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1.
The Groundwater Protection Project at the US Department of Energy Hanford Site in Washington State is currently developing the means to assess the cumulative impact to human and ecological health and the regional economy and cultures from radioactive and chemical waste that will remain at the Hanford Site after the site closes. This integrated system is known as the System Assessment Capability (SAC). The SAC Risk/Impact Module discussed in the article uses media- and time-specific concentrations of contaminants estimated by the transport models of the integrated system to project potential impacts on the ecology of the Columbia River corridor, the health of persons who might live in or use the corridor or the upland Hanford environment, the local economy, and cultural resources. Preliminary Monte Carlo realizations from the SAC modeling system demonstrate the feasibility of large-scale uncertainty analysis of the complex relationships in the environmental transport of contaminants on the one hand and ecological, human, cultural, and economic risk on the other. Initial impact results show very small long-term risks for the 10 radionuclides and chemicals evaluated. The analysis also helps determine science priorities to reduce uncertainty and suggests what actions matter to reduce risks.  相似文献   

2.
Probability distributions that model the return periods of flood characteristics derived from partial duration series are proposed and tested in the Fraser River catchment of British Columbia. Theoretical distributions describing the magnitude, duration, frequency and timing of floods are found to provide a goof fit to the observed data. The five estimated parameters summarizing the flood characteristics of each basin are entered into a discriminant analysis procedure to establish flood regions. Three regions were identified, each displaying flood behavior closely related to the physical conditions of the catchment. Within each region, regression equations are obtained between parameter values and basin climatic and physiographic variables. These equations provide a satisfactory prediction of flood parameters and this allows the estimation of a comprehensive set of flood characteristics for areas with sparse hydrologic information.  相似文献   

3.
ABSTRACT: The ability of regulators, resource managers, and consultants to assess accurately wetland hydrology is crucial when identifying and delineating wetlands. In this study, simple linear regression and long‐term (ten year) New Jersey Pinelands stream gaging and pitch pine lowland water‐level data sets were used to estimate long‐term hydroperiods at lowland test sites with short‐term (two year) records. Separate regression equations were developed for each test site using reference site data and stream gaging data, and two sets of equations for selected test sites were produced using two different short‐term periods of record. Test sites had long‐term records ranging from four to ten years, allowing validation of the regression models. Measured and predicted test site growing season water levels were similar regardless of which short‐term period of record was used. The results based on the stream gaging site data were similar, although the difference between measured and estimated growing season water levels was greater when this approach was used. Excellent agreement was found between measured and estimated frequencies of near‐surface saturation at test sites for each growing season month, and these relationships improved when cumulative, seasonal frequencies were considered. The reference wetland approach used in this study may have its greatest value in regions with both high development pressures and problem wetlands and may provide an effective way of resolving costly wetland delineation disputes.  相似文献   

4.
Coastal catchments in British Columbia, Canada, experience a complex mixture of rainfall‐ and snowmelt‐driven contributions to flood events. Few operational flood‐forecast models are available in the region. Here, we integrated a number of proven technologies in a novel way to produce a super‐ensemble forecast system for the Englishman River, a flood‐prone stream on Vancouver Island. This three‐day‐ahead modeling system utilizes up to 42 numerical weather prediction model outputs from the North American Ensemble Forecast System, combined with six artificial neural network‐based streamflow models representing various slightly different system conceptualizations, all of which were trained exclusively on historical high‐flow data. As such, the system combines relatively low model development times and costs with the generation of fully probabilistic forecasts reflecting uncertainty in the simulation of both atmospheric and terrestrial hydrologic dynamics. Results from operational testing by British Columbia's flood forecasting agency during the 2013‐2014 storm season suggest that the prediction system is operationally useful and robust.  相似文献   

