Initial Responses of In-Channel Littoral Vegetation to Restored Flow in The
Kissimmee River
Stephen G. Bousquin
Kissimmee Division
South Florida Water Management District
West Palm Beach, Florida, USA
Prior to channelization, the extent and species composition of littoral plant
communities in the Kissimmee River were typical of a low-gradient lotic
environment. Aquatic vegetation was limited, likely primarily by flow, to narrow
littoral zones dominated by emergent species. With the dredging of canal C-38
and diversion of flow to the canal, remnant channels became nonflowing pools.
Littoral vegetation beds expanded in width towards mid-channel areas, and cover
of floating and mat-forming species increased relative to cover of emergent
species. Extensive vegetation beds, typically dominated by floating exotic
species, often completely spanned channels. To monitor responses of littoral
vegetation to restored flow, we collected data twice annually (winter and summer)
from 1998-2002 at 91 permanent transects in remnant channels of Pools B and C
of the Kissimmee River. Means were estimated for each of three time intervals: a
baseline period (February 1998-June 1999), an initial response period following
backfilling (August 1999-September 2000), and a post construction period
(January 2001-September 2002). Mean vegetation bed widths, mean relative
cover of floating and mat-forming plant species, and mean percentage of channel
that was vegetated all declined in each time interval.
Bousquin, Stephen G., Kissimmee Division, South Florida Water Management
District, 3301 Gun Club Road MS 4470, West Palm Beach, FL, 33416-4680,
Phone: 561-682-2719, Fax: 561-682-0100, sbousqu@sfwmd.gov