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581.
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Combining geodiversity with climate and topography to account for threatened species richness
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Understanding threatened species diversity is important for long‐term conservation planning. Geodiversity—the diversity of Earth surface materials, forms, and processes—may be a useful biodiversity surrogate for conservation and have conservation value itself. Geodiversity and species richness relationships have been demonstrated; establishing whether geodiversity relates to threatened species’ diversity and distribution pattern is a logical next step for conservation. We used 4 geodiversity variables (rock‐type and soil‐type richness, geomorphological diversity, and hydrological feature diversity) and 4 climatic and topographic variables to model threatened species diversity across 31 of Finland's national parks. We also analyzed rarity‐weighted richness (a measure of site complementarity) of threatened vascular plants, fungi, bryophytes, and all species combined. Our 1‐km2 resolution data set included 271 threatened species from 16 major taxa. We modeled threatened species richness (raw and rarity weighted) with boosted regression trees. Climatic variables, especially the annual temperature sum above 5 °C, dominated our models, which is consistent with the critical role of temperature in this boreal environment. Geodiversity added significant explanatory power. High geodiversity values were consistently associated with high threatened species richness across taxa. The combined effect of geodiversity variables was even more pronounced in the rarity‐weighted richness analyses (except for fungi) than in those for species richness. Geodiversity measures correlated most strongly with species richness (raw and rarity weighted) of threatened vascular plants and bryophytes and were weakest for molluscs, lichens, and mammals. Although simple measures of topography improve biodiversity modeling, our results suggest that geodiversity data relating to geology, landforms, and hydrology are also worth including. This reinforces recent arguments that conserving nature's stage is an important principle in conservation. 相似文献
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Challenges companies face and tools they use to identify and reduce their environmental footprints across their supply chains 相似文献
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Colombo Stefanie M. Rodgers Timothy F. M. Diamond Miriam L. Bazinet Richard P. Arts Michael T. 《Ambio》2020,49(4):865-880
Ambio - Docosahexaenoic acid (DHA) is an essential, omega-3, long-chain polyunsaturated fatty acid that is a key component of cell membranes and plays a vital role in vertebrate brain function. The... 相似文献
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After the Great East Japan Earthquake in March 2011, numerous evacuees had to stay in evacuation shelters such as school gymnasiums. In general, after a disaster, ensuring the safety and security of evacuees in evacuation shelters is a serious problem. Consequently, many of these evacuees feared that they would be victims of crime in the shelters or that their evacuated homes would be burgled. To examine what factors evoke a general fear of crime in shelters and burglary of evacuated homes, we conducted an online questionnaire on 300 evacuees in Miyagi Prefecture who had stayed at such shelters. From a factor analysis of fear of 16 specific kinds of crime in shelters, we extracted two factors representing fear of property and female-related crime. We then found that a general fear of crime in shelters was associated with being young and a fear of female-related crime, while a fear of burglary of evacuated homes was associated with being female, owning a detached house, and fear of property crime. Based on these results, we provide recommendations aiming to help reduce the fear of crime in shelters and burglary of evacuated homes. 相似文献
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Richard E Plant Marc Mangel Lawrence E Flynn 《Journal of Environmental Economics and Management》1985,12(1):45-61
The problem of selecting a pesticide application strategy in the face of increasing resistance to the pesticide in the pest population is dealt with. The grower in this situation may do better by sacrificing a portion of the present crop in return for a reduced resistance to future applications. The model presented represents an attempt to forge a compromise between excessive complexity, rendering the model difficult to study, and excessive simplicity, rendering the model useless. The effects of timing of the application of the pesticide within the season are discussed. The principle conclusions are the following: (i) If immigration of pests from refugia is significant then proper timing of the application of pesticide may be used to help alleviate resistance growth. (ii) Resistance growth may best be reduced by spraying earlier than what would otherwise be the best time. (iii) The value of the discount rate (and of the time horizon) has a profound effect on the nature of the optimal policy. 相似文献
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