J. Todd Petty

Spatial and Seasonal Dynamics of Brook Trout Populations Inhabiting a Central Appalachian Watershed

Abstract We quantified the watershed-scale spatial population dynamics of brook trout Salvelinus fontinalis in the Second Fork, a third-order tributary of Shavers Fork in eastern West Virginia. We used visual surveys, electrofishing, and mark–recapture techniques to quantify brook trout spawning intensity, population density, size structure, and demographic rates (apparent survival and immigration) throughout the watershed. Our analyses produced the following results. Spawning by brook trout was concentrated in streams with small basin areas (i.e., segments draining less than 3 km2), relatively high alkalinity (>10 mg CaCO3/L), and high amounts of instream cover. The spatial distribution of juvenile and small-adult brook trout within the watershed was relatively stable and was significantly correlated with spawning intensity. However, no such relationship was observed for large adults, which exhibited highly variable distribution patterns related to seasonally important habitat features, including instrea...

Additive effects of mining and residential development on stream conditions in a central Appalachian watershed

Abstract Large-scale surface mining in southern West Virginia significantly alters headwater stream networks. The extent to which mining interacts with other stressors to determine physical, chemical, and biological conditions in aquatic systems downstream is unclear. We conducted a watershed-scale assessment of Pigeon Creek, an intensively mined watershed of the Tug Fork drainage in Mingo County, West Virginia. Our objectives were to: 1) develop landscape-based indicators of mining and residential development, 2) quantify the interactive effects of mining and residential development on in-stream conditions, and 3) identify landscape-based thresholds above which biological impairment occurs in this watershed. Macroinvertebrate community structure was negatively correlated with intensity of mining and residential development. Correlation analysis and partial Mantel tests indicated that mining (% of total subwatershed area) caused acute changes in water chemistry (r = 0.55–0.91), whereas residential development (parcel density) strongly affected both physical habitat (r = 0.59–0.81) and macroinvertebrate community structure (r = 0.59–0.93). The combined effects of mining and development on in-stream biotic conditions were additive. Sites affected by equivalent levels of both stressors had lower Ephemeroptera, Plecoptera, Trichoptera richness than sites affected by either stressor alone. Biological impairment thresholds occurred at ~25% total mining (equivalent to a specific conductance of ~250 µS/cm) and at parcel densities of ~5 and 14 parcels/km2. Our results provide a tool that can be used to predict downstream ecological response to proposed mining given pre-existing watershed conditions. Our study suggests that effective management of impacts from new mine development must address nonmining-related impacts in this region.

STREAM ECOSYSTEM RESPONSE TO LIMESTONE TREATMENT IN ACID IMPACTED WATERSHEDS OF THE ALLEGHENY PLATEAU

Restoration programs are expanding worldwide, but assessments of restoration effectiveness are rare. The objectives of our study were to assess current acid-precipitation remediation programs in streams of the Allegheny Plateau ecoregion of West Virginia (USA), identify specific attributes that could and could not be fully restored, and quantify temporal trends in ecosystem recovery. We sampled water chemistry, physical habitat, periphyton biomass, and benthic macroinvertebrate and fish community structure in three stream types: acidic (four streams), naturally circumneutral (eight streams), and acidic streams treated with limestone sand (eight streams). We observed no temporal trends in ecosystem recovery in treated streams despite sampling streams that ranged from 2 to 20 years since initial treatment. Our results indicated that the application of limestone sand to acidic streams was effective in fully recovering some characteristics, such as pH, alkalinity, Ca2+, Ca:H ratios, trout biomass and density, and trout reproductive success. However, recovery of many other characteristics was strongly dependent upon spatial proximity to treatment, and still others were never fully recovered. For example, limestone treatment did not restore dissolved aluminum concentrations, macroinvertebrate taxon richness, and total fish biomass to circumneutral reference conditions. Full recovery may not be occurring because treated streams continue to drain acidic watersheds and remain isolated in a network of acidic streams. We propose a revised stream restoration plan for the Allegheny Plateau that includes restoring stream ecosystems as connected networks rather than isolated reaches and recognizes that full recovery of acidified watersheds may not be possible.

