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111.
Ulrich Lüttge 《Die Naturwissenschaften》1985,72(11):557-566
112.
Using the reproductive capacity of fish appears to be a suitable approach for risk assessment in the aquatic environment since fish are a typical representative thereof and in addition they are of considerable societal value. Generally the early embryonic stages are considered to be one of the most sensitive parts of a fish's life cycle. A method has been developed to use the state of health of live, naturally spawned fish embryos from plankton samples for biological effects monitoring. During the years 1985–1987 in the southern North Sea and in 1991–1992 in the whole of the North Sea fish eggs were sampled from surface waters and examined for developmental abnormalities. Elevated embryo malformation rates were detected in the plume of the major rivers Elbe and Rhine as well as along the eastern coast of England. Occurring malformations are thought to be pollution-related and may be used to define areas of environmental deterioration. The method is discussed in view of its suitability for biological effects monitoring using malformations in fish embryos as biomarkers. 相似文献
113.
Thomas Knoke Michael Weber 《Mitigation and Adaptation Strategies for Global Change》2006,11(3):579-605
The study presents a comprehensive methodology for the appraisal of C-stock expansion in existing forests as a forest management
activity according to Art. 3.4 of the Kyoto Protocol. It allows for producer costs of carbon sequestration in forest enterprises
to be derived. The methodology is based on a non-linear programming approach considering economic optimisation as well as
ecological, social and sustainability needs through constraints and risk integration. While introducing further constraints
on carbon stocks, the carbon stored in forest biomass was increased in periodic increments. However, while extending the carbon
stocks, the ecological and social constraints as well as sustainability requirements are not to be violated. Costs were derived
for every additional Mg (Megagrams) of C per ha sequestered in comparison to a baseline management.
Two basic cases were considered: First, a permanent carbon sequestration was assumed. Secondly, a temporary storage of additional
carbon over 10 years was supposed. The potential willingness of buyers of carbon certificates to pay for temporary carbon
sequestration was derived by a financial consideration. We assumed that, for a buyer, the value of a temporary carbon sequestration
certificate would be equivalent to the return on the savings because an investment in technical measures on reduction of carbon
emissions can be postponed. 相似文献
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Trisomy 7 mosaicism was detected prenatally in cultured amniocytes but not in fetal lymphocytes. The child that was born had pigmentary changes of the skin and facial asymmetry suggestive of a chromosomal mosaicism. Skin fibroblasts were studied and trisomy 7 mosaicism was confirmed. At 3 years of age the boy had developed mentally within normal limits. However, dysmorphic findings include sparse hair, short leftpalpebral fissure, ptosis of the left eyelid, strabismus, enamel dysplasia, low-set and posteriorly rotated ears and undescended testes. These findings share some common features with previously reported cases of trisomy 7 mosaicism. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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The problems of reproduction of Octopus vulgaris and the seasonal distribution in the sea of planktonic larvae, benthonic juveniles and adults are discussed. The influence of environmental factors on growth is shown by experimental studies in the laboratory, and the difficulties of interpreting field data are emphazised.Dedicated to Professor Dr. Adolf Portmann on his 75th birthday, 27 May, 1972Laboratoire associé au C.N.R.S. 相似文献
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