Litter decomposition in created and reference wetlands in West Virginia,USA

Large amounts of resources have gone into wetland mitigation in recent years; however, it is still unclear whether wetland function is being replaced along with wetland area. Litter decomposition is linked to numerous wetland functions. In this study, we measured plant litter decomposition potential over 12 months in 8 created and 8 reference wetlands located in the Allegheny Mountains of West Virginia, USA. Broadleaf cattail (Typha latifolia L.) litter bags were placed in each wetland and collected at 3 month intervals. Linear decomposition rate constants and percent mass remaining were similar between wetland types (created and reference) and among Cowardin classifications (palustrine: unconsolidated bottom, aquatic bed, emergent, and scrub/shrub). Created wetland age was not correlated with decomposition potential. Our study found that created wetlands had similar litter decomposition potential as reference wetlands indicating that similar processes are likely acting upon litter decomposition within both natural and created wetlands.     

Sublethal injuries in non-marine microconchid tubeworms from the Lower Carboniferous of West Virginia,USA

More than 10,000 non-marine microconchid tubeworms (order Tentaculita) from the Lower Carboniferous (Mauch Chunk Group) of West Virginian, USA, have been inspected with respect to the occurrence of specimens having repaired injuries. The inspection showed that only nine specimens bear distinct regenerations of their tubes which constitute only 0.08% of the total specimens. This value, although much lower than that obtained from other encrusting tentaculitoid tubeworms, is very similar to that calculated before for the thousands of Early Devonian planktonic tentaculitids. This clearly indicates that sample size (specimen number) is critical for obtaining the reliable data about the proportion of regenerated vs. unaffected specimens. The sublethal injuries present in these few individuals probably resulted from failed predation, most probably by grazing fishes. However, the repaired injuries only indicate that some individuals survived but do not provide any information about the predation intensity on the group in the given paleoenvironment. Microconchids encrusted a given substrate in large quantities, so grazing fishes may have easily removed the majority of individuals, leaving no trace of predation activity in the Early Carboniferous, non-marine paleoenvironments of what is now West Virginia.     

Chemical Contamination of California Drinking Water

Drinking water contamination by toxic chemicals has become widely recognized as a public health concern since the discovery of 1,2-dibromo-3-chloropropane in California''s Central Valley in 1979. Increased monitoring since then has shown that other pesticides and industrial chemicals are present in drinking water. Contaminants of drinking water also include naturally occurring substances such as asbestos and even the by-products of water chlorination. Public water systems, commercially bottled and vended water and mineral water are regulated, and California is also taking measures to prevent water pollution by chemicals through various new laws and programs.     

Public History,Private Memory: Notes from the Ethnography of Colonial Williamsburg,Virginia, USA

Colonial Williamsburg, and U.S. history museums generally, claim to transform public history into collective memory. That is, they convey an objective documented history to the public who, absorbing that history, acquires an appropriate collective or national memory. We argue that the emphasis on consumer (visitor) experience at such museums collapses the distance between the reconstructed past (the museum's history lesson) and the visitor's touristic or familial experience at the site. Visitors indeed remember their visits to Colonial Williamsburg, but their specific memories would seem to have little to contribute to any 'collective memory' of a 'national history.'     

Fine-scale biogeographic differences in the crustacean fauna of a cave system in West Virginia,USA

We examined the distribution patterns of four amphipod and one isopod crustaceans in 23 cave stream segments within a subterranean drainage basin. The patterns indicate that invasion history is a strong determinant of the species' distributions. One set of species likely has invaded the cave system from the zone of interstitial water, and thus is distributed mainly in headwater streams throughout the drainage. One species probably invaded through upstream migration from the resurgence of the cave system, and thus is strongly associated with the larger, higher-order streams. The effect of interspecific interactions on the patterns of distribution is not apparent at our scale of analysis.     

Water chemistry changes during artificial aeration of spruce Knob Lake,West Virginia

The water mass below 3.5 m in Spruce Knob Lake was artificially aerated with a modified full lift aerator during two consecutive summers (1974 and 1975) of an investigation that began in July of 1973 and ended in September, 1975. Artificial aeration increased water temperature below 3.5 m without causing destratification. Several chemical parameters were significantly affected by artificial aeration, especially from July to autumnal overturn in 1974 and 1975. Below 3.5 m, total inorganic carbon, total alkalinity, nitrite, soluble reactive phosphorus, and total phosphorus, were lower during aeration than in the summer of no aeration (1973). Although artificial aeration lowered soluble reactive and total phosphorus, there was no significant impact on the phosphorus budget of the impoundment. In 1975, continuous aeration from vernal overturn to autumnal overturn resulted in higher nitrate concentrations below 3.5 m than in the preceeding summers. Lower pH values encountered through the whole water column in 1975 followed a brief isothermal interruption of summer stratification in early June. There was no direct effect of artificial aeration on either temperature or water chemistry parameters in the epilimnion. Significantly lower chlorophyll concentrations observed in 1975 were related to destratification in June. Primary production was unaffected by aeration.     

