Potomac Basin Research Articles

Evaluation of reported and unreported water uses in various sectors of the Potomac basin for the year 2017

AbstractWater resource planners and managers in the Mid‐Atlantic United States typically determine the sufficiency of water supplies to meet demand by comparing (1) water use as reported to the state by individual water users to (2) metrics of water availability calculated from observed water monitoring networks. This paper focuses on determining whether this means of measuring water use is sufficient for proactive and sustainable management of water resources. The Potomac basin study area illustrates the point that, while state‐reported water use databases typically cover the largest individual water users, unreported water uses can cumulatively comprise a substantial portion of the overall water use. If left unaccounted for, the system is vulnerable to human demand exceeding supplies, with attendant detrimental effects to aquatic habitats and organisms, especially given the exacerbating effects of climate change on the variability of water supplies. Planners and managers are therefore encouraged to consider the full spectrum of water uses, regardless of state reporting requirements.

Using Published Information to Predict Consumption by Northern Snakehead in Maryland

AbstractThe Northern Snakehead Channa argus, a species originating from Asia, was illegally introduced into ponds of Maryland in 2002. Later discovered in tidal freshwater of the Potomac River, the species has become successfully established in many Maryland rivers. The magnitude of impact on preferred prey of Northern Snakehead in North American ecosystems has not been widely studied, leaving unresolved whether there are deleterious effects owed to introduction. To add insight into potential impacts of Northern Snakeheads, we calibrated a published, temperature‐dependent maximum consumption model using field data and informed its results with diet and prey preference data to compare consumption levels among prey species. The total annual maximum consumption estimated from the model for a population of 600 Northern Snakeheads, which is an abundance approximated from published population sizes in streams of the Potomac basin, amounted to consumption of 2,189 kg of fish for the population per year. We found no evidence of strong prey preferences and partitioned this consumption to relative proportions of some fishes preyed on by Northern Snakehead as 661 kg/year of sunfishes Lepomis spp., 522 kg/year of Yellow Perch Perca flavescens, 332 kg/year of Goldfish Carassius auratus, 250 kg/year of White Perch Morone americana, and 174 kg/year of Banded Killifish Fundulus diaphanus. Some of these coastal fishes comprise important recreational and commercial fisheries. The maximum consumption estimates modeled here are greater than would be observed naturally, and whether predation affects persistence of the prey species in the ecosystem will depend upon the resiliency of the prey population and its current population size, which are unknown. We conclude that, as indicated by earlier risk assessments, the Northern Snakehead is an important predator in Maryland ecosystems because it is opportunistic and is capable of consuming significant biomasses of several recreationally and commercially important fish species.

Genetic Haplotype Mapping of the Allegheny Crayfish (Faxonius obscurus)

Non-indigenous species are a significant threat to freshwater biodiversity. In the Potomac Basin there are several known invasive crayfish species including F. virilis (virile crayfish) and F.rusticus (rusty crayfish). It is imperative to discover whether F. obscurus is in fact an invasive crayfish that needs a management plan or simply another native species that needs protection. F. obscurus is a wide-ranging crayfish species that is native to the northeastern United States. Populations found in the Atlantic Slope Drainage basins are considered invasive. Using CO1 and 16S primers, we will be creating a range-wide haplotype map to investigate these invasions.

Integrating Sustainable Water Resource Management and Land Use Decision-Making

Human uses of land and water are directly linked and must, therefore, be managed with each other in mind. This paper puts forward an approach for integrating sustainable water resource management into local land use decision-making in the Potomac basin. The approach includes developing a clear understanding of the current regulatory, programmatic, and financial approaches to land use management; identifying opportunities from innovation; and developing a flexible, stakeholder-based framework for moving forward. Four opportunities for innovation were identified in the Potomac basin utilizing this approach, including enhancing coordination and access to information, promoting incentives to achieve desired outcomes, encouraging and promoting innovation, and integrating programs to achieve multiple objectives. The successful integration of land and water decision-making requires a sustained, long-term commitment to improvement rather than a one-time fix mentality. Initial steps for implementation include identifying and engaging diverse partners, as well as establishing channels for information dissemination. The lessons learned from this work may prove valuable to decision-makers in other regions to holistically manage diverse land and water resources.

