Location: Rangeland Resources & Systems ResearchTitle: Evaluating composition and conservation value of roadside plant communities in a grassland biome Author
|Soper, Jon - University Of Nebraska|
|Wienhold, Carol - University Of Illinois|
|Schacht, Walter - University Of Nebraska|
Submitted to: Environmental Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/26/2019
Publication Date: 3/25/2019
Citation: Soper, J.M., Raynor, E.J., Wienhold, C., Schacht, W.H. 2019. Evaluating composition and conservation value of roadside plant communities in a grassland biome. Environmental Management. https://doi.org/10.1007/s00267-019-01154-x.
DOI: https://doi.org/10.1007/s00267-019-01154-x Interpretive Summary: This study contributes a better understanding of the success of roadside restoration across a gradient of precipitation (eastern to western Nebraska) and how landscape-context mediates plant community composition and resilience to invasion from non-native seed sources. This foundational work on Nebraska roadside plant community ecology establishes that Nebraska roadsides are viewed as a resource where plant communities with a diversity of native grassland species can be established; however, the persistence of many seeded, native species is minimal (mostly forbs) because of the competitiveness of both seeded and invasive species of grass.
Technical Abstract: In the context of roadside revegetation activities in rural regions, revegetation objectives commonly are to establish plant communities with a diversity of species that would otherwise be absent on the predominantly agricultural landscape. To determine the efficacy of revegetation in providing plant communities of high biodiversity value, we quantified species richness, floristic quality, and success in seeding efforts. We evaluated the outcome of roadside seedings conducted by Nebraska Department of Transportation (NDOT) for five NDOT landscape regions spanning Nebraska. Our assessment occurred on average 13.2 years (range: 10–17) post-revegetation, thus, providing insight into what established plant communities can be expected after a decade or more. Biomass production declined on an east to west gradient, but the component species responsible for this gradient were unique to each region. We found species richness was greatest in the western regions of Nebraska with the Sandhills supporting the highest richness. This rangeland-dominated region exhibited the highest floristic quality index, a tool commonly used to identify areas of high conservation value. Our findings indicate that the roadside vegetation is landscape-dependent in that neighboring plant communities influence botanical composition of roadside vegetation. Thus, less diverse seeding mixtures could be used on roadsides with a diversity of desirable native plant species in neighboring land (i.e., Sandhills rangeland). Conversely, in roadsides surrounded by cropland or plant communities with many non-native, weedy species, seeding complex mixtures with a diversity of desirable and highly competitive native species is likely necessary. Nebraska roadsides are viewed as a resource where plant communities with a diversity of native grassland species can be established; however, persistence of many seeded, native species is minimal (mostly forbs) because of the competiveness of both seeded and invasive grasses.