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51.
Invasive plant suppresses charismatic seabird - the construction of attitudes towards biodiversity management options 总被引:1,自引:0,他引:1
Public attitudes towards biodiversity issues and the value judgments underlying biodiversity management and conservation are still poorly understood. This has raised serious concerns regarding the effective use of public participation in biodiversity policy making. We conducted quantitative face-to-face interviews with members of the general public in southeast Scotland to assess attitudes towards biodiversity management and examine attitude formation. For this, we applied social psychological attitude-behaviour theories to a case study investigating biodiversity management options for an island ecosystem in which the abundance of a charismatic seabird, the Atlantic puffin (Fratercula arctica) is compromised by the expansion of a tall invasive plant, tree mallow (Lavatera arborea). We found that attitudes as expressed by members of the public are informed by both value- and knowledge-based elements. Our research provides clear support for the notion that, in a conservation context, value-based principles matter to the public. Out of a set of seven conservation-related values, ‘balance’ and ‘naturalness’ were important factors that related strongly to the respondents’ attitudes. These relationships were even stronger for individuals emotionally involved with the topic. Other value-based principles such as uniqueness, autochthony and endangeredness of the species involved appeared to be of lesser relevance. The findings provide evidence that attitudes can be considered as distinct constructs that offer valuable and meaningful information to biodiversity policymakers and managers, and allow empirical insights into the way value judgments influence biodiversity management and conservation. 相似文献
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Yoon B Häkkinen H Landman U Wörz AS Antonietti JM Abbet S Judai K Heiz U 《Science (New York, N.Y.)》2005,307(5708):403-407
Gold octamers (Au8) bound to oxygen-vacancy F-center defects on Mg(001) are the smallest clusters to catalyze the low-temperature oxidation of CO to CO2, whereas clusters deposited on close-to-perfect magnesia surfaces remain chemically inert. Charging of the supported clusters plays a key role in promoting their chemical activity. Infrared measurements of the stretch vibration of CO adsorbed on mass-selected gold octamers soft-landed on MgO(001) with coadsorbed O2 show a red shift on an F-center-rich surface with respect to the perfect surface. The experiments agree with quantum ab initio calculations that predict that a red shift of the C-O vibration should arise via electron back-donation to the CO antibonding orbital. 相似文献
54.
M Grün M Anke A Hennig W Seffner M Partschefeld G Flachowsky B Groppel 《Archives of Animal Nutrition》1978,28(5):341-347
Lambs received 250, 1000 and 1750 mg Fe per kg concentrate dry matter. The Fe-supplementations caused the Fe-levels of spleen, liver, kidneys and ribs to rise significantly. Liver and spleen reflected most markedly the high Fe-supply. The Fe-supplementation reduced the Cu-content in the liver and the share of Zn in the kidneys. The Mn-content of all body parts analysed was not significantly influenced by Fe-supplementation. 相似文献
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Russell J. S. Orr Anke Stüken Shauna A. Murray Kjetill S. Jakobsen 《Marine drugs》2013,11(8):2814-2828
Numerous species of marine dinoflagellates synthesize the potent environmental neurotoxic alkaloid, saxitoxin, the agent of the human illness, paralytic shellfish poisoning. In addition, certain freshwater species of cyanobacteria also synthesize the same toxic compound, with the biosynthetic pathway and genes responsible being recently reported. Three theories have been postulated to explain the origin of saxitoxin in dinoflagellates: The production of saxitoxin by co-cultured bacteria rather than the dinoflagellates themselves, convergent evolution within both dinoflagellates and bacteria and horizontal gene transfer between dinoflagellates and bacteria. The discovery of cyanobacterial saxitoxin homologs in dinoflagellates has enabled us for the first time to evaluate these theories. Here, we review the distribution of saxitoxin within the dinoflagellates and our knowledge of its genetic basis to determine the likely evolutionary origins of this potent neurotoxin. 相似文献
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A laboratory study was undertaken to investigate the leaf systemic properties and the translaminar aphicidal activity of two commercialised neonicotinoid (chloronicotinyl) insecticides. For that purpose [14C]imidacloprid was subjected to uptake and translocation studies in cabbage and cotton after foliar application. Foliar penetration and short-term translocation patterns of imidacloprid were similar in both plant species. Nevertheless imidacloprid penetrated twice as much into cabbage leaves as it did into cotton leaves. It showed a comparable translaminar behaviour and was entirely translocated acropetally, indicating its well-known xylem mobility. The translaminar and acropetal movement of imidacloprid and acetamiprid were quantified by simple laboratory bioassays using the green peach aphid, Myzus persicae (Sulzer), and the cotton aphid, Aphis gossypii (Glover), as typical homopteran pests for cabbage and cotton, respectively. A single dose (7.5 micrograms AI per leaf) applied to the upper leaf surface of cabbage and cotton was tested against aphids feeding on the lower leaf surface both close to and distant from the site of application 1, 5 and 12 days after treatment. The translaminar residual activity of imidacloprid on cabbage leaves was superior to that of acetamiprid, whereas its translaminar efficacy against A gossypii on cotton was inferior to that of acetamiprid. However, oral ingestion bioassays using an artificial double membrane feeding system revealed no significant differences in intrinsic activity between the two neonicotinoids tested. 相似文献
60.
The ash content and the content of Ca, Mg, K, and Na in the bristles of pigs is influenced by the age of the animal and by the season of the year. The peak concentrations of ash, Ca and Mg in the bristles of eight boars (cut every month) were found in June, shortly before the change in hair coat. (P less than 0.05-0.001). The concentrations of K and Na in the bristles deviated functionally from the change in the hair coat. In the first half of the year the bristles of the boars contained significantly more K and Na than in the second half. Values for the elements P, Zn, Fe, Cu, and Mn were subject to great variations through the year. These variations were found to be different with different animals. The influence of endogenic factors on the Mn content of the bristles was particularly striking, also in regard of the order of magnitude. The processes of Mn metabolism in the bristles are obviously still archaic in origin and would thus only allow to make comparison with other values of the mineral content of bristles at the very time of sampling. Differences in the P, Zn, Fe and Cu content of bristles in the different months were, in some instances, statistically significant although variations in the annual mean values were found to be relatively small. 相似文献