Bottomland hardwood forests are highly productive ecosystems which perform many important ecological services. Unfortunately, many bottomland hardwood forests have been degraded or lost. Accurate land cover mapping is crucial for management decisions affecting these disappearing systems. SPOT-5 imagery from 2005 was combined with Light Detection and Ranging (LiDAR) data from 2006 and several ancillary datasets to map a portion of the bottomland hardwood system found in the Sulphur River Basin of Northeast Texas. Pixel-based classification techniques, rulebased classification techniques, and object-based classification techniques were used to distinguish nine land cover types in the area. The rule-based classification (84.41% overall accuracy) outperformed the other classification methods because it more effectively incorporated the LiDAR and ancillary datasets when needed. This output was compared to previous classifications from 1974, 1984, 1991, and 1997 to determine abundance trends in the area’s bottomland hardwood forests. The classifications from 1974-1991 were conducted using identical class definitions and input imagery (Landsat MSS 60m), and the direct comparison demonstrates an overall declining trend in bottomland hardwood abundance. The trend levels off in 1997 when medium resolution imagery was first utilized (Landsat TM 30m) and the 2005 classification also shows an increase in bottomland hardwood from 1997 to 2005, when SPOT-5 10m imagery was used. However, when the classifications are re-sampled to the same resolution (60m), the percent area of bottomland hardwood consistently decreases from 1974-2005. Additional investigation of object-oriented classification proved useful. A major shortcoming of object-based classification is limited justification regarding the selection of segmentation parameters. Often, segmentation parameters are arbitrarily defined using general guidelines or are determined through a large number of parameter combinations. This research justifies the selection of segmentation parameters through a process that utilizes landscape metrics and statistical techniques to determine ideal segmentation parameters. The classification resulting from these parameters outperforms the classification resulting from arbitrary parameters by approximately three to six percent in terms of overall accuracy, demonstrating that landscape metrics can be successfully linked to segmentation parameters in order to create image objects that more closely resemble real-world objects and result in a more accurate final classification.

Catastrophic wind events can play an important role in the stand structure and composition in Bottomland Hardwood Forests. Regeneration and stand structure following these events depends on a variety of factors, including disturbance severity, past land use, and post-disturbance management. This study revisits a 2004 survey conducted at Mermet Lake State Fish and Wildlife Area in Southern Illinois following a tornado and subsequent salvage logging operation. We established 164 plots on four different disturbance types as mapped by the original survey: Undisturbed, Transition, Wind Damaged Only, and Wind Damaged Salvaged. The objective of this study was to see how recovery differed among these. Data collected included density, basal area, and Shannon’s H, as well as visual evidence of remaining soil rutting resulting from the salvage logging operation, tree height as a metric for productivity, and invasive percent cover. There were slight but significant differences in the densities, basal area, and diversity among disturbance types, although diameter distributions revealed similar age distributions and there was no impact of the salvage logging on productivity. Evidence of soil rutting was still present, adding to microsite diversity that contributed to the significantly higher species diversity of Wind Damaged Salvaged areas. The proportion of Quercus spp. in both Wind Damaged Only and Wind Damaged Salvaged areas was lower than in Undisturbed and Transition areas, while the proportion of other species, including Fraxinus pennsylvanica and key bottomland taxa Salix spp., Taxodium distichum, and Nyssa aquatica, were higher. Invasive non-native species cover was higher in Wind Damaged Salvaged and Wind Damaged Only areas than in Transition and Undisturbed but was confined to forest edges and did not differ between Wind Damaged Salvaged and Wind Damaged Only areas. The results indicate that twenty years after the disturbance, forest structure is still recovering in tornado-damaged areas and has shifted in composition away from Quercus toward domination by Acer spp., Ulmus spp., Fraxinus pennsylvanica, and Liquidambar styraciflua species in both Wind Damaged Only and Wind Damaged Salvaged areas. The salvage logging operation did not have any negative impacts on forest recovery and supported biodiversity by further diversifying overstory community composition to include key wetland species that support the conservation area’s bottomland restoration efforts. Active management should be considered in both Wind Damaged Only and Wind Damaged Salvaged areas to prevent the spread of non-native species and ensure the persistence of Quercus and other key bottomland species in support of conservation objectives.