Soil Seed Banks and Germination Traits in Northern Arizona Grasslands
Purpose: We are examining soil seed banks inside and outside grazing exclosures in House Rock Valley, Arizona to understand drivers of vegetation community change and persistence following a legacy of domestic livestock grazing. Soil seed bank analyses can indicate the potential for spontaneous recovery of vegetation communities, as well as the degree or type of restoration required to return the ecosystem to a desired state following the cessation of disturbance. Additionally, we are investigating relationships between seed traits and germination for a suite of native grassland/steppe species (list below) to inform restoration seeding practices. Seed traits are a key factor in species’ dispersal, establishment, and persistence in communities; they interface with environmental filters at several critical life history stages including dispersal, seed bank residency, germination, and seedling establishment. In light of increased drought frequency and duration due to climate change, insights about soil seed banks and regeneration traits in relation to legacy and current land use practices will help identify mechanisms by which different species may respond to varying environmental conditions or restoration practices in arid northern Arizona grasslands.
Species list for seed trait and germination analysis:
Perennial Grasses: Achnatherum hymenoides, Sporobolus cryptandrus, Hesperostipa comata
Annual Forbs: Peritoma lutea, Phacelia crenulata, Stephanomeria exigua, Streptanthus longirostris
Shrub: Atriplex canescens
Society for Ecological Restoration at NAU (SER NAU), Native Wildflowers for SNAIL Garden and Plant Sales
SER NAU is a student-led organization focused on providing opportunities for students to learn about and proactive ecological restoration on campus and in the broader community. We are currently growing native wildflowers (Penstemon palmeri, Rudbeckia hirta, and Ipomopsis aggregata to plant in the SNAIL Garden and sell at fundraising events.
Ashlee Simpson, Master’s student NAU
Rachel Mitchel, Assistant Professor Earth and Sustainability