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91.
Ecological restoration centers on the reestablishment of ecological processes and the integrity of degraded ecosystems, but its success also depends on public acceptance and support. In this study, we evaluated the short‐term ecological effects of different restoration treatments in Iceland. Furthermore, we tested the public perception of aesthetic and recreational values of these revegetated areas. Predefined soil and vegetation indicators were measured, and a survey, based on a questionnaire and photographs of the different areas, was used for gauging public perception. Our results indicate that different restoration treatments triggered different succession trajectories. The vegetation composition of areas seeded with grasses seemed to be on a trajectory toward relatively undisturbed reference ecosystems, whereas areas seeded with nonnative lupine seemed to be developing a novel ecosystem. Results of the survey demonstrated that people valued the appearance of revegetated areas higher than that of the eroded control areas, with the exception of areas seeded with lupine. The visual perception of each restoration treatment corresponded well with the ecological factors and revealed both a social and an ecological rationale against the use of lupine in land restoration. The results indicate that the design of restoration projects should be based on both an analysis of sociocultural priorities and an understanding of possible trajectories of ecosystem development associated with the available restoration methods to avoid results that are neither socially acceptable nor ecologically feasible. 相似文献
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93.
Dalsgaard Gudmundsdóttir Helgason Høie Thoresen Wichardt & Wiklund 《Journal of applied microbiology》1998,84(6):999-1006
The atypical isolates of Aeromonas salmonicida are becoming increasingly important as the frequency of isolation of bacteria belonging to this group continues to rise. The primary object of this study was to compare and evaluate the results obtained in various laboratories concerning the biochemical identification of atypical Aer. salmonicida before and after standardization of media and methods. Five laboratories examined 25 isolates of Aer. salmonicida from diverse fish species and geographical locations including the reference strains of Aer. salmonicida subsp. salmonicida (NCMB 1102) and Aer. salmonicida subsp. achromogenes (NCMB 1110). Without standardization of the methods, 100% agreement was obtained only for two tests: motility and ornithine decarboxylase. The main reason for the discrepancies found was the variation of the incubation time prior to reading the biochemical reactions. After standardization, improvement was obtained with the identification; however, disagreement was still observed between the different laboratories. These findings demonstrate the difficulties involved in a proper identification of atypical Aer. salmonicida and also that data presented in the literature on various strains of Aer. salmonicida are not readily comparable. This paper seems to be the first on standardization of microbiological tests for identification of fish pathogens and the results obtained show the need for standardization of methods both within and between laboratories. 相似文献