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Abstract: Species occurrence in a habitat patch depends on local habitat and the amount of that habitat in the wider landscape. We used predictions from empirical landscape studies to set quantitative conservation criteria and targets in a multispecies and multiscale conservation planning effort. We used regression analyses to compare species richness and occurrence of five red‐listed lichens on 50 ancient oaks (Quercus robur; 120–140 cm in diameter) with the density of ancient oaks in circles of varying radius from each individual oak. Species richness and the occurrence of three of the five species were best explained by increasing density of oaks within 0.5 km; one species was best explained by the density of oaks within 2 km, and another was best predicted by the density of oaks within 5 km. The minimum numbers of ancient oaks required for “successful conservation” was defined as the number of oaks required to obtain a predicted local occurrence of 50% for all species included or a predicted local occurrence of 80% for all species included. These numbers of oaks were calculated for two relevant landscape scales (1 km2 and 13 km2) that corresponded to various species responses, in such a way that calculations also accounted for local number of oaks. Ten and seven of the 50 ancient oaks surveyed were situated in landscapes that already fulfilled criteria for successful conservation when the 50% and 80% criteria, respectively, were used to define the level of successful conservation. For cost‐efficient conservation, oak stands in the landscapes most suitable for successful conservation should be prioritized for conservation and management (e.g., grazing and planting of new oaks) at the expense of oak stands situated elsewhere.  相似文献   
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Abstract

Methoxychlor was found to be sufficiently persistant in soil and its residues were present even 18 months after the soil treatment. Saprophytes, fungi and actinomyces were unaffected by varying concentrations of methoxychlor, azotobacter however was susceptable. Soil strains isolated did not utilize methoxychlor as a sole carbon source except for 9 cultures belonging to the genera Bacillus, Acineto‐bacter and Rhodococcus which carried out the complete dechlorination, demethylation and splitting of one of methoxychlor aromatic rings. Anaerobic conditions were more favorable for methoxychlor biodegradation by soil and pure microbial cultures.  相似文献   
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Groups involved in the livestock vs large carnivore conflict hold widely divergent attitudes toward carnivores, yet they all endorse general ecocentric values. The hypothesis that contrasting motives for the endorsement of ecocentric values may mediate between the general values and attitudes toward carnivores was evaluated in a survey among sheep farmers, wildlife managers, and research biologists in Norway. Results showed positive associations between anthropocentrism and negative attitudes toward carnivores, and between ecocentrism and positive attitudes toward carnivores for all three groups. Farmers, relative to the other groups, scored lowest on the ecocentric and highest on the anthropocentric subscales, as operationalized by Thompson and Barton (1994). This result may be interpreted within a cognitive hierarchy model where environmental beliefs may transform general ecocentric values into negative or positive attitudes toward one specific environmental category.  相似文献   
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Methoxychlor was found to be sufficiently persistent in soil and its residues were present even 18 months after the soil treatment. Saprophytes, fungi and actinomyces were unaffected by varying concentrations of methoxychlor, azotobacter however was susceptable. Soil strains isolated did not utilize methoxychlor as a sole carbon source except for 9 cultures belonging to the genera Bacillus, Acinetobacter and Rhodococcus which carried out the complete dechlorination, demethylation and splitting of one of methoxychlor aromatic rings. Anaerobic conditions were more favorable for methoxychlor biodegradation by soil and pure microbial cultures.  相似文献   
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