Survey of the Algae, Lichens, and Mosses of Microbiotic Crusts in Selected Semiarid and Arid Sites in Western North America

微生物土壤结皮是蓝藻、真核藻类、真菌、地衣和苔藓植物的组合，在健康的半干旱和干旱生态系统中起着重要作用。尽管它们具有突出的生态作用，但对微生物结壳的物种组成缺乏明确的认识。在为期36个月的时间里，我们将在北美西部山间地区、代表不同气候和地质区域的30个已知成熟微生物外壳群落的地点进行采样，以便：(1)表征微生物外壳生物的物种组成。这包括在采样的微生物外壳中发现的蓝藻、真核藻类、地衣和苔藓的物种清单和可能遇到的新物种的描述；(2)建立一个数据库，其中包括物种列表、描述、图像和关于每个地点土壤物理和化学特征的信息；(3)制作可在万维网上查阅的数据库电子版本；(4)存档土壤样本，作为对调查中未包括的生物感兴趣的生物学家的资源；(5)确定生物多样性高的地点，进行更深入的研究。这个项目是第一个对微生物外壳生物的全面研究，因此它将提供一个资源和数据库，在项目完成后的许多年里，可能会对生态学家、系统学家和牧场管理者有用。

9870201 Johansen Microbiotic soil crusts are assemblages of cyanobacteria, eukaryotic algae, fungi, lichens, and bryophytes that play an important role in healthy semiarid and arid ecosystems. Despite their prominant ecological role, a clear understanding of the species composition of microbiotic crusts is lacking. Over the course of a 36-month period, thirty locations with known mature microbiotic crust communities throughout intermountain western North America, and representing diverse climatic and geological regions, will be sampled in order to: (1) characterize the species composition of the microbiotic crust organisms. This includes an inventory of the species of cyanobacteria, eukaryotic algae, lichens, and mosses found in the sampled microbiotic crusts and descriptions of new species that may be encountered; (2) produce a data base that includes species lists, descriptions, images, and information on the physical and chemical characteristics of the soils at each locality; (3) produce an electronic version of the data base that will be accessible on the World Wide Web; (4) archive soil samples that will serve as a resource to biologists interested in organisms not included in the survey; (5) identify locations of high diversity that should be targeted for more in-depth study. This project is the first comprehensive study of microbiotic crust organisms, and as such it will provide a resource and database that potentially will be of use to ecologists, systematists, and rangeland managers for many years after the completion of the project.