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231.
Osowski SL Swick JD Carney GR Pena HB Danielson JE Parrish DA 《Environmental monitoring and assessment》2001,66(2):159-185
Swine Concentrated Animal Feeding Operations (CAFOs) have received much attention in recent years. As a result, a watershed-based screening tool, the Cumulative Risk Index Analysis (CRIA), was developed to assess the cumulative impacts of multiple CAFO facilities in a watershedsubunit. The CRIA formula calculates an index number based on: 1) the area of one or more facilities compared to the area of the watershed subunit, 2) the average of the environmental vulnerability criteria, and 3) the average of the industry-specific impact criteria. Each vulnerability or impact criterion is ranked on a 1 to 5 scale, with a low rank indicating low environmental vulnerability or impact and a high rank indicating high environmental vulnerability or impact. The individual criterion ranks, as well as the total CRIA score, can be used to focus the environmental analysis and facilitate discussions with industry, public, and other stakeholders in the Agency decision-making process. 相似文献
232.
Clench-Aas J Bartonova A Grønskei KE Hagen LO Braathen OA Walker SE 《Journal of environmental monitoring : JEM》1999,1(4):341-347
This paper presents methodology and results of a dynamic individual air pollution exposure model (DINEX) that calculates the hourly exposure for each adult in a panel study. Each of over 260 participants, through the use of a diary, provided information used in the model to calculate his/her personal, individualised exposure. The participants filled out the diary daily, hour by hour, over two, two month periods. The exposure assessment model coupled the diary information and results of an indoor/outdoor measurement program, with the results of dispersion modelling on an hourly basis for an industrial area in Norway. The estimated air pollution concentrations from the dispersion model, based on continuous meteorological measurements, were calibrated with air pollutant concentrations measured continuously. 相似文献
233.
234.
Sunesson AL Sundgren M Levin JO Eriksson K Carlson R 《Journal of environmental monitoring : JEM》1999,1(1):45-50
Tube type samplers with two different adsorbents, Chromosorb 106 and Tenax TA, were evaluated by laboratory experiments and field tests for simultaneous diffusive sampling of alpha-pinene, beta-pinene and delta 3-carene and subsequent thermal desorption-gas chromatographic analysis. No statistically significant effects of exposure time, concentrations of monoterpenes or relative humidity were found for samplers with Chromosorb 106 when running a factorial design, with the exception of the adsorption of delta 3-carene, for which some weak effects were noted. Samplers with Tenax TA were affected by the sampling time as well as the concentration for all terpenes, with a strong interaction effect between these two factors. The terpenes showed good storage stability on both adsorbents. No effect of back-diffusion was noted when using Chromosorb 106, while Tenax TA showed some back-diffusion effects. The uptake rates, in ml min-1, for the terpenes on Chromosorb 106 were 0.36 for alpha-pinene, 0.36 for beta-pinene and 0.40 for delta 3-carene. The corresponding average values on Tenax TA were 0.30 for alpha-pinene, 0.32 for beta-pinene and 0.38 for delta 3-carene. The field validation proved that diffusive sampling on Chromosorb 106 agreed well with pumped sampling on charcoal for stationary samples, while the personal samples indicated a discrepancy of 25% between Chromosorb 106 and charcoal samples. Tenax TA generally gave lower results than Chromosorb 106 in all field samples. Samplers packed with Chromosorb 106 could be used to monitor terpene levels in workplaces such as sawmills. The major advantages with this method are the sampling procedure, which is simple to perform compared to other techniques, the easily automated analysis procedure and the possibility to reuse the samplers. 相似文献
235.
MARTIN A. STAPANIAN STEVEN P. CLINE DAVID L. CASSELL 《Environmental monitoring and assessment》1997,45(3):237-257
We evaluate a field method for determining species richness andcanopy cover of vascular plants for the Forest Health MonitoringProgram (FHM), an ecological survey of U.S. forests. Measurementsare taken within 12 1-m2 quadrats on 1/15 ha plots in FHM.Species richness and cover are determined for four height classes(strata) within each quadrat and aggregated by stratum over the entireplot. We estimated (1) the agreement between experienced trainers andinexperienced technicians who collected the data on this survey(accuracy) and (2) the agreement among the technicians (precision) forresults on species richness and cover from 3 test plots at 3 timeintervals. The methods appear to be highly precise, although somediscrepancies with the values obtained by the trainers were found.Trainers found significantly more species in the ground stratum (0–0.6 m) and measured significantly more cover in the uppermost stratum(>4.9 m). The proportion of variation due to measurement error andtemporal variability was less than 13% for species richness (all strata)and cover (all but one stratum). This indicates that the method issuitable for monitoring changes in species richness and canopy coverfor a large-scale synoptic monitoring project such as FHM. 相似文献
236.
