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171.
Matthias Schrter Emilie Crouzat Lisanne Hlting Julian Massenberg Julian Rode Mario Hanisch Nadja Kabisch Julia Palliwoda Jrg A. Priess Ralf Seppelt Michael Beckmann 《Ambio》2021,50(2):289
Conservation efforts are increasingly supported by ecosystem service assessments. These assessments depend on complex multi-disciplinary methods, and rely on a number of assumptions which reduce complexity. If assumptions are ambiguous or inadequate, misconceptions and misinterpretations may arise when interpreting results of assessments. An interdisciplinary understanding of assumptions in ecosystem service science is needed to provide consistent conservation recommendations. Here, we synthesise and elaborate on 12 prevalent types of assumptions in ecosystem service assessments. These comprise conceptual and ethical foundations of the ecosystem service concept, assumptions on data collection, indication, mapping, and modelling, on socio-economic valuation and value aggregation, as well as about using assessment results for decision-making. We recommend future assessments to increase transparency about assumptions, and to test and validate them and their potential consequences on assessment reliability. This will support the taking up of assessment results in conservation science, policy and practice.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01379-9) contains supplementary material, which is available to authorized users. 相似文献
172.
Paul Braunger Hermann Frank Christian Korunka Manfred Lueger Bettina Kubicek 《International journal of occupational safety and ergonomics》2013,19(1):143-155
This paper attempts to replicate a safety climate model originally tested in Australia to assess its applicability in a different context: namely, across production workers in 22 medium-sized metal processing organizations in Austria. The model postulates that safety knowledge and safety motivation mediate the relation between safety climate on the one hand and safety compliance and participation on the other. Self-report data from 1075 employees were analyzed using structural equation modeling (SEM). The results of the replication study largely confirmed the original safety climate model. However, in addition to indirect effects, direct links between safety climate and actual safety behavior were found. 相似文献
173.
Yinhe Liu Manfred Geier Alejandro Molina Christopher R. Shaddix 《International Journal of Greenhouse Gas Control》2011
The coal stream ignition process is critical to the performance of modern pulverized coal burners, particularly when operating under novel conditions such as experienced in oxy-fuel combustion. However, experimental studies of coal stream ignition are lacking, and recent modeling efforts have had to rely on comparisons with a single set of experiments in vitiated air. To begin to address this shortfall, we have conducted experiments on the ignition properties of two U.S. and two Chinese coals in a laminar entrained flow reactor. Most of the measurements focused on varying the coal feed rate for furnace temperatures of 1230–1320 K and for 12–20 vol.% O2 in nitrogen. The influence of coal feed rate on ignition with a carbon dioxide diluent was also measured for 20 vol.% O2 at 1280 K. A second set of measurements was performed for ignition of a fixed coal feed rate in N2 and CO2 environments at identical furnace temperatures of 1200 K, 1340 K, and 1670 K. A scientific CCD camera equipped with a 431 nm imaging filter was used to interrogate the ignition process. Under most conditions, the ignition delay decreased with increasing coal feed rate until a minimum was reached at a feed rate corresponding to a particle number density of approximately 4 × 109 m?3 in the coal feed pipe. This ignition minimum corresponds to a cold flow group number, G, of ~0.3. At higher coal feed rates the ignition delay increased. The ignition delay time was shown to be very sensitive to (a) the temperature of the hot coflow into which the coal stream is introduced, and (b) the coal particle size. The three high volatile bituminous coals showed nearly identical ignition delay as a function of coal feed rate, whereas the subbituminous coal showed slightly greater apparent ignition delay. Bath gas CO2 content was found to have a minor impact on ignition delay. 相似文献
174.
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176.
Antonella Soro Manfred Ayasse Marion U. Zobel Robert J. Paxton 《Behavioral ecology and sociobiology》2011,65(4):641-653
The ability to discriminate degrees of relatedness may be expected to evolve if it allows unreciprocated altruism to be preferentially
directed towards kin (Hamilton in J Theor Biol 7:1–16, 1964). We explored the possibility of kin recognition in the primitively eusocial halictid bee Lasioglossum malachurum by investigating the reliability of worker odour cues that can be perceived by workers to act as indicators of either nest
membership or kinship. Cuticular and Dufour’s gland compounds varied significantly among colonies of L. malachurum, providing the potential for nestmate discrimination. A significant, though weak, negative correlation between chemical distance
and genetic relatedness (r = −0.055, p < 0.001) suggests a genetic component to variation in cuticular bouquet, but odour cues were not informative enough to discriminate
between different degrees of relatedness within nests. This pattern of variation was similar for Dufour’s gland bouquets.
