Biological soil crusts (biocrusts) are the coolest thing that most people have never heard of. They are a soil surface assemblage of many different organisms including but not limited to cyanobacteria, fund, mosses and lichens in any combination. The defining characteristic is that they hold together the uppermost millimeters of mineral soil in a cohesive layer - a crust. You can find them throughout the world in places where sufficient light can reach the soil surface for these photosynthetic soils to operate. Because dense cover of plants shades out these communities, they are typically found in the dry and/or cold parts of the world where vascular plant cover is limited.
These organisms are desiccation tolerant. This means almost all of the water can evaporate out of their bodies, but they remain alive. Take a second to reflect on how AMAZING that is! When it does rain, they can rehydrate and are ready for action again. Check out the rehydration of these desiccation tolerant biocrust mosses in this video by Kyle Doherty.
Another of the most interesting things about them is their multi functionality. Since they hold soil particles together, they protect soils from erosion. Like plants, they fix and store carbon. Like most soil communities they also decompose organic matter and cycle nutrients. Biocrusts harbor N-fixing species too, and strongly influence the fate of rainfall by dictating infiltration and runoff rates. All of this function can be easily lost because soil disturbances can degrade them quickly, and their recovery after disturbance can be slow, at least in some ecosystems.
I (Matt) have been studying these communities since the late 1990's as an undergraduate. At the time, it seemed like an important topic that too few people were actively working on. Since that time, biocrusts have taken me to various locations in the United States, Spain, and Australia and I have addressed topics as diverse as reproductive ecology, distribution, physiology, biodiversity, multi functionality and restoration of biocrusts. Their importance drew me to them, but they have been an endless well of fascination for me ever since.
These are some of the specific themes and projects we have going.
Biocrust synthesis working group (J.W. Powell Center)
Desiccation & diversity in dryland mosses (3-D Moss)
Restoration of biological soil crusts (biocrusts)
NAU is a hotspot for forest ecological restoration research, mostly focusing on restoring natural low-intensity fires to forested landscapes to avoid stand-destroying fire. Yet, stand-destroying fires still occur nearly every year in the region and we have a need for development of new restoration techniques. Enter the mosses....a special kind of biocrust, composed entirely of ruderal mosses can be prevalent in the post forest fire landscape and enhance ecosystem function.
Role of mosses in post-forest fire restoration
Mycorrhizal ecology & Plant-Soil feedbacks
Plants are adapted to multiple aspects of their environment including the climate, the physico-chemical soil environment, and the soil biota (including symbionts such as mycorrhizal fungi). As climates change plants are experiencing novel environments that may differ slightly to strongly from their evolutionary environment. Every time we move plant materials somewhere (e.g. seeding) the resultant plants experience novel environments. This line of our research is aimed at determining which of three elements of the novel environment is the most influential to plant success: the climate, the soil, the soil biota. It is imperative to conduct this basic research to inform assisted migration, planting/seeding for restoration, or any application in which plant materials are imported.
Role of soil organisms in response of plants to novel environments
Effects of biochar on Arizona crop yield and water holding capacity
Unique plant communities of Southern Colorado Plateau Nationals Parks and Monuments