5.
Site selection is a key activity for quarry expansion to support cement production, and is governed by factors such as resource availability, logistics, costs, and socio-economic-environmental factors. Adequate consideration of all the factors facilitates both industrial productivity and sustainable economic growth. This study illustrates the site selection process that was undertaken for the expansion of limestone quarry operations to support cement production in Barbados. First, alternate sites with adequate resources to support a 25-year development horizon were identified. Second, technical and socio-economic-environmental factors were then identified. Third, a database was developed for each site with respect to each factor. Fourth, a hierarchical model in analytic hierarchy process (AHP) framework was then developed. Fifth, the relative ranking of the alternate sites was then derived through pair wise comparison in all the levels and through subsequent synthesizing of the results across the hierarchy through computer software (Expert Choice). The study reveals that an integrated framework using the AHP can help select a site for the quarry expansion project in Barbados.  相似文献   

6.
Spackman Jones, Amber, David K. Stevens, Jeffery S. Horsburgh, and Nancy O. Mesner, 2010. Surrogate Measures for Providing High Frequency Estimates of Total Suspended Solids and Total Phosphorus Concentrations. Journal of the American Water Resources Association (JAWRA) 1‐15. DOI: 10.1111/j.1752‐1688.2010.00505.x Abstract: Surrogate measures like turbidity, which can be observed with high frequency in situ, have potential for generating high frequency estimates of total suspended solids (TSS) and total phosphorus (TP) concentrations. In the semiarid, snowmelt‐driven, and irrigation‐regulated Little Bear River watershed of northern Utah, high frequency in situ water quality measurements were recorded in conjunction with periodic chemistry sampling. Site‐specific relationships were developed using turbidity as a surrogate for TP and TSS at two monitoring locations. Methods are presented for employing censored data and for investigating categorical explanatory variables (e.g., hydrologic conditions). Turbidity was a significant explanatory variable for TP and TSS at both sites, which differ in hydrologic and water quality characteristics. The relationship between turbidity and TP was stronger at the upper watershed site where TP is predominantly particulate. At both sites, the relationships between turbidity and TP varied between spring snowmelt and base flow conditions while the relationships between TSS and turbidity were consistent across hydrological conditions. This approach enables the calculation of high frequency time series of TP and TSS concentrations previously unavailable using traditional monitoring approaches. These methods have broad application for situations that require accurate characterization of fluxes of these constituents over a range of hydrologic conditions.  相似文献   

7.
Regression models of mean and mean annual maximum (MAM) cover were derived for two categories of periphyton cover (filaments and mats) using 22 years of monthly monitoring data from 78 river sites across New Zealand. Explanatory variables were derived from observations of water quality variables, hydrology, shade, bed sediment grain size, temperature, and solar radiation. The root mean square errors of these models were large (75‐95% of the mean of the estimated values). The at‐site frequency distributions of periphyton cover were approximated by the exponential distribution, which has the mean cover as its single parameter. Independent predictions of cover distributions at all sites were calculated using the mean predicted by the regression model and the theoretical exponential distribution. The probability that cover exceeds specified thresholds and estimates of MAM cover, based on the predicted distributions, had large uncertainties (~80‐100%) at the site scale. However, predictions aggregated by classes of an environmental classification accurately predicted the proportion of sites for which cover exceeded nominated criteria in the classes. The models are useful for assessing broad‐scale patterns in periphyton cover and for estimating changes in cover with changes in nutrients, hydrological regime, and light.  相似文献   

8.
A method of predicting probability distributions of annual floods is presented and is applied to the Fraser River catchment of British Columbia. The Gumbel distribution is found to adequately describe the observed flood frequency data. Using the estimated Gumbel parameters, discriminant analysis is performed to separate basins into flood regions. Within each region, regression analysis is used to relate physiographic and climatic variables to the means and standard deviations of the annual flood series. The regression equations are applied to four test basins and the results indicate that the method is suitable for an estimation of annual floods.  相似文献   

