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1.
Environmental Effects of Aquifer Overexploitation: A Case Study in the Highlands of Mexico 总被引:7,自引:0,他引:7
There are several environmental processes occurring under aquifer overexploitation conditions. These processes include groundwater
table decline, subsidence, attenuation and drying of springs, decrease of river flow, and increased pollution vulnerability,
among others processes. Some of these effects have been observed on the Upper Basin of the Lerma River. The Lerma River begins
in the SE of the Valley of Toluca at 2,600 m asl, in the wetland known as Lagoons of Almoloya del Río. This wetland is made
up of a group of lagoons, which are an important aquatic system from an environmental point of view. The water inflow of this
wetland is a discharge of springs, which occur between the fractured volcanic material of the mountain range and granular
volcanic–continental deposits of the Valley of Toluca aquifer. The intensive exploitation of the Valley of Toluca aquifer
to supply urban and industrial water to Mexico City and Toluca began in 1950 and is responsible for a steady decline of piezometric
levels of 1–3.5 m/yr. Other effects of this exploitation—the drying of the wetland, the decrease of river flow and the land
subsidence—caused serious ecological and social impacts. The authorities declared this aquifer as overexploited in order to
reduce the exploitation and preserve the availability of water resources in this important region. 相似文献
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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
4.
Synthetic Analysis for Extracting Information on Soil Salinity Using Remote Sensing and GIS: A Case Study of Yanggao Basin in China 总被引:4,自引:0,他引:4
Wanglu Peng 《Environmental management》1998,22(1):153-159
/ This paper reports the experience of extracting information on the salinity of soil and offers a method of synthetic analysis. The experimental areas for analysis are located in Yanggao Basin, Shanxi Province, China. The types of soil are mainly meadow soil and salinized meadow soil. The method of synthetic analysis of salinity uses a geographic information system (GIS) as a tool, building a basic saltwater analysis model of saline soil and adjusting the result with expert experience after computer processing. The method of feature extraction has been used for remotely sensed data. An optimum combination of features has been determined and, after comparing several combinations in the Yanggao region, an improved result has been obtained after Kauth-Thomas (K-T) transformation. For precise quantitative analysis of the salinization, not only Thematic Mapper (TM) remote sensing data, but also two forms of non-remote-sensing data are needed: depth of groundwater and mineralization rate of groundwater according to the theory of genesis of soil. For the analysis of synthetic compounded multisources, a generalized Bayes classification is used after overlay, matching, and related coefficients have been determined. On the premise that various information sources are independent, global membership functions with probability are used to combine various pieces of information in order to apply them directly to the pixels and classifications of soil salinity. The experiment indicates that this analytical method is sound because of the increased speed of processing and its simplicity and improved precision of classification of salinity. Finally, it is necessary to examine and adjust the factors using expert intelligence. The experiment shows that synthetic analysis using the geographic information system can raise the precision of quantitative analysis of salinity, which has advantages for environmental monitoring and management.KEY WORDS: Salinity; Remote sensing; Thematic Mapper; Geographic information system; Classification 相似文献
5.
Scientific information is not always effectively incorporated into decision-making processes. This phenomenon seems to hold
even when the information is aligned with an articulated need, is generated according to sound scientific procedures, and
is packaged with end-user preferences in mind. We propose that contextual or cultural differences contribute significantly
to the misalignment in communication between those who generate information and those who seek information for improved management
of natural resources. The solution is to cultivate shared understanding, which in turn relies on acknowledgment and sharing
of diverse values and attitudes. This constitutes a difficult challenge in a culturally diverse environment. Whereas cultural
diversity represents wealth in experiences, knowledge and perspectives it can constrain the potential to develop the shared
understandings necessary for effective integration of new information. This article illustrates how a lack of shared understanding
among participants engaged in a resource-management process can produce and perpetuate divergent views of the world, to the
extent that information and knowledge flows are ineffective and scientific information, even when requested, cannot be used
effectively. Four themes were distilled from interviews with management and scientific staff of a natural resource–management
agency in South Africa. The themes are used to illustrate how divergent views embedded in different cultures can discourage
alignment of effort toward a common purpose. The article then presents a sense-making framework to illustrate the potential
for developing shared understandings in a culturally diverse world. 相似文献
6.
