共查询到20条相似文献,搜索用时 15 毫秒
1.
Paul S. Addison John I. Currie David J. Low Joanna M. McCann 《Environmental monitoring and assessment》2000,65(1-2):333-342
An integrated method for the prediction of the spatial pollution distribution within a street canyon directly from a microscopic traffic simulation model is outlined. The traffic simulation package Paramics is used to model the flow of vehicles in realistic traffic conditions on a real road network. This produces details of the amount of pollutant produced by each vehicle at any given time. The authors calculate the dispersion of the pollutant using a particle tracking diffusion method which is superimposed on a known velocity and turbulence field. This paper shows how these individual components may be integrated to provide a practical street canyon pollution model. The resulting street canyon pollution model provides isoconcentrations of pollutant within the road topography. 相似文献
2.
Clements A 《Environmental monitoring and assessment》2004,99(1-3):233-243
Desertification of shrub and grassland into pinyon-juniper woodland is occurring over much of the Colorado Plateau in the
southwestern United States. As trees invade, they out-compete shrubs and grasses, increasing erosion rates and reducing infiltration
of moisture into the soil. This has caused habitat problems for wildlife, and reduced forage for livestock. These impacts
also affect the human communities that rely on ranching and tourism related to hunting. Past land use and management practices
including heavy livestock grazing, fire suppression and introduction of exotic annual plants are believed to have led to current
conditions. The Montrose office of the Bureau of Land Management has implemented an ecosystem-based program to reverse the
desertification process on public land. The program is centered on detailed landscape objectives describing the desired vegetation
mosaic on 360 000 ha of public land. The objectives outline proportions of plant seral stages and arrays of patch sizes for
each planning unit. These objectives are based on priority management issues and the need to replicate a natural vegetation
mosaic. Where the existing mosaic does not meet objectives, mechanical vegetation treatments and prescribed fire are used
to create early and mid-seral patches on the ground. This restored vegetation pattern and type should be sustained over time
through a natural fire regime and improved livestock management. Because many uncertainties exist, an adaptive management
process is being used that allows mosaic objectives to be changed or processes modified where monitoring or scientific research
indicate a need. 相似文献
3.
Boris Agarski Igor Budak Borut Kosec Janko Hodolic 《Environmental Modeling and Assessment》2012,17(3):255-266
In the domain of environmental protection, multi-criteria evaluation is used in cases where multiple alternatives, on the
bases of multiple parameters, need to be evaluated. Depending on the particular goal of investigation, various approaches
have been developed and applied. This various multi-criteria approaches differ in parameter weighting method, in data normalization
method as well as in the method for assessment of alternatives. According to the applied multi-criteria methodology, the result,
i.e., the rank of alternatives may differ to some extent. In this context, parameter weighting bears special significance
in multi-criteria evaluation, while the choice of method is crucial for final result. The specificity of parameter weighting
process in environment protection is directly related to pronounced interdisciplinary character of this area, as well as the
large number of influential parameters. With this in mind, this paper presents an approach to multi-criteria evaluation which—through
integration of three specific methods for parameter weighting—allows more flexible and multi-purpose application. Based on
the established concept, a software application was developed. Besides automated parameter weighting, it also provides graphical
interpretation of results. The developed approach and software have been verified on the case study related to evaluation
of environmental loadings at six locations in the city of Novi Sad. 相似文献
4.
