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61.
Cost estimates are frequently developed to evaluate hazardous‐waste‐site cleanup options in support of a site investigation, remedy selection decision, or assessment of environmental liabilities. The accuracy of the cost estimate depends largely on the quality of the information available at the time it is prepared. This article presents a practical guide to developing a cleanup cost estimate. It includes information on how to document assumptions, use the latest technical resources, and perform basic adjustments to account for uncertainty and the time value of money. The content is based upon a recent guidance document issued by the U.S. Environmental Protection Agency and U.S. Army Corps of Engineers entitled A Guide to Developing and Documenting Cost Estimates during the Feasibility Study (USEPA, 2000). © 2001 John Wiley & Sons, Inc. 相似文献
62.
ABSTRACT: Longitudinal succession indicates that diversity and species richiess of fish communities increases with increasing river size (increasing habitat complexity and environmental stability). Cultural impacts tend to decrease diversity, species richness, and evenness. To assess the impacts of cultural events on the fish community of a river system, the bias caused by longitudinal succession was removed by normalizing diversity indices and species richness values for river size. The relationships between an impact index and the community parameters of evenness, normalized diversity, and normalized species richness were determined by regression analysis. Similar relationships were determined using nonnormalized data, and the results compared. The two sets of regressions were similar in terms of variance explained. Evenness, which is unaffected by longitudinal sucession, appears to be the most impact sensitive parameter. A major source of error and confusion rsults from introduced species which are simultaneously sources of biological impact and a component of the community. Numbers of introduced species tend to increase with both impact and river size. 相似文献
63.
Third World countries are not pursuing scientific and technological policies leading to the development of strong biotechnological industries. Their leaders have been misled into believing that modern biotechnological industries can be built in the absence of strong, intellectually aggressive, and original scientific schools. Hence, they do not strive to reform their universities, which have weak commitments to research, and do not see the importance of having research hospitals able to generate excellent and relevant clinical investigation. These strategic gaps in scientific capability, the lack of governmental and corporate research funding, and the dependent nature of the chemical and pharmaceutical industries of the Third World make the development of competitive biotechnology a highly improbable event. If the present trend continues, underdeveloped countries will continue to be testing grounds for biological materials and agents, sources of valuable germplasm, and markets for high-value-added products and processes invented and manufactured in the First World. This article recommends that the international organizations collaborate in the urgent task of educating the Third World political leaders and administrators in the real problems connected with the generation of high technology. 相似文献
64.
Jennifer Goldstein Scott Heppell Andrew Cooper Solange Brault Molly Lutcavage 《Marine Biology》2007,151(6):2063-2075
The reproductive status and body condition of 195 (≥185 cm curved fork length, CFL; assigned age 7 and above) Atlantic bluefin
tuna were assessed in the Gulf of Maine during the commercial fishing season of June–October, 2000–2002. Given the distance
between known spawning and feeding grounds, the prevailing paradigm for Atlantic bluefin tuna (Thunnus thynnus thynnus, L.) suggests that the most likely histological state for females arriving in the Gulf of Maine after spawning would be a
resting or quiescent state with little or no perigonadal fat. Alternatively, the presence of mature or mature-inactive histological
states in some females supports a more varied or individualistic model for bluefin reproduction. No relationship was found
between body condition and reproductive status. Males were found in all reproductive stages, but were more likely to be in
spawning condition (stages 4 and 5) or a mature-inactive state (stage 6) in June and July. Female bluefin tuna were found
in stage 1 (immature or non-spawning) and stage 6 (mature-inactive). Stage 6 females were only present in June and July and
smaller females (<235 cm CFL) were more likely to be in stage 6 than large females (>235 cm CFL) sampled during those same
months. The presence of smaller females in stage 6 arriving at the same time as larger females in stage 1 indicates that Western
Atlantic bluefin tuna may have an asynchronous reproductive schedule and may mature at a smaller size than the currently accepted
paradigm suggests. 相似文献
65.
The purpose of this study was to measure anxiety in pregnant women who had low maternal serum alpha-fetoprotein (MSAFP) screening test levels, received genetic counselling and chose to undergo amniocentesis for fetal chromosome analysis. Their anxiety levels were compared with the levels in women undergoing amniocentesis because of advanced maternal age. The results indicate a higher level of anxiety in women with low alpha-fetoprotein (AFP) levels. 相似文献
66.
COMPARISON OF TRACE ELEMENT CONCENTRATIONS IN TISSUE OF COMMON CARP AND IMPLICATIONS FOR MONITORING1
Robert M. Goldstein L. Rod DeWeese 《Journal of the American Water Resources Association》1999,35(5):1133-1140
Common carp (Cyprinus carpio) collected from four sites in the Red River of the North in 1994 were analyzed for arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), nickel (Ni), selenium (So), and zinc (Zn). Concentrations differed among liver, muscle, and whole body. Generally, trace element concentrations were the greatest in livers while concentrations in whole bodies were greater than those in muscle for Cd, Cu, Ni, Pb, and Zn, and concentrations in muscle were similar to whole body for As and Se. Concentrations of Cr were lower in liver than either muscle or whole body. Correlations between liver and whole body concentrations were stronger than those between liver and muscle concentrations, but the strongest correlations were between muscle and whole body concentrations. Examination of tissue concentrations by collection sites suggested that, for a general survey, the whole body may be the most effective matrix to analyze. 相似文献
67.
