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The Healy quadrangle Is underlain by a wide variety of sedimentary, volcanic, and plutonic rocks, ranging In age from Precambrlan and (or) early Paleozoic to Recent. There are fifty five map units on the geologic map. All the pre-Cenozolc rocks are Intensely deformed, mainly by overthrusting and folding, and most of them underwent at least one period of low-to medium-grade regional metamorphlsm. This deformation 1s the result of the middle Cretaceous collision and subsequent obductlon of the northward-moving Talkeetna superterrane with and onto the Yukon-Tanana and Nixon Fork terranes of the ancient North American continent. Late Cenozoic deformation, the result of continued northward plate motions, has modified but not substantially altered the geology of the quadrangle.

Activities such as agriculture, silviculture, and mining contribute nonpoint pollution to Alabama's streams through polluted runoff and excessive sedimentation. Highly erodible soils characteristic of the Choctawhatchee‐Pea Rivers watershed, combined with intense rainfall and land use practices, contribute large amounts of sediment to streams. Biological monitoring can reflect the acute impacts of pollutants as well as prolonged effects of habitat alteration, and development of biological criteria is important for the establishment of enforceable laws regarding nonpoint source pollution. Macroinvertebrates were collected from 49 randomly selected sites from first through sixth‐order streams in the Choctawhatchee‐Pea Rivers watershed and were identified to genus level. Thirty‐eight candidate metrics were examined, and an invertebrate community index (ICI) was calibrated by eliminating metrics that failed to separate impaired from unimpaired streams. Each site was scored with those metrics, and narrative scores were assigned based on ICI scores. Least impacted sites scored significantly lower than sites impacted by row crop agriculture, cattle, and urban land uses. Conditions in the watershed suggest that the entire area has experienced degradation through past and current land use practices. An initial validation of the index was performed and is described. Additional evaluations of the index are in progress.

Forces driving the initiation of watershed management activities in Alabama have ranged from top‐down, agency‐led initiatives to bottom‐up, citizen‐led initiatives. A number of watershed projects in Alabama were examined including three NPS projects funded by U.S. EPA grants and a more comprehensive locally‐initiated watershed management authority. Watershed projects were categorized into four different models. Factors which produced significant differences in the development and utilization of social capital and local capacities for watershed management were investigated. The success of watershed management initiatives was examined qualitatively and appears to correlate with a number of social factors. These factors include the extent of stakeholder involvement, the availability of social capital in the watershed, and the presence of a real or perceived water resource concern or problem. Both short term project success and the longer term prognosis for continued watershed management activities seems to depend most upon the amount of social capital in the watershed. Two major changes in resource management programs and organizations could lead to increased focus on and support for local watershed management initiatives. These are reorganization of resource management agencies around watershed units, and assignment of at least one staff person in each watershed unit to watershed management.

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INTRODUCTION ACKNOWLEDGMENTS

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Large wood has important structural and functional roles in streams but there is little information on large wood dynamics in the southeastern coastal plains, USA. In this study, we surveyed 35 streams in the Choctawhatchee River watershed of southeastern Alabama. These streams were broadly classified into three categories based on land use: urban, forest, and mixed (agriculture plus forest). The number, volume, and functions of large wood were quantified. Pool number, pool spacing, and drainage areas of each stream were measured along with assessment of macroinvertebrate assemblages. Large wood number and volume plus pool number and spacing were used to examine the relationship among large wood characteristics and functions, pool characteristics, drainage area, and attributes of macroinvertebrate assemblages including species richness, Shannon-Wiener diversity (H 0 ), number of Ephemeroptera, Plecoptera, and Trichoptera (EPT) species, and the Invertebrate Community Index (ICI -a multimetric index that reflects biological integrity of streams). There were significant differences in large wood number and volume among the three different stream categories, with highest large wood number and volume in forest streams. More pools and storage sites for sediment and organic matter were found in forest streams than urban and mixed streams. Large wood appeared to be positively related to macroinvertebrate assemblages, as species richness, H 0 , EPT, and ICI were generally higher in forest streams as compared to those of urban and mixed streams. The outcome of this study suggests that large wood contributes to the physical and biological complexity of streams in the southeastern coastal plain streams of the USA.