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491.
Igor V. Bartish Wim A. Ozinga Mark I. Bartish G.W. Wieger Wamelink Stephan M. Hennekens Benjamin Yguel Andreas Prinzing 《Conservation biology》2020,34(6):1536-1548
Present biodiversity comprises the evolutionary heritage of Earth's epochs. Lineages from particular epochs are often found in particular habitats, but whether current habitat decline threatens the heritage from particular epochs is unknown. We hypothesized that within a given region, humans threaten specifically habitats that harbor lineages from a particular geological epoch. We expect so because humans threaten environments that dominated and lineages that diversified during these epochs. We devised a new approach to quantify, per habitat type, diversification of lineages from different epochs. For Netherlands, one of the floristically and ecologically best-studied regions, we quantified the decline of habitat types and species in the past century. We defined habitat types based on vegetation classification and used existing ranking of decline of vegetation classes and species. Currently, most declining habitat types and the group of red-listed species are characterized by increased diversification of lineages dating back to Paleogene, specifically to Paleocene-Eocene and Oligocene. Among vulnerable habitat types with large representation of lineages from these epochs were sublittoral and eulittoral zones of temperate seas and 2 types of nutrient-poor, open habitats. These losses of evolutionary heritage would go unnoticed with classical measures of evolutionary diversity. Loss of heritage from Paleocene-Eocene became unrelated to decline once low competition, shade tolerance, and low proportion of non-Apiaceae were accounted for, suggesting that these variables explain the loss of heritage from Paleocene-Eocene. Losses of heritage from Oligocene were partly explained by decline of habitat types occupied by weak competitors and shade-tolerant species. Our results suggest a so-far unappreciated human threat to evolutionary heritage: habitat decline threatens descendants from particular epochs. If the trends persist into the future uncontrolled, there may be no habitats within the region for many descendants of evolutionary ancient epochs, such as Paleogene. 相似文献
492.
Andreas Faludi 《Journal of Environmental Planning and Management》1989,32(1):55-65
This paper is based on one given by Professor Faludi at the Conference on Planning Theory at Torino, Italy in 1986. It answers criticisms of his procedural planning theory voiced by various theorists and enjoined by the authors of the call for papers for the conference. The paper argues that the misgivings voiced by critics have their parallel in ethical theory and develops the view that procedural rationality and utilitarianism share an ethical principle. The paper concludes with a call for an end to sterile debate and an acceptance of different modes of argument. 相似文献
493.
494.
The aim of this study was to investigate the effects of the implementation process to new technologies [e.g. drawing board/computer-aided design (CAD), microfiche/electronic data processing] on the employees concerned. Since the emphasis of the study lay in the intrinsic relationship of the implementation process with stress reactions, the parameters were measured at the place of work in a longitudinal design. Employees (n = 279) in seven companies (work fields: CAD, clerical work, telephone information desk) were tested three times — two months prior to, during, and 12 months after implementation. Aspects of strain and satisfaction were taken into account at each measurement phase. A special test-instrument was designed to describe the ’style of implementation‘ (manner in which implementation took place) particular to each company. The level of strain was found to increase during the implementation process. The amount of this increase was found to correlate with the company's style of implementation as well as with the type of the individual's work activity. The highest levels were found among those employees little included in the implementation process and those whose work is described as monotonous. 相似文献
495.
Cement of the barnacle species, Balanus crenatus, was isolated and separated by SDS-PAGE. Reductive and nonreductive conditions yielded the same result of six major proteins (in the range up to 100 kDa) occurring as two triplets. A third triplet of lower molecular mass was faintly visible. The presence of a reductive agent had only little impact on the solubility of B. crenatus cement. The strong effect of the denaturing conditions (the presence of SDS and the incubation at elevated temperature) on the solubility of the barnacle cement and the absence of disulfide signals in Raman spectra suggest a complex structure of the barnacle cement noncovalently bound. It can be speculated that this protein complex in its quaternary structure is formed by small subunits and is equivalent to the globular cement structures previously detected. 相似文献
496.
497.
