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1.
Hydrologic modeling as a predictive basis for ecological restoration of salt marshes 总被引:4,自引:0,他引:4
Roads, bridges, causeways, impoundments, and dikes in the coastal zone often restrict tidal flow to salt marsh ecosystems.
A dike with tide control structures, located at the mouth of the Herring River salt marsh estuarine system (Wellfleet, Massachusetts)
since 1908, has effectively restricted tidal exchange, causing changes in marsh vegetation composition, degraded water quality,
and reduced abundance of fish and macroinvertebrate communities. Restoration of this estuary by reintroduction of tidal exchange
is a feasible management alternative. However, restoration efforts must proceed with caution as residential dwellings and
a golf course are located immediately adjacent to and in places within the tidal wetland. A numerical model was developed
to predict tide height levels for numerous alternative openings through the Herring River dike. Given these model predictions
and knowledge of elevations of flood-prone areas, it becomes possible to make responsible decisions regarding restoration.
Moreover, tidal flooding elevations relative to the wetland surface must be known to predict optimum conditions for ecological
recovery. The tide height model has a universal role, as demonstrated by successful application at a nearby salt marsh restoration
site in Provincetown, Massachusetts. Salt marsh restoration is a valuable management tool toward maintaining and enhancing
coastal zone habitat diversity. The tide height model presented in this paper will enable both scientists and resource professionals
to assign a degree of predictability when designing salt marsh restoration programs. 相似文献
2.
Developing a spatial framework of common ecological regions for the conterminous United States 总被引:4,自引:1,他引:4
McMahon G Gregonis SM Waltman SW Omernik JM Thorson TD Freeouf JA Rorick AH Keys JE 《Environmental management》2001,28(3):293-316
In 1996, nine federal agencies with mandates to inventory and manage the nation's land, water, and biological resources signed
a memorandum of understanding entitled “Developing a Spatial Framework of Ecological Units of The United States.” This spatial
framework is the basis for interagency coordination and collaboration in the development of ecosystem management strategies.
One of the objectives in this memorandum is the development of a map of common ecological regions for the conterminous United
States. The regions defined in the spatial framework will be areas within which biotic, abiotic, terrestrial, and aquatic
capacities and potentials are similar. The agencies agreed to begin by exploring areas of agreement and disagreement in three
federal natural-resource spatial frameworks—Major Land Resource Areas of the US Department of Agriculture (USDA) Natural Resources
Conservation Service, National Hierarchy of Ecological Units of the USDA Forest Service, and Level III Ecoregions of the US
Environmental Protection Agency. The explicit intention is that the framework will foster an ecological understanding of the
landscape, rather than an understanding based on a single resource, single discipline, or single agency perspective. This
paper describes the origin, capabilities, and limitations of three major federal agency frameworks and suggests why a common
ecological framework is desirable. The scientific and programmatic benefits of common ecological regions are described, and
a proposed process for development of the common framework is presented. 相似文献
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Agricultural land use can place heavy demands on regional water resources, strongly influencing the quantity and timing of water flows needed to sustain natural ecosystems. The effects of agricultural practices on streamflow conditions are multifaceted, as they also contribute to the severity of impacts arising from other stressors within the river ecosystem. Thus, river scientists need to determine the quantity of water required to sustain important aquatic ecosystem components and ecological services, to support wise apportionment of water for agricultural use. It is now apparent that arbitrarily defined minimum flows are inadequate for this task because the complex habitat requirements of the biota, which underpin the structure and function of a river ecosystem, are strongly influenced by predictable temporal variations in flow. We present an alternative framework for establishing a first-level, regional ecological instream flow needs standard based on adoption of the Indicators of Hydrologic Alteration/Range of Variability Approach as a broadly applicable hydrological assessment tool, coupling this to the Canadian Ecological Flow Index which assesses ecological responses to hydrological alteration. By explicitly incorporating a new field-based ecological assessment tool for small agricultural streams, we provide a necessary verification of altered hydrology that is broadly applicable within Canada and essential to ensure the continuous feedback between the application of flow management criteria and ecological condition. 相似文献
5.
