Stream/River Channel Characteristics

Monitoring Objectives

• Determine trends in the quantity and distribution of macrohabitat features such as channel dimensions (longitudinal profile and cross-sections), percent cover of habitat units (runs, riffles, and pools), and channel hydraulic relationships
• Determine trends in the quantity and distribution of microhabitat features such as detritus, coarse woody debris, and bed sediments

Background
Alteration to the hydrological regime is a common disturbance in a variety of southeastern ecosystems: bottomland and floodplain forests, mountain bogs, rocky stream gorges, longleaf pine savanna, Carolina bays, pocosins, Atlantic white-cedar swamps, barrier-island communities, mangrove forests, rivers, streams, caves, lakes, and the Everglades mosaic of communities. Hydrological change has altered flood depth, duration, frequency, and seasonal timing in many of these systems, leading to a raising and lowering of the water table in specific cases.

Stream habitat units are composed of channel and bar features that are sensitive to changes in environmental factors and disturbance within the watershed. Habitat and other geomorphic variables measured from topographic surveys can be evaluated with geomorphic and hydraulic equations and/or indexes to determine the status of aquatic habits. In addition, trend analysis of quantifiable geomorphic variables representing the quantity and structure of in-stream habitats is a useful tool for monitoring the influence of natural and human drivers on habitat quality. Key measures include channel slope, riffle and pool spacing and area, bankfull channel width and depth, and flow velocity. The methodology for geomorphic assessments of streams is standard in the field and its application to habitat inventories well established.

Monitoring Approach
Several stream habitat protocols exist and will be tested for their applicability to SECN streams. A combination of transect- and reach-based approaches will be used to monitor stream habitat (such as Gorman and Karr 1978, Platts et al. 1983, Simonson et al. 1993, Illinois Environmental Protection Agency 1994, Simonson et al. 1994, Fitzpatrick et al. 1998). After Network protocols are selected, stream habitat data will be collected in conjunction with stream water quality monitoring. The sampling plan will follow a generalized random tessellation stratified design which randomly selects sites with guaranteed spatial balance, ensuring park-wide inferences can be made (McDonald and St.Clair 2004). Sites will be co-located with sampling sites with other protocols, particularly water chemistry.

For parks where multiple sampling locations exist, the spatial unit to be evaluated will be a reach composed of three sequential riffle-pool units with an overall length of approximately four riffles from crest to crest. In some cases, sampling will be limited to sites at the upstream and downstream extent of Park boundaries. Protocol alternatives will be provided for SECN streams as well as for three reach scales: (1) small wadeable streams that are <10 meters wide); (2) large wadeable streams that are10-50 meters wide); and (3) nonwadeable streams (width measures are approximate).

Parks Where Protocol Will be Implemented
Horseshoe Bend National Military Park (HOBE), Kennesaw Mountain National Battlefield Park (KEMO), Chattahoochee River National Recreation Area (CHAT), Ocmulgee National Monument (OCMU), Congaree National Park (CONG) and Moores Creek National Battlefield (MOCR

Principal Investigator
SECN Aquatic Ecologist / Water Quality Specialist (position currently vacant)