Abstract

Field methods, a normalized difference vegetation index (NDVI) and a geographic information system (GIS) were used to analyze the recovery of wetland plant communities altered by historic agricultural disturbance. Rice fields abandoned at 3, 30, 75, and 132 yr prior to fieldwork were compared to an uncultivated control site for this study. Site physical characteristics and treatments were used to postulate mechanisms that facilitate changes in wetland plant communities. Abundance and dominance data for each species were recorded. Results show that disturbed communities did not return to the referenced control community composition. Areas disturbed by past agriculture are dominated by a mixture of Zizania aquatica, Zizaniopsis miliacea, and Juncus roemerianus. Dispersal trends of woody species in disturbed areas occurred methodically from riverside embankments to the island interiors. While woody patch distributions are greatest near riverside embankments, there is also evidence of an increase in woody patch distribution dispersing into island interiors.

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