The literature guides environmental planning and, specifically, how to use ecological rehabilitation projects to achieve long-term
planning goals and landscape-scale environmental sustainability. There is, however, a perceived gap between principles in
the literature and the use of them by practitioners involved in smaller-scale ecological rehabilitation projects. Using interviews
with practitioners involved in 11 projects within the Regional Municipality of Waterloo, Ontario, Canada, we tested whether
practitioners used five principles for effective planning and implementation of ecological rehabilitation that we derived
from the literature. These five principles were: establishing political and ecological context, using ecologically appropriate
objectives and practices, using comparative multidisciplinary and cross-scale approaches, using adaptive planning and implementation,
and establishing good communication within and external to projects. Few projects followed all five principles, and practitioners
indicated that they used three more project-specific principles: obtaining political/social support, promoting projects and
changing attitudes about projects, and securing sufficient and persistent funding to maintain a project's life. While the
literature emphasizes that ecological rehabilitation is only effective if projects are coordinated on a watershed basis, most
practitioners focused solely on the goals of their specific project. The gap between literature and practice may arise because
most practitioners are new to the field of ecological rehabilitation and still are focused on the methods involved. Time pressures
force practitioners to obviate the literature and get projects started quickly, lest support evaporate. Complicating these
difficulties is decreased support from federal and provincial governments for large-scale environmental planning. It is unclear
whether ecological rehabilitation projects in Waterloo Region (at least) will ever become effective at promoting landscape-scale
ecological goals or remain smaller-scale stop-gaps. 相似文献
7.
以松嫩盆地水资源开发利用现状为基础 ,以GIS软件 (地理信息系统 )MapInfoProfessional作为开发平台 ,设计和建立了松嫩盆地水资源开发管理信息系统。该系统的建立对松嫩盆地水资源开发管理状况和相关信息的查询、检索提供了方便 ,同时对松嫩盆地水资源的合理开发利用及其管理决策提供了科学依据。 相似文献
8.
Commercial Medicinal Plant Extraction in the Hills of Nepal: Local Management System and Ecological Sustainability 总被引:1,自引:0,他引:1
Helle Overgaard Larsen 《Environmental management》2002,29(1):88-101
This paper presents a case study from Jumla District, Nepal, investigating local management systems and ecological sustainability
of commercial collection of a medicinal plant, spikenard (Nardostachys grandiflora DC, Valerianaceae), growing in alpine meadows. Interviews were undertaken with local collectors, traders, and district forest
office staff, and the dynamics of people–plant interactions are analyzed using the Oakerson model. In all, 110 sample plots
1m square were laid out in three areas with differing collection and grazing pressures for recording of floristic composition
and abundance of spikenard root biomass. Comparisons show significantly more root biomass in uncollected than collected areas
with local management and the interpretation of differences in abundance is discussed. The combination of qualitative and
quantitative investigations can provide a framework for the study of people–plant interactions, and this study can serve as
first step in a compilation of cases to create a more detailed picture of local management systems of Nepali nontimber forest
products in general and commercially collected medicinal and aromatic plants in particular. 相似文献
9.
The Precautionary Principle: Scientific Uncertainty and Omitted Research in the Context of GMO Use and Release 总被引:3,自引:0,他引:3
Commercialization of genetically modified organisms (GMOs) have sparked profound controversies concerning adequate approaches to risk regulation. Scientific uncertainty and ambiguity, omitted research areas, and lack of basic knowledge crucial to risk assessmentshave become apparent. The objective of this article is to discuss the policy and practical implementation of the Precautionary Principle. A major conclusion is that the void in scientific understanding concerning risks posed by secondary effects and the complexity ofcause-effect relations warrant further research. Initiatives to approach the acceptance or rejection of a number of risk-associated hypotheses is badly needed. Further, since scientific advice plays a key role in GMOregulations, scientists have a responsibility to address and communicate uncertainty to policy makers and the public. Hence, the acceptance of uncertainty is not only a scientific issue, but is related to public policy and involves an ethical dimension. 相似文献
10.
Lloyd-Smith M 《Journal of environmental management》2009,90(4):1628-1635
In the environmental conflict that surrounds the sighting of hazardous waste facilities there is usually a volatile mix of disparities in power, expertise and information access as well as differing views on risk, which are all played out amidst commercial arrangements and environmental justice concerns. In recent times, the volatility of this mix has been further compounded by the growing climate of public concern and distrust surrounding scientific developments and technology. While there is no 'quick fix' to the complex conflict that this entails, community information systems (CISs) based on participatory models can help address the outstanding issues of capacity, information access, power inequities and environmental justice. CISs are an effective response to the five crucial elements of a toxic dispute, that is, the dialogue, capacity building, information access, evaluation of hazards and risk, and expertise. This paper will review the role of community accessible information systems in the dispute in Botany over the management and destruction of Orica Australia's stockpile of the persistent organic pollutant, hexachlorobenzene (HCB). It will focus on the role of CIS in responding to the challenges for expert information delivery, and in addressing the disparity of informational power within the toxic dispute. 相似文献