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81.
This paper addresses questions of affective responses of residents of rural Arizona to changes in proximate community and riparian landscapes and the congruence of their perceptions of change with physical measures of change in those landscapes. Based on findings and concepts from previous studies, perceptions of change were assessed using a mail survey. Physical measures of land use and vegetation change were obtained from aerial photography for two points in time spanning approximately 13 years and were analyzed using a geographic information system. Significant differences were found in perceptions of change in the community and riparian landscapes. In contrast with previous findings, a majority of respondents found the changes as either improving or having no effect on landscape quality. Those who were more frequent users of the riparian landscape tended to be more aware of changes in it. The findings also suggest challenges for planners and resource managers working in rural areas adjacent to riparian landscapes. 相似文献
82.
A four-stage method of providing conditions for improving the stability of a landscape sector is presented. In the first stage,
structure and function of the landscape system is examined, predominantly based on the results of monitoring. In the second
stage, a method is suggested for applying monitoring data to a dynamic structure with complex functions of the territory under
examination. In the third stage, the territory is optimized as to the function of particular components within it. The optimization
consists in controlling the dynamics of the flows of material, energy, and population within the sector. In the fourth stage,
the holistic function of the landscape strip should be monitored with respect to representative key factors. The entire concept
is based on assuming the existence of destabilizing processes leading to ecocritical situations and determining mitigating
factors using heuristic methods of optimization. 相似文献
83.
Dr. Hana L. Ayala 《Environmental management》1987,11(2):141-147
We are witnessing a growing concern with the global dimension of many environmental issues, reflected in the increase in the number and significance of international environmental organizations. Yet there is no internationally applicable strategy for environmental research which is management oriented. A new type of research policy, which integrates ideas derived from environmental and human ecology, is required in order to deal with cultural and ecological diversity and their interactions as reflected in the ecology of landscapes. The newly defined concept of environmental health is proposed to fill this gap. This concept integrates the latest developments in landscape evolutionary ecology and environmental health, bringing out a conflict between making the environment conducive to human health and increasing the available options for supporting the essential biological and ecological processes of the environment. Lessons derived from the evolution of human environments are used in order to illustrate how health may become un umbrella for developing an environmental research policy, which could also serve as a catalyst for international environmental projects. 相似文献
84.
A multivariate statistical method for analyzing spatial patterns of water quality in Georgia and Kansas was tested using data in the US Environmental Protection Agency's STORET data system. Water quality data for Georgia and Kansas were organized by watersheds. We evaluated three questions: (a) can distinctive regional water quality patterns be detected and predicted using only a few water quality variables, (b) are regional water quality patterns correlated with terrestrial biotic regions, and (c) are regional water quality patterns correlated with fish distributions? Using existing data, this method can distinguish regions with water quality very different from the average conditions (as in Georgia), but it does not discriminate well between regions that do not have diverse water quality conditions (as in Kansas). Data that are spatially and temporally adequate for representing large regions and for multivariate statistical analysis are available for only a few common water quality parameters. Regional climate, lithology, and biotic regimes all have the potential to affect water quality, and terrestrial biotic regions and fish distributions do compare with regional water quality patterns, especially in a state like Georgia, where watershed characteristics are diverse. Thus, identifiable relationships between watershed characteristics and water quality should allow the development of an integrated landaquatic classification system that would be a valuable tool for resource management. Because geographical distributions of species may be limited by Zoogeographic and environmental factors, the recognition of patterns in fish distributions that correlate with regional water quality patterns could influence management strategies and aid regional assessments. 相似文献
85.
Robert G. Bailey 《Environmental management》1988,12(1):11-17
As part of the planning process, maps of natural factors are often superimposed in order to identify areas which are suitable or unsuitable for a particular type of resource management. Overlay maps may also be used to identify analysis areas for predictive modeling of resource productivity and ecological response to management. Current interest in applying computer-assisted mapping technology to making overlay maps is drawing attention to geographic information systems for this purpose. The resultant maps, however, may be so inaccurate or unable to capture significant units of productivity and ecological response that they could lead to imperfect or false conclusions. Recommendations are made on how to proceed in light of these problems. 相似文献
86.
Allan R. Ruff 《Journal of Environmental Planning and Management》1988,31(1):53-60
In Canada, increasing costs of maintenance, a shifting perception of what makes a city beautiful, a recognition of the needs and the importance of urban wildlife, and changing recreational demands are all contributing to a pressure for change in current practice. This study examines the extent to which the ecological approach has influenced the design and management of urban green space in Canada, focusing on the city of Toronto and its surrounding region as an example. 相似文献
87.
