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1.
A water quality assessment was conducted on three Appalachian streams polluted by coal mining at the Big South Fork National River and Recreation Area, Tennessee and Kentucky. Results showed that sulfate was an excellent parameter for detecting the effects of coal mining and that sulfate analyses used in conjunction with conductivity readings provided the best detection index. Acidity and pH readings were relatively insensitive indicators, reflecting the mining pollution only after sulfate concentrations already indicated severe pollution levels.Hydrologist, Big South Fork NRRA, during the study; presently at Cape Lookout National SeashoreHydrologist, NPS, during the study; presently with USDA-Forest Service, Washington, DC. 相似文献
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Grant R. Sutherland Elizabeth Baker Stuart Purvis-Smith Athel Hockey Ed Krumins Sam Z. Eichenbaum 《黑龙江环境通报》1987,7(3):197-202
Eleven pregnancies in ten patients at risk for the fragile X were monitored by amniocentesis or chorion villus biopsy and induction of the fragile site using thymidine, methotrexate and FUdR. Three female fetuses and one male fetus were found to have the fragile X. The results obtained using thymidine induction were superior to those using methotrexate induction and probably better than those obtained using FUdR induction. 相似文献
4.
This paper examines the relationship between North American beef consumption and deforestation in South and Central America.
Some writers have argued that consumption of hamburgers in North America, particularly hamburgers consumed in fast food restaurants,
contributes to the depletion of the rainforest in South and Central America. We survey the published policy literature on
the causes of rainforest depletion in the region. We also review the published estimates of the rate and extent of clearing
of rainforest that has occurred in South and Central America since 1970. Finally, we review the data on beef imports and consumption
in Canada and the United States in a effort to assess the importance of South and Central America as suppliers of beef to
the North American market. We conclude that the relationship between beef consumption in North America should not be considered
an important cause of forest depletion in South and Central America. Domestic policies and market forces in the countries
where rainforests are located are the leading causes of rainforest depletion in this region. This lesson seems to have been
lost on some popular and even some textbook writers on this subject.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
5.
Sam S. Cruickshank Arpat Ozgul Silvia Zumbach Benedikt R. Schmidt 《Conservation biology》2016,30(5):1112-1121
Accurate trend estimates are necessary for understanding which species are declining and which are most in need of conservation action. Imperfect species detection may result in unreliable trend estimates because this may lead to the overestimation of declines. Because many management decisions are based on population trend estimates, such biases could have severe consequences for conservation policy. We used an occupancy‐modeling framework to estimate detectability and calculate nationwide population trends for 14 Swiss amphibian species both accounting for and ignoring imperfect detection. Through the application of International Union for Conservation of Nature Red List criteria to the different trend estimates, we assessed whether ignoring imperfect detection could affect conservation policy. Imperfect detection occurred for all species and detection varied substantially among species, which led to the overestimation of population declines when detectability was ignored. Consequently, accounting for imperfect detection lowered the red‐list risk category for 5 of the 14 species assessed. We demonstrate that failing to consider species detectability can have serious consequences for species management and that occupancy modeling provides a flexible framework to account for observation bias and improve assessments of conservation status. A problem inherent to most historical records is that they contain presence‐only data from which only relative declines can be estimated. A move toward the routine recording of nonobservation and absence data is essential if conservation practitioners are to move beyond this toward accurate population trend estimation. 相似文献
6.
