Biological soil crusts (biocrust) are communities of lichen, moss, and cyanobacteria that produce polysaccharides which aggregate particles and form a living cover on top of dryland soils. They contribute to nitrogen and hydrological cycles and prevent erosion, functions crucial to desert ecosystems. The effects of biocrusts on plant community structure remain largely unexplored, however, and even less is known about their cascading effects in consumer communities. They are also delicate micro-communities that are frequently disturbed by livestock trampling and human activities. To determine how the disturbance of biocrusts alters plant and arthropod community structure in semiarid ecosystems and connect those changes to physical, chemical, ecological, and ecosystem properties of biocrusts, we set up a fully replicated crust disturbance experiment in two ecosystems (shrubland and grassland) at the Sevilleta LTER in the spring of 2013. Each spring and fall, crews sample plant, root endophyte, rhizosphere, and aboveground arthropod communities, as well as administer disturbance treatment (via trampling). The first paper from this project showed that trampling caused direct and biologically-mediated effects on soil properties. This work was in collaboration with 2016 SEV REU student Brad Thornton. More work focusing on the plant community changes are coming! Collaborators: Dr. Jennifer Rudgers and Dr. Eva Robinson at the University of New Mexico
