Capitol Reef National Park located in southeast Utah has been exposed to grazing for about 100 years. Since then, there has been heavy controversy on the impacts of cattle on the rangeland. In the 1980’s, seven grazing exclosures (33m x 33m) were established in various areas in the park to determine the impacts of grazing compared to corresponding non-grazed areas. These have not been examined in about 30 years. Additionally, in March 2018, cattle were removed from the northern portion of the park, the Hartnet Allotment. I aim to examine the differences between plant communities, soil diversity and cryptobiotic soil between the enclosed areas and open rangeland. This will be conducted by following previous protocol in percent cover, species diversity, as well as using a DNeasy soil kit to distinguish microbial and fungal communities in plots. Observing these changes will provide a long-term dataset to investigate on how grazing and climate influenced shifts in species composition and community stability and how these systems respond after release from grazing pressure (Belote, R. et al, 2009). With this information, land managers will be able to better understand this system’s response to disturbance and to better implement restoration techniques to address these changes.
Results/Conclusions
Data collection will start June 2020 for long term analysis of these plots. Initial unpublished data were taken once per year between 1984 and 1993, immediately after the exclosures were established. Initial conclusions support that grazing alters the way rangeland communities respond to climate based on species abundance and shifts in community composition. In the 10-year span, grazing appeared to change compositional stability in response to drought years, suggesting they may be less resilient to climatic variability. Grazed plots more often had greater decrease in perennial bunchgrasses with increased annual species, causing shifts in species composition. However, it was found this may not indicate a crossing of the ecological threshold as in some cases, the composition returned to within normal range. The data also suggested gathering data on soil stability and length of gaps between plants and ground cover components could provide additional information on how species composition and ecological process may change over time. Collecting this new information as well as repeat data from this long-term study will give a better understanding if these past conclusions remain supported and how systems recover after 30 years without disturbance.