9.
Soils of riparian wetlands are highly effective at phosphorus (P) sorption. However, these soils exhibit extreme spatial variability across riparian zones. We used a spatially explicit sampling design in two riparian wetlands in North Carolina to better understand the relationships among P sorption, soil properties, and spatial variability. Our objectives were to quantify patterns of spatial variability of P sorption and related soil properties, and to determine which soil properties best explained the variability in P sorption after accounting for the effects of spatial autocorrelation. We measured bulk density, moisture, pH, soil organic matter (SOM), texture (percent clay, silt, and sand), oxalate-extractable aluminum (Al(ox)), iron (Fe(ox)), and the phosphorus sorption index (PSI). Due to differences in texture, Al(ox), and Fe(ox), the two sites had substantially different mean PSIs. At each site, we found considerable differences in the spatial variability of soil properties. For example, semivariance analysis and kriging illustrated that soil properties at Site 1 varied at smaller scales than those at Site 2. At both sites, after accounting for the effects of spatial autocorrelation and all other soil properties, we determined that Al(ox) had the highest Mantel correlation with PSI. We believe this geostatistic and Mantel approach is robust and could serve as a model for research on other biogeochemical processes such as denitrification.  相似文献   

10.
3 are damaged annually by snow and wind, roughly corresponding to a value of US$150 million, and in Europe, the damage amounts to hundreds of millions of US dollars each year. To help to reduce these losses, tools for risk assessment within forest management have been developed. Predictions were developed of the risk of damage from snow and wind to Scots pine (Pinus sylvestris L.), Norway spruce [Picea abies (L.) Karst.] and Birch (Betula spp. L.) plots using tree, stand, and site characteristics. The data were obtained from 6756 permanent sample plots within the Swedish National Forest Inventory, which were inventoried twice at five-year intervals between 1983 and 1992. Input data for model development used measurements from the first inventory of tree characteristics for the largest sample tree, stand, and site data, and records of snow and wind damage from the second inventory. Models were developed for three different regions for pine- and spruce-dominated sites, while models for the whole country were developed for birch sites. In general the estimated proportion of damaged plots was highly overestimated (31.7%–56.2%), compared with the observed proportion of 3.4%–11.9%. The models for Norway spruce comprising tree, stand, and site data show the best predictability of damaged plots, with 60.6%–67.6% of plots correctly classified. It is concluded that the models developed can be used to detect sites with a high probability of damage from snow and wind, and thus be used as tools to reduce future damage and costs in practical forestry.  相似文献   

11.
ABSTRACT: Bank full hydraulic geometry relationships relate stream channel geometry to watershed size for specific physiographic regions. This paper presents bank full hydraulic geometry relationships and recurrence intervals for the Southeastern Plain coercion and the flat woods subtype of the Middle Atlantic Coastal Plain ecoregion found within North Carolina's Coastal Plain physiographic province. Cross‐sectional and longitudinal survey data from gated and unpaged streams were used to compute channel dimension and profile information. Power functions were developed, relating drainage area to bank full discharge, cross‐sectional area, width, and mean depth. Recurrence intervals of bank full events were estimated from gagged streams using both a Log‐Pearson Type III distribution of peak annual discharge and a partial‐duration series of average daily discharge. Results from both methods indicate that average bank full recurrence intervals for the study area are below one year. Determinations of recurrence intervals by the Log‐Pearson Type III distribution were for the most part inconclusive (less than one year), while a partial duration series estimated a 0.19 year average, ranging from 0.11 to 0.31 years.  相似文献   