Modeling rhizofiltration: heavy-metal uptake by plant roots 总被引:1,自引:0,他引:1
P. Verma K. V. George H. V. Singh S. K. Singh A. Juwarkar R. N. Singh 《Environmental Modeling and Assessment》2006,11(4):387-394
The discovery of phytoaccumulation potential of plant species has led to its application for remediation of heavy-metal-contaminated soil and wastewater, which is termed as phytoextraction/rhizofiltration. For prediction, analysis, planning and cost-effective design of such systems, mathematical models not only are used as a screening tool but also provide optimal parameters like harvesting time, irrigation schedule, etc. Several laboratory and field scale studies have been carried out in the past, and mathematical expressions have been developed by various researchers for different phenomena like metal adsorption in soil, plant root growth with time, moisture and metal uptake by plant root, moisture movement in unsaturated zone, soil moisture relationship, etc. The complete design of any such phytoremediation program would require the knowledge of behavior of heavy-metal movement in soil, water and plant root system. In this paper, a model for simulating heavy-metal dynamics in soil, water and plant root system is developed and discussed. The governing non-linear partial differential equation is solved numerically by implicit finite difference method using Picard's iterative technique, and the formulation has been illustrated using a characteristic example. The source code is written in MATLAB. 相似文献
237.
Georgios D. Gikas Trisevgeni Yiannakopoulou Vassilios A. Tsihrintzis 《Environmental Modeling and Assessment》2006,11(3):219-233
SWAT ver. 2000 was used to predict hydrographs, and sediment, nitrate and total phosphorus loadings from a 1349 km2 mountainous/agricultural watershed in Northern Greece. The model was calibrated and verified using continuous meteorological
data from eight stations within the drainage area, and runoff, sediment and nutrient concentrations measured at nine stations
located within the main tributaries of the watershed, for the time period from May 1st, 1998 to January 31st, 2000. Model
validation methodology and resulting input parameters appropriate for Mediterranean drainage basins are presented. Predicted
by the model hydrographs, sedimentographs and pollutographs are plotted against observed values and show good agreement. Model
performance is evaluated using the root mean square error computation and scattergrams of predicted versus observed data.
The validated model is also used to test the effectiveness of three alternative cropping scenarios in reducing nutrient loadings
from the agricultural part of the watershed. The study showed that this model, if properly validated, can be used effectively
in testing management scenarios in Mediterranean drainage basins. 相似文献
238.
Luis A. Gil-Alana 《Environmental Modeling and Assessment》2006,11(1):19-29
In this article we examine the stochastic behaviour of several daily datasets describing sun (total irradiance at the top
of the atmosphere and sunspot numbers) and various climatological anomaly series by looking at their orders of integration.
We use a testing procedure that permits us to consider fractional degrees of integration. The tests are valid under general
forms of serial correlation and deterministic trends and do not require estimation of the fractional differencing parameter.
Results show that the series are all nonstationary, with increments that might be stationary for those variables affecting
sun, and anti-persistent for those affecting air temperatures. 相似文献
239.
Gottfried Tappeiner Ulrike Tappeiner Janette Walde 《Environmental Modeling and Assessment》2007,12(4):253-256
The complexity of today’s research problems increasingly demands that scientists move beyond the confines of their own discipline.
In this special issue, the basics of a transdisciplinary framework are established and problems analyzed in a specific discipline
are successfully integrated in this transdisciplinary network. The intent has been to go beyond only statements about the
importance of enabling early stage researchers to work across disciplinary boundaries, and to show that important discoveries
are being made at the intersection of disciplines. Embedding various research projects in a more global framework can meet
the demands of an interdisciplinary or transdisciplinary approach (especially for early stage researchers) and contribute
significantly to sustainable research. 相似文献
240.
A study on the orbit of air temperature movement 总被引:1,自引:0,他引:1
Zong-Chang Yang 《Environmental Modeling and Assessment》2007,12(2):131-143
In this paper, we describe an air temperature movement by mapping its time series to the polar coordinates: the value of the
time series is plotted on the radial coordinate and the time on the angular coordinate. In this way, both the yearly and daily
air temperature movements from five different locations of China are used to demonstrate that, in an intuitionistic view,
air temperature movement is neither random nor chaotic, but has its own orbit. We then propose an elliptic orbit model for
the air temperature movement. Our proposed model provides quite good results when it is applied to the evaluation of yearly
air temperature movements in eight locations in various parts of the world, and the evaluation of daily air temperature movements
in five locations in Hunan Province of China on December 17, 2005. Results show that our approach provides a concise and helpful
model for air temperature analysis. 相似文献