ACIDIFICATION AND FISH OCCURRENCE IN THE UPPER CHEAT RWER DRAINAGE, WEST VIRGINIA¹

Abstract

The decline of many fish populations within the mid‐Appalachian region has been attributed to stream acidification as a result of acid precipitation. Many previous attempts to examine relationships between fish occurrence and acidification have been hindered by a lack of data on water quality and fish distributions. To assess relationships between water quality and bedrock type in the upper Cheat River drainage, we used EPA STORET water quality data (1969–1993) and calculated mean pH and mean alkalinity of streams associated with four bedrock types (Hampshire, Chemung, Mauch Chunk, and Pottsville). We examined the relationship between fish occurrence and bedrock type for 53 headwater streams. We found that acidity in headwater streams associated with Pottsville and Mauch Chunk groups often exceeded biological thresholds for acid‐sensitive fish species (pH < 5.5). Streams associated with the Pottsville group typically had fewer cyprinid species and fewer total species than those associated with Mauch Chunk, Chemung, and Hampshire bedrock types. The congruent occurrence of streams with low buffering capacity, streams with pH > 5.5, and streams with low fish species richness indicate that acidification has influenced fish distributions in the upper Cheat River drainage.

The Role of Terrestrial Invertebrates in Allopatric Brook Trout Headwater Streams in the Central Appalachian Mountains

“…Watershed sizes range from 2.6 to 8.2 krn2, and are -characterized by riparian areas containing stands of mixed-deciduous hardwoods. The streams all contain the Chemung Formation as the dominant geologic type, which is characterized by sandstone and siltstone rocks and acidbuffering capabilities sufficient for brook trout (Welsh and Perry 1997). All stream channels consisted mainly of cobble and gravel.…”

Age and growth of Appalachian brook trout in relation to life-history and habitat features

“…Through natural weathering processes, bedrock releases base cations into surface waters allowing for the neutralization of acid. Waters flowing over Hampshire (limestone dominated) geologic types will release greater amounts of base cations and thus provide a stronger buffer against acidic inputs (Welsh and Perry 1997). However, as weathering properties vary among geologic types so will the buffering ability provided by each.…”

“…For instance, streams flowing over Pottsville (sandstone dominated) geologic types may be at greater risk of acidification as this geologic type offers little buffering capacity (Herlihy et al 1993). Within an area which receives high amounts of acid rain such as the mid-Appalachian region, geology may play an important role in influencing the pH of running waters and thus the aquatic organisms which are supported within these environments (Sharpe et al 1987, Welsh and Perry 1997, Eggleton and Morgan 2001.…”

“…However research such as this within Appalachia is rare. Within Appalachia, fish occurrence has been attributed to geologic type (Sharpe et al 1987, Welsh andPerry 1997). Streams flowing over poorly buffered geologic types (Pottsville) tended to contain less diverse fish populations (Welsh and Perry 1997).…”

“…Within Appalachia, fish occurrence has been attributed to geologic type (Sharpe et al 1987, Welsh andPerry 1997). Streams flowing over poorly buffered geologic types (Pottsville) tended to contain less diverse fish populations (Welsh and Perry 1997). While brook trout may be more resilient to acidic conditions compared to other species found within these systems, brook trout occurrence is also likely influenced by geology (Sharpe et al 1987).…”