Landscape indicators and thresholds of stream ecological impairment in an intensively mined Appalachian watershed

Abstract Coal-mine development is occurring at a rapid rate in the central Appalachians, but few tools exist to assess the consequences of cumulative effects of mining to downstream aquatic resources. We constructed and applied an index of mining intensity (MI) to the Lower Cheat River basin, northern West Virginia. Our objectives were to: 1) determine if the MI could be used to predict stream-water quality and biological conditions, 2) quantify the extent to which geology and the geographic position of mines modulate the effects of mining on in-stream conditions, and 3) identify thresholds of MI that produce quantifiable changes to benthic macroinvertebrate communities. We quantified water chemistry, habitat quality, and benthic macroinvertebrate communities from May 2002 to May 2003 in 39 stream segments randomly distributed across a range of MI, coal geology, elevation, and watershed area. We sampled benthic macroinvertebrates at an additional 41 validation sites in May 2002. The MI was positively correlated with dissolved metals (r  =  0.65–0.85) and negatively correlated with ecological condition metrics (r  =  0.49–0.78), including total richness, Ephemeroptera, Plecoptera, Trichoptera richness, and the West Virginia Stream Condition Index. Coal geology and distance from mining had a significant interactive effect on benthic macroinvertebrate responses. Streams draining watersheds with Freeport coal geology had significantly poorer water quality and ecological condition than streams draining watersheds with similar MI but with Kittanning coal geology. Mining effects on stream conditions diminished as distance from the nearest mining activities upstream increased to a distance of ∼10 km. Changepoint analysis provided evidence of threshold effects of mining on benthic macroinvertebrate communities in Freeport coal watersheds but not in Kittanning coal watersheds. Abrupt reductions in ecological condition occurred at MI values as low as 1 to 5% of maximum intensity, and ecological impairment to streams became almost certain at MI >18 to 20%. Our results provide evidence of an interactive effect of landuse intensity, underlying geology, and the spatial arrangement of disturbance on the degree of impairment to receiving water bodies. The thresholds we identified could be used by water-resource managers to protect and restore stream conditions in actively mined watersheds of the central Appalachian region.

Electrofishing Capture Efficiencies for Common Stream Fish Species to Support Watershed-Scale Studies in the Central Appalachians

Abstract As watershed-scale studies of stream fishes become increasingly common, there is a need for more accurate estimation of fish population abundance and size structure with single-pass electrofishing techniques. Capture efficiencies are known to vary considerably across habitats and species, yet few studies have quantified or provided a logical framework for accounting for this variability. Consequently, our objectives were to (1) determine which species and which size-classes within species exhibited significant site-to-site variation in electrofishing efficiency and (2) construct models to predict species- and size-specific capture probability from physicochemical parameters. We used three-pass removal sampling to capture fishes from 40 study sites located in wadeable streams in the Cheat River and Tygart Valley River watersheds of West Virginia. The program MARK was used to estimate capture probabilities for 12 commonly sampled fishes, to assess among-site variability in capture probability, and ...

Water chemistry‐based classification of streams and implications for restoring mined Appalachian watersheds

We analyzed seasonal water samples from the Cheat and Tygart Valley river basins, West Virginia, USA, in an attempt to classify streams based on water chemistry in this coal-mining region. We also examined temporal variability among water samples. Principal component analysis identified two important dimensions of variation in water chemistry. This variation was determined largely by mining-related factors (elevated metals, sulfates, and conductivity) and an alkalinity-hardness gradient. Cluster analysis grouped water samples into six types that we described as reference, soft, hard, transitional, moderate acid mine drainage, and severe acid mine drainage. These types were statistically distinguishable in multidimensional space. Classification tree analysis confirmed that chemical constituents related to acid mine drainage and acid rain distinguished these six groups. Hard, soft, and severe acid mine drainage type streams were temporally constant compared to streams identified as reference, transitional, and moderate acid mine drainage type, which had a greater tendency to shift to a different water type between seasons. Our research is the first to establish a statistically supported stream classification system in mined watersheds. The results suggest that human-related stressors superimposed on geology are responsible for producing distinct water quality types in this region as opposed to more continuous variation in chemistry that would be expected in an unimpacted setting. These findings provide a basis for simplifying stream monitoring efforts, developing generalized remediation strategies, and identifying specific remediation priorities in mined Appalachian watersheds.

Watershed analysis with GIS: The watershed characterization and modeling system software application

The watershed characterization and modeling system (WCMS) was developed to support decision making and the management of water resources at a statewide level in West Virginia. Specific hydrological analysis functions were combined within a customized GIS interface to provide decision support capabilities to both technical and non-technical users. Components of the current system include: an overland flow path model that indicates optimum water quality sampling locations, flow estimation for all streams in an identified area, an instream water quality and loading model for pollutant levels, and a ranking model to prioritize treatment alternatives based on user defined criteria and preferences. The primary goals of this system are to provide consistent technical information related to natural watershed processes and to predict the impacts of alternative management scenarios for decision makers. WCMS is currently used by the West Virginia Department of Environmental Protection (WVDEP) to guide policy development and management decisions that address watershed and water quality issues throughout the state.