12.
Riparian Zone Management in the Pacific Northwest: Who's Cutting What?   总被引:2,自引:0,他引:2  
Oncorhynchus sp.), regional governments now restrict timber harvest in riparian forests. I summarize and assess the riparian zone management guidelines of the states of California, Oregon, and Washington (USA) and the province of British Columbia (Canada). Only Oregon and British Columbia protect fish-bearing streams with “no-harvest” zones, and only the wider (20–50 m) no-harvest zones for larger fish-bearing streams in British Columbia are likely to maintain near-natural linkages between riparian and stream ecosystems. All four jurisdictions protect most streams with “management zones” of variable width, in which timber harvest activities are restricted. All the management zone guidelines permit the harvest of the largest conifers from riparian forests and will, if applied over a series of timber harvest rotations (60–80 years), result in the continued removal of potential sources of large woody debris from the region's watersheds. All four jurisdictions require additional protection for streams and watersheds that are severely degraded or (in the United States) contain threatened or endangered species. The governments of the PNW have taken a “manage until degraded, then protect” approach to riparian forest management that is unlikely to maintain or restore the full suite of riparian-stream linkages necessary for lotic ecosystems to function naturally at the stream, watershed, basin, or regional scale.  相似文献   

13.
This paper reports the results of a comparative analysis of the psychosocial impacts of municipal solid waste disposal facilities (both landfills and incinerators) in six communities in the provinces of Ontario and British Columbia, Canada. Telephone surveys were administered to random samples of residents living around each facility between 1990 and 1995 (total n=1203). The results of logistic regression analyses show that type of facility was the strongest predictor of residents' awareness, concern, and actions taken in response to site concerns. Essentially, residents living in close proximity to a landfill had a higher probability of reporting awareness, concern or actions than residents living around an incinerator site. There was little evidence of differences in reactions between Ontario and British Columbia (BC) residents, despite variations in provincial policies on waste disposal. The effects of other predictors, with the exception of involvement in the local community, were not consistent, supporting previous findings that the determinants of facility impacts are outcome‐specific. It is essential that environmental managers take this constellation of factors into account in the operation of existing, or siting of new, facilities.  相似文献   

14.
This study examines the effects of acidifying sulphur emissions on freshwater ecosystems in the traditional territory of Treaty 8 First Nations in British Columbia (BC). Due to the absence of detailed water chemistry data for most lakes in the region, revised empirical methods for estimating freshwater sensitivity to acidification are formulated using linear regression relationships between individual chemical measurements, and critical loads of acidity calculated using the Steady State Water Chemistry (SSWC) model. Lake alkalinity is the most effective chemical indicator of acidification sensitivity in northeast BC. Critical loads of acidity (CL(A)) estimated using alkalinity range from 0.0827 to 9.48 keq ha?1 yr?1. Sulphur deposition estimates range from 0.0113 to 0.303 keq ha?1 yr?1 and do not exceed the estimated CL(A) at any of the study lakes. The spatial situation of both the lakes and the emission sources is responsible for the lack of exceedances, and expanded/continued monitoring is recommended to account for geological variability and source proliferation. Measurements of lake conductivity and alkalinity provide a means of community monitoring for freshwater acidification sensitivity as part of cumulative effects management strategies.  相似文献   

15.

Many planning agencies and stakeholder groups experimented with innovative forms of public involvement in the 1990s. British Columbia is one such jurisdiction which embraced the concept of public involvement in a broad range of land and resource management planning scales - to the degree of collaborative planning with communities, using consensus. The purpose of this paper is to present lessons for planners, supported by literature and by research in British Columbia, Canada from 1995-97, on these public involvement processes. Building on earlier 'typologies' for public involvement in planning, it proposes a strategic approach for identifying and analysing stakeholders, for setting objectives and for subsequently choosing the most appropriate level of public involvement.  相似文献   

16.
ABSTRACT Significant parameters for predicting thunderstorm runoff from small semiarid watersheds are determined using data from the Walnut Gulch watershed in southern Arizona. Based on these data, thunderstorm rainfall is dominant over watershed parameters for predicting runoff from multiple linear regression equations. In some cases antecedent moisture added significantly to the models. A technique is developed for estimating precision of predicted values from multiple linear regression equations. The technique involves matrix methods in estimating the variance of mean predicted values from a regression equation. The estimated variance of the mean predicted value is then used to estimate the variance of an individual predicted value. A computer program is developed to implement these matrix methods and to form confidence limits on predicted values based on both a normality assumption and the Chebyshev inequality.  相似文献   

