Subalpine Meadow Plant Communities in Yosemite and Sequoia and Kings Canyon National Parks, 2011-2012

This publication presents data collected within meadows from samples used to assess meadow plant community responses to recreational pack stock as part of a USGS Natural Resources Preservation Project. High elevation meadows are a vital ecological component of mountain systems throughout western North America. They provide critical habitat for wildlife, supply key ecosystem services, and are favored destinations for people visiting the mountains. The biophysical characteristics of meadows are highly variable, especially related to hydrologic regimes and associated plant community types. In the semi-arid landscape of the Sierra, water availability operates at multiple scales strongly influencing meadow plant community structure. Among meadows, variability in plant communities may be due to larger-scale influences on water availability such as elevation, regional climate, or basin hydrology, whereas within-meadow variability is largely an outcome of heterogeneity in local soil moisture regimes. Complicating processes at each scale is the high inter-annual variability in moisture conditions that occur across the Sierra Nevada. Inter-annual variability in meadow moisture can have a strong influence on meadow vegetation that may outweigh local disturbance impacts. Additionally, wet versus dry meadows at the two ends of the productivity spectrum can differ greatly in hydrologic regime and plant community structure, and differences likely outweigh the more localized and potentially lesser effects of pack stock. In addition, different meadow types can display varied resilience to vegetation removal, such that some display compensatory growth and may increase in cover. These considerations suggest that if pack stock do significantly affect meadow plant communities, detecting these effects will be difficult unless the underlying variability among meadow types is controlled for. We adopted a multivariate matching technique utilizing remotely sensed hydro-climatic and geospatial data to pair stock use meadows with similar non-stock (reference) meadows to control for the natural variability inherent to meadow ecosystems.

These data support the following publication:
Lee SR, Berlow EL, Ostoja SM, Brooks ML, Gnin A, Matchett JR, et al. (2017) A multi-scale evaluation of pack stock effects on subalpine meadow plant communities in the Sierra Nevada. PLoS ONE 12(6): e0178536. https://doi.org/10.1371/journal.pone.0178536