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951.
Determination of the distribution coefficient (log Kd) of oxytetracycline,tylosin A,olaquindox and metronidazole in manure 总被引:2,自引:0,他引:2
Olaquindox (log Kow = -2.3) and metronidazole (log Kow = -0.1) both have low tendencies to sorp to particles in manure. This corresponds with the negative log Kow values of these antibiotics. Tylosin (log Kow = 1.63) and oxytetracycline (log Kow = -1.12) sorp relatively strongly to the manure particles and have log Kd values between 1.5 and 2.0. The tendency to bind to manure was ranked after increasing binding as follows: metronidazole < olaquindox < tylosin A and oxytetracycline. This order of ranking is consistent with results of sorption in soil. Our experiments illustrate that for some antibacterial agents estimation of the partitioning coefficients, Kd, cannot be made from Kow and f(oc) alone. Sorption of oxytetracycline to manure is much higher than expected from the negative log Kow value of the compound. It is believed that sorption of oxytetracycline to manure is influenced by ionic binding to divalent metal ions as such Mg2+ and Ca2+ as well as other charged compounds in the matrix. Binding of oxytetracycline to soil is stronger than the binding to manure. This is most likely due to the strong mineral related metal complexes formed between soil, metal ion and oxytetracycline. These complexes are not known to exist in manure. The relatively strong sorption of tylosin A to manure corresponds with data found for soil sorption of tylosin. Tylosin has a log Kow value of 2.5, thus it is not surprising that this drug binds strongly to manure. 相似文献
952.
The Swedish coastal zone is a scene of conflicting interests about various goods and services provided by nature. Open-access conditions and the public nature of many services increase the difficulty in resolving these conflicts. "Sustainability" is a vague but widely accepted guideline for finding reasonable trade-offs between different interests. The UN view of sustainable development suggests that coastal zone management should aim at a sustainable ecological, economic, and social-cultural development. Looking closer at economic sustainability, it is observed that economic analyses about whether changes in society imply a gain or a loss should take into account the economic value of the environment. Methods used for making such economic valuation in the context of the Swedish coastal zone are briefly reviewed. It is noted that the property rights context matters for the results of a valuation study. This general background is followed by a concise presentation of the design and results of four valuation studies on Swedish coastal zone issues. One study is on the economic value of an improved bathing water quality in the Stockholm archipelago. The other studies are a travel cost study about the economic value of improved recreational fisheries in the Stockholm archipelago, a replacement cost study on the value of restoring habitats for sea trout, and a choice experiment study on the economic value of improved water quality along the Swedish westcoast. 相似文献
953.
Lene Hansen Egon Noe Katrine Højring 《Journal of Agricultural and Environmental Ethics》2006,19(2):147-168
The relationship between agriculture and nature is a central issue in the current agricultural debate. Organic Farming has
ambitions and a special potential in relation to nature. Consideration for nature is part of the guiding principals of organic
farming and many organic farmers are committed to protecting natural qualities. However, the issue of nature, landscape, and
land use is not straightforward. Nature is an ambiguous concept that involves multiple interests and actors reaching far beyond
farmers. The Danish research project Nature Quality in Organic Farming has investigated the relationship between nature and organic farming. This article will focus on an expert workshop held
in connection with the project that investigates the way different actors conceptualize nature. Farmers, scientists, and non-governmental
organizations came together to discuss their experiences of nature and expectations of organic agriculture. From this interaction,
it was clear that nature is a contested notion. Different understandings of nature exist within the three groups and there
is disagreement as to whether emphasis should be given to biological qualities, production values, or experiential and aesthetic
perspectives. This complexity provides a challenge to organic farming as well as to the implementation of nature considerations
in general. It illustrates an underlying battle for the right to define nature and nature quality and essentially decide what
organic farmers should work towards. We argue that successful implementation requires organic farmers to carefully consider
what expectations they wish to meet. Optimally it is dependent on a dialog between stakeholder interest groups that allows
for multivocality and pluralism. 相似文献
954.
Karsten Klint Jensen Jan Tind Sørensen 《Journal of Agricultural and Environmental Ethics》1998,11(2):85-100
This paper presents the idea of a decision-support system for a livestock farm, called “ethical accounting”, to be used as
an extension of traditional cost accounting. “Ethical accounting” seeks to make available to the farmer information about
how his decisions affect the interests of farm animals, consumers and future generations. Furthermore, “ethical accounting”
involves value-based planning. Thus, the farmer should base his choice of production plan on reflections as to his fundamental
objectives, and he should make his final decision only after having seriously considered the various consequences for the
affected parties.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
955.
956.
Sygna Linda Fuglestvedt Jan S. Aaheim H. Asbjørn 《Mitigation and Adaptation Strategies for Global Change》2002,7(1):45-62
This article looks at the ability of Global Warming Potentials (GWPs) towork as indicators of equivalence for temperature development and damagecosts. We look at two abatement scenarios that are equivalent when using100-year GWPs: one scenario reduces short-lived gases, mainly methane(CH4); the other scenario reduces carbon dioxide (CO2).Despite their equivalence in terms of CO2 equivalents, the scenariosdo not result in equal rates or levels of temperature change. The disparitiescontinue as we move further down the chain of causality toward damagecosts, measured either in terms of rate of climate change or level of climatechange. Compared to the CH4 mitigation scenario, the CO2mitigation scenario gives present value costs 1.3 and 1.5 times higher forlevel- and rate-dependent damage costs, respectively, assuming a discountrate of 3%. We also test the GWPs for other time horizons and theconclusions remain the same; using GWP as an index to reflect equivalentclimate effects and damage costs from emissions is questionable. 相似文献
957.
E. Schnepi L. Jaenicke K. Krickeberg G. Schumann G. Höhler W. Bruch D. Jung K. J. Euler C. K. Jørgensen P. Zuman J. Goubeau H. Schmidbaur L. Horner W. P. Neumann W. A. Bingel T. Reichstein W. Sandritter C. H. Eugster R. Dietz G. Ohloff H. Markl M. Lindauer 《Die Naturwissenschaften》1970,57(4):200-204
958.
Chromosome analysis in a boy aged 10 months, with psychomotor retardation, revealed the fragile X-chromosome in lymphocytes and skin fibroblasts cultured in low folate medium (TC 199). Amniocentesis and chromosomal analysis had been carried out during pregnancy because of advanced maternal age. Review of the slides from amniotic fluid cells grown routinely in low folate medium showed the marker X in 10.6 per cent of the metaphases. Possible explanations for the appearance of the marker X in amniotic cell culture are discussed. 相似文献
959.
Finn Stener Jørgensen MD Jens Bang Lisbeth Tranebjærg Lillian N. Berge Sturla H. Eik-Nes Marianne Schwartz 《黑龙江环境通报》1994,14(2):149-152
We present a case of prenatal diagnosis of cystic fibrosis (CF) in one twin at 11–12 weeks of gestation. The parents had previously had two children, one of whom is alive and healthy and one who died of CF at the age of 2½ months. The parents were both known to be carriers of the ΔF508 mutation. Chorionic villus sampling (CVS) was performed and direct gene analysis showed that one fetus was homozygous for the ΔF508 mutation, while the other fetus did not have the mutation at all. Both fetuses had normal karyotypes. Selective termination was subsequently performed. The pregnancy continued without complications except for mild pre-eclampsia at term. The woman had a Caesarean section. The genetic diagnosis was confirmed after birth. 相似文献
960.