Kentucky Streams Research Articles

Scale associated coupling between channel morphology and riparian vegetation in a bedrock-controlled stream

Most fluvial systems exhibit systematic, continuous upstream to downstream variations in channel morphology and related ecological and hydrological parameters (emphasized by conceptual frameworks such as downstream hydraulic geometry and the river continuum concept), and discontinuous, shorter range variations (emphasized by hierarchical patch dynamics). This study investigates the relative importance of broader-scale upstream to downstream variation and local variation at the hydraulic unit scale in a bedrock-controlled stream in central Kentucky, USA. A nested ANOVA analytical approach was used to determine the relative importance of three nested spatial scales in explaining variations in channel morphology and riparian trees. Results show that channel morphology is largely controlled by local-scale variation explaining about 92% of slope, 46% of bankfull width, 99% of average depth, 54% of width-depth ratio, 86% of channel cross-sectional area, and 100% of the hydraulic radius of the channel. Different categories of substrate characteristics, however, represent anomalies with respect to variance explained at different levels. Furthermore, local-scale controls explain 60% of variations in species richness, 59% of variations in the total number of individual trees, 68% of variation in the proportion of Platanus occidentalis basal area and 43% of variation in the total number of biogeomorphic impacts. These results are consistent with the idea of tight coupling between channel morphology and riparian vegetation, although they do not, by themselves, prove such interactions. The morphological variation of the channel at the local scale is primarily attributable to the geological controls (e.g., faults, bedding planes, joints and fractures) and incision status associated with the study area. The local scale variation in vegetation pattern can be explained by the highly local edaphic differences along the riparian corridor, which is likely to be related to the local scale fluvial process-form variations, and biogeomorphic impacts and feedbacks. These patterns may therefore be common in bedrock rivers strongly influenced by geological controls.

Evaluating Snake Density Using Passive Integrated Transponder (PIT) Telemetry and Spatial Capture–Recapture Analyses for Linear Habitats

Many snake species are elusive and difficult to study in field settings. As such, little is known about their population ecology despite conservation needs for many species. Advances in field techniques and statistical methods can improve our understanding of snake ecology. We used passive integrated transponder (PIT) telemetry to track Nerodia sipedon (Northern Watersnakes, n = 94) and Regina septemvittata (Queensnakes, n = 119) in six low-order streams in central Kentucky, USA from June to October 2016. We assessed snake density, spatial scale of detection, and detection probability using PIT tag relocations and spatial capture–recapture methods for linear habitats. Specifically, we modeled population density as a function of individual stream and land cover type, spatial scale of detection as a function of sex, and detection probability as a function of sex and time-varying covariates. Individual streams were a better predictor of snake density than land cover type; density estimates ranged from 6 ± 3 N. sipedon/km (mean ± standard error) to 107 ± 17 N. sipedon/km and 6 ± 5 R. septemvittata/km to 63 ± 10 R. septemvittata/km. Female R. septemvittata had a larger spatial scale of detection (55 ± 4 m) than male R. septemvittata snakes (40 ± 4 m). Spatial scale of detection did not differ between sexes for N. sipedon (females: 40 ± 4 m; males: 35 ± 3 m). The combination of PIT telemetry and spatial capture–recapture analyses can effectively estimate population densities and other population parameters for snakes and other reptiles and amphibians associated with linear habitats.

Local efficiency in fluvial systems: Lessons from Icicle Bend

Development of fluvial systems is often described and modeled in terms of principles related to maxima, minima, or optima of various hydraulic or energy parameters that can generally be encompassed by a principle of efficiency selection (more efficient flow routes tend to be preferentially selected and enhanced). However, efficiency selection is highly localized, and the cumulative effects of these local events may or may not produce more efficient pathways at a broader scale. This is illustrated by the case of Icicle Bend on Shawnee Run, a limestone bedrock stream in central Kentucky. Field evidence indicates that a paleochannel was abandoned during downcutting of the stream, and the relocation was analyzed using a flow partitioning model. The bend represents abandonment of a steeper, straighter, more efficient channel at the reach scale in favor of a longer, currently less steep and less efficient flow path. This apparently occurred owing to capture of Shawnee Run flow by a subsurface karst flow path that was subsequently exhumed. The development of Icicle Bend illustrates the local nature of efficiency selection and the role of historical contingency in geomorphic evolution.

