Semester

Fall

Date of Graduation

2009

Document Type

Thesis

Degree Type

MS

College

Davis College of Agriculture, Natural Resources and Design

Department

Wildlife and Fisheries Resources

Committee Chair

J. Todd Petty.

Abstract

West Virginia is one of the leading producers of coal in the United States. Large scale surface mining (mountaintop removal mining, MTR) has become commonplace in WV as a technique for accessing thin layers of coal that may be difficult or impossible to access through traditional underground mining techniques. MTR disturbs large areas of land and often results in a complete rearrangement of headwater catchments. Although restoring original pre-mining conditions is ideal, it is usually unrealistic in this region. Consequently, the extent to which post-reclamation watersheds function relative to the pre-mining conditions is unclear. The objectives of this study were to (1) quantify the functional value of reference headwater streams and post-reclamation aquatic features, (2) determine whether ecological functions are adequately replaced after mining and reclamation, and (3) develop recommendations for mining reclamation and direction for future studies.;Typically during mining and reclamation, steep, forested, ephemeral and intermittent stream channels that existed pre-mining are replaced with unforested, gently rolling terrain. Intermittent and perennial aquatic channels develop along the mine perimeter. These channels are constructed as sediment control complexes during the mining and mine-reclamation process. These aquatic features remain on the landscape post-reclamation and were the focus of this study's functional evaluation. Elevated metal concentrations were observed during some seasons at some mined locations. Overall, however, the reclamation process appears to do a good job of controlling metal contamination in water runoff. Perimeter channels, however, produced significantly higher levels of alkalinity, calcium, iron, magnesium, sulfate, specific conductivity, and total dissolved solids (TDS). Previous studies have shown these parameters to have significant downstream impacts on aquatic communities. These parameters are difficult to treat on-site and may be best managed at a watershed scale through the protection of undisturbed headwater catchments.;Over time, the reclaimed perimeter channels become vegetated with obligate wetland species, creating a considerable difference between mined and reference channels with regard to vegetation assemblages, canopy cover, and aquatic habitat quality. Species richness of macroinvertebrates and amphibians remains comparable between mined and reference channels. However, there is a distinct shift from sensitive, lotic taxa to tolerant, lentic taxa.;Reclaimed perimeter channel sites have a reduced ability to breakdown organic matter (OM), most likely as a result of reduced mechanical abrasion and reduced microbial activity due to elevated conductivity. Nevertheless, mined channels have significantly higher OM retention than reference channels. Consequently, perimeter channels show significantly higher overall processing power than reference channels. In other words, OM that enters a perimeter channel is retained and processed locally at a higher rate, whereas a greater proportion of OM entering a reference channel is transported downstream before being processed. As a result of higher OM retention and processing power, perimeter channels exported significantly more winter dissolved organic carbon (DOC) than reference stream sites.;This study represents a snapshot of relatively young (3 to 20 year old) reclaimed sites. Changes in vegetation, from open grassland to closed canopy forests, are expected as plant succession occurs over time. In addition, leaching of soluble salts may moderate many of the noted parameters such as alkalinity and sulfate that constitute high TDS values. Still, little is known about the rates and controlling factors of temporal changes.;Overall, a combination of on-site reclamation, off-site mitigation for lost structural components, and compensation at a watershed scale may be the best solution for shortcomings in current permitting and reclamation processes. Protecting native stream channels within mining-impacted watersheds would serve both as a source of dilute fresh water to compensate for alkaline drainage parameters and as a safeguard against the regional extinction of sensitive taxa.;Key words: decomposition, dissolved organic carbon, mitigation, ecological units, coal mining, amphibian colonization, macroinvertebrate colonization, surface mine reclamation, wetland creation, elevated conductivity and total dissolved solids.

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