Response of shallow subterranean freshwater amphipods to habitat drying

The ability of three amphipods that occupy shallow subterranean habitats in the lower Potomac Basin of the US (hypotelminorheic), which often dry out seasonally, to withstand desiccation by burrowing in clay was investigated. Both Crangonyxshoemakeri, a wetland species, and Stygobromustenuis, a subterranean species, burrowed in clay in the laboratory after surface water was removed. Gammarusminus, a spring species, did not. All three species exhibited behavioral changes as the habitat dried out.

Shells below, stars above: four perspectives on shell beads

ABSTRACTIn the papers assembled here, five scholars focus on shell beads at site, watershed, and regional scales. Themes include manufacturing techniques such as bore size discussions, changes in bead preferences over time and geography, the appearance of beaded regalia, and shell bead meaning. Claassen’s paper addresses the beads at Late Archaic Indian Knoll; Connaway discusses shell beads in northwestern Mississippi; Pearson looks at beads from coastal Georgia; and Webster and King examine beads before and after European contact in the Potomac basin.

Streamflow Alteration from Impervious Cover: Are All Watersheds Created Equal?

AbstractVery small amounts of impervious cover can impact streamflows. In the Potomac basin, for example, significant streamflow alteration associated with watershed impervious cover >0.5%–2.0% have been found. Since these impacts were found with considerably lower amounts of impervious cover than previously documented in the literature, typically 10%–20%, this study evaluated whether certain watershed characteristics (e.g., watershed area, karst geology, precipitation, soil characteristics, physiographic province, and slope) make a stream reach more susceptible to the impacts of impervious cover than others. The results of this study indicate there are differences in streamflow sensitivity to impervious cover given certain landscape characteristics. The relationships of watershed characteristics with streamflow alteration in flashiness, high flow duration, and low pulse duration were evaluated. Flashiness alteration was positively correlated with impervious cover and influenced by watershed slope and area. High flow duration alteration was negatively correlated with impervious cover and influenced by mean annual precipitation and slope. Low pulse duration was poorly correlated with the watershed characteristics under consideration. These differences may assist in land management efforts and heighten awareness of the environmental impacts of impervious cover.

Northern Snakeheads in New York City

Abstract A population of Channa argus (Northern Snakehead) was discovered in the Meadow/Willow lakes system in Queens, NY, in 2005 and monitored annually by electrofishing through 2013. Despite apparently suitable habitat, a variety of forage fish species, and rapid early growth by Snakeheads, the Meadow/Willow Snakehead population has not rapidly increased, as seen in many other areas, nor is there any evidence of negative impact on local species. Catch-per-unit-effort (CPUE) of Snakeheads remained relatively constant during the study period, as did CPUE for most other fish species observed, and Snakehead length—weight relationship was nearly identical to that previously reported from the Potomac Basin Northern Snakehead population. Potential causal factors in this lack of (or delay in) population increase include water quality, the presence of other fish species, and angling pressure, although the exact reasons for slow population growth are unknown.

A new method for tracking poultry litter in the Potomac Basin headwaters of West Virginia

To validate the distribution of a poultry litter-specific marker gene in faecally contaminated environmental waters of an intensive poultry litter rearing region. A TaqMan(®)-based qPCR assay for Brevibacterium sp. LA35 16S rRNA (LA35 gene), which was previously shown to be associated with poultry litter and faeces, was tested on 126 nontarget faecal samples and 28 poultry litter and faecal samples. The TaqMan assay was sensitive (76%) and specific (100%) to the LA35 gene and exhibited a detection limit for poultry litter in water samples that is sufficiently low (2.5 × 10(-2) mg litter l(-1)) to be applicable for environmental monitoring. The LA35 gene was detected in 43% of water samples (n = 30) collected in an intensive poultry rearing region of West Virginia which drains to the Chesapeake Bay. The poultry-specific TaqMan qPCR method for the LA35 gene is more specific than previously published methods and can be used to identify regions impacted by poultry rearing activities. The LA35 gene appears to have a broad geographical distribution as it has been found in poultry litter and faeces from Delaware and West Virginia, in this study and from Arkansas, Georgia, Florida, Minnesota, Oklahoma and Utah previously.

