Community and Ecosystem Effects of Buffelgrass (Pennisetum ciliare) and Nitrogen Deposition in the Sonoran Desert
| Autor: | Kelly G. Lyons, Baruk G. Maldonado-Leal, Gigi Owen |
|---|---|
| Rok vydání: | 2013 |
| Předmět: |
0106 biological sciences
Biomass (ecology) biology Ecology 04 agricultural and veterinary sciences Plant Science Vegetation biology.organism_classification 010603 evolutionary biology 01 natural sciences Arid Invasive species Habitat 040103 agronomy & agriculture 0401 agriculture forestry and fisheries Environmental science Ecosystem Rangeland Pennisetum |
| Zdroj: | Invasive Plant Science and Management. 6:65-78 |
| ISSN: | 1939-747X 1939-7291 |
| DOI: | 10.1614/ipsm-d-11-00071.1 |
| Popis: | Buffelgrass is a non-indigenous, invasive, C4 grass that was introduced throughout much of southern Texas, the Southwestern United States, and northern and central Mexico to improve degraded rangelands. The successful introduction and spread of buffelgrass follows a trajectory similar to that of other invasive C4 grasses in arid and semiarid ecosystems. In the Plains of Sonora of the Sonoran Desert (Mexico) buffelgrass is favored by widespread removal of native vegetation and seeding, but, why, following initial introduction, the species persists remains unclear. In this study, we addressed two concerns associated with buffelgrass invasion in the Plains of Sonora. We hypothesized that under arid rangeland conditions, buffelgrass outcompetes native herbaceous species (1) through rapid acquisition of limiting nutrients (here assumed to be nitrogen) and (2) under conditions with high nitrogen input. In summer 2002, a 2 by 2 factorial experiment was established with buffelgrass removal and nitrogen addition in both intact desert and converted buffelgrass grassland habitats. In winter 2003, we found that, regardless of habitat type, buffelgrass removal had a positive effect on abundance, biomass, and richness of native herbaceous species while addition of nitrogen, as urea (at 50 kg N ha−1yr−1 or 9.18 lbs N ac−1yr−1), and disturbance resulted in reduction in abundance and biomass. Nitrogen addition did not negatively alter buffelgrass cover. Nitrogen addition had the expected result of increasing initial, peak and total NO3 and NH4 mineralization with the exception of NO3 measures in intact desert. Removal of buffelgrass did not result in significant increases in soil NO3 or NH4 with the exception of peak NH4 in intact desert. Results of this study support observations that native herbaceous species are displaced by buffelgrass invasion and that nitrogen pollution will likely favor buffelgrass over the native herbaceous species in this ecosystem. |
| Databáze: | OpenAIRE |
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