Post-doc job announcement in Barger Lab, University of Colorado Boulder

Post-Doctoral Research Associate – University of Colorado Boulder – Department of Ecology and Evolutionary Biology

A two-year post-doctoral research associate position will be available in Nichole Barger’s lab at the University of Colorado – Boulder. The successful candidate will work on a newly funded project to examine plant and soil responses to biological soil crust restoration. The post-doctoral research associate will oversee field research at Hill Air Force Base in the Great Basin and Jornada Experimental Range in the Chihuahuan Desert. This work will occur in close collaboration with an interdisciplinary team of scientists who specialize in soil microbiology (Ferran Garcia-Pichel, Arizona State University), soil ecology (Matthew Bowker, Northern Arizona University and Jayne Belnap USGS), ecosystem ecology (Sasha Reed, USG) and soil science (Mike Duniway, USGS).  We are seeking a highly motivated and energetic applicant with specialties in ecosystem ecology/biogeochemistry, plant ecology, or soil ecology. Expertise in aridland ecology is a plus.  The start date is flexible ranging from December 2014 through February 2015. If you are interested please send a brief letter of interest and a current CV to Nichole Barger at nichole.barger@colorado.edu.

Biocrusts in El Malpais National Monument, New Mexico

It's that time again…photo dumps from trips taken months ago! Last Spring I joined my graduate student Jesse, and two collaborators from the National Park Service on a trip to El Malpais in New Mexico.  Jesse is working on establishing an array of monitoring plots for "unique plant communities" which are important reservoirs of biodiversity in the National Park System. 

El Malpais is a National Monument built around a series of lava flows. One cool thing about it is that the lava flows left islands of pre-existing soils. Because much of the lava is a'a, its is very difficult to traverse. The Monument resource manager, David Hayes told us there were 2 kinds of people who work at the Monument: 1. those who have hurt themselves on the lava, 2. those that will hurt themselves on the lava. This works for cows too, so the islands or "kipukas" have experienced much less disturbance historically. So in addition to selecting unique plant communities to sample, I was very intrigued to see what the biocrusts looked like in the kipukas. I had envisioned some kind of sandy soils with grasslands or woodlands. Instead, the soils were derived of older basalt, and sure enough there were plenty of biocrusts. There are a ton of places, especially in the Great Basin and Colombia Basin where basalt soils support biocrusts. But for some reason, despite much looking, I have never seen biocrusts on basalt soils on the Colorado Plateau…until El Malpais. From that moment on, I was hopelessly fascinated to see more soils. In addition to lava of different ages, there are sedimentary rocks which develop into very different soils with very different communities. Very cool place.

Maybe the coolest thing I learned was from Jesse. A Navajo story recounts the monster killing exploits of the hero twins. One of the monsters they killed was walking giant. The lava flows are the blood of walking giant. 

Appears to be a Leptogium, anyone able to ID from the picture?

Collema tenax and a Placidium species growing together as they often do.

Collema coccophorum; note the slightly reddish disks are apothecia.

A Psora species, probably globifera.

The lava flows are riddled with lava tubes. When lava is flowing the exterior may begin to harden, while the center is still liquid and able to drain out leaving tubes.

Inside a tube!

Colorado Arts & Sciences Magazine: Can biological soil crust communities be restored?

Nice, recent article on our biocrust restoration project on military lands (led by Nichole Barger with a team consisting of Ferran Garcia-Pichel, Ana Giraldo, Sergio Velasco, myself, Anita Antoninka, Jayne Belnap, Sasha Reed, & Mike Duniway) here.

Ana Giraldo tending her cyanobacterial cultures in the Garcia-Pichel lab (Arizona State University)

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., 

http://pubs.usgs.gov/of/2013/1244/

Introduction

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.