|Hild, Ann - U OF WYOMING|
Submitted to: Journal of Arid Environments
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 1, 2006
Publication Date: June 1, 2006
Citation: Muscha, J.M., Hild, A.L. 2006. Biological soil crusts in grazed and ungrazed wyoming sagebrush steppe. Journal of Arid Environments 67:195-207. Interpretive Summary: Total biological soil crust cover did not differ inside and outside nine 32-45 year old rangeland exclosures in Wyoming with either the transect or quadrat method. Fruticose lichen cover was higher outside two exclosures using the quadrat method. Species richness was different at our nine sites even though the vegetative community was similar. Current grazing management at our nine sites appears to be maintaining total cover of biological soil crusts. However, species richness may not be recovered. We do not know the potential cover of biological soil crusts at our sites, or how long recovery of cover and richness may take. Additional research of this nature, based on morphological groups of biological soil crusts, is needed to document how rangeland managers can apply this tool to evaluations of rangeland health.
Technical Abstract: Biological soil crusts are regarded as an indicator of healthy landscapes. To understand the response of biological soil crusts to grazing in northern sagebrush steppe, we examined nine Artemisia-dominated sites in Wyoming where livestock have been excluded for 32-45 years. Using two common sampling methods (20 m line transects and 0.25 m2 quadrats) we determined biological soil crust cover and richness inside and outside exclosures. Total biological soil crust cover did not differ inside and outside the exclosures at any of the nine sites, regardless of monitoring method. Cover of biological soil crusts using the transect method ranged from 2-8% inside and 1-6% outside the exclosure. Cover of biological soil crusts using the quadrat method ranged from 2-11% inside and 2-9% outside the exclosure. Fruticose lichen cover was greater outside the exclosure at two sites (Poison Spider and Lander Ant) using the quadrat method. Lichen and moss richness ranged from 5-15 species at each site. Fourteen of the 34 species collected throughout the sites were found only at one site. Our results suggest that grazing removal has not increased biological soil crust cover in the grazed sagebrush steppe sites.