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631.
Nonpoint-Source Agricultural Hazard Index: A Case Study of the Province of Cremona, Italy 总被引:1,自引:0,他引:1
This paper reports the results of a study aimed at the evaluation of the hazard level of farming activities in the province
of Cremona, Italy, with particular reference to groundwater. The applied methodology employs a parametric approach based on
the definition of potential hazard indexes (nonpoint-source agricultural hazard indexes, NPSAHI). Two categories of parameters
were considered: the hazard factors (HF), which represent all farming activities that cause or might cause an impact on groundwater
(use of fertilizers and pesticides, application of livestock and poultry manure, food industry wastewater, and urban sludge),
and the control factors (CF), which adapt the hazard factor to the characteristics of the site (geographical location, slope,
agronomic practices, and type of irrigation). The hazard index (HI) can be calculated multiplying the hazard factors by the
control factors and, finally, the NPSAHI are obtained dividing HI into classes on a percentile basis using a scale ranging
from 1 to 10. Organization, processing, and display of all data layers were performed using the geographical information system
(GIS) ArcView and its Spatial Analyst extension. Results show that the potential hazard of groundwater pollution by farming
activities in the province of Cremona falls mainly in the fifth class (very low hazard). 相似文献
632.
BURGER J 《Environmental management》2000,26(5):469-478
With the ending of the Cold War, several federal agencies are reclaiming land through remediation and restoration and are
considering potential future land uses that are compatible with current uses and local needs. Some sites are sufficiently
contaminated that it is likely that the responsible federal agency will retain control over the land for the foreseeable future,
providing them with a stewardship mission. This is particularly true of some of the larger Department of Energy (DOE) facilities
contaminated during the production of nuclear weapons. The use of the term “restoration” is explored in this paper because
the word means different things to the public, ecologists, and environmental managers responsible for contaminated sites,
such as Superfund sites and the DOE facilities. While environmental restoration usually refers to remediation and removal
of hazardous wastes, ecological restoration refers to the broader process of repairing damaged ecosystems and enhancing their
productivity and/or biodiversity. The goals of the two types of restoration can be melded by considering environmental restoration
as a special case of ecological restoration, one that involves risk reduction from hazardous wastes, and by broadening environmental
restoration to include a more extensive problem-formulation phase (both temporal and spatial), which includes the goal of
reestablishing a functioning ecosystem after remediation. Further, evaluating options for the desired post remediation result
will inform managers and policy-makers concerning the feasibility and efficacy of environmental restoration itself. 相似文献
633.
Analysis of the character and condition of each river style in Bega catchment, and their downstream patterns, are used to
provide a biophysical basis to prioritorize river management strategies. These reach-scale strategies are prioritorized within
an integrative catchment framework. Conserving near-intact sections of the catchment is the first priority. Second, those
parts of the catchment that have natural recovery potential are targeted. Finally, rehabilitation priorities are considered
for highly degraded reaches. At these sites, erosion and sedimentation problems may reflect irreversible changes to river
structure. 相似文献
634.
/ The Itapiranga Sustainable Logging Plan provides an example of how Brazil's licensing system functions for logging companies in the state of Amazonas. Two questions need to be dealt with: "How sustainable can logging in the Amazon be?" and "What and how effective are existing legal mechanisms to deal with logging projects?" The environmental impact assessment (EIA) and environmental impact statement (EIS, known as the RIMA in Brazil), present relatively detailed accounts of biodiversity and the need to adopt conservation strategies to protect it. However, social and health impacts are only superficially addressed. The economic sustainability of the operation over multiple cycles is not demonstrated. The multidisciplinary teams responsible for the EIA and EIS (RIMA) reports are hired by the project proponent, an arrangement inherently carrying the risk of biasing the result. Logging reduces biodiversity, releases greenhouse gases and inflicts social and health costs. These impacts reduce the ability of Amazonian forests to provide environmental services and to supply food and livelihood security to local populations. The reports inflate positive effects such as employment: the estimated number of jobs was cut by more than half in a revision made after the EIA and EIS (RIMA) had been approved. Not only do the reports need to be more realistic in assessing both positive and negative consequences of proposed projects, but better means are needed to ensure that promised mitigatory measures are enforced in practice. Many of the lessons that can be drawn from the Itapiranga Plan are not unique to logging projects and apply to licensing of development activites generally in Brazil and elsewhere. 相似文献
635.