A comprehensive action determination model: Toward a broader understanding of ecological behaviour using the example of travel mode choice 总被引:1,自引:0,他引:1
This paper examines a first version of a Comprehensive Action Determination Model (CADM) of ecological behaviour that incorporates intentional, normative, situational, and habitual influences on environmentally friendly behaviour. The main assumptions of the theory of planned behaviour (TPB), the norm-activation model (NAM), the theoretical concept of habit and the ipsative theory of behaviour were integrated into a comprehensive model. The model was tested using a structural equation modelling approach on a sample of 389 students in the domain of travel mode choice and compared to established less comprehensive models (TPB, NAM and a combination of both). The results show that all compared models had a good to excellent model fit and explained a substantial amount of variation in travel mode choice. The CADM, however, explained the greatest degree of variation as compared with the other models, at 65%. Subjective and objective situational constraints were responsible for most of the variation in travel mode choice in the CADM, but intentions and habits also had a significant impact. The influence of social and personal norms was mediated by habits and intention, while habits moderated the relationship between intention and behaviour. The importance of the CADM as a framework for other domains of ecological behaviour is also discussed. 相似文献
6.
Rail has an important role to play in the development toward a sustainable transportation system. In this perspective, the European Brite Euram Project RAVEL (Rail Vehicle Eco-Efficient Design) has developed a rail sectorwide Design for Environment system to be used and standardized throughout the full supply chain. At the core of the system, quantitative environmental performance indicators for rail vehicles and components are used to incorporate environmental performance target levels in the product requirements and to measure and communicate achieved environmental performance. The concept of eco-efficiency is used to integrate both environmental and economical considerations. The methodology further builds on a standardized material list, standardized data formats, and proactive design guidance. To date, first steps are already taken to integrate the RAVEL project results into sector initiatives toward industrywide acceptance and standardization.Published online
Note: This version was published online in June 2005 with the cover date of August 2004. 相似文献
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The capacity of duckweed to treat wastewater: ecological considerations for a sound design 总被引:1,自引:0,他引:1
Duckweed species are promising macrophytes for use in sustainable wastewater treatment due to their rapid growth, ease of harvest, and feed potential as a protein source. This paper reviews growth rates of different duckweed species on wastewater and ammonia toxicity to duckweed and summarizes insights into the mechanism of organic matter and nutrient removal. Results were gained from laboratory experiments in small, shallow, duckweed-covered semicontinuous batch systems. Growth rates on different types of wastewater vary considerably among different species. Ammonia is toxic for duckweed in both the ionized and un-ionized forms. Duckweed, however, can be used to treat wastewater containing very high total ammonia concentrations as long as certain pH levels are not exceeded. The degradation of organic material is enhanced by duckweed through both additional oxygen supply and additional surface for bacterial growth. The duckweed mat with attached bacteria and algae is, independent of the loading rates, responsible for three-quarters of the total nitrogen (N) and phosphorus (P) loss in very shallow systems. Based on our results we suggest that full-scale pilot plants with duckweed should be shallower than the range encountered in the literature. A harvesting schedule that allows doubling times of 2 to 3.5 d, maintenance of a full coverage, and plug flow conditions are recommended. 相似文献
10.
Farm management indicators and farm typologies as a basis for assessments in a changing policy environment 总被引:1,自引:0,他引:1
Andersen E Elbersen B Godeschalk F Verhoog D 《Journal of environmental management》2007,82(3):353-362
This paper focuses on the assessment of farm management indicators and argues that typologies are a necessary tool for comprehensive environmental assessments. In the paper Andersen et al., [(2004a). Farming and the Environment in the European Community--using agricultural statistics to provide farm management indicators. Paper presented at OECD Expert meeting, March 2004, New Zealand. < http:webdomino1.oecd.org/comnet/agr/farmind.nsf/viewHtml/index/$FILE/Anderson_et_al.PDF> (1st of February 2006).] presented at the OECD expert meeting on farm management indicators in New Zealand in March 2004, a set of farm management indicators was presented in the framework of a typology of grazing livestock farming systems in the EU-15 (includes all Member States of the European Union before 2004). The present paper presents new results on farm management indicators within the framework of an extended typology for all farming sectors. It presents an environmentally oriented extension to the EU typology of farms currently used for assessing the situation of farming within the European Union. The extended typology is tested in relation to emerging policy issues such as environmental sustainability and rural viability by analysing some of the farm management indicators suggested in Andersen et al., [(2004a). Farming and the Environment in the European Community--using agricultural statistics to provide farm management indicators. Paper presented at OECD Expert meeting, March 2004, New Zealand. (1st of February 2006).]. Finally, recommendations in relation to the next generation EU farm typology are given. 相似文献
11.
