Dryland bryophyte ecology and restoration

Bryophytes in Drylands

Undisturbed interspaces between native shrubs, perennial grasses and forbs in drylands are often covered in biological soil crusts (biocrusts). Biocrusts are complex associations of lichen, cyanobacteria, and moss that differ greatly in community composition along an aridity gradient. Cyanobacteria or lichen dominate biocrust communities in drier locations while bryophytes are more prevalent in less arid environments like northern intermountain grasslands. Biocrusts are well recognized for their ecological importance in arid and semi-arid systems worldwide.

Disturbance and vascular plant establishment

Lichen and cyanobacteria dominated biocrusts have been found to generally inhibit seedling establishment. To get around this, many native species have developed specialized seeds that can drill through the biocrust layer. In some cases, non-native species are kept of the ecosystem this way until disturbance opens up direct soil access. Much less is known about how mixed bryophyte and lichen biocrust communities regulate native and non-native plant establishment and how their disturbance and changing precipitation patterns might influence these outcomes. This work is being done in collaboration with Dean Pearson (UM/USFS) and Nichole Barger (CU Boulder/TNC).

Restoration of bryophyte-dominated biocrusts

In areas where disturbance has facilitated the invasion of non-native species, land managers often focus on restoring native species like bunchgrasses but do not consider the importance of restoring biocrusts. Restoration of biocrust communities is a fundamental component of reestablishing the natural community composition and ecosystem function in dryland systems. We installed long-term restoration plots in 2013 and have been monitoring moss and lichen growth and changes in nutrient availability. This work is being done in collaboration with Rebecca Durham at MPG Ranch.