Chemical contaminants in water and sediment near fish nesting sites in the Potomac River basin: Determining potential exposures to smallmouth bass (Micropterus dolomieu)

The Potomac River basin is an area where a high prevalence of abnormalities such as testicular oocytes (TO), skin lesions, and mortality has been observed in smallmouth bass (SMB, Micropterus dolomieu). Previous research documented a variety of chemicals in regional streams, implicating chemical exposure as one plausible explanation for these biological effects. Six stream sites in the Potomac basin (and one out-of-basin reference site) were sampled to provide an assessment of chemicals in these streams. Potential early life-stage exposure to chemicals detected was assessed by collecting samples in and around SMB nesting areas. Target chemicals included those known to be associated with important agricultural and municipal wastewater sources in the Potomac basin. The prevalence and severity of TO in SMB were also measured to determine potential relations between chemistry and biological effects.A total of 39 chemicals were detected at least once in the discrete-water samples, with atrazine, caffeine, deethylatrazine, simazine, and iso-chlorotetracycline being most frequently detected. Of the most frequently detected chemicals, only caffeine was detected in water from the reference site. No biogenic hormones/sterols were detected in the discrete-water samples. In contrast, 100 chemicals (including six biogenic hormones/sterols) were found in a least one passive-water sample, with 25 being detected at all such samples. In addition, 46 chemicals (including seven biogenic hormones/sterols) were found in the bed-sediment samples, with caffeine, cholesterol, indole, para-cresol, and sitosterol detected in all such samples.The number of herbicides detected in discrete-water samples per site had a significant positive relation to TOrank (a nonparametric indicator of TO), with significant positive relations between TOrank and atrazine concentrations in discrete-water samples and to total hormone/sterol concentration in bed-sediment samples. Such significant correlations do not necessarily imply causation, as these chemical compositions and concentrations likely do not adequately reflect total SMB exposure history, particularly during critical life stages.

“Typically American”

“Typically American”

A Multi-Taxa Biological Survey of Passage Creek, Virginia

Identifying and conserving functioning headwater ecosystems is essential for ensuring the structure and function of natural ecosystem processes. The Passage Creek watershed (PCW) in Virginia is an upland tributary system of the North Fork Shenandoah River, which is found within the Potomac River basin. The PCW appears to maintain an array of terrestrial and fluvial habitats now uncommon in many adjacent watersheds because of human disturbance. We assessed the biotic condition of the PCW by sampling the fish, mollusk, and salamander assemblages throughout the watershed. We observed 29 fish, 9 salamander, and 4 aquatic mollusk species representing a variety of life histories and functional groups. Furthermore, we found that due to spatial differences in abundance and species richness, each assemblage offered unique insight into the condition of the PCW. The fish assemblage was indicative of those found in least disturbed areas within the Potomac basin, while salamander abundance and richness indicated areas of habitat degradation. Though we observed only one mussel species, the presence of native mussels suggested the PCW has maintained sufficient ecological condition to support long-lived animals potentially sensitive to low-level, additive, and compounding long-term disturbances, while neighboring watershed assemblages have collapsed. Given the relatively high species richness found within PCW, this watershed may be pivotal to the overall persistence of aquatic species in the Potomac basin and should receive high priority for future conservation efforts.

