatings using commercially available treated seeds. This information can be used to understand how alterations in agricultural practices (e.g., increasing use of seed treatments) can impact the exposure (concentration and duration) and potential effects of these chemicals to aquatic and terrestrial organisms. 相似文献