Macroinvertebrate and organic matter export from headwater tributaries of a Central Appalachian stream

Headwater streams export organisms and other materials to receiving streams, and macroinvertebrate drift can shape colonization dynamics in downstream reaches while providing food for downstream consumers. Spring-time drift and organic matter export was measured once monthly (February–May) over a 24-h period near the outlets of 12 eastern Kentucky (USA) streams to document and explore factors governing downstream transport. We compared drift measures as loads (day−1) and concentrations (volume−1) including drift density, biomass, richness, composition, and particulate organic matter across catchment area, month, reach scale factors, and network proximity. Aquatic invertebrate drift densities were roughly 10 times greater than terrestrial invertebrate densities; aquatic richness ranged from 18 to 45 taxa with Ephemeroptera, Plecoptera, Trichoptera, and Diptera genera dominating drift sample richness and abundance. Ordination revealed that assemblages clustered by month and catchment area; organic matter exports (loads or concentrations) also varied by month and catchment area factors. While drift measures were correlated with catchment area and sample date, local factors (e.g., substrate composition, riffle length, channel slope, and network proximity) were generally non-influential. The findings can be used to inform preservation and restoration strategies where headwater streams serve as sources of colonizers and provide food subsidies to receiving streams.

Using Geomorphic Data to Develop a Stability Index for Northern Kentucky Streams

Using Geomorphic Data to Develop a Stability Index for Northern Kentucky Streams

A terrestrial invader threatens a benthic community: potential effects of hemlock woolly adelgid-induced loss of eastern hemlock on invertebrate shredders in headwater streams

The invasion of non-native species is considered among the most important causes of the loss of native biota. An example of a devastating exotic pest impacting eastern forests is the hemlock woolly adelgid (HWA) (Adelges tsugae), a xylem feeding insect native to Asia that feeds on all ages and species of hemlock (Tsuga spp.), and has the capacity to functionally eliminate eastern hemlock (T. canadensis) from the landscape. Eastern hemlock is an important component of forested riparian communities in southern and central Appalachia where it maintains stable stream conditions important for aquatic biota. We investigated differences between eastern hemlock and deciduous dominated headwater streams in eastern Kentucky to determine the extent to which HWA invasion may affect benthic invertebrate shredders. Shredders form the basis of a resource chain within headwater streams, thus they are invaluable links in stream-riparian interactions. We found that eastern hemlock contributed energy in the form of leaf litter to the riparian zone at a consistent rate throughout the growing season in contrast to the autumnal pulse of deciduous material. We also detected significant vegetation by season interactions for shredders which suggest that some shredders are more abundant in eastern hemlock streams than in their deciduous counterparts during the summer. This could be linked to the consistent addition of food resources that eastern hemlock provides. Our results indicate that stream communities will likely change following adelgid associated mortality of eastern hemlock in headwater stream riparian zones.

Cryptic phenotypic plasticity in populations of the North American freshwater gastropod, Pleurocera semicarinata

BackgroundPhenotypic plasticity is termed ‘cryptic’ when it becomes so extreme as to prompt an (erroneous) hypothesis of speciation. Populations of pleurocerid snails nominally identified as Pleurocera (‘Goniobasis’ or ‘Elimia’) livescens are common elements of the macrobenthos in rivers and on lakeshores from Vermont through northern Ohio and northern Indiana to Wisconsin, USA. Small streams in southern Ohio, southern Indiana, and Kentucky are inhabited by Pleurocera semicarinata, and larger rivers by Lithasia obovata. The three nominal species differ only in qualitative aspects of shell morphology - P. semicarinata demonstrating a slender shell with a small body whorl, L. obovata a robust shell with a large body whorl, and P. livescens intermediate.ResultsHere I use allozyme electrophoresis to estimate genetic divergence over 11 enzyme loci among three populations of P. livescens, two populations of P. semicarinata, and one population of L. obovata sampled across 650 km of their combined range. With each of these six populations I sample a control population of Pleurocera canaliculata, demonstrating that the genetic divergence among the six known conspecific populations is comparable to that observed among the six study populations.ConclusionsThe specific nomina L. obovata and P. livescens would appear to be junior synonyms of P. semicarinata. The shell morphological differences by which these taxa have heretofore been distinguished would appear to result from ecophenotypic plasticity, driven perhaps by predation, substrate, or current.