Rescued from Synonymy: A Redescription of Percina bimaculata Haldeman and a Molecular Phylogenetic Analysis of Logperch Darters (Percidae: Etheostomatinae)

Percina nebulosa and Percina bimaculata have been considered synonyms of P. caprodes for over 130 years. The taxonomic history of P. nebulosa is complicated by the fact that the name is preoccupied by Perca nebulosa Rafinesque. Percina bimaculata Haldeman is the available and appropriate name for this species, and the Chesapeake Logperch is the proposed common name. Recent phylogenetic analyses of mitochondrial DNA gene sequences support the hypothesis that P. bimaculata is a distinct species; however, a morphological comparison between P. bimaculata and other logperch darter species has never been published. An examination of morphological characters and a new molecular phylogeny of both mitochondrial and nuclear gene sequence data support the recognition of P. bimaculata as a distinct species most closely related to P. kathae and P. austroperca. Historically, P. bimaculata was distributed in the lower Susquehanna River Basin of Pennsylvania and Maryland and the middle to lower Potomac River Basin of Maryland, Virginia and the District of Columbia, USA. The species has not been recorded from the Potomac Basin since the 1930s and is currently found only in the lower Susquehanna River Basin. The restricted geographic distribution and extirpation from the Potomac Basin indicates that P. bimaculata is an imperiled species and may warrant protection under the Endangered Species Act of 1973. The molecular phylogeny also indicates that populations recognized as P. caprodes sampled from the upper Mississippi River Basin in Illinois, Wisconsin and Minnesota are not closely related to P. caprodes populations sampled from the Ohio, Tennessee, White and Hudson river drainages.

Data synthesis and bioindicator development for nontidal streams in the interstate Potomac River basin, USA

Water resource agencies are increasingly confronted with issues of methods and data comparability when assessing inter-jurisdictional waters. The Interstate Commission on the Potomac River Basin (ICPRB) is developing an assessment framework for the diverse nontidal monitoring data collected by Potomac basin jurisdictions. The ICPRB's goal is to augment the jurisdictions’ water quality assessments with uniform, basin-wide evaluations of habitat and biological integrity. Disparate datasets were integrated and used to select and calibrate a common suite of biological indicators of human disturbance. Aggregated physiographic regions were most effective at grouping streams into site classes with similar attributes. Common elements from states’ habitat and water quality assessments were used to define regional reference and impairment criteria. Seven macroinvertebrate metrics distinguished reference from impaired sites in most regions: EPT richness, Hilsenhoff Family Biotic Index, percent clingers, percent collectors, percent dominance, percent EPT, and taxonomic richness. Reference communities in the Piedmont region of the basin were dissimilar from those in Highland and Valley regions, suggesting a need for different reference conditions and metric thresholds in these regions. Results confirm that useful bioindicators of aquatic health can be generated from multiple datasets if the synthesis is done with care.

Small Sample Properties of H and K—Estimators of the Hurst Coefficient h

Seasonal differences in long‐term persistence (h > 0.5), were found for 25 streams in the Potomac River basin. Two statistics, H and K, used as estimators of h were found to have differing small sample properties. K was found to have less variance but a greater positive bias than H. However, the Hurst phenomenon, in which H and K values differ from the expected values for independent series, was confirmed for the Potomac River basin streamflows. Neither marginal distribution nor biased transience appear to be viable explanations for the differences between observed and independent or short memory simulated sequences. For the Potomac basin, the explanation of h > 0.5 can only be attributed to the nature of the correlation structure of the observed series.

Coal Measures of Maryland

AREA The Coal Measures are found in Allegany and Garrett counties, Maryland, situated in the western part of the State, where they underlie a large part of the region between the Alleghany front and the West Virginia-Maryland State line. The strata occupy three major structural troughs whose axes trend northeast-southwest, parallel to the trend of the mountains. The most westerly trough is called the Lower Youghiogheny, or Friendsville, basin. The middle basin is divided into two parts by a transverse minor anticline, thus forming the Upper Youghiogheny basin on the southwest and the Castleman basin on the northeast. The eastern trough is cut into two parts by the Potomac River, which turns across it at Piedmont, the southern extension of the basin being known as the Upper Potomac basin and the northeastern as the Georges Creek basin. The relations of these basins are shown in the accompanying map. The investigation of . . .

The Hydrography of the Potomac Basin

The Hydrography of the Potomac Basin

Discussion on Hydrography of the potomac Basin

Discussion on Hydrography of the potomac Basin