Print PageA status report and prognosis for grasslands of the Rocky Mountain region was presented over a decade ago. The term ‘novel ecosystem’ had yet to appear, but the grasslands were identified using terminology now identifying these communities that contain both native and non-native species and exhibit biogeochemical characteristics not previously found in these regions. Here, an updated evaluation of the causes and consequences of current and future changes in the relative abundance and composition of grasslands within the Rocky Mountain region is presented.
Results/Conclusions
The base camps to the Rockies, the grasslands found around and within the mountains, continue to be transformed by the directional environmental drivers of the early Anthropocene. Transformations to new states are not all in the same direction. New mountain meadows and savannas are being created by multiple disturbances, the most common of which is the combination of beetle-kill or a fire followed by a subsequent fire to the regrowth forest. These new communities are influenced by increased nitrogen deposition and often appear to favor grasses over native forbs; however, a subset of non-native forbs has done well in this milieu. Grasslands present at the time of European settlement continue to transform to less-grassland-like communities (shrublandification) due to legacies of human use, fragmentation, and fire suppression in and around areas with higher human densities. Finally, grasslandification has also continued in a subset of the region due, in part, to an expanded growing season and moisture regime that favors winter annual grasses. Fire has always been the ally of grasslands, and this ally is likely to guarantee the persistence if not the expansion of large expanses of grasslands and meadows within the Rocky Mountain region.
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