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541.
Fearnside PM 《Environmental management》2002,30(6):0735-0747
“Avança Brasil” (Forward Brazil) is a package of 338 projects throughout Brazil; the portion of the plan to be carried out in Brazil's Legal Amazon region totals US$43 billion over 8 years, US$20 billion of which would be for infrastructure causing environmental damage. Brazil's environmental impact assessment system is not yet capable of coping with the challenge presented by Avança Brasil. Generic problems with the licensing process include stimulation of a lobby in favor of construction before decisions are made on the advisability of the projects, the “dragging effect” of third parties, whereby economic activity is attracted to the infrastructure but escapes the environmental impact assessment system, a tendency for consulting firms to produce favorable reports, a bureaucratic emphasis on the existence of steps without regard to the content of what is said, and the inability to take account of the chain of events unleashed when a given project is undertaken.The environmental and social costs of forest loss are high; among them is loss of opportunities for sustainable use of the forest, including loss of environmental services such as biodiversity maintenance, water cycling, and carbon storage. The benefits of export infrastructure are meager, especially from the point of view of generating employment. Much of the transportation infrastructure is for soybeans, while the hydroelectric dams contribute to processing aluminum. The example of Avança Brasil makes clear the need to rethink how major development decisions are made and to reconsider a number of the plan's component projects. 相似文献
542.
Preventing groundwater contamination is vastly cheaper than remediation. Recognizing this, attention in water and land management
agencies in North America increasingly turn to groundwater protection. Local agencies, such as municipalities and watershed
management districts, are vital to successful groundwater protection, but they face daunting challenges. In the United States,
senior governments have recognized these challenges and provide considerable support for local agencies. In Ontario, Canada,
local agencies are, to a much greater extent, on their own. The aims in this paper are to analyze factors that shape local
capacity for groundwater protection, focusing on Ontario, and to recommend avenues for capacity building. Interrelationships
among five dimensions of capacity (technical, financial, institutional, social, and political) are explored through an analysis
of three smaller Ontario communities: City of Guelph (population 93,400), Town of Orangeville (population 22,188), and Town
of Erin (population 11,000). Size clearly influences capacity for groundwater protection. However, other considerations unrelated
to size appear to be as important. These other factors include the ability to form horizontal and vertical linkages with external
agencies, political leadership and commitment, and citizen involvement. Thus, smaller communities in Ontario (and other jurisdictions
with limited senior government support) would do well to focus on these areas at the same time as they develop their technical,
financial, and institutional capacity. 相似文献
543.
The US Army Engineering Research Development Center (ERDC) uses a modified form of the Revised Universal Soil Loss Equation
(RUSLE) to estimate spatially explicit rates of soil erosion by water across military training facilities. One modification
involves the RUSLE support practice factor (P factor), which is used to account for the effect of disturbance by human activities
on erosion rates. Since disturbance from off-road military vehicular traffic moving through complex landscapes varies spatially,
a spatially explicit nonlinear regression model (disturbance model) is used to predict the distribution of P factor values
across a training facility. This research analyzes the uncertainty in this model's disturbance predictions for the Fort Hood
training facility in order to determine both the spatial distribution of prediction uncertainty and the contribution of different
error sources to that uncertainty. This analysis shows that a three-category vegetation map used by the disturbance model
was the greatest source of prediction uncertainty, especially for the map categories shrub and tree. In areas mapped as grass,
modeling error (uncertainty associated with the model parameter estimates) was the largest uncertainty source. These results
indicate that the use of a high-quality vegetation map that is periodically updated to reflect current vegetation distributions,
would produce the greatest reductions in disturbance prediction uncertainty. 相似文献
544.
The National Vegetation Classification Standard (NVCS) was implemented at two US National Park Service (NPS) sites in Texas,
the Padre Island National Seashore (PINS) and the Lake Meredith National Recreation Area (LMNRA), to provide information for
NPS oil and gas management plans. Because NVCS landcover classifications did not exist for these two areas prior to this study,
we created landcover classes, through intensive ground and aerial reconnaissance, that characterized the general landscape
features and at the same time complied with NVCS guidelines. The created landcover classes were useful for the resource management
and were conducive to classification with optical remote sensing systems, such as the Landsat Thematic Mapper (TM). In the
LMNRA, topographic elevation data were added to the TM data to reduce confusion between cliff, high plains, and forest classes.
Classification accuracies (kappa statistics) of 89.9% (0.89) and 88.2% (0.87) in PINS and LMNRA, respectively, verified that
the two NPS landholdings were adequately mapped with TM data. Improved sensor systems with higher spectral and spatial resolutions
will ultimately refine the broad classes defined in this classification; however, the landcover classifications created in
this study have already provided valuable information for the management of both NPS lands. Habitat information provided by
the classifications has aided in the placement of inventory and monitoring plots, has assisted oil and gas operators by providing
information on sensitive habitats, and has allowed park managers to better use resources when fighting wildland fires and
in protecting visitors and the infrastructure of NPS lands. 相似文献
545.
