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We analyze the status of the Angel de la Guarda deer mouse (Peromyscus guardia), a species endemic to Mexico, based on our own fieldwork, bibliographic records and information from colleagues. This species, with different subspecies on three islands and a population of an undetermined subspecies on a fourth, was apparently common until the mid-1960s. Currently the species is critically endangered, if not already extinct. One of the subspecies and the undetermined population are presumed extinct. Of the two other subspecies, one is at least in critical condition, and the other at least reduced. The demise of the species can be attributed to the introduction of domestic cats. The case of P. guardia is a good example of the vulnerability of other taxa of endemic rodents on islands in the Gulf of California. 相似文献
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[目的]为广东省选择和应用优良水生植物提供参考。[方法]对广东省珠三角的广州、东莞、深圳3个城市的植物园或公园的草本水生植物的外部形态进行调查和感观鉴定,然后运用层次分析法软件进行分析、建模、排序。[结果]有花草本挺水型水生植物分值在5．9000分以上的是：千屈菜（LythrumsalicariaL．）、田葱（PhilydrumlanuginosumRanks）、白花千屈菜（L．salicariaCV．whiteflower）、水葱（ScirpusvalidusVahl）、灯心草（JuwweffususL．）、小香蒲（TyphaminimaFunk）、睡莱（MenyantehestrifoliaL．）、东方泽泻『Alismaorientale（Sam．）Juzep．]、双色美人蕉（Cannawarscewieziiev．PurpleStripe）、泽泻[Alilsmaorientale（Samuel．）Jez．]。有花非挺水型水生植物的分值在5．9000分以上是：莼菜（BraseniaschreberiJ．F．Gmel）、莲（NelumbonuciferaGaertn）、墨西哥睡莲『NymphaeamexicanaZuccarini]、萍逢草[Nupharvumilum（Timm．）DC．][结论]在水景设计中可以优先选择分值较高的草本水生植物种类． 相似文献
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《Journal of Sustainable Forestry》2013,32(1):17-28
Abstract Mexican forestry science has been affected by its relationship with the Mexican state, and by the history of state forestry institutions. Conflicts between conservationists and politicians engaged in land reform resulted in loss of power for conservationists in the forest department in the 1940s. More recent political struggles for control of the forests color the interpretations which forest communities and foresters place upon forest management practices, and may lead to present day debates over specific silvicultural practices. If foresters are to apply silvicultural techniques, they need to be aware of the political experience of the landowners they work for, and the political implications of their own technical knowledge. 相似文献
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