An Analytical Solution to Model Aquaculture Wetlands Subject to Intermittent Loading and Variable Initial Concentrations 总被引:1,自引:0,他引:1
Venkatesh Uddameri 《Environmental Modeling and Assessment》2010,15(1):27-35
Constructed wetlands are increasingly being used to treat intermittent releases of wastewaters from aquaculture ponds. Most
constructed wetland design protocols are based on steady-state releases and as such are incapable of characterizing transient
pollutant distribution arising from intermittent releases. Given the seasonal nature of aquaculture operations, the constructed
wetland has to be developed using water from other nearby sources (termed as fill water in this study). In some instances,
the pollutant concentrations in the fill water are noted to be greater than that measured in the aquaculture ponds. Also,
the pollutants in the wetland may exhibit spatial variability due to geochemical interactions with wetland soils. These effects
cannot be captured with existing steady-state design schemes. A mathematical model based on the tanks-in-series conceptualization
is developed to overcome the aforementioned limitations. An analytical solution for multiple intermittent releases and spatially
varying initial concentrations is obtained using Laplace transform and superposition techniques. The utility of the developed
model is illustrated using an example based after a constructed wetland at the Loma Alta Shrimp Aquaculture Facility (LASAF)
in South Texas. The developed model captures the extremely nonlinear relationship between the maximum discharge concentration
and the hydraulic residence time. For the conditions assumed in this study, the extent of mixing is not of major concern when
the spacing between the loadings is greater than 0.75 times the hydraulic residence time (HRT). Model results also suggest
that the wetland should be oriented in a manner such that the internal geochemical production of the pollutant, if any, is
near the inlet. 相似文献
5.
6.
Irving Schiffman 《Environmental Impact Assessment Review》1985,5(2):183-193
Despite obstacles inherent in the structure of government and the lack of a strong national constituency, environmental impact assessment became a policy-making element in the government of Israel in 1982. The Environmental Protection Service formed in 1973 now needs to develop strategies to promote environmental awareness and environmentally informed decision making among the public, private and public developers, and within the Ministry of the Interior. 相似文献
7.
Desertification in some form is estimated to have occurred over about 42% of the 5 million km2 of arid and semiarid lands in Australia. The most common form of desertification is loss of perennial grasses from grasslands, savannas, and open woodlands, often with a replacement by inedible shrubs. Desertification continues to be a problem, especially during droughts when grazing pressures reduce ground cover, laying bare landscapes to wind and water erosion. But two national programs, Drought Alert and Landcare, are giving new hope in controlling land degradation. Both use a grassroots approach by promoting action through local pastoralist and farmer groups and by encouraging the use of effective techniques for rehabilitating landscapes. A strategic application of ponding banks and contour traps with an eye to the landscape has proven successful in stopping and reversing desertification processes. 相似文献
8.
Dobson J Gardner M Miller B Jessep M Toft R 《Journal of environmental monitoring : JEM》1999,1(1):91-95
This paper reports an approach to the assessment of the validity of environmental monitoring data--a 'data filter'. The strategy has been developed through the UK National Marine Analytical Quality Control (AQC) Scheme for application to data collected for the UK National Marine Monitoring Plan, although the principles described are applicable more widely. The proposed data filter is divided into three components: Part A, 'QA/QC'--an assessment of the laboratory's practices in Quality Assurance/Quality Control; Part B, 'fitness for purpose'--an evaluation of the standard of accuracy that can be demonstrated by activities in (A), in relation to the intended application of the data; and Part C, the overall assessment on which data will be accepted as usable or rejected as being of suspect quality. A pilot application of the proposed approach is reported. The approach described in this paper is intended to formalise the assessment of environmental monitoring data for fitness for a chosen purpose. The issues important to fitness for purpose are discussed and assigned a relative priority order on which to judge the reliability/usefulness of monitoring data. 相似文献
9.
An Approach to Reaeration Coefficient Modeling in Local Surface Water Quality Monitoring 总被引:1,自引:0,他引:1
Reaeration coefficient (k 2) for River Atuwara, Ogun State, Nigeria was calculated from dissolved oxygen and biochemical oxygen demand data collected over period of 3 months covering the two prevailing climatic seasons in the country. Both the Akaike and Bayesian information criteria were used in the selection and analysis of ten models to identify the most suitable reaeration coefficient (k 2) model for Atuwara River. Models that passed the confidence limit were subjected to model evaluation using measures of agreement between observed and predicted data such as percent bias, Nash–Sutcliffe efficiency, and root mean square observation standard deviation ratio. The used approach yield better results than empirical models developed for local conditions while it is also useful in conserving scarce resources. 相似文献
10.
11.