Strange E Galbraith H Bickel S Mills D Beltman D Lipton J 《Environmental management》2002,29(2):290-300
The amount of ecological restoration required to mitigate or compensate for environmental injury or habitat loss is often
based on the goal of achieving ecological equivalence. However, few tools are available for estimating the extent of restoration
required to achieve habitat services equivalent to those that were lost. This paper describes habitat equivalency analysis
(HEA), a habitat-based “service-to-service” approach for determining the amount of restoration needed to compensate for natural
resource losses, and examines issues in its application in the case of salt marsh restoration. The scientific literature indicates
that although structural attributes such as vegetation may recover within a few years, there is often a significant lag in
the development of ecological processes such as nutrient cycling that are necessary for a fully functioning salt marsh. Moreover,
natural variation can make recovery trajectories difficult to define and predict for many habitat services. HEA is an excellent
tool for scaling restoration actions because it reflects this ecological variability and complexity. At the same time, practitioners
must recognize that conclusions about the amount of restoration needed to provide ecological services equivalent to those
that are lost will depend critically on the ecological data and assumptions that are used in the HEA calculation. 相似文献
546.
Fuzzy decision analysis for integrated environmental vulnerability assessment of the mid-Atlantic Region 总被引:20,自引:0,他引:20
Tran LT Knight CG O'Neill RV Smith ER Riitters KH Wickham J 《Environmental management》2002,29(6):845-859
A fuzzy decision analysis method for integrating ecological indicators was developed. This was a combination of a fuzzy ranking
method and the analytic hierarchy process (AHP). The method was capable of ranking ecosystems in terms of environmental conditions
and suggesting cumulative impacts across a large region. Using data on land cover, population, roads, streams, air pollution,
and topography of the Mid-Atlantic region, we were able to point out areas that were in relatively poor condition and/or vulnerable
to future deterioration. The method offered an easy and comprehensive way to combine the strengths of fuzzy set theory and
the AHP for ecological assessment. Furthermore, the suggested method can serve as a building block for the evaluation of environmental
policies. 相似文献
547.
Serveiss VB 《Environmental management》2002,29(2):145-154
Considerable progress in addressing point source (end of pipe) pollution problems has been made, but it is now recognized
that further substantial environmental improvements depend on controlling nonpoint source pollution. A watershed approach
is being used more frequently to address these problems because traditional regulatory approaches do not focus on nonpoint
sources. The watershed approach is organized around the guiding principles of partnerships, geographic focus, and management
based on sound science and data. This helps to focus efforts on the highest priority problems within hydrologically-defined
geographic areas. Ecological risk assessment is a process to collect, organize, analyze, and present scientific information
to improve decision making. The U.S. Environmental Protection Agency (EPA) sponsored three watershed assessments and found
that integrating the watershed approach with ecological risk assessment increases the use of environmental monitoring and
assessment data in decision making. This paper describes the basics of the watershed approach, the ecological risk assessment
process, and how these two frameworks can be integrated. The three major principles of watershed ecological risk assessment
found to be most useful for increasing the use of science in decision making are (1) using assessment endpoints and conceptual
models, (2) holding regular interactions between scientists and managers, and (3) developing a focus for multiple stressor
analysis. Examples are provided illustrating how these principles were implemented in these assessments. 相似文献
548.
California and other regions in the United States are becoming more populated and ethnically diverse, and thus, ecological
impacts on the wildland–urban interface are a significant policy concern. In a socioeconomic assessment focused on the geographic
regions surrounding four national forests in southern California, population projections are being formulated to assist in
the update of forest plans. In southern California, the projected trend of explosive population growth combined with increased
ethnic and racial diversity indicates four challenges for environmental management. First, patterns of recreation use on wildlands
are likely to change, and management of these areas will have to address new needs. Second, as land-management agencies face
changing constituencies, new methods of soliciting public involvement from ethnic and racial groups will be necessary. Third,
growth in the region is likely to encroach upon wildland areas, affecting water, air, open space, and endangered species.
Fourth, in order to address all these concerns in a climate of declining budgets, resource management agencies need to strengthen
collaborative relationships with other agencies in the region. How environmental managers approach these changes has widespread
implications for the ecological sustainability of forests in southern California. 相似文献
549.
Community involvement is fundamental to the management of multijurisdictional river basins but, in practice, is very difficult
to achieve. The Murray-Darling basin, in Australia, and the Mekong River basin in Southeast Asia are both cooperatively managed
multijurisdictional river basins where the management authorities have expressed an aim of community involvement. In the Murray-Darling
basin vigorous efforts have promoted a culture of community consultation throughout each of the state jurisdictions involved,
although true participation has not necessarily been achieved. In the Mekong basin the community is much more diverse and
the successes so far have been largely at the local level, involving action in subsections of the basin. These case studies
suggest that community involvement in the form of community consultation across large multijurisdictional river basins is
achievable, but more comprehensive participation is not necessarily possible. 相似文献
550.
分析探讨了浙江鄞县42级地震及历史上浙北中强震前的地震空区现象,认为孕震空区可能是浙北中等及中强震的中期前兆,并提出浙北孕震空区的特征及判别方法。 相似文献