The term biological soil crust (or biocrust) encompasses the diverse community of moss, algae, lichens, and cyanobacteria living within the top inch of soil. Biocrusts form in all terrestrial ecotypes, but people often overlook them in favor of larger species. Biocrusts stabilize the soil by aggregation, reducing erosion. They increase soil fertility by enhancing nutrient cycling. A healthy biocrust increases infiltration and plays a role in succession towards a diverse and functioning ecosystem. They are especially important in arid and semi-arid ecosystems.
Towards the goal of restoring land to healthy ecosystem function, we consider all facets of the land, not just the vascular plants that may inhabit it. Unaided, biocrusts may take from decades to a century to reestablish after degradation. We would like to determine the most effective and practical methods to restore biological soil crusts.
Research and updates found here include projects on moss, lichens, and biocrust as we delve into this charismatic and important part of the ecosystem.
Plants live in tight association with microbes, especially belowground where fungi and bacteria live on and inside the roots of plants. The relationship can be beneficial or harmful to the plant. Some microbes cause plant diseases by decomposing roots. Others trade nutrients with the roots in return for sugars produced aboveground by leaves.
We investigate two main aspects of the relationship between plants and microbes in the soil. First, as it pertains to weeds, we want to know if soil microbes can help or hinder plant invasions. Three highly invasive weeds of contrasting life history strategies; cheatgrass, knapweed and leafy spurge, co-occur with remnants of native plant vegetation. This creates a unique opportunity to observe, characterize, and manipulate interactions between plants and belowground microbial communities. We outline a number of short, intermediate and long-term research projects that will significantly enhance our knowledge regarding plant microbe interactions and soil processes, with the overall goal to better understand, predict and counteract plant invasions, and to restore and manage invaded ecosystems.
Second, we seek to understand how the relationship between plants and soil influences the function of ecosystem processes. Soil microbes are responsible for organic matter decomposition and nutrient cycling between the atmosphere and the land. On this project we collaborate with the Earth Microbiome Project (EMP). The goal is to map and understand the diversity of microorganisms in habitats around the world. We mapped microbial diversity and function across gradients of weed invasions.
Rebecca Durham's field note shows a nascent yellowbell, low pussytoes budding, and brown crustose lichen.
02-26-15 Field Note
05-01-15 Phenology Field Note