Giovanna Finzi Alberto Novo Silvio Viarengo 《Environmental monitoring and assessment》1991,17(2-3):273-280
This paper presents the preliminary results of a study, the aim of which was to analyse the pluviometric and chemical rain data, recorded by a wet only network located in Northern Italy.More in detail, precipitations were collected on a weekly basis and chemical analysis was performed on pH, electric conductivity and Ca, Mg, Na, K, NH4, NO3, SO4, Cl concentrations.The Principal Components Analysis pointed out that the first three components are enough to explain more than 90% of the variability of the parameters. Moreover each component may have a different physical interpretation, that is the first one is mainly related to the precipitation amount, while the second to the man made and natural sources and the last one to the sea/soil contribution. 相似文献
12.
The integration of knowledge from stakeholders and the public at large is seen as one of the biggest process-related barriers during the scoping phase of EIA application in transport planning. While the academic literature offers abundant analyses, discussions and suggestions how to overcome this problem, the proposed solutions are yet to be adequately tested in practice. In order to address this gap, we test the effectiveness of a set of interventions and trigger mechanisms for improving different aspects of knowledge integration. The interventions are tested in an experiential study with two sequential cases, representing “close-to-real-life” conditions, in the context of two cities in Andalusia, Spain. In general terms, the participants perceived that the integration of knowledge improved during the simulation of the EIA scoping phase. Certain shortcomings were also discussed, fundamentally related to how the time spent during the scoping phase was crucial to lead an effective learning process between the involved people. The study concludes with a reflection on the effectiveness of the tested interventions according to similarities and differences obtained from the two experiential case studies, as well as with a discussion of the potential to generate new knowledge through the use of experiential studies in EIA practice. 相似文献
13.
14.
Broder Breckling Hauke Reuter Ulrike Middelhoff 《Environmental Modeling and Assessment》1997,2(1-2):95-104
The object oriented programming and simulation approach has been used at the Project Center for Ecosystems Research (Kiel) in order to advance ecological theory and in order to integrate empirical ecological field work. In this contribution we present a general scheme, which provides a framework for the development of individual based models. The scheme covers a general layout of the organism – environment interaction; the organization of (quasi‐)parallel activities of individuals (self‐scheduling of objects versus list processing); a concept to coordinate context specific activity alternatives. Basing on these considerations we give different application examples. These examples show the potential of individual based modelling to depict the modification of organismic activity pattern and population dynamics in heterogeneous environments and to study the interaction of different levels of aggregation. The model examples are simulation of a fish school in a changing environment; simulation of a robin population in a beech forest; simulation of plant development. 相似文献
15.
Christian Condevaux‐Lanloy Emmanuel Fragnière 《Environmental Modeling and Assessment》2000,5(3):145-155
This paper presents a new concept to include uncertainty management in energy and environmental planning models developed in algebraic modeling languages. SETSTOCH is a tool for linking algebraic modeling languages with specialized stochastic programming solvers. Its main role is to retrieve from the modeling language a dynamically ordered core model (baseline scenario) that is sent automatically to the stochastic solver. The case presented herein concerns such a study realized with the IEAMARKAL model used by many research teams around the world. 相似文献
16.
Robert K. Hall David Guiliano Sherman Swanson Michael J. Philbin John Lin Joan L. Aron Robin J. Schafer Daniel T. Heggem 《Environmental monitoring and assessment》2014,186(4):2413-2433
Prioritizing total maximum daily load (TMDL) development starts by considering the scope and severity of water pollution and risks to public health and aquatic life. Methodology using quantitative assessments of in-stream water quality is appropriate and effective for point source (PS) dominated discharge, but less so in watersheds with mostly nonpoint source (NPS) related impairments. For NPSs, prioritization in TMDL development and implementation of associated best management practices should focus on restoration of ecosystem physical functions, including how restoration effectiveness depends on design, maintenance and placement within the watershed. To refine the approach to TMDL development, regulators and stakeholders must first ask if the watershed, or ecosystem, is at risk of losing riparian or other ecologically based physical attributes and processes. If so, the next step is an assessment of the spatial arrangement of functionality with a focus on the at-risk areas that could be lost, or could, with some help, regain functions. Evaluating stream and wetland riparian function has advantages over the traditional means of water quality and biological assessments for NPS TMDL development. Understanding how an ecosystem functions enables stakeholders and regulators to determine the severity of problem(s), identify source(s) of impairment, and predict and avoid a decline in water quality. The Upper Reese River, Nevada, provides an example of water quality impairment caused by NPS pollution. In this river basin, stream and wetland riparian proper functioning condition (PFC) protocol, water quality data, and remote sensing imagery were used to identify sediment sources, transport, distribution, and its impact on water quality and aquatic resources. This study found that assessments of ecological function could be used to generate leading (early) indicators of water quality degradation for targeting pollution control measures, while traditional in-stream water quality monitoring lagged in response to the deterioration in ecological functions. 相似文献
17.
