95th ESA Annual Meeting (August 1 -- 6, 2010)

PS 46-167 - The effects of seasonal mowing on bryophytes in a tallgrass prairie ecosystem

Tuesday, August 3, 2010
Exhibit Hall A, David L Lawrence Convention Center
Channing Richardson and Michael W. Palmer, Botany, Oklahoma State University, Stillwater, OK
Background/Question/Methods

Though the effects of mowing on bryophyte communities have not been well documented, there are several examples in the literature that show that nonvascular plants respond to other types of disturbances. In this study we sought to quantify the characteristics of bryophyte communities in relation to various long-term mowing treatments.  This study expands upon a long-term study of mowing effects on a tallgrass prairie ecosystem, in which 144 permanent 1x1meter plots were established inside of 2x2m treatment areas (in order to avoid edge effects). Mowing treatments were assigned using a randomized-block design. Treatments consisted of all combinations of March, June, and September mowing as well as control plots that have not been mown for the past 12 years.  These plots are located in western Payne County, Oklahoma.  Within each 1x1m plot, we identified terricolous bryophyte species and recorded percent cover.  We conducted this field work in January and February of 2010.

Results/Conclusions

The most abundant species we recorded was Weissia controversa which occurred in 107 (74%) of the plots. Weissia muhlenbergiana was the second most abundant species occurring in 87 (60%) of the plots.  The highest number of taxa recorded for any plot was 8.  The lowest number recorded was 0.  The highest cover for any individual bryophyte species was Ctenidium molluscum at 4%.  Mowing resulted in higher species diversity and cover than was seen in the control plots.  Differences between the various mowing treatments were more subtle.