Nest Association and Reproductive Microhabitat of the Threatened Blackside Dace, Chrosomus cumberlandensis

Abstract Chrosomus cumberlandensis (Blackside Dace) is a federally protected cyprinid fish found in small tributaries of the upper Cumberland River system in southeastern Kentucky and northeastern Tennessee. Relatively little is known about the species’ reproductive ecology and early life history. From a small number of field observations, the species is known to spawn as an associate with other cyprinid nest-building hosts, namely Campostoma anomalum (Central Stoneroller) and Semotilus atromaculatus (Creek Chub). In the present study, we first analyzed Blackside Dace co-occurrence patterns with other cyprinids to predict the relative importance of each species to Blackside Dace nestassociation behavior. We next studied Blackside Dace spawning activities in seven 200-m reaches in five Kentucky streams during May-July 2006 to document nest associations and measure microhabitat conditions at spawning and non-spawning locations. Three of the seven study reaches were impacted by active logging operations. We ...

Specific conductivity sensor performance: I. Laboratory evaluation

The focus on specific conductivity in the Central Appalachian Coal Fields of the USA has highlighted the need to obtain accurate specific conductivity measurements, particularly in light of the US Environmental Protection Agency (USEPA) guidance that water discharged from mine sites in this region should have specific conductance levels less than 300–500 μS cm−1. Being able to accurately determine the specific conductance levels of mine discharged waters has significant implications for the USEPA as well as mine operators particularly when specific conductance levels approach this designated threshold. Presently, a number of sensors are available on the market for recording specific conductance measurements; however, a detailed study comparing sensor performance under controlled conditions (e.g. temperature and specific conductance levels) has not been performed. This paper compares the performance of four commonly used sensors YSI 6600 V2-4 data sonde, HOBO U-24-001, Solinst Model 3001 LTC Levelogger Junior, and In-situ Aqua TROLL 100. Results of this laboratory study indicated that for conditions more frequently encountered in Kentucky streams, the HOBO and Solinst sensors were most accurate.

Specific conductivity sensor performance: II. Field evaluation

The US Environmental Protection Agency (USEPA) has issued guidance on the specific conductivity (EC25°C) of waters discharged from mined lands in the Appalachian Coal Belt Region of the USA. In this guidance, the USEPA states that these waters should have an EC25°C less than 300–500 μS cm−1. Such a requirement places great importance on accurately determining EC25°C. Building upon a laboratory-based evaluation of four types of commercially available continuous logging conductivity sensors, this study examined sensor performance in the more harsh and variable field environments at forested and mined land streams in eastern Kentucky. The objectives of this study were to calculate the white noise variance associated with each sensor type and to evaluate white noise variance in relation to variations in EC25°C and discharge. Results of the study indicate that predominant increases in EC25°C, and to some extent increases in discharge, explain between 35 and 65% of the white noise variance.

Two unusual new species of Kongsbergia (Acari: Hydrachnidiae: Aturidae) from eastern North America

An ongoing revisionary study of the North American species of Kongsbergia has revealed two new species that are apparently not closely related to others on the continent. Adults of Kongsbergia torosa sp. nov. are described from streams in Ontario (Canada) and Kentucky and North Carolina (USA) and adults of Kongsbergia tishomingo sp. nov. are described from a stream in Mississippi (USA).

