# Presentation: 232723

## Lower Suwannee River Floodplain, Florida: Canopy, Subcanopy, and Ground Cover Vegetation and Potential Impacts of Flow Reductions on Plant Distribution

**Melanie Darst, U.S. Geological Survey**

## AERIAL SIGNATURES IN NON-TIDAL REACH

- BOTTOMLAND HARDWOODS (blh)

## AERIAL SIGNATURES IN UPPER TIDAL REACHES

- SW

- BLH

## Tree Distribution by River Mile

- 0

- 10

- 20

- 30

- 40

- 50

- 60

- 70

**River mile**

**Lower Tidal**

**Upper Tidal**

**Riverine**

**Swamp tupelo in BLH**

**Planertree**

**Popash**

**River birch**

**Water tupelo**

**Sweetgum**

**Live oak**

**American elm**

**Swamp laurel oak**

**Red maple**

**Baldcypress**

**Swamp tupelo in swamp**

**Pumpkin ash**

**Cabbage palm**

**Sweetbay**

## FOREST TYPES:

**(LT)**

**(UT)**

**(R)**

- SEPARATED BY REACHES WITH SIGNIFICANT HYDROLOGIC DIFFERENCES

- WERE MAPPED USING INFRARED AERIAL PHOTOS (DOQs)

## 	Defined 13 wetland forest types

**	****Defined 13 wetland forest types**

- 	Measured & identified 8,756 trees
- 	77 tree species in wetland forests
- 	Bald cypress most important wetland species by basal area

## Riverine

- 3 blh types – Rblh3, Rblh2, Rblh1

**Riverine**

## 2 swamp types – Rsw2, Rsw1

## 1 bottomland hardwood type (UTblh)

1 mixed type (UTmix)

- 1 bottomland hardwood type (UTblh)
- 1 mixed type (UTmix)

## 2 swamp types – UTsw2, UTsw1

## Tree Distribution by River Mile

- 0

- 10

- 20

- 30

- 40

- 50

- 60

- 70

**River mile**

**Lower Tidal**

**Upper Tidal**

**Riverine**

**Swamp tupelo in BLH**

**Planertree**

**Popash**

**River birch**

**Water tupelo**

**Sweetgum**

**Live oak**

**American elm**

**Swamp laurel oak**

**Red maple**

**Baldcypress**

**Swamp tupelo in swamp**

**Pumpkin ash**

**Cabbage palm**

**Sweetbay**

## N

***N***

**Lower**
**Tidal**

**1  hammock type - LTham**

## N

***N***

**Lower**
**Tidal**

- 1 mixed swamp type - LTmix

## N

***N***

**Lower**
**Tidal**

- 2 swamp types – LTsw2, LTsw1

## Ground-Cover Vegetation in Wetland Forests of the Lower Suwannee River Floodplain, Florida, and Potential Impacts of Flow Reductions

- By Melanie Darst,
- Helen Light, and Lori Lewis,
- USGS

## Ground Cover Species Distribution by River Mile (282 species)

- 0

- 10

- 20

- 30

- 40

- 50

- 60

- 70

**River mile**

**Lower Tidal**

**Upper Tidal**

**Riverine**

**104 species (30 in LT and R only)**

**18 species**

**81 species**

**22 species**

**2 species**

**55 species**

## Lizard’s tail (Saururus cernuus) strongly dominates ground-cover vegetation in LTmix

## DECREASE IN DURATIONS OF INUNDATION AND SATURATION

- Some free-floating aquatic species such as humped bladderwort* * occurred only in semi-

- permanent ponds in riverine forests. They might decrease in abundance or disappear if flows were reduced.

## DECREASE IN DEPTH AND DURATION OF RIVER FLOODING

**These species occurred in Rblh, but not in Rsw, presumably because flood depth is shallower and duration of flooding is shorter. These species might become established in Rsw if flows were reduced.**

**supple jack**
**partridge berry**
**whitesands spiderlily**
**bluestem palm**

## INCREASE IN SALINITY

**Some species occurred in UTsw, but not in LTsw and are presumed to have no salinity tolerance. They might decrease in abundance in the most downstream part of the UT reach if flows were reduced.**

**eastern blue stars**
**cypress swamp sedge**
**creeping burrhead**
**narrow plumegrass**

- LTsw

## Location and Description of Ecological Study Sites in Floodplain Forests of the Lower Suwannee River, Florida

- By Lori Lewis,
- Helen Light, and Melanie Darst

## Forest Map CD

-   Interactive map using ArcExplorer software

## REPORT:

- REVIEWS FLOODPLAIN CHARACTERISTICS

- DESCRIBES  FOREST AND OTHER LAND COVER TYPES

- DESCRIBES METHODS USED TO CREATE MAP

## DISPLAY FROM INTERACTIVE MAP OF LOWER SUWANNEE RIVER FLOODPLAIN

## Available on the web at HTTP://fl.water.usgs.gov