17.
We evaluated a simple bioassessment method based on a priori river typology to predict benthic macroinvertebrate fauna in riffle sites of rivers in the absence of human influence. Our approach predicted taxon lists specific to four river types differing in catchment area with a method analogous to the site-specific RIVPACS-type models. The reference sites grouped in accordance with their type in NMS ordination, indicating that the typology efficiently accounted for natural variation in macroinvertebrate assemblages. Compared with a null model, typology greatly increased the precision of prediction and sensitivity to detect human impairment and strengthened the correlation of the ratio of observed-to-expected number of predicted taxa (O/E) with the measured stressor variables. The performance of the typology-based approach was equal to that of a RIVPACS-type predictive model that we developed. Exclusion of rarest taxa with low occurrence probabilities improved the performance of both approaches by all criteria. With an increasing inclusion threshold of occurrence probability, especially the predictive model sensitivity first increased but then decreased. Many common taxa with intermediate type-specific occurrence probabilities were consistently missing from impacted sites, a result suggesting that these taxa may be especially important in detecting human disturbances. We conclude that if a typology-based approach such as that suggested by the European Union’s Water Framework Directive is required, the O/E ratio of type-specific taxa can be a useful metric for assessment of the status of riffle macroinvertebrate communities. Successful application of the approach, however, requires biologically meaningful river types with a sufficient pool of reference sites for each type.  相似文献   

18.
Adaptive management: Promises and pitfalls   总被引:3,自引:1,他引:3  
Proponents of the scientific adaptive management approach argue that it increases knowledge acquisition rates, enhances information flow among policy actors, and provides opportunities for creating shared understandings. However, evidence from efforts to implement the approach in New Brunswick, British Columbia, Canada, and the Columbia River Basin indicates that these promises have not been met. The data show that scientific adaptive management relies excessively on the use of linear systems models, discounts nonscientific forms of knowledge, and pays inadequate attention to policy processes that promote the development of shared understandings among diverse stakeholders. To be effective, new adaptive management efforts will need to incorporate knowledge from multiple sources, make use of multiple systems models, and support new forms of cooperation among stakeholders.  相似文献   

19.
One of the primary challenges in resource and environmental planning is successful implementation of plans. Plan implementation is a complex process influenced by many factors. This study identifies 19 criteria affecting implementation success and tests the impact of these criteria through a case study of collaborative plan implementation in British Columbia, Canada. The significance of criteria and degree to which they are met is assessed by a survey of senior officials responsible for plan implementation. An implementation evaluation index (IEI) is constructed to assess the quality of plan implementation systems and best practices for effective implementation are identified.  相似文献   

20.
Summary With the passage of the Land Commission Act in April 1974, the province of British Columbia emerged as one of the leading innovators in agricultural land protection in North America. The British Columbia programme is unique, in that it encompasses a variety of incentives and disincentives to restrict the development of agricultural resources. While evidence suggests that the program has been quite successful, administrative weaknesses could endanger long-term viability. Regardless of the potential problems, British Columbia's experiences provide valuable lessons for other North American governments.Owen J. Furuseth is an Assistant Professor of Geography & Earth Sciences at the University of North Carolina at Charlotte. He received his A.B. degree (1971) in geography and urban planning from East Carolina University and an MA (1973) from the same institution in geography. His Ph.D. (1978) was earned in geography at Oregon State University.Prior to his current academic appointment he was an Associate Planner with the Jacksonville Area Planning Board in Jacksonville, Florida. His responsibilities with the agency included land use and environmental planning.His primary research interests are in the areas of agricultural land alienation, and policies to reduce these losses. During 1980–1981, Furuseth was a NATO Postdoctoral Fellow affiliated with the graduate program in Natural Resources Management at Simon Fraser University, British Columbia, Canada. The research reported in this paper was carried out and completed while he was in Canada.  相似文献   

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