Estimation of Suspended-Sediment Concentration From Total Suspended Solids and Turbidity Data for Kentucky, 1978-19951

Williamson, Tanja N. and Charles G. Crawford, 2011. Estimation of Suspended-Sediment Concentration From Total Suspended Solids and Turbidity Data for Kentucky, 1978-1995. Journal of the American Water Resources Association (JAWRA) 47(4):739-749. DOI: 10.1111/j.1752-1688.2011.00538.x Abstract: Suspended sediment is a constituent of water quality that is monitored because of concerns about accelerated erosion, nonpoint contamination of water resources, and degradation of aquatic environments. In order to quantify the relationship among different sediment parameters for Kentucky streams, long-term records were obtained from the National Water Information System of the U.S. Geological Survey. Suspended-sediment concentration (SSC), the parameter traditionally measured and reported by the U.S. Geological Survey, was statistically compared to turbidity and total suspended solids (TSS), two parameters that are considered surrogate data. A linear regression of log-transformed observations was used to estimate SSC from TSS; 72% of TSS observations were less than coincident SSC observations; however, the estimated SSC values were almost as likely to be overestimated as underestimated. The SSC-turbidity relationship also used log-transformed observations, but required a nonlinear, breakpoint regression that separated turbidity observations ≤6 nephelometric turbidity units. The slope for these low turbidity values was not significantly different than zero, indicating that low turbidity observations provide no real information about SSC; in the case of the Kentucky sediment record, this accounts for 30% of the turbidity observations.

Potential of Breakthroughs of Impounded Coal Refuse Slurry into Underground Mines

On October 11, 2000, an estimated 306 million gallons of water and fine coal refuse slurry broke through a bedrock barrier from an impoundment in Martin County, eastern Kentucky, into an adjacent underground mine. Approximately 260 million gallons of the water and coal slurry discharged from two underground mine portals and affected over 75 miles of streams in Kentucky and West Virginia. As a result of this and several other breakthroughs over just half a decade, the U.S. Office of Surface Mining Reclamation and Enforcement (OSM) and other institutions undertook investigations to assess the causes of the events, the potential for additional breakthroughs in the future, and available methods for preventing them. In addition to needed improvements in the design, construction, and inspection of the facilities, the studies have addressed issues pertaining to the flow characteristics of refuse slurry, not only in impoundments still receiving pumped slurry, but also in “idle” and reclaimed facilities. Related questions concern: (1) the effects on breakthrough potential of the impoundment abandonment process and construction of slurry cells on top of capped structures; and (2) appropriate measures and available methods that may be used to ensure that underground mines adjacent to or underlying impoundments are known and accurately located. Current information on the engineering properties of coal refuse in existing facilities provides no assurance against fine refuse flowability during any stage in the impoundment construction and reclamation process or after reclamation has been completed. Due to this uncertainty, thorough site investigations and conservative measures in design, construction, reclamation, and quality control are of paramount importance.

Major Impacts and Challenges facing Kentucky's Streams and Wetlands: A Summary of Agency, Other Expert, and Stakeholder Views

Abstract To protect our nation's water resources, the United States Environmental Protection Agency (EPA) and the U.S. Army Corps of Engineers (USACE) have declared a goal of “no net loss” of our nation's water and wetland resources to be a national priority for the past 20 years. To meet this objective, the EPA has encouraged states to develop state wetland conservation plans and incorporate stakeholders into the development of those plans. Recently, the Kentucky Division of Water initiated a streams and wetlands conservation planning process. As part of the process, we conducted surveys and interviews of Kentucky stakeholders in stream and wetlands issues. Results of the surveys emphasized three impacts of concern: sewer overflows and straight pipes, coal and energy development, and residential growth. Stakeholders had wide areas of agreement, although their perspectives were not entirely uniform. Perception of the relative importance of some types of impacts was dependent on job position, level of awar...

