A networking resource devoted to biological soil crusts and the researchers who study them. We will provide a means for international scientists to communicate, share their research, share important news and announcements, ask questions and find collaborators. We will also provide a space for informal writing on research, opinion, and ideas (now seeking posters!).

Friday, October 25, 2013

Biocrusts of Northern Arizona National Monuments Post 5: Sunset Crater National Monument

Typical conditions in Sunset Crater National Monument. a) Landscape view, showing open ponderosa pine forest and cinder-covered interspaces. b) A patch of the moss Ceratodon purpureus associated with organic matter. c) A typical cinder-covered interspace with little soil development.n

Sunset Crater-Soil development at Sunset Crater is rather minimal due to the recent geological origin of the parent materials. Areas with particle size distributions less than 2mm can be found, but are quite rare. Therefore, we did not extend our models to Sunset Crater due to the paucity of biocrust habitat. Survey crews did occasionally observe patches of moss cover, mostly Ceratodon purpureus, often associated with organic matter enrichment (Figure 9b). There was no observation of any cyanobacterial development on these sites, and only very minimal cover of the soil lichen Cladonia (note: rock lichens are quite abundant however). Interestingly, extensive moss cover was observed adjacent to the road possibly due to a N-sloping roadcut.

This is the latest in a series, see here for a lichen key, here for a moss key, here for a description of Walnut Canyon biocrust, here for a description of Wupatki biocrust.

Tuesday, October 22, 2013

Ecological thresholds report

Not exactly biocrust-focused, but biocrusts turn up repeatedly in this report.

Bowker, M.A., Miller, M.E., Belote, R.T., and Garman, S.L., 2013, Ecological thresholds as a basis for defining management triggers for National Park Service vital signs—Case studies for dryland ecosystems: U.S. Geological Survey Open-File Report 2013–1244, 94 p., 



Threshold concepts are used in research and management of ecological systems to describe and interpret abrupt and persistent reorganization of ecosystem properties (Walker and Meyers, 2004; Groffman and others, 2006). Abrupt change, referred to as a threshold crossing, and the progression of reorganization can be triggered by one or more interactive disturbances such as land-use activities and climatic events (Paine and others, 1998). Threshold crossings occur when feedback mechanisms that typically absorb forces of change are replaced with those that promote development of alternative equilibria or states (Suding and others, 2004; Walker and Meyers, 2004; Briske and others, 2008). The alternative states that emerge from a threshold crossing vary and often exhibit reduced ecological integrity and value in terms of management goals relative to the original or reference system. Alternative stable states with some limited residual properties of the original system may develop along the progression after a crossing; an eventual outcome may be the complete loss of pre-threshold properties of the original ecosystem. Reverting to the more desirable reference state through ecological restoration becomes increasingly difficult and expensive along the progression gradient and may eventually become impossible. Ecological threshold concepts have been applied as a heuristic framework and to aid in the management of rangelands (Bestelmeyer, 2006; Briske and others, 2006, 2008), aquatic (Scheffer and others, 1993; Rapport and Whitford 1999), riparian (Stringham and others, 2001; Scott and others, 2005), and forested ecosystems (Allen and others, 2002; Digiovinazzo and others, 2010). These concepts are also topical in ecological restoration (Hobbs and Norton 1996; Whisenant 1999; Suding and others, 2004; King and Hobbs, 2006) and ecosystem sustainability (Herrick, 2000; Chapin and others, 1996; Davenport and others, 1998).

Achieving conservation management goals requires the protection of resources within the range of desired conditions (Cook and others, 2010). The goal of conservation management for natural resources in the U.S. National Park System is to maintain native species and habitat unimpaired for the enjoyment of future generations. Achieving this goal requires, in part, early detection of system change and timely implementation of remediation. The recent National Park Service Inventory and Monitoring program (NPS I&M) was established to provide early warning of declining ecosystem conditions relative to a desired native or reference system (Fancy and others, 2009). To be an effective tool for resource protection, monitoring must be designed to alert managers of impending thresholds so that preventive actions can be taken. This requires an understanding of the ecosystem attributes and processes associated with threshold-type behavior; how these attributes and processes become degraded; and how risks of degradation vary among ecosystems and in relation to environmental factors such as soil properties, climatic conditions, and exposure to stressors. In general, the utility of the threshold concept for long-term monitoring depends on the ability of scientists and managers to detect, predict, and prevent the occurrence of threshold crossings associated with persistent, undesirable shifts among ecosystem states (Briske and others, 2006). Because of the scientific challenges associated with understanding these factors, the application of threshold concepts to monitoring designs has been very limited to date (Groffman and others, 2006). As a case in point, the monitoring efforts across the 32 NPS I&M networks were largely designed with the knowledge that they would not be used to their full potential until the development of a systematic method for understanding threshold dynamics and methods for estimating key attributes of threshold crossings.

This report describes and demonstrates a generalized approach that we implemented to formalize understanding and estimating of threshold dynamics for terrestrial dryland ecosystems in national parks of the Colorado Plateau. We provide a structured approach to identify and describe degradation processes associated with threshold behavior and to estimate indicator levels that characterize the point at which a threshold crossing has occurred or is imminent (tipping points) or points where investigative or preventive management action should be triggered (assessment points). We illustrate this method for several case studies in national parks included in the Northern and Southern Colorado Plateau NPS I&M networks, where historical livestock grazing, climatic change, and invasive species are key agents of change. The approaches developed in these case studies are intended to enhance the design, effectiveness, and management-relevance of monitoring efforts in support of conservation management in dryland systems. They specifically enhance National Park Service (NPS) capacity for protecting park resources on the Colorado Plateau but have applicability to monitoring and conservation management of dryland ecosystems worldwide.

Tuesday, October 15, 2013

Thanks for attending the Biennial Conference for Research on the Colorado Plateau

Posing by the giant french fries sculpture. L to R: Ferran Garcia Pichel, Trent Northen, Ana Giraldo, Blair Steven, Estelle Couradeaux, Jayne Belnap, Yev Marusenko, Aindrila Mukhopadhyay, Anny Chung, Sergio Velasco, Mandy Williams, Eva Robinson, Lindsay Chiquoine, Cheryl McIntyre, Deb Neher, Matt Bowker, Zach Aanderud, Kyle Doherty, Anita Antoninka
Many thanks to all the attendees of our Biocrust session at the Biennial Conference. This year we brought in several new faces and have cemented a strong tradition. I hope to see you all back next time around.

Sunday, October 13, 2013

The charismatic microflora of the desert: the incredible and important natural history of biological soil crusts

For those in the Flagstaff area, I'll be doing a talk about biocrusts for the general public, this Thursday, Oct 17 6:30pm. If you're not familiar with this event, imagine a department seminar with less jargon and more beer. It's fun (kinda wish department seminars were always like this!).

Saturday, October 12, 2013

Tuesday, October 1, 2013