Taxonomic Considerations in Listing Subspecies Under the U.S. Endangered Species Act

Abstract:  The U.S. Endangered Species Act (ESA) allows listing of subspecies and other groupings below the rank of species. This provides the U.S. Fish and Wildlife Service and the National Marine Fisheries Service with a means to target the most critical unit in need of conservation. Although roughly one-quarter of listed taxa are subspecies, these management agencies are hindered by uncertainties about taxonomic standards during listing or delisting activities. In a review of taxonomic publications and societies, we found few subspecies lists and none that stated standardized criteria for determining subspecific taxa. Lack of criteria is attributed to a centuries-old debate over species and subspecies concepts. Nevertheless, the critical need to resolve this debate for ESA listings led us to propose that minimal biological criteria to define disjunct subspecies (legally or taxonomically) should include the discreteness and significance criteria of distinct population segments (as defined under the ESA). Our subspecies criteria are in stark contrast to that proposed by supporters of the phylogenetic species concept and provide a clear distinction between species and subspecies. Efforts to eliminate or reduce ambiguity associated with subspecies-level classifications will assist with ESA listing decisions. Thus, we urge professional taxonomic societies to publish and periodically update peer-reviewed species and subspecies lists. This effort must be paralleled throughout the world for efficient taxonomic conservation to take place.     

船舶噪声污染与控制

船舶噪声的污染源主要是由于船舶动力装置及其他辅助装置自身振动及吸排气引起的。通过实验对比对各类噪声进行了分析研究，提出了通过声源控制来降低船舶噪声级大小的措施。     

"长苞铁杉和铁杉属数量分类的研究"之评注

邹惠渝和张凤春两位先生所撰写的"长苞铁杉和铁杉属数量分类的研究"一文(见<南京林业大学学报>,1996,20(1)43～47),至少存在以下3个问题值得商榷一是取材欠完整,二是聚类方法单一,三是结合线计算错误.据本文重新核算,<邹文>的结论有误.     

DNA条形码技术在水生生物分类中的研究进展

介绍DNA条形码技术的相关原理和发展概况,分析其具有的优势和所存在的局限性,并阐述了DNA条形码技术在水生生物分类中的研究现状,最后探讨了目前存在的问题并展望了其未来应用前景.     

Taxonomic Exaggeration and Its Effects on Orchid Conservation

Abstract:  Orchids are the largest family of flowering plants, encompassing several times as many species as birds or mammals. Because of their diversity, charisma, and threats from overcollection and habitat loss, they are a key group in conservation. Nevertheless, preservation of this group is plagued by taxonomic problems, particularly in Europe, where new taxa are actively being described. We used a checklist of orchids to compare the taxonomic treatment of this family between Europe and neighboring areas to search for geographical patterns. Numbers of invalid, infraspecific, and hybrid names are significantly higher in Europe than in surrounding areas. Recognition of numerous and poorly circumscribed orchid taxa is a serious obstacle to their conservation because rare, poorly defined species may be prioritized for conservation over taxonomically "good" species. This phenomenon may be the result of the popularity of orchids in Europe. We believe that more taxonomic effort should be made in other areas of the world (e.g., the tropics) and on less charismatic groups.     

Vascular plant extinction in the continental United States and Canada

Extinction rates are expected to increase during the Anthropocene. Current extinction rates of plants and many animals remain unknown. We quantified extinctions among the vascular flora of the continental United States and Canada since European settlement. We compiled data on apparently extinct species by querying plant conservation databases, searching the literature, and vetting the resulting list with botanical experts. Because taxonomic opinion varies widely, we developed an index of taxonomic uncertainty (ITU). The ITU ranges from A to F, with A indicating unanimous taxonomic recognition and F indicating taxonomic recognition by only a single author. The ITU allowed us to rigorously evaluate extinction rates. Our data suggest that 51 species and 14 infraspecific taxa, representing 33 families and 49 genera of vascular plants, have become extinct in our study area since European settlement. Seven of these taxa exist in cultivation but are extinct in the wild. Most extinctions occurred in the west, but this outcome may reflect the timing of botanical exploration relative to settlement. Sixty-four percent of extinct plants were single-site endemics, and many occurred outside recognized biodiversity hotspots. Given the paucity of plant surveys in many areas, particularly prior to European settlement, the actual extinction rate of vascular plants is undoubtedly much higher than indicated here.     

Antibiotic resistome mostly relates to bacterial taxonomy along a suburban transmission chain

• The α-diversities of resistome were lower in manure and compost than in soils. • There were significant correlations between the resistome and bacterial taxonomy. • Bacterial taxonomy was the highest in explaining resistome variances. Antibiotic resistance genes comprising antibiotic resistome are of great concern due to their increase in the environment. Recent evidence of shared resistomes between soils and animal husbandry has imposed potential risks to human health. However, the correlation between a given community’s resistome and bacterial taxonomic composition is controversial. Here, a transmission chain of resistomes from swine manure to compost and compost-amended soil were analyzed in five suburban areas of Beijing, China, with unamended agricultural soils as control soils. Antibiotic resistomes and bacterial taxonomic compositions were distinct between (I) manure and compost; and (II) compost-amended and control soils. In manure, compost, and compost-amended soils, the β-diversity of the resistome and bacterial taxonomic composition was significantly correlated, while no correlation was detected in control soils. Bacterial taxonomic composition explained 36.0% of total variations of the resistome composition, much higher than environmental factors. Together, those results demonstrated that antibiotic resistome was closely related to bacterial taxonomic composition along the suburban transmission chain.