SUMMARY AND CONCLUSIONS 



Bottomland hardwood forests are dynamic and complex systems. 

 Frequent flooding from adjacent streams provides the forcing function 

 that characterizes the affected plant communities. Frequency and dura- 

 tion of floodwater determine the extent of anaerobic soil conditions 

 that directly affect plant populations. Plant species adapted for life 

 in anerobic soil conditions are located in the topographically lowest 

 areas subject to long duration flooding. Species composition changes as 

 the elevational and associated moisture gradient changes from wettest to 

 driest, and reflects species adaptations to the prevailing hydrologic 

 regimes . 



Determination of a hydrologic gradient often requires extensive 

 data gathering over a long period. However, many studies have shown 

 that a definite relationship exists between plant species and the tim- 

 ing, frequency, and duration of inundation and soil saturation (Larson 

 et al . 1981). This study was undertaken to express quantitatively the 

 optimum position of various plant species along a hydrologic gradient. 



Previous studies have estimated the location of plant species and 

 communities along a hydrologic gradient. Various systems have been 

 proposed that use vegetation to predict the duration and/or frequency of 

 flooding. However, previous studies were limited to a small geographic 

 area, the developed systems are qualitative, and vegetation data used to 



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