/ Fishes and their habitats were sampled in Harland Creek, Mississippi, for 3 years to compare the relative value of three types of bank treatment in an incised, warmwater stream. Semiannual samples were collected from 10 reaches: 3 reaches protected by each of the three types of protection (longitudinal stone toe, stone spurs, and dormant willow posts) and an unprotected, slowly eroding bend. Protection of concave banks of bends had no measurable effect on the habitat quality of downstream riffles. Although bends and adjacent downstream riffles were faunistically similar at the species level, catostomids and centrarchids were more dominant in pools and smaller cyprinids more dominant in riffles. Reaches with willow posts were slightly deeper than the others, most likely because of geomorphic factors rather than bank treatment. Mean water surface widths in reaches stabilized with stone spurs were 40% to 90% greater than for other treatments, and current velocities were greatest in reaches with stone toe. Patterns of fish abundance and species diversity did not differ significantly among treatments. However, principal components analysis indicated that the fish species distribution associated with the untreated reference site was distinct. Reaches stabilized with stone spurs supported significantly higher densities of large fish and higher levels of fish biomass per unit channel length than reaches with other bank treatments, generally confirming previous research in the region. Initial costs for spurs were comparable to those for stone toe and about three times greater than for willow posts. 相似文献
636.
/ Adaptive ecosystem management seeks to sustain ecosystems while extracting or using natural resources. The goal of endangered species management under the Endangered Species Act is limited to the protection and recovery of designated species, and the act takes precedence over other policies and regulations guiding ecosystem management. We present an example of conflict between endangered species and ecosystem management during the first planned flood on the Colorado River in Grand Canyon in 1996. We discuss the resolution of the conflict and the circumstances that allowed a solution to be reached. We recommend that adaptive management be implemented extensively and early in ecosystem management so that information and working relationships will be available to address conflicts as they arise. Though adaptive management is not a panacea, it offers the best opportunity for balanced solutions to competing management goals. 相似文献
637.
Mohammed M 《Environmental management》2000,25(2):177-188
/ This study aims to investigate the ISO 14001 implementation process and its implications for regional environmental management. The region of Central Japan (known as Chubu in Japanese, which literally means center) was chosen for this case study. The study focuses on selected issues such as the: (1) trends and motives of private firms in the implementation of an ISO 14001-based environmental management system (EMS); (2) obstacles during system implementation; (3) role of the system in enhancing environmental performance within the certified organization; and (4) relation between the major stakeholders, local citizens, governments, and firms after adopting the system. To achieve these objectives, a questionnaire survey was mailed to all certified firms in the region. A 58% response was achieved overall. The results show that the main aims behind the adoption of ISO 14001 by firms in the Chubu region are to improve the environmental aspects within the enterprises and to enhance the employees' environmental awareness and capacity. The results have also shown that the ISO 14001-based EMS has had a great effect on a firm's environmental status as certified firms have claimed that natural resources such as fuel, water, and paper consumption have been more efficiently managed after adopting the system. Implementation of the system causes the firms to consider the role of the local people and the government in more effectively involving the local people in the firm's daily environmental activities. It also helps to enhance the environmental awareness among the local people. Adopting the system also promotes a better relation within the enterprises affiliated to the same group, such as more attention given by the parent firms (head offices) towards other firms working for the same group, or branches-mainly small and medium sized enterprises (SMEs)-in the field of EMS. Finally, the results show that firms give serious consideration to their final products' impacts on the environment. In other words, attention is given to life cycle analysis (LCA) among certified firms. 相似文献
638.
sustainability, but the most meaningful definition is set within an evolutionary framework. Mechanistic and evolutionary frameworks for sustainable
development are discussed. Evolution and adaptation are characteristics of complex adaptive systems, and a new understanding
of sustainable development can be gleaned by using the complex adaptive systems framework. This approach to sustainable development
issues implicitly requires proactive involvement by the public. This paper supports that bottom-up participation needs to
be nurtured. Appropriate processes to enable participation need to be designed and implemented. 相似文献
639.
Chemical Characteristics of Urban Stormwater Sediments and Implications for Environmental Management, Maricopa County, Arizona 总被引:2,自引:0,他引:2
On the basis of published guidelines, urban stormwater sediments do not appear to constitute a major regional environmental
problem with respect to the chemical characteristics investigated here. At individual sites, high concentrations of organic
compounds—chlordane, dieldrin, PCBs, and toxaphene—may require some attention. The possible environmental hazard presented
by low-level organochlorine contamination is not addressed in this paper; however, high levels of toxicity in urban sediments
are difficult to explain. Sediment toxicity varied significantly with time, which indicates that these tests should be evaluated
carefully before they are used for management decisions. 相似文献
640.
5 –106 times higher compared with less sensitive species. The use of assessment factors in effect assessment procedures may lead
to an underestimation of effects on the more sensitive species.
For many priority pollutants there is little information on their ecotoxicity. Predictive techniques are needed to compensate
for this lack of data. Knowledge of the relation between modes of action of compounds and interspecies variation in sensitivity
should be integrated in risk assessment procedures in order to make more efficient use of the limited financial resources
available. 相似文献