Kathy E. Lee Robert M. Goldstein Paul E. Hanson 《Journal of the American Water Resources Association》2001,37(6):1465-1473
ABSTRACT: The relation offish community composition to riparian cover at two spatial scales was compared at 18 streams in the agricultural Minnesota River Basin. The two spatial scales were: (1) local riparian zone (a 200 meter wide buffer extending 2 to 3 kilometers upstream of the sampling reach); and (2) the upstream riparian zone (a 200 m wide buffer on the mainstem and all perennial tributaries upstream of the sampling reach). Analysis of variance indicated that streams with wooded‐local riparian zones had greater fish species richness (means = 20 and 15, respectively) and Index of Biotic Integrity (IBI) scores (means = 40 and 26, respectively) than streams with open‐local riparian zones. Streams with wooded‐upstream riparian zones tended (were not statistically significant) to have greater numbers of species (means = 19 and 15, respectively) and IBI scores (means = 33 and 28, respectively) than streams with open‐upstream riparian zones. There was no significant interaction between the riparian zone conditions at the two scales. This study suggests that maintenance of wooded riparian cover along streams could be effective in maintaining or improving fish community composition in streams draining heavily agricultural areas. 相似文献
68.
Marlo K. Sellin Daniel D. Snow Debbie L. Akerly Alan S. Kolok 《Journal of the American Water Resources Association》2009,45(1):14-21
Abstract: Recent studies have detected estrogenic compounds in surface waters in North America and Europe. Furthermore, the presence of estrogenic compounds in surface waters has been attributed, in some cases, to the discharge of wastewater treatment plant (WWTP) effluent. The primary objective of the current study was to determine if WWTP effluent contributes estrogens to the surface waters of Nebraska. A second objective of this study was to determine if estrogens were found in concentrations sufficient enough to manifest feminizing effects on fish. These objectives were satisfied by deploying polar organic chemical integrative samplers (POCIS) and caged fathead minnows at eight field sites. Deployment sites included: three reference sites (Pawnee Creek, the Little Blue River, and the Middle Loup River), two sites upstream of the WWTPs at Grand Island and Columbus, and three sites downstream of the WWTPs at Grand Island, Columbus, and Hastings. Following the seven day deployments, POCIS extracts were analyzed for estrone, 17β‐estradiol, estriol and 17α‐ethinylestradiol using liquid chromatography tandem mass spectrometry (LC/MS/MS). 17β‐estradiol was detected in POCIS from six of the eight field sites with the greatest quantities recovered in POCIS deployed downstream from the Grand Island and Hastings WWTPs. Estrone was detected only in the POCIS deployed downstream from the Grand Island and Hastings WWTPs. Estrogenic effects were detected in caged minnows analyzed for the hepatic mRNA expression of two estrogen‐responsive genes, vitellogenin (vg1) and estrogen receptor α (ERα). Fish deployed at the site where the greatest quantities of estrogens were recovered (Hastings) had significantly higher expression of both vg1 and ERα than fish deployed at any of the other sites. These results confirm that WWTP effluent contributes biologically significant levels of estrogens to Nebraska surface waters. 相似文献
69.
Carl W. Chen Joel W. Herr Robert A. Goldstein 《Journal of the American Water Resources Association》2008,44(5):1295-1307
Abstract: The Watershed Analysis Risk Management Framework watershed model was enhanced to simulate the transport and fate of mercury and to calculate the fish mercury concentrations (FMC) attained by fish through the food web. The model was applied to Western Lake Superior Basin of Minnesota, which has many peat lands and lakes. Topographic, land use, and soil data were used to set up the model. Meteorology and precipitation chemistry data from nearby monitoring stations were compiled to drive the model. Simulated flow and mercury concentrations for several stream stations were comparable to available data. The model was used to perform mercury total maximum daily load calculations for two contrasting drainage lakes (Wild Rice Lake and Whiteface Reservoir). The model results for wet deposition, dry deposition, evasion, watershed yield, and soil sequestration of mercury were comparable with available actual data. The model predicted lake ice cover from November to April and weak stratification in summer, typical of shallow lakes in cold regions. The simulated sulfate decrease and methylmercury increase near the lake bottom in late summer are caused by sulfate reduction and mercury methylation that occur in the surficial sediment. Simulated FMC were within the range of observed values and the R2 of correlation between the simulated and observed FMC was 0.77. Under the 1989‐2004 base condition, the average simulated FMC of four‐year‐old walleye was 0.31 μg/g for Whiteface Reservoir and 0.15 μg/g for Wild Rice Lake. The FMC criterion in Minnesota is 0.2 μg/g. Wild Rice Lake already meets this criterion without any load reduction. The model showed that a 65% reduction in atmospheric mercury deposition will not, by itself, allow Whiteface Reservoir to meet the criterion in 15 years. Additional best management practices will be needed to reduce 50% of the watershed input. 相似文献
70.
Michael P. Labare J. Timothy Bays Michael A. Butkus Teresa Snyder-Leiby Alicia Smith Amanda Goldstein Jenna D. Schwartz Kristopher C. Wilson Melody R. Ginter Elizabeth A. Bare Robert E. Watts Elizabeth Michealson Nicole Miller Rachel LaBranche 《Environmental science and pollution research international》2010,17(4):1009-1015