Profile convexities in bedrock and alluvial streams

Longitudinal profiles of bedrock streams in central Kentucky, and of coastal plain streams in southeast Texas, were analyzed to determine the extent to which they exhibit smoothly concave profiles and to relate profile convexities to environmental controls. None of the Kentucky streams have smoothly concave profiles. Because all observed knickpoints are associated with vertical joints, if they are migrating it either occurs rapidly between vertical joints, or migrating knickpoints become stalled at structural features. These streams have been adjusting to downcutting of the Kentucky River for at least 1.3 Ma, suggesting that the time required to produce a concave profile is long compared to the typical timescale of environmental change. A graded concave longitudinal profile is not a reasonable prediction or benchmark condition for these streams. The characteristic profile forms of the Kentucky River gorge area are contingent on a particular combination of lithology, structure, hydrologic regime, and geomorphic history, and therefore do not represent any general type of equilibrium state. Few stream profiles in SE Texas conform to the ideal of the smoothly, strongly concave profile. Major convexities are caused by inherited topography, geologic controls, recent and contemporary geomorphic processes, and anthropic effects. Both the legacy of Quaternary environmental change and ongoing changes make it unlikely that consistent boundary conditions will exist for long. Further, the few exceptions within the study area–i.e., strongly and smoothly concave longitudinal profiles–suggest that ample time has occurred for strongly concave profiles to develop and that such profiles do not necessarily represent any mutual adjustments between slope, transport capacity, and sediment supply. The simplest explanation of any tendency toward concavity is related to basic constraints on channel steepness associated with geomechanical stability and minimum slopes necessary to convey flow. This constrained gradient concept (CGC) can explain the general tendency toward concavity in channels of sufficient size, with minimal lithological constraints and with sufficient time for adjustment. Unlike grade- or equilibrium-based theories, the CGC results in interpretations of convex or low-concavity profiles or reaches in terms of local environmental constraints and geomorphic histories rather than as “disequilibrium” features.

Use of Sunfish and Stoneroller Minnows as Real-Time In Situ Biomonitors of PCB Contamination in Freshwater Streams

A long-term polychlorinated biphenyl (PCB) monitoring study was conducted fortwo moderately impacted freshwater streams in Kentucky. Streamwater, sediment, and fish were analyzed for Aroclors 1248, 1254, and 1260 during 1988-2005. Only 8 of 263 water samples showed detectable PCBs. The low occurrences of PCB detections in streamwater indicated that PCBs were transitory in the water column, rapidly mobilizing into biotic and sediment compartments. One component of this study focused on species-specific patterns of PCB residues in fish, especially the green sunfish (Lepomis cyanellus), longear sunfish (L. megalotis), bluegill (L. macrochirus), and stoneroller minnow (Campostoma anomalum). Stoneroller minnows had higher PCB concentrations and increased frequency of detection when compared to sport fish. Aroclor 1248 was detected 80% of the time in stoneroller minnows from Big Bayou creek, whereas it was only detected in 25-39% of sport fish. In comparison, Aroclors 1254 and 1260 in sport fish were detected 49-69% of the time. These results indicate that higher chlorinated PCB congeners found in Aroclors 1254 and 1260 were not as readily metabolized and excreted by sport fish. No relationships were found between sunfish age and PCB concentrations, which demonstrated that sunfish exposed to low PCB contamination can effectively regulate PCBs, regardless of age. In addition, at low PCB levels (<0.50 microg/g), green sunfish body burden did not correlate with lipid content. A certain PCB threshold concentration, > or = 1.00 microg/g, must be exceeded before correlations between PCB body burden and lipid content are observed. These results indicate that, at least for species such as the sunfish, the use of the octanol-water partition coefficient (Kow) under low-level PCB exposure would appear to have little predictive value. Studies by Sanborn et al. (1975) found the green sunfish to be particularly adept at metabolizing organochlorine compounds and PCBs. This field study supports their laboratory findings. Green sunfish may have an enhanced P450 system, or due to low body lipid content, more effectively shunt PCBs into metabolic pathways that detoxify these compounds.

NEW DISTRIBUTION RECORDS OF FISHFLIES (MEGALOPTERA: CORYDALIDAE) FOR KENTUCKY, U.S.A

New distributional records (74) of larval fishflies are reported for Kentucky. Twenty-five new county records were added for Nigronia serricornis (Say), and forty-two new county records were added for N. fasciatus (Walker), the most widely distributed fishfly in Kentucky (54 counties). These two species were sympatric in 14 streams in eastern Kentucky. One new county record was added for Neohermes concolor (Davis). Four new county records were noted for Chauliodes pectinicornis (Linnaeus), while two new county records were added for C. rastricornis Rambur. Following this investigation, the statewide distribution of fishfly species is as follows: N. serricornis (51 counties), N. fasciatus (54 counties), N. concolor (11 counties), C. pectinicornis (9 counties), and C. rastricornis (9 counties). Emergence patterns are mentioned for the five species of fish-flies in Kentucky.