Vegetative composition and community structure associated with beaver ponds in Canaan valley, West Virginia, USA

Beavers (Castor canadensis) can cause dramatic changes in vegetative composition and diversity. Although alterations by beaver have been studied extensively, little attention has been paid to the effects beaver impoundments have on rare plants. Effective conservation of riparian and wetland rare plant species must consider the responses of vegetation to changes in hydrology that can occur when beaver populations are present. The goal of this research was to establish the occurrence of locally rare plant species, examine community composition, and analyze vegetative community structure of vegetation associated with beaver ponds in Canaan Valley, West Virginia, USA. Species richness and diversity were similar between plots located inside beaver ponds and adjacent to beaver ponds (P > 0.05). Although no significant difference in rare plant species was detected among pond ages, the oldest ponds (>56 years) had twice as many rare species as the youngest ponds (≤6 years). The youngest ponds had higher overall mean species richness (S) than ponds 7–56 years old (P < 0.05), but S returned to similar levels in the oldest ponds. Of the 15 rare species observed, most were classified as obligate (9) or facultative wetland (4) species. The youngest ponds contained the fewest number of rare species. Multiple response permutation procedure (MRPP) analyses of community structure detected no relation between community composition and either pond age or size. However, both MRPP and non-metric multi-dimensional scaling showed proximity to pond was important in herbaceous community structure. Wetlands in beaver ponds also were shown to be distinct from adjacent wetland areas. Conservation of existing beaver populations is necessary so that the entire spectrum of pond ages is available for the maintenance of rare plant species and communities.     

Recommendations on minimum experimental plot size and succession of aphidophaga in West Virginia, USA, apple orchards

Five apple orchards in West Virginia, USA, were managed with five different pest management practices ranging from unsprayed to conventional insecticides. Data were collected on aphid, predaceous insect, and spider abundance every 2 weeks from May to July along one or two randomly selected, 15 consecutive tree transects. A total of 892 individual predaceous insects was observed: 32% wereAphidoletes aphidimyza, 21% wereCoccinella septempunctata and the rest were from 13 other taxa. The most important aphid predator seemed to beC. septempunctata. Of the 32 sample transects with predators, 72 % showed an edge effect in which either the standard error or mean of predator abundance differed from the edge towards the center of the orchard. This edge effect extended a mean of 7 trees (30 m) into the orchard. Only 39% of the 33 transects that had spiders showed an edge effect, extending into the orchard a mean of 8 trees (33 m). However, 75% of the transects with more than one spider per tree had an edge effect of 10 trees (43 m). We recommend a minimum border of seven trees before sampling for aphid predators and 10 trees before sampling for spiders. A recommended experimental plot size, for semi-dwarf, free-standing apple orchards, to eliminate edge effects is 1.25 ha for aphidophaga, 1.5 ha for spiders; a minimum plot size of 0.6 ha for aphidophaga and 0.75 ha for spiders would minimize edge effects.     

Peat and water chemistry at Big Run Bog,a peatland in the Appalachian mountains of West Virginia,USA

At Big Run Bog, aSphagnum-dominated peatland in the unglaciated Appalachian Plateau of West Virginia, significant spatial variation in the physical and chemical properties of the peat and in surface and subsurface (30 cm deep) water chemistry was characterized. The top 40 cm of organic peat at Big Run Bog had average values for bulk density of 0.09 g · cm^–3, organic matter concentration of 77%, and volumetric water content of 88%. Changes in physical and chemical properties within the peat column as a function of depth contributed to different patterns of seasonal variation in the chemistry of surface and subsurface waters. Seasonal variation in water chemistry was related to temporal changes in plant uptake, organic matter decomposition and element mineralization, and to varying redox conditions associated with fluctuating water table levels. On the average, total Ca, Mg, and N concentrations in Big Run Bog peat were 33, 15, and 1050 mol · g^–1, respectively; exchangeable Ca and Mg concentrations were 45 and 14 eq · g^–1 , respectively. Surface water pH averaged 4.0 and Ca⁺⁺ concentrations were less than 50 eq · L^–1 . These chemical variables have all been used to distinguish bogs from fens. Physiographically, Big Run Bog is a minerotrophic fen because it receives inputs of water from the surrounding forested upland areas of its watershed. However, chemically, Big Run Bog is more similar to true ombrotrophic bogs than to minerotrophic fens.     

