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871.
Five species of Sepiola and Sepictta were reared in the laboratory from egg to adult size. Spawning was achieved in 3 species of Sepiola after 5 to 7 months. The growth rate of the species reared did not depend upon temperature, which ranged from 12.5° to 20°C. A fairly constant size increase (2.5 mm mantle length/month) was observed in Sepiola during the 5 months after hatching. In Sepietta, the same growth rate was observed until the fourth month after hatching, when it increased to the rate of 5 mm mantle length/month.Laboratoire associé au C.N.R.S. 相似文献
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874.
Green liquor dregs is the biggest waste fraction at sulphate pulp mills. It is commonly landfilled. Here we demonstrate that
the utilization of green liquor dregs as a neutralizing agent for acidic wastewaters is a potential alternative and an environmentally
friendly method in contrast to its landfill disposal. The liming effect value of 39.6% for green liquor dregs, expressed as
Ca equivalent, is similar to the liming effect value of 38% of a commercial limestone product. In addition, the pH value of
10.7 indicates a strong liming effect. 相似文献
875.
Marco Tasin Anna-Carin Bäckman Marie Bengtsson Nélia Varela Claudio Ioriatti Peter Witzgall 《Chemoecology》2006,16(2):87-92
Summary. Host plant volatiles which attract insect herbivores for egg-laying are of principal interest with respect to insect ecology
and evolution. Direct applications concern population monitoring and control through behavioural manipulation. Identification
of behaviourally active plant secondary metabolites is essential also for plant breeding for insect resistance. Grapevine
moth females Lobesia botrana are attracted by upwind flight to green grape berries Vitis vinifera. The headspace of grape berries was collected on air filters. A solvent extract of these filters, released from a sprayer,
attracted females in the wind tunnel. The results demonstrate that volatile cues mediate attraction of grapevine moth females
to grape berries, and that headspace collections capture the essence of this odour signal. The air filter extracts were examined
by gas chromatography coupled with electroantennographic detection, and the compounds eliciting a consistent antennal response
in L. botrana females were identified by mass spectrometry. The headspace collection apparatus was calibrated for collection efficiency
of the active compounds. Their recovery rate ranged from 35 % for methyl salicylate to 83 % for (E,E)-α-farnesene. A synthetic ten-component blend was then formulated. The blend consisted of compounds eliciting an antennal
response, formulated in a blend ratio corrected for differences in collection efficiency. Subsequent wind tunnel tests showed
that female attraction to this synthetic ten-component blend was not significantly different from attraction to grape berries,
or to headspace collections of the same berries. At a release rate of 35 ng/h of the most abundant compound (E)-β-caryophyllene,
20 % of the test females approached the source of sprayed headspace collections and the ten-component synthetic blend, respectively.
In comparison, 100 g of green berries, releasing the main compound (E)-β-caryophyllene at a rate of ca. 4.7 ng/h, attracted
10 % of the females by upwind flight followed by source contact. 相似文献
876.
Barbara Raffaelli Eija Leppälä Clément Chappuis Kristiina Wähälä 《Environmental Chemistry Letters》2006,4(1):1-9
Seven new dibenzylbutyrolactone and six new dibenzylbutanediol lignans were prepared to assist in the identification of a
number of potential mammalian metabolites of the endocrine disrupting plant lignans syringaresinol and medioresinol, present
in food. 相似文献
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879.
Christian Werner Friedrich Köpp Michael Klier Rainer Haus Wilfried Bautzer Klaus Schäfer 《Environmental Sciences Europe》1996,8(3):143-149
The combination of remote sensing methods like Doppler lidar and FTIR allows remote determination of mass fluxes of gases. Doppler lidar measures the three-dimensional wind vector in the vicinity of diffuse sources, or the velocity of air in a chimney plume if an industrial complex is monitored. FTIR is a multicomponent remote sensing method for gas concentrations. The Fourier transformation of an interferogram of a Michelson interferometer within a FTIR system converts the recorded intensity (function of optical path length) to a spectral signal (function of wavenumber). Both information, velocity and concentration, give the mass fluxes of the tracer (gas). A first test was performed at Munich-Nord power station with FTIR and cw-Doppler lidar. Fluxes of CO2, CO, NO, and HCl were determined. The results are in good agreement with the fluxes measured byin situ instruments of the power station. The method can be used to control industrial complexes from an outside observation site. 相似文献
880.
Jens Newig Nicolas W. Jager Elisa Kochskämper Edward Challies 《Journal of Environmental Policy & Planning》2019,21(3):213-227
ABSTRACTTheory on participatory and collaborative governance maintains that learning is essential to achieve good environmental outcomes. Empirical research has mostly produced individual case studies, and reliable evidence on both antecedents and environmental outcomes of learning remains sparse. Given conceptual ambiguities in the literature, we define governance-related learning in a threefold way: learning as deliberation; as knowledge- and capacity-building; and as informing environmental outputs. We develop nine propositions that explain learning through factors characterizing governance process and context, and three propositions explaining environmental outcomes of learning. We test these propositions drawing on the ‘SCAPE’ database of 307 published case studies of environmental decision-making, using multiple regression models. Results show that learning in all three modes is explained to some extent by a combination of process- and context-related factors. Most factors matter for learning, but with stark differences across the three modes of learning, thus demonstrating the relevance of this differentiated approach. Learning modes build on one another: Deliberation is seen to explain both capacity building and informed outputs, while informed outputs are also explained by capacity building. Contrary to our expectations, none of the learning variables was found to significantly affect environmental outcomes when considered alongside the process- and context-related variables. 相似文献