The siting of facilities with undesirable environmental characteristics often leads to public conflict. Efforts to resolve the conflict and make siting decisions frequently exacerbate the problem. Environmental mediation, the process of negotiating an agreeable settlement, is an accepted approach to resolving conflict. This paper explores the use of incentive systems as a means of achieving equity in environmental mediation. Obnoxious and noxious characteristics of facilities are discussed as the basis of conflicts. Four types of incentives—mitigation, compensation, reward, and participation—are discussed. The paper concludes with a discussion of the utility and application of incentives for solving environmental conflicts. 相似文献
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CO2 storage capacity estimation: Methodology and gaps 总被引:3,自引:0,他引:3
Stefan Bachu Didier Bonijoly John Bradshaw Robert Burruss Sam Holloway Niels Peter Christensen Odd Magne Mathiassen 《International Journal of Greenhouse Gas Control》2007,1(4):430-443
Implementation of CO2 capture and geological storage (CCGS) technology at the scale needed to achieve a significant and meaningful reduction in CO2 emissions requires knowledge of the available CO2 storage capacity. CO2 storage capacity assessments may be conducted at various scales—in decreasing order of size and increasing order of resolution: country, basin, regional, local and site-specific. Estimation of the CO2 storage capacity in depleted oil and gas reservoirs is straightforward and is based on recoverable reserves, reservoir properties and in situ CO2 characteristics. In the case of CO2-EOR, the CO2 storage capacity can be roughly evaluated on the basis of worldwide field experience or more accurately through numerical simulations. Determination of the theoretical CO2 storage capacity in coal beds is based on coal thickness and CO2 adsorption isotherms, and recovery and completion factors. Evaluation of the CO2 storage capacity in deep saline aquifers is very complex because four trapping mechanisms that act at different rates are involved and, at times, all mechanisms may be operating simultaneously. The level of detail and resolution required in the data make reliable and accurate estimation of CO2 storage capacity in deep saline aquifers practical only at the local and site-specific scales. This paper follows a previous one on issues and development of standards for CO2 storage capacity estimation, and provides a clear set of definitions and methodologies for the assessment of CO2 storage capacity in geological media. Notwithstanding the defined methodologies suggested for estimating CO2 storage capacity, major challenges lie ahead because of lack of data, particularly for coal beds and deep saline aquifers, lack of knowledge about the coefficients that reduce storage capacity from theoretical to effective and to practical, and lack of knowledge about the interplay between various trapping mechanisms at work in deep saline aquifers. 相似文献
9.
Tae Won Lee Michael J. Miller Hak Bin Hwang Sam Wouthuyzen Katsumi Tsukamoto 《Marine Biology》2008,153(3):285-295
Leptocephali of the widely distributed tropical marine eels of the genus Kaupichthys (family Chlopsidae) were collected around Sulawesi Island during a sampling survey in the Indonesian Seas in late September
and early October 2002, and the otolith microstructure of 24 of the 59 specimens captured was examined to learn about the
larval growth rates and spawning times of these small sized eels. Leptocephali ranging in size from 25 to 60 mm were collected
in Makassar Strait and the Celebes Sea, but they were most abundant in the semi-enclosed Tomini Bay of northeast Sulawesi
Island. The Kaupichthys leptocephali examined had 39–161 otolith growth increments. Their back-calculated hatching dates indicated that five age
groups were present and each group appeared to have been spawned around the full moon of previous months. Average growth rate
estimates of the first two age groups were 0.65 and 0.54 mm/day for the 27.4–30.4 and 37.6–45.6 mm age classes. The growth
rates of the oldest three age groups (52.0–60.8 mm) appeared to have slowed down after they reached their approximate maximum
size. An increase in increment widths at the outer margin of the otoliths of those larger than 53 mm suggested that the process
of metamorphosis had begun even though there were few external morphological changes indicating metamorphosis. It is hypothesized
that chlopsid leptocephali have an unusually short gut that may not need to move forward during early metamorphosis. The presence
of four age classes in Tomini Bay suggests that the Togian Islands region may be productive habitats for Kaupichthys juveniles and adults. 相似文献
10.
Yin Fun Yik Chye Peng Ong Soo Beng Khoo Hian Kee Lee Sam Fong Yau Li 《Environmental monitoring and assessment》1991,19(1-3):73-81
The effect of varying SDS concentration in a micellar electrokinetic capillary chromatographic system (MECC) is investigated. In addition, the introduction of -cyclodextrin as modifier to the electrophoretic medium, containing SDS and a phosphate-borate buffer, is shown to give satisfactory separation of the seven selected PAHs. The separation efficiency is increased with the addition of -cyclodextrin. 相似文献