Role of aphid predator guild in controlling spirea aphid populations on apple in West Virginia,USA

Spirea aphid populations and their predators were studied on apple to identify predators of importance in controlling aphid populations. Methods included random and non-random sampling from apple orchards in West Virginia, USA, sentinel aphid colonies, laboratory feeding studies, and predator exclusion studies. Aphidoletes aphidimyza (Diptera: Cecidomyiidae), chrysopids (Neuroptera: Chrysopidae), Harmonia axyridis (Coleoptera: Coccinellidae), and Orius insidiosus (Hemiptera: Anthocoridae) were the most abundant predators associated with spirea aphid colonies on apple. Parasitoids were all but absent in the study. Abundance of all predators was density dependent with greater responses to aphid populations at the orchard scale than to tree or individual colony scales. A. aphidimyza, O. insidiosus, chrysopids, and syrphids (Diptera) had the greatest degree of density dependence on aphid populations, and spiders showed inverse density dependence. Exclusion of predators with both cages and insecticides produced significantly higher aphid populations. Because of high abundance, good synchrony with aphid populations, and high impact per individual, H. axyridis adults were the most important spirea aphid predator on apple.     

Chemical and Fishery Responses to Mitigative Liming of an Acidic Stream, Dogway Fork, West Virginia

Limestone neutralization of the acidic water of Dog-way Fork in West Virginia resulted in significant improvements in both water quality and fish populations. Pretreatment water chemistry showed the stream to be highly acidified by acid precipitation, with pH under 5.0 and high aluminum concentrations. During treatment, the goals for the target area of pH 6.5 and acid-neutralizing capacity of 50 μmeq/L were met for 75.8% and 67% of the time, respectively. A pH 6.0 or above was maintained over 93% of the time. Monomeric aluminum concentrations were reduced significantly, and calcium to hydrogen ionic ratios were over 10 in the target area. Prior to treatment, no resident fish population was found in Dogway Fork. During five years of treatment, conditions were favorable for fish reproduction and survival. Eight fish species inhabited the stream, six were reproducing there, and a fishable brook trout population was established.     

A comparison of wetland characteristics between Agricultural Conservation Easement Program and public lands wetlands in West Virginia,USA

In West Virginia, USA, there are 24 conservation easement program wetlands enrolled in the Agricultural Conservation Easement Program (ACEP). These wetlands are located on private agricultural land and are passively managed. Due to their location within fragmented agricultural areas, wetlands enrolled in ACEP in West Virginia have the potential to add wetland ecosystem services in areas that are lacking these features. We evaluated ACEP wetlands compared to reference wetlands on public land in West Virginia by using surrounding land cover, vegetative cover, and wetland features and stressors such as the presence or absence of erosion, upland inclusion, algal mats, and evidence of impacts from the surrounding landscape as surrogate measurements of wetland function on 13 ACEP wetlands and 10 reference wetlands. ACEP wetlands had higher percentages of tree coverage and a higher proportion of agricultural land in the areas immediately surrounding the wetland. Reference wetlands had higher percent coverage of emergent vegetation and had a higher proportion of forest in the immediate landscape. Our findings suggest that ACEP wetlands provide valuable early successional and forested wetland cover in a state that is largely forested. Because of this, it is important to maintain and even expand ACEP in West Virginia to continue providing a valuable source of early successional wetland habitat.     

A respiratory alert model for the Shenandoah Valley, Virginia, USA

Respiratory morbidity (particularly COPD and asthma) can be influenced by short-term weather fluctuations that affect air quality and lung function. We developed a model to evaluate meteorological conditions associated with respiratory hospital admissions in the Shenandoah Valley of Virginia, USA. We generated ensembles of classification trees based on six years of respiratory-related hospital admissions (64,620 cases) and a suite of 83 potential environmental predictor variables. As our goal was to identify short-term weather linkages to high admission periods, the dependent variable was formulated as a binary classification of five-day moving average respiratory admission departures from the seasonal mean value. Accounting for seasonality removed the long-term apparent inverse relationship between temperature and admissions. We generated eight total models specific to the northern and southern portions of the valley for each season. All eight models demonstrate predictive skill (mean odds ratio = 3.635) when evaluated using a randomization procedure. The predictor variables selected by the ensembling algorithm vary across models, and both meteorological and air quality variables are included. In general, the models indicate complex linkages between respiratory health and environmental conditions that may be difficult to identify using more traditional approaches.     

