Regional forest fragmentation effects on bottomland hardwood community types and resource values

Abstract

In human-dominated regions, forest vegetation removal impacts remaining ecosystems but regional-scale biological consequences and resource value changes are not well known. Using forest resource survey data, I examined current bottomland hardwood community types and a range of fragment size classes in the south central United States. Analyses examined resource value indicators, appraised tree-based flood zone and shade tolerance indices, and identified potential regional-scale processes. Findings revealed that the largest fragments had fewer tree species, reduced anthropogenic use evidence, and more older and wetter community types than small fragments. Results also suggested the need for incorporating hydrologic, geomorphic, and understory vegetation parameters in regional forest resource monitoring efforts. Two regional-scale processes are hypothesized: (1) forest fragmentation occurs more frequently in drier habitats and dry zone (inundated ≤ 2 months annually), younger seral stage bottomland community types; and (2) forest fragmentation induces establishment of drier habitats or dry zone, younger serai stage community types. Both hypotheses suggest that regional forest fragmentation impacts survival of distinct community types, anthropogenic uses, and multiple resource values.