W. L. Nutter T. Tkacs P. B. Bush D. G. Neary 《Journal of the American Water Resources Association》1984,20(6):851-858
The breakpoint rainfall hydrology and pesticide options of the field scale model CREAMS (Chemicals, Runoff, and Erosion from Agricultural Management Systems) were used to predict average concentrations of hexazinone [3 cyclohexyl-6-(dimethyl-amino)-1-methyl-1,3,5-triazine-2,4(1H,3H)-dione] in stormflow from four forested watersheds in the upper Piedmont region of Georgia. Predicted concentrations were compared with measured concentrations recorded over a 13-month period. CREAMS accurately predicted hexazinone concetrations in the initial stormflow events which also contained the highest concentrations. The model underestimated the hexazinone concentrations in stormflow two months and greater following pesticide application. In a companion study, the daily rainfall option of the CREAMS model was used to evaluate the reltive risk associated with the maximum expected concentration of hexazinone, bromacil (5-bromo-3 sec-butyl-6 methyuracil), picloram (4-amino-3,5,6 trichloropicolinic acid), dicamba (3,6-dichloro-0-anisic acid), and triclopyr {[(3,5,6-trichloro-2-pyridinyl)oxy] acetic acid} in stormflow from small forested watersheds. The model predicted the following order of potential residue appearance in stormflow: bromacil>triclopyr>hexazinone>picloram>dicamba. Subsurface movement of residues via interflow and deep leaching losses are not simulated by the version of CREAMS used in these studies. 相似文献
88.
Our lack of understanding of relationships between stream biotic communities and surrounding landscape conditions makes it
difficult to determine the spatial scale at which management practices are best assessed. We investigated these relationships
in the Minnesota River Basin, which is divided into major watersheds and agroecoregions which are based on soil type, geologic parent material, landscape slope steepness, and climatic factors affecting crop productivity.
We collected macroinvertebrate and stream habitat data from 68 tributaries among three major watersheds and two agroecoregions.
We tested the effectiveness of the two landscape classification systems (i.e., watershed, agroecoregion) in explaining variance
in habitat and macroinvertebrate metrics, and analyzed the relative influence on macroinvertebrates of local habitat versus
regional characteristics. Macroinvertebrate community composition was most strongly influenced by local habitat; the variance
in habitat conditions was best explained at the scale of intersection of major watershed and agroecoregion (i.e., stream habitat
conditions were most homogeneous within the physical regions of intersection of these two landscape classification systems).
Our results are consistent with findings of other authors that most variation in macroinvertebrate community data from large
agricultural catchments is attributable to local physical conditions. Our results are the first to test the hypothesis and
demonstrate that the scale of intersection best explains these variances. The results suggest that management practices adjusted
for both watershed and ecoregion characteristics, with the goal of improving physical habitat characteristics of local streams,
may lead to better basin-wide water quality conditions and stream biological integrity. 相似文献
89.
R. E. Britter S. Di Sabatino F. Caton K. M. Cooke P. G. Simmonds G. Nickless 《Water, Air, & Soil Pollution: Focus》2002,2(5-6):79-90
The physical processes governing flow and pollutantdispersion at the neighbourhood scale, a spatial scaleintermediate between the street scale and the city scale, is notwell understood. Furthermore, it is not clear whether a traditional approach using averaged characteristics such as theaerodynamic roughness length is sufficient to predict the concentration field at this scale. To investigate pollutant dispersion in a real urban area, three field experiments were designed within the UK-URGENT programme sponsored by NERC. Theexperiments were performed in the City of Birmingham using a finite duration release of inert, non-toxic and non-depositingtracers, vis. perfluoromethylcyclohexane (PMCH) and perfluoromethylcyclopentane (PMCP). Measurements were taken using air bag samplers placedin an arc at 3.5 km (first experiment) and 1 km (second andthird experiments) from the source; some trap samplers wereplaced outside the main arc in the outskirts of the city. Measurements were analysed in the laboratory using anovel gas-chromatography technique. Data so obtained werecompared with predictions from a simple steady-state modeland a time-dependent model. The concentration-time serieswere very asymmetrical with a sharp rise, a plateau followedby a relatively slow decrease and finally a long-livedplateau above (or possibly very slow decrease to) thebackground level. 相似文献
90.
For about 50 years the desertion of areas by traditional activities has led to an important evolution of landscapes and environments
on the island of Ouessant. The study of this evolution has been undertaken at different spatial and temporal scales. On one
part of the island, a scientific investigation carried out at the scale of the parcel enabled the form of the landscape in
1850 to be compared with that of 1985. On the whole island, the evolution of spatial organization and land use was compared
between 1950 and 1985. For each of three main ecological environments, vegetational successions after the decrease of agriculture
have been studied along with their future potential changes. This work highlights some considerations about the present management
of the environment in relation to the major objectives of island environmental policies. 相似文献