Rhacophyton from the Upper Devonian of West Virginia

A new species of Rhacophyton, R. ceratangium , is described from Upper Devonian rocks of West Virginia, U.S.A.; this is synonymous with R. incertum (Dawson) Krausel and Weyland but reasons are cited to indicate that the latter species name is not appropriate.
The collections include: stems up to 2 cm in diameter bearing bipinnate, non-laminate vegetative fronds; abundant well preserved fertile fronds that show clearly the distinctive morphology of their sterile and fertile pinnae; fragments of axes with woody tissues petrified.
The sporangia are particularly distinctive with their long slender tip; they dehisced longitudinally and contained several hundred spores; all available evidence indicates that the plant was homosporous. All petrified axes have a slender bar-shaped strand of primary wood swollen at either end and surrounded by strongly developed secondary wood consisting of scalariform tracheids and rays.
R. ceratangium is closely related to the Belgian R. zygopteroides Leelercq. A comparison with other Devonian and Carboniferous pteridophytes suggests that Rhacophyton is probably a primitive member of the Progymnospermopsida or immediately ancestral to that group.     

An Investigation of Total Mercury in Sediments and Interstitial Water in the North Fork Holston River below Saltville,Virginia, USA

The North Fork Holston River (NFHR) is historically renowned for having one of the most diversity rich unionid populations (Unionidae) worldwide; however, in recent decades, drastic reductions in mussel diversity, abundance, and recruitment have been documented. Unionid declines have been blamed on anthropogenic influences, specifically mercury-contaminated wastewater from a now closed chlorine-alkali plant in Saltville, VA. The objective of this research was to evaluate total mercury (Hg) contamination of sediments and interstitial waters in the NFHR beginning below Saltville and downstream for approximately 50 river miles. Mercury contaminated sediments and interstitial water were found downstream of the closed plant with the highest sediment concentration of 2.82 mg/kg dry weight total Hg found at river mile (rm) 80 and the highest interstitial water value at rm 30.4 with 2.1 μg/l. After 60-d in situ testing, total Hg concentrations in Asian clam (Corbicula fluminea) tissues were found to range from 0.016 to 0.13 mg/kg, while resident clams had Hg concentrations of 0.094 and 0.11 mg/kg wet weight. Although chronic toxicity was not observed, based on Corbicula growth and survival tests, nor in testing with cladocerans, mercury contamination is still a persistent problem at sites in the NFHR below the closed plant with negative correlations between mean clam growth and sediment Hg concentrations.     

Dendrochronological dating of the Graves Mill grist mill,Madison County,Virginia, USA

Historical dendroarchaeology uses annual tree-ring widths varied by climate to crossdate structures of potential historical significance. In the Southeastern U.S. Piedmont specifically, crossdating these structures can lead to a broader historical interpretation during and after the colonial era. Our study used historical dendroarchaeology to date the Graves Mill grist mill located in Madison County along the western edge of the Virginia Piedmont. The mill and mill site reflect a regional trend in eighteenth century land use as agriculture transitioned from tobacco to wheat production in response to demand from international markets, as well as the adverse impact of tobacco cultivation on piedmont soils. Mills in this region have also been subject to flooding events from storms, with events recorded in the colonial era to a recent record flood in 1995, as well as re-building with changes in mill technologies through time. In an effort to date this structure as part of its restoration, and to verify the repeatability of this dating, ring widths from six timbers from the upper stories were analyzed independently at tree-ring laboratories at the University of Tennessee, Knoxville and Rider University. Both laboratories identified an 1816 cutting date for these samples, supporting documentary evidence that the mill likely underwent modifications over time after it was initially constructed in the eighteenth century. The consistent crossdating of these samples highlights the usefulness of dendrochronology as a research tool in the Southeastern U.S. for interpreting historical structures and their surrounding historical context.     

The effects of nutrient addition and pH manipulation in bag experiments on the phytoplankton of a small acidic lake in West Virginia,USA

In situ bag experiments were performed during summer and autumn in a small acidic lake, Tibbs Run Lake, West Virginia, USA. The objective was to evaluate phytoplankton responses to pH manipulation and nutrient addition. Increasing the pH from below 4.5 to over 6.3 resulted in great declines in phytoplankton biovolume. There was also a succession from dinoflagellates (Peridinium inconspicuum to small chlorophytes. The trend was more rapid where phosphorus (P) additions were made along with pH enhancement. During summer, P limitation was indicated, while nitrogen (N) appeared to limit production in autumn. In both seasons, nutrient additions greatly altered the phytoplankton composition in high pH treatments, but had no discernable effects at (the natural) low pH. A low pH, P addition treatment in autumn was the single exception. When N was subsequently added, phytoplankton composition changed dramatically, probably because the proceeding P additions caused severe secondary N-limitation. In general, however, the results supported the view that phytoplankton compositional responses to nutrient additions are suppressed in low pH, relative to high pH lake water.