The presence of unrelated individuals within nests that are not chemically different from their nestmates suggests that the
discrimination system of L. malachurum is prone to acceptance errors. Compounds produced by colony members are likely combined to generate a gestalt colony chemical
signature such that all nestmates have a similar smell. The correlation between odour cues and nest membership was greater
for perceived compounds than for non-perceived compounds, suggesting that variability in perceived compounds is a result of
positive selection for nestmate recognition despite potentially stabilising selection to reduce variability in odour differences
and thereby to reduce costs derived from excessive intracolony nepotistic behaviour. 相似文献
177.
Katia Ballorain Stéphane Ciccione Jérôme Bourjea Henri Grizel Manfred Enstipp Jean-Yves Georges 《Marine Biology》2010,157(12):2581-2590
We investigated the habitat use in green turtles exploiting a 13-ha multispecific seagrass meadow at Mayotte Island, south-western
Indian Ocean. A phyto-ecological survey shows the occurrence of eight seagrass species, dominated by Halodule uninervis and Syringodium isoetifolium, distributed according to four distinct seagrass communities along the depth gradient. Direct underwater censuses show that
green turtles occurred all over the meadow. Yet when community relative surface area was taken into account green turtles
preferentially frequented the most seaward, biomass-richer S. isoetifolium-dominated community, suggesting that green turtles compensate for their intrinsically nutrient-poor herbivorous diet. Additionally,
smaller (<80 cm standard curved carapace length, SCCL) individuals also preferentially occurred in the most shoreward H. univervis-dominated community where no larger (>80 cm SCCL) individuals were sighted, suggesting habitat use is indicative of diet
selection and may reflect size-specific food requirements and physiology. 相似文献
178.
Environmental impact of historical harbour city Zadar (Croatia) on the composition of marine sediments and soils 总被引:4,自引:0,他引:4
Large amounts of oyster shells are produced as a by-product of shellfish farming in coastal regions without beneficial use
options. Accordingly, this study was conducted to evaluate the potential for the use of waste oyster shells (WOS) containing
a high amount of CaCO3 to improve soil quality and to stabilize heavy metals in soil. To accomplish this, an incubation experiment was conducted
to evaluate the ability of the addition of 1–5 wt% WOS to stabilize the Pb (total 1,246 mg/kg) and Cd (total 17 mg/kg) in
a contaminated soil. The effectiveness of the WOS treatments was evaluated using various single extraction techniques. Soil
amended with WOS was cured for 30 days complied with the Korean Standard Test method (0.1 M·HCl extraction). The Pb and Cd
concentrations were less than the Korean warning and countermeasure standards following treatment with 5 wt% WOS. Moreover,
the concentrations of Cd were greatly reduced in response to WOS treatment following extraction using 0.01 M·CaCl2, which is strongly associated with phytoavailability. Furthermore, the soil pH and exchangeable Ca increased significantly
in response to WOS treatment. Taken together, the results of this study indicated that WOS amendments improved soil quality
and stabilized Pb and Cd in contaminated soil. However, extraction with 0.43 M·CH3COOH revealed that remobilization of heavy metals can occur when the soil reaches an acidic condition. 相似文献
179.
180.
Johanna?Chemnitz Nadiia?Bagrii Manfred?Ayasse Sandra?SteigerEmail author 《Die Naturwissenschaften》2017,104(7-8):53
Life history theory predicts a trade-off between male sexual trait expression and immunocompetence. Using burying beetles, Nicrophorus vespilloides, as a model, we investigated the relationship between male immune function, sex pheromone emission, and attractiveness under field conditions. In the first experiment, we tested whether there is a positive correlation between immune capacity, sex pheromone characteristics (quantity, relative composition, and time invested in pheromone emission), and male attractiveness. As a measurement of immune capacity, we used an individual’s encapsulation ability against a novel antigen. In the second experiment, we specifically examined whether a trade-off between chemical trait expression and immune function existed. To this end, we challenged the immune system and measured the subsequent investment in sex pheromone emission and the attractiveness of the male under field conditions. We found that a male’s immunocompetence was neither related to the emission of the male’s sex pheromone nor to its attractiveness in the field. Furthermore, none of the immune-challenge treatments affected the subsequent investment in pheromone emission or number of females attracted. However, we showed that the same males that emitted a high quantity of their sex pheromone in the laboratory were able to attract more females in the field. Our data suggest that the chemical signal is not a reliable predictor of a male’s immunocompetence but rather is a general important fitness-related trait, with a higher emission of the sex pheromone measured in the laboratory directly affecting the attractiveness of a male under field conditions. 相似文献