Abstract. Livestock overgrazing and stream incision in the western USA often result in encroachment and dominance of Artemisia tridentata ssp. tridentata (Big sagebrush) in riparian areas that formerly supported meadows. To define the alternative states and thresholds for these ecosystems, we conducted a restoration experiment that included sites with high, intermediate or low water tables. We used a paired‐plot approach in which one plot on each site was burned and seeded with native grasses and forbs typical of naturally occurring dry meadow and Artemisia/Leymus cinereus ecological types, while adjacent unburned plots served as controls. Sites with high and intermediate water tables had greater initial abundances of perennial grasses typical of dry meadows, such as Leymus triticoides and Poa secunda ssp. juncifolia, and these species increased after the burn. In contrast, sites with low water tables were dominated by annual forbs such as Chenopo‐dium album and Descurainia pinnata after the burn. Biomass increased progressively from 1997 to 1999 on burned plots, while controls showed little change. Burning effects were microsite specific, with former Artemisia microsites exhibiting lower biomass than interspaces initially, but similar or higher biomass by the third year. Establishment of seeded species was low and species composition was determined largely by pre‐burn vegetation. Artemisia dominated sites with high water tables appear to represent an alternative state of the dry meadow ecological type, while sites with low water table sites have crossed an abiotic threshold governed by water tables and represent a new ecological type. Burning is an effective tool for restoring relatively high water table sites, but low water table sites will require burning and seeding with species adapted to more xeric conditions.
Using a pretest-posttest quasi-experimental control group design, a learning environment study was conducted to evaluate the environmental literacy of postsecondary, nonscience majors. Data were collected from 183 students taking an introductory environmental science class—a 41-question Environmental Literacy Instrument (ELI) prompted students for responses across four subscales of environmental literacy: Knowledge, Beliefs, Opinions, and Self-Perceptions. Differences between presurvey and postsurvey scores were compared to determine whether a constructivist-based or traditional learning environment improved students' environmental literacy more. Results showed that the constructivist-based curriculum was not a significant factor of influence, suggesting that regardless of which learning environment they were exposed to, participants experienced similar improvements to their environmental literacy across a 16-week semester. Given that the findings were contrary to expectations, and counterindicated by several other learning environment studies as well, a broader investigation as to why the two learning environments produced similar results is warranted.
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