COS 12-5 - When biological soil crusts meet Ecological Site Descriptions

Monday, August 7, 2017: 2:50 PM
E145, Oregon Convention Center
Lea A. Condon and David A. Pyke, Forest & Rangeland Ecosystem Science Center, U.S. Geological Survey, Corvallis, OR

Biological soil crusts (BSCs) are a community of organisms that live on the soil surface between perennial plants in arid and semi-arid lands globally. The most macroscopic components of BSCs include lichens and mosses. BSCs contribute to vital ecosystem functions such as nutrient and hydrologic cycling and the prevention of soil erosion. The maintenance of these ecosystem functions is of increasing concern in the Great Basin, however, the distribution of BSCs in the region has been largely unknown, with some questioning if BSCs occur in the Great Basin at all. We use the Assessment, Inventory and Monitoring (AIM) dataset, a randomly located and spatially balanced sampling design, from the Bureau of Land Management to map the presence of lichen and mosses across the region.


Preliminary results demonstrate that both moss and lichen components of BSCs occur throughout the Great Basin ecoregion. Overall, mosses were found on 769 out of 1283 sites. Lichens were found on 374 of those sites. Mosses tended to occur more frequently in the northerly parts of the region. Lichens tended, to occur more frequently within the state of Nevada and extending into western Utah. We are currently working on condensing Ecological Site Descriptions (ESDs) into fewer grouping based on soil, precipitation regimes and vegetation. These grouping will then be related to the occurrence of lichens and mosses. These efforts will lay the groundwork for further refinement of the distribution of BSC species in the region and their association with defined plant communities.