Anna Höglhammer Andreas Muhar Patricia Stokowski Thomas Schauppenlehner Renate Eder 《Local Environment》2018,23(8):814-829
Urban public spaces are important areas for leisure, recreation and physical activity and therefore contribute to the quality of life in cities. In particular, for adolescents they provide important spaces to meet with their peers, away from parental or school control. In many cities worldwide, public spaces have undergone severe developmental processes, and often a withdrawal from public space is noted. With regard to the opportunities those spaces provide for adolescents, it is necessary to investigate their current meaning for adolescents in a leisure context. In this article, qualitative research methods were used to investigate factors affecting adolescents’ use of public spaces in Vienna, Austria. In total 45 adolescents were interviewed. Results show that public open spaces are not regarded as important leisure spaces, and data reveal a strong retreat to private areas for leisure purposes. Perceived insecurities and fears support these processes and often result in avoidance of public spaces but also the wish for more control by authorities. 相似文献
498.
Andreas Otto Wagner Gudrun Gstrauntaler Paul Illmer 《Waste management (New York, N.Y.)》2010,30(10):1822-1827
Inocula derived from an anaerobic digester were used to study (i) their potential for methane production and (ii) the utilisation rates of different short chain fatty acids (SCFAs) by the microbial community in defined media with mono-carbon sources (formic-, acetetic-, propionic-, butyric acid) in batch culture. It could be demonstrated that the microbial reactor population could be transferred successfully to the lab, and its ability to build up methane was present even with deteriorating biogas plant performance. Therefore, this reduction in performance of the biogas plant was not due to a decrease in abundance, but due to an inactivity of the microbial community. Generally, the physico-chemical properties of the biogas plant seemed to favour hydrogenotrophic methanogens, as seen by the high metabolisation rates of formate compared with all other carbon sources. In contrast, acetoclastic methanogenesis could be shown to play a minor role in the methane production of the investigated biogas plant, although the origin of up to 66% of methane is generally suggested to be generated through acetoclastic pathway. 相似文献
499.
This study was undertaken to further clarify whether the brown shrimp, Crangon crangon (Linnaeus 1758), is a gonochorist, a facultative or an obligate hermaphrodite. Juvenile shrimps were sampled from intertidal
habitats along the German Wadden Sea coast with a push net and from a power plant water inlet to quantify the share of primary
females. Length-based sex ratios were determined for about 27,000 individuals using external characteristics. Observed sex
ratios were mainly female-biased, and also large males occurred regularly in the catch. This indicates that sex at hatch is
not male as would be characteristic for an obligate protandric hermaphrodite and that not all male shrimps change sex. A cohort-based
computer simulation, including sex-specific growth rates, mortality and seasonally varying recruitment, generated sex ratios
comparable to the field. The observed decline in the proportion of males with increasing size can be explained solely by faster
growth of females without involving hermaphroditism. Based on temperature-dependent growth and moult rates as well as length-specific
numbers of eggs per female, the potential egg production of primary and secondary females was modelled, yielding contributions
of secondary females of <1%. Sex change in C. crangon has previously been observed and may be interpreted as an evolutionary relict of this species having evolved in a habitat
characterized by lower population densities, lower predation levels and increased longevity compared to today’s living conditions
in North Sea coastal waters. 相似文献
500.
Arne Arnberger Wolfgang Haider Renate Eder Andreas Muhar 《Journal of Environmental Planning and Management》2010,53(6):809-825
Depending on gender and activity, overcrowding and safety concerns may detract from urban green space use. Differences in use displacement intentions from a recreational trail in a forest in Vienna were investigated for male and female walkers as well as male and female dog-walkers (N = 425) using an image-based stated preference model. The trail scenarios were depicted as digitally calibrated images that systematically displayed combinations of levels of crowding with different mixes of user types and visitor behaviour. Visitors were asked whether the presented recreation scenario was so unacceptable that they would shift their use away from the presented trail. Hours and days of stated non-use of the recreation trail by various user groups are estimated by integrating the results of the behavioural model with annual visitation data. Use displacement intentions differed by gender and activity. High use levels were a greater concern for all respondents than very low use levels, particularly for female dog-walkers. However, only a small proportion of the recorded hours were heavily used. Safety concerns about very low use levels reduced the potential times of forest use for female walkers without a dog. 相似文献