Chongrak Polprasert P.Y. Yang Noppadol Kongsricharoern Wilai Kanjanaprapin 《Resources, Conservation and Recycling》1994,11(1-4)
This paper presents a case study on pig farm waste management in which pig manure is stabilized in two-stage anaerobic reactors (to produce methane), while pig farm wastewater is treated in water hyacinth ponds from which the harvested water hyacinth plants are used in the production of silage (animal feed) or compost fertilizer. The results suggest the technical feasibility of applying these technologies to treat and recycle pig farm wastes. Cost/benefit analysis reveals the option to produce methane gas and silage to be financially viable after 15 years of operation. A management concept of waste recycling programs is presented, including relationships among objectives, constraints and implementation plan. Decision on a waste recycling program should not be based only on cost/benefit analysis, but also on the pollution control and public health improvement to be gained. 相似文献
12.
Kenneth A. Barrick 《Environmental management》2010,45(1):192-202
Geyser basins provide high value recreation, scientific, economic and national heritage benefits. Geysers are globally rare,
in part, because development activities have quenched about 260 of the natural endowment. Today, more than half of the world’s
remaining geysers are located in Yellowstone National Park, northwest Wyoming, USA. However, the hydrothermal reservoirs that
supply Yellowstone’s geysers extend well beyond the Park borders, and onto two “Known Geothermal Resource Areas”—Island Park
to the west and Corwin Springs on the north. Geysers are sensitive geologic features that are easily quenched by nearby geothermal
wells. Therefore, the potential for geothermal energy development adjacent to Yellowstone poses a threat to the sustainability
of about 500 geysers and 10,000 hydrothermal features. The purpose here is to propose that Yellowstone be protected by a “Geyser
Protection Area” (GPA) extending in a 120-km radius from Old Faithful Geyser. The GPA concept would prohibit geothermal and
large-scale groundwater wells, and thereby protect the water and heat supply of the hydrothermal reservoirs that support Yellowstone’s
geyser basins and important hot springs. Proactive federal leadership, including buyouts of private groundwater development
rights, can assist in navigating the GPA through the greater Yellowstone area’s “wicked” public policy environment. Moreover,
the potential impacts on geyser basins from intrusive research sampling techniques are considered in order to facilitate the
updating of national park research regulations to a precautionary standard. The GPA model can provide the basis for protecting
the world’s few remaining geyser basins. 相似文献
13.
B. Manos J. Papathanasiou Th. Bournaris K. Voudouris 《Journal of environmental management》2010,91(7):1593-1600
Current international research focuses on topics like sustainable development, regional planning, environmental decision making and implementation, biodiversity conservation plus a number of other relevant issues, especially at times of economic crisis as today. Economic growth and environmental protection can go hand in hand, provided that decision makers develop and use tools and insights targeting in the implementation of successful and robust long term policies. This paper was developed in the framework of a European research project and implements a Multicriteria Mathematical Programming model that optimises the sustainable management of agricultural regions taking in account the available resources (land, labour, capital) and environmental parameters (agrochemicals, water consumption). The model achieves the optimum farm plan in the area combining different criteria to a utility function under a set of constraints and the spatial integration of the vulnerability maps of the regions into the model enables the regional authorities to design policies for the optimal agricultural development and the groundwater protection from the agricultural land uses. Furthermore, the model is used to simulate different scenarios and policies by the local stakeholders, due to changes on different social, economic and environmental parameters. In this way the decision makers can achieve alternative farm plans and agricultural land uses as well as to estimate economic, social and environmental impacts of different policies. The model has been applied to an agricultural region in Northern Greece and proved to be a valuable tool in the implementation of environmental policies and actions, especially in agricultural regions in a delicate balance as the study area. 相似文献
14.