运用方差分析法分析白城市月亮湖水库水质 总被引:2,自引:0,他引:2
运用方差分析法中的相关系数法和SNK检验方法,分析了1998~2007年白城月亮湖水库中主要污染物的监测数据.结果显示,溶解氧与氨氮具有线性关系,与高锰酸盐指数正相关,pH值在10年中没有显著变化. 相似文献
18.
An expert-based approach to forest road network planning by combining Delphi and spatial multi-criteria evaluation 总被引:1,自引:0,他引:1
Elyas Hayati Baris Majnounian Ehsan Abdi John Sessions Majid Makhdoum 《Environmental monitoring and assessment》2013,185(2):1767-1776
Changes in forest landscapes resulting from road construction have increased remarkably in the last few years. On the other hand, the sustainable management of forest resources can only be achieved through a well-organized road network. In order to minimize the environmental impacts of forest roads, forest road managers must design the road network efficiently and environmentally as well. Efficient planning methodologies can assist forest road managers in considering the technical, economic, and environmental factors that affect forest road planning. This paper describes a three-stage methodology using the Delphi method for selecting the important criteria, the Analytic Hierarchy Process for obtaining the relative importance of the criteria, and finally, a spatial multi-criteria evaluation in a geographic information system (GIS) environment for identifying the lowest-impact road network alternative. Results of the Delphi method revealed that ground slope, lithology, distance from stream network, distance from faults, landslide susceptibility, erosion susceptibility, geology, and soil texture are the most important criteria for forest road planning in the study area. The suitability map for road planning was then obtained by combining the fuzzy map layers of these criteria with respect to their weights. Nine road network alternatives were designed using PEGGER, an ArcView GIS extension, and finally, their values were extracted from the suitability map. Results showed that the methodology was useful for identifying road that met environmental and cost considerations. Based on this work, we suggest future work in forest road planning using multi-criteria evaluation and decision making be considered in other regions and that the road planning criteria identified in this study may be useful. 相似文献
19.
Boonsatien Boonsoong Narumon Sangpradub Michael T. Barbour Wijarn Simachaya 《Environmental monitoring and assessment》2010,161(1-4):205-215
The present study showed a possibility to use phenotypic and proteomic responses in rice plants as an in vivo biomarker to detect higher concentrations of ambient ozone (O3). The investigation was done on two cultivars of Indian rice using open top chambers ventilated with charcoal filtered air, ambient air, ambient air with 10 ppb O3 exposure and ambient air with 20 ppb O3 exposure at a rural site of Varanasi, India. Results showed that the magnitude of O3 induced specific type of foliar injury directly depends on the duration and concentration of O3 exposure. Even the internal protein profile of injured and normal leaf demonstrated a differential expression, which directly indicates towards the molecular basis of plant’s response against O3. 相似文献
20.
Anastasios Xepapadeas 《Environmental Modeling and Assessment》1996,1(1-2):25-35
A quantity-quality problem in which pollution generates production externalities is analyzed empirically. Water is pumped by farmers from a common access aquifer, and deep percolation resulting from the irrigation causes accumulation of pollutants in the aquifer. Pollution negatively affects the production of the agricultural output through the deterioration of the groundwater quality. By comparing the cooperative with the noncooperative solution, an optimal policy scheme in the form of water taxes is determined. The scheme induces farmers acting noncooperatively to follow policies that correspond to the regulator's optimum. The model is applied to the case of groundwater management in the Iraklio prefecture of Crete. Agricultural production functions are estimated using an externality variable as explanatory variable. An optimal control model that corresponds to the cooperative solution is solved using multiple shooting methods. Paths for water stock, salinity stock, and water use at the regulator's optimum are derived. The optimal water tax is calculated in the final stage. 相似文献