Effectiveness of stream restoration following highway reconstruction projects on two freshwater streams in Kentucky

After new highway construction near or across a stream, the site often requires remediation to reestablish suitable habitat for local biota. This study addresses effectiveness of environmental mitigation efforts for these construction projects, and contributes to the development of a protocol for environmental mitigation to be adopted by the Kentucky Transportation Cabinet. Effects of remediation on two small KY, USA, streams, Cedar Creek and Holts Creek, were assessed using U.S. EPA Rapid Bioassessment Protocols (RBP). Habitat assessments and fish species assemblage surveys (index of biotic integrity) were conducted for three sectors of each stream. A decrease in total habitat assessment scores was observed at the remediated sector in each stream. However, for both streams the IBI fish assemblage scores were similar for upstream and remediated sectors, indicating that habitat impact resulted in limited effects on fish assemblages. The overall score for the downstream reach of Cedar Creek also was similar to upstream and remediated sectors, but the downstream portion of Holts Creek scored lower, primarily because of reduced number of fish species and abundances. This was likely due to stream characteristics and lack of diversity. The U.S. EPA Rapid Bioassessment Protocols proved to be well suited for quantitative assessments of fish assemblages for small stream sectors with limited impacted areas. Although habitat quality scored somewhat lower in the remediated sectors of both streams, there were no major impairments of overall stream productivity and no apparent blockage of fish migration. The most apparent deficiencies in habitat restoration involved protective and riparian vegetation, resulting in diminished bank stability, increased prospects for bank erosion, moderate downstream siltation, and consequences of stream channelization.

Effects of Fish on the Local Abundance of Crayfish in Stream Pools

A survey of fish and crayfish distributions in pools in small Kentucky streams suggested that predatory fish have strong effects on the local distribution of crayfish. I tested this hypothesis by experimentally manipulating the density of fish in stream pools. The predator, green sunfish (Lepomis cyanellus), strongly reduced the density of crayfish (Cambarus bartoni). Prey movement rates into and out of pools were low compared to estimated predation rates: consequently. I concluded that observed reductions of crayfish densities by fish predators were due mainly to direct consumption. Estimated rates of predation and prey movements were combined into a model to simulate observed predator impact on crayfish in patches larger and smaller than the scale of the experiment. The simulation suggested that the results were robust to increases in spatial scale. Data from the survey showed that crayfish densities in fish pools and fishless pools only differed for pools deeper than approximately 30-50 cm, probably because shallow pools had fewer and smaller fish. Thus, shallow pools provide a refuge for crayfish against fish. Very shallow pools (10-20 cm) generally had low densities of crayfish. Possible mechanisms that could explain the low density of crayfish in shallow pools include stronger effects of floods and higher predation pressure from terrestrial predators in these pools.

Habitat Selection by the Stream Mayfly Paraleptophlebia guttata

The causes and consequences of habitat distribution of larvae of the mayfly Paraleptophlebia guttata were analyzed in a 2nd-order stream in west-central Kentucky. Among macrohabitats, larvae were typically significantly more dense in runs and riffles than in pools. Densities were positively related to the percentage of coarse substrata in macrohabitats, but were not correlated with current velocity, predatory fish densities, or the quantity of fine particulate organic matter (food) in macrohabitats. This relationship between density and substratum coarseness was further evidenced in an in-situ colonization experiment in which larvae selected gravel and pebble substrata over sand. Among microhabitats, larvae were more abundant in leaf litter and in gravel/pebble than in silt/sand. Laboratory manipulations showed that predation rates by fish were significantly lower on mayflies in leaf litter and gravel than in fine substrata. The combined effects of substratum particle size and fish predation determine hab...