Thomas M. Bonnicksen 《Environmental management》1985,9(5):379-391
Initial decision analysis (IDA) is a microcomputer based decision-making technique that is organized so that a rational, step-by-step, procedure can be followed to use existing knowledge to develop resource policies. The IDA process provides a systematic way for participants to define their own problem and to explore jointly alternative solutions. IDA is particularly suited to resolving complex problems involving many groups with conflicting interests. IDA is illustrated with data from the US Forest Service's Draft Environmental Impact Statement for the 1985 to 2030 Resource Planning Act Program for the United States. Four policy options are evaluated: maximization of timber production, of grazing, and of wilderness, and a dominant use policy that concentrates timber management on productive sites. Policies were evaluated using a new mathematical satisficing procedure. Mathematical satisficing of simulated policy consequences showed that, for selected performance standards, current RPA policies are superior to the four alternative policies examined. 相似文献
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Landscape ecological assessment: a tool for integrating biodiversity issues in strategic environmental assessment and planning 总被引:11,自引:0,他引:11
To achieve a sustainable development, impacts on biodiversity of urbanisation, new infrastructure projects and other land use changes must be considered on landscape and regional scales. This requires that important decisions are made after a systematic evaluation of environmental impacts. Landscape ecology can provide a conceptual framework for the assessment of consequences of long-term development processes like urbanisation on biodiversity components, and for evaluating and visualising the impacts of alternative planning scenarios. The aim of this paper was to develop methods for integrating biodiversity issues in planning and strategic environmental assessment in an urbanising environment, on landscape and regional levels. In order to test developed methods, a case study was conducted in the region of Stockholm, the capital of Sweden, and the study area embraced the city centre, suburbs and peri-urban areas. Focal species were tested as indicators of habitat quality, quantity and connectivity in the landscape. Predictive modelling of habitat distribution in geographic information systems involved the modelling of focal species occurrences based on empirical data, incorporated in a landscape ecological decision support system. When habitat models were retrieved, they were applied on future planning scenarios in order to predict and assess the impacts on focal species. The scenario involving a diffuse exploitation pattern had the greatest negative impacts on the habitat networks of focal species. The scenarios with concentrated exploitation also had negative impacts, although they were possible to mitigate quite easily. The predictions of the impacts on habitats networks of focal species made it possible to quantify, integrate and visualise the effects of urbanisation scenarios on aspects of biodiversity on a landscape level. 相似文献
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Assessing the ecological security of the Tibetan plateau: methodology and a case study for Lhaze County 总被引:22,自引:0,他引:22
Zhao YZ Zou XY Cheng H Jia HK Wu YQ Wang GY Zhang CL Gao SY 《Journal of environmental management》2006,80(2):120-131
A system for assessing the ecological security of Lhaze County in China's Tibetan Autonomous Region was developed using a pressure-state-response model and the analytic hierarchy process. We then used this model to comprehensively evaluate the status of ecological security in Lhaze County. Our results showed that the ecological environment in Lhaze County has deteriorated from an 'early stages of damage status' in the 1980s to 'moderately damaged status' today. This deterioration has become a major barrier to local economic development and social advancement. Natural and social aspects related to the population explosion, resource exploitation, and climate change that led to this ecological deterioration are discussed. Furthermore, we have suggested proposals for improving the ecological environment that include controlling population growth and enhancing the system of laws that protect the environment, upgrading 3 882.6 ha of low-yield farmland, planting 2 425.8, 548.8, and 1 207.4 ha of shelter belts for farmland protection, soil and water conservation, and fuelwood, respectively, and seeding 2 358.1 ha of artificial grassland. In the meantime, we propose strengthening the controls that limit soil and water loss, and optimizing industrial sectors that aspire to achieve high-efficiency, ecologically responsible agriculture. 相似文献
19.
There has been increasing recognition within systematic conservation planning of the need to include social data alongside
biophysical assessments. However, in the approaches to identify potential conservation sites, there remains much room for
improvement in the treatment of social data. In particular, few rigorous methods to account for the diversity of less-easily
quantifiable social attributes that influence the implementation success of conservation sites (such as willingness to conserve)
have been developed. We use a case-study analysis of private conservation areas within the Little Karoo, South Africa, as
a practical example of the importance of incorporating social data into the process of selecting potential conservation sites
to improve their implementation likelihood. We draw on extensive data on the social attributes of our case study obtained
from a combination of survey questionnaires and semi-structured interviews. We discuss the need to determine the social attributes
that are important for achieving the chosen implementation strategy by offering four tested examples of important social attributes
in the Little Karoo: the willingness of landowners to take part in a stewardship arrangement, their willingness to conserve,
their capacity to conserve, and the social capital among private conservation area owners. We then discuss the process of
using an implementation likelihood ratio (derived from a combined measure of the social attributes) to assist the choice of
potential conservation sites. We conclude by summarizing our discussion into a simple conceptual framework for identifying
biophysically-valuable sites which possess a high likelihood that the desired implementation strategy will be realized on
them. 相似文献
20.
Mr E. O. Oriola 《The Environmentalist》1994,14(1):57-62
Summary Flooding has become an inherent problem in most urban centres close to the Nigerian coast. In the last decade it has extended to large settlements in the interior of the country where rainfall is more sporadic. This study has revealed that various socio-cultural activities have promoted flooding in many of these Nigerian urban environments. These activities are characterised by stream or river channel encroachment and abuse, increased paved surfaces and poor solid waste disposal techniques, due to a high level of illiteracy, a low degree of community awareness, poor environmental education, ineffective town planning laws and poor environmental management. Govenment, at various levels, needs to address these issues.His special field of interest is in natural resource management, focusing on the implications of environmental degradation and sustainable development. 相似文献