Hierarchical classification of stream condition: a house–neighborhood framework for establishing conservation priorities in complex riverscapes

Abstract.  Despite improved understanding of how aquatic organisms are influenced by environmental conditions at multiple scales, we lack a coherent multiscale approach for establishing stream conservation priorities in active coal-mining regions. We classified watershed conditions at 3 hierarchical spatial scales, following a house–neighborhood–community approach, where houses (stream segments) are embedded within neighborhoods (Hydrologic Unit Code [HUC]-12 watersheds) embedded within communities (HUC-10 watersheds). We used this information to develop a framework to prioritize restoration and protection in two HUC-8 watersheds in an intensively mined region of the central Appalachians. We used landscape data to predict current conditions (water chemistry and macroinvertebrate biotic integrity) for all stream segments with boosted regression tree (BRT) analysis. Mining intensity, distance to mining, and coal type were the dominant predictors of water quality and biological integrity. A hardness–salinity dimension of the water-chemistry data was explained by land-cover features and stream elevation. We compiled segment-level conditions to the HUC-12 and HUC-10 watershed scales to represent aquatic resource conditions hierarchically across 3 watershed-management scales. This process enabled us to relate stream-segment watershed conditions to watershed conditions in the broader context, and ultimately to identify key protection and restoration priorities in a metacommunity context. Our hierarchical classification system explicitly identifies stream restoration and protection priorities within a HUC-12 watershed context, which ensures that the benefits of restoration will extend beyond the stream reach. Highest protection priorities are high-quality HUC-12 watersheds adjacent to low-quality HUC-12 watersheds. Highest restoration priorities are HUC-12 watersheds in poor–fair condition within HUC-10 watersheds of good–excellent condition, whereas lowest restoration priorities are isolated HUC-12 watersheds. In high-priority HUC-12 watersheds, stream segments with the highest restoration priority are those that maximize watershed-scale restorability. A similar process for classifying conditions and restoration priorities may be valuable in other heavily impacted regions where strategic approaches are needed to maximize watershed-scale recovery.

A spatially explicit framework for quantifying downstream hydrologic conditions.

Continued improvements in spatial datasets and hydrological modeling algorithms within Geographic Information Systems (GISs) have enhanced opportunities for watershed analysis. With more detailed hydrology layers and watershed delineation techniques, we can now better represent and model landscape to water quality relationships. Two challenges in modeling these relationships are selecting the appropriate spatial scale of watersheds for the receiving stream segment, and handling the network or pass-through issues of connected watersheds. This paper addresses these two important issues for enhancing cumulative watershed capabilities in GIS. Our modeling framework focuses on the delineation of stream-segment-level watershed boundaries for 1:24,000 scale hydrology, in combination with a topological network model. The result is a spatially explicit, vector-based, spatially cumulative watershed modeling framework for quantifying watershed conditions to aid in restoration. We demonstrate the new insights available from this modeling framework in a cumulative mining index for the management of aquatic resources in a West Virginia watershed.

Scenario analysis predicts context-dependent stream response to landuse change in a heavily mined central Appalachian watershed

Abstract.  Scenario analysis has the potential to improve management of aquatic systems throughout the Mountaintop Removal–Valley Fill mining (MTR–VF) region of central Appalachia. However, the extent to which surface mining interacts with other landuse stressors (i.e., cumulative effects) is unclear, and this limits our ability to predict the effects of new mines on physical, chemical, and biological conditions downstream. We tested for additive and interactive effects of landuse change (surface mining, deep mining, and residential development) on water quality (specific conductance and Se), habitat quality, and benthic macroinvertebrates via a uniquely designed watershed-scale assessment of the Coal River, West Virginia (USA). We derived equations for predicting in-stream response to landscape changes and predicted the outcome of a realistic future scenario involving development of 15 permitted mines. Elevated Se concentrations were directly correlated with incremental increases in surface-mining extent. Surface mining, deep mining, and residential development had additive effects on elevated specific conductance and reduced biological condition. We found evidence of a positive interactive effect (stressor antagonism) of deep mining and residential development on biological condition, presumably caused by stream-flow augmentation from deep mines. Landscape context influenced predicted impacts from construction of 15 new mines because of additive and interactive effects of landuse change. New surface mines increased the number of receiving streams exceeding chemical and biological criteria, but a greater proportion of receiving streams exceeded chemical and biological criteria at equivalent levels of new mine development when pre-existing stressors were present. When surface mining was the only stressor, ≥30 or 40% increases in surface mining caused 100% of streams to exceed chemical or biological standards, respectively, whereas in streams stressed by deep mining and residential development, ≥10% additional surface mining caused 100% of streams to exceed chemical and biological standards. Continued progress in this area will require a better understanding of how landuse change affects aquatic systems in the rest of the MTR–VF mining region, where watershed-to-watershed variation in landuse patterns probably causes variability in ecological response.