Robert G. Verb

Comparison of benthic diatom assemblages from streams draining abandoned and reclaimed coal mines and nonimpacted sites

We examined whether there was a particular group of diatoms specific to acid mine drainage (AMD) sites and/or reclaimed sites in streams in a coal-mining region of southeastern Ohio. Streams were initially placed into 5 categories: 1) stream receiving AMD from an unreclaimed site, 2) stream receiving drainage from a site reclaimed prior to a 1972 regulation, 3) stream receiving drainage from a site reclaimed between 1972 and 1982 under Ohio Revised Code (ORC) 1513, 4) stream receiving drainage from site reclaimed after 1982 under the Surface Mining Control and Reclamation Act (SMCRA), and 5) stream not impacted by AMD. The diatom flora from riffles in each system and environmental parameters (pH, conductance, metal concentrations [Al, Fe, Mn], current velocity, width, and depth) were examined to assess the recovery of reclamation sites from mining. Canonical correspondence analyses separated heavily impacted AMD streams from other sites. Total alkalinity and pH were highly correlated to the 1st axis, and SO4, average depth, and temperature were influential in additional axes. Discriminant analyses of the diatom and environmental data sets were successful in assigning samples into 1 of the a priori stream categories (85% and 81.8% accuracy, respectively). AMD streams were characterized by a dominant flora of Eunotia exigua and Frustulia rhomboides. Streams that fluctuated between acidic and circumneutral pH (termed oscillating) had greater abundances of Brachysira vitrea than other study streams. Streams of intermediate water quality (i.e., reclaimed sites) were dominated by Achnanthidium minutissimum. There was a predictable relationship between post-reclamation stream water quality and diatom assemblages, which may prove useful in assessment and management of reclamation efforts.

Macroalgal communities from an acid mine drainage impacted watershed

Twenty-eight streams were sampled seasonally and a subset of 10 streams was sampled monthly for one year throughout the Hocking River drainage basin, Ohio, USA. Streams ranged from those receiving acid mine drainage (AMD), to reclaimed sites, to those never receiving mine wastes. Physical and chemical parameters were measured and macroalgal taxa were collected with estimations of percent cover. Canonical correspondence analysis showed AMD and seasonal parameters to be influential in grouping streams and macroalgal communities. The macroalgal composition was only useful in distinguishing between heavily impacted AMD streams and all others. We were unable to utilize the macroalgal community to detect differences among reclaimed sites and clean streams. This result was most likely due to the spatially heterogeneous occurrence of many macroalgal taxa. Two taxa, Klebsormidium rivulare and Microspora tumidula, did appear to be useful assessors of intense AMD impact. A total of 40 infrageneric taxa were recorded with the greatest species richness occurring in the spring (27 taxa). Chlorophytes were the dominant group throughout the watershed with 19 species. Percent macroalgal cover of stream reaches varied throughout the year within a single stream and among lotic systems. Our results showed that numerous taxa were overlooked in the seasonal versus monthly sampling, but that sampling more streams on a less frequent basis compensated to provide a complete listing of taxa for the watershed.

Algal colonization of submerged carcasses in a mid-order woodland stream.

One of the primary goals of forensic pathology is the determination of time of death. In aquatic systems, one method to do this is to analyze the colonization of a corpse by algae. Algal communities typically follow a serial colonization pattern, therefore the taxa present at any given time may provide clues about postmortem submersion time. This study was undertaken to examine the algal colonization on rat carcasses in a medium-order woodland stream. Two habitats were studied: a low flow pool and a high flow riffle, with rats being removed from each site every 3 to 6 days over 31 days. The diversity of colonizing taxa increased at both sites as the study progressed, and after 17 days similar taxa were present (Sorensens similarity index >60%) in each site. Some taxa, such as desmids (Chlorophyta), tended to increase in diversity throughout the study, making them possible indicators of submersion time. Diatoms were the most abundant taxa found in each site and accounted for 63 of the 92 total taxa identified. Due to their ubiquitous presence in nearly all streams, we suggest that diatoms may be the key organisms for the study of postmortem submersion in lotic systems.

An Investigation of the Cryptobiotic Community from Sandstone Cliffs in Southeast Ohio

Because of harsh environmental conditions, cliff walls tend to have depauparate vascular plant floras. However, the resistance to desiccation and low light requirements of algae and cyanobacteria make them integral components of cliff walls. In addition, protozoa may be present within moist microhabitats. To document part of the cryptobiotic flora of these habitats, nine cliffs were sampled in the Hocking Hills, Ohio, vicinity over a 3‐mo period in the spring of 1999. A total of 140 infrageneric algal and 25 nonphotosynthetic protozoan taxa were recorded. The algal flora was dominated by bacillariophytes (80 taxa), with cyanobacteria (43), chlorophytes (12), euglenophytes (4), and xanthophytes (1) comprising the remainder of observed taxa. The majority of cyanobacterial taxa were chroococcalian forms that were collected at all nine sites. In addition, 15 nonnitrogen‐fixing filamentous forms were observed but tended to be less abundant. Protozoan taxa were comprised of ciliates (18 taxa), heliozoans (4), and rhizopods (3). All major groups of taxa exhibited the greatest abundance and diversity during March and decreased throughout April and May. Environmental parameters (light, temperature, humidity, moisture, and aspect) were measured and combined with species data for cluster (unweighted pair group mean average clustering) and canonical correspondence analysis (CCA). Cluster analysis showed little geographical grouping of sites, but the sites appeared to be clustered based on moisture level. The CCA showed four significant ( \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage[OT2,OT1]{fontenc} \newcommand\cyr{ \renewcommand\rmdefault{wncyr} \renewcommand\sfdefault{wncyss} \renewcommand\encodingdefault{OT2} \normalfont \selectfont} \DeclareTextFontCommand{\textcyr}{\cyr} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} \landscape

A Two-year Survey of the Algal Community in a Woodland Stream from Southeastern Ohio

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New Records of Vaucheria Species (Xanthophyceae) with Associated Proales Werneckii (Rotifera) from North America

\end{document} ) axes, primarily related to aspect, which accounted for 22.47% of the total variance. This axis was negatively correlated with light and moisture. Mesic cliffs tended to have a greater diversity of taxa than xeric ones, and open sites more than shaded sites.

Spatial Heterogeneity of the Bacterial Community in a Newly Rehabilitated Wetland

We investigated the response of an algal assemblage to different vegetative substrates in controlled vernal mesocosms. Litter was collected from four vascular plant communities (Deciduous Forest, Macrophyte, Old Field and Pinus stands) and the litter was used to line the benthos of the vernal mesocosms. The development and response of the algal assemblage in treatment and control mesocosms was tracked biweekly for a period of 56 days. A repeated-measure MANOVA and Bonferroni (Dunn) post-hoc test indicated that the Pinus treatment produced a significantly greater biomass than all other treatments. The Pinus treatment mesocosms had acidic (4.5–4.7) water when sampled on day 42, which continued until the completion of the study. The greatest levels of species richness and diversity were recorded from the Deciduous Forest and Old Field treatments. Algal assemblage analyses indicated that there was much overlap in community structure between various litter treatments and algae alone (no litter). Most of the vernal mesocosm treatments were dominated by the filamentous chlorophytes Mougeotia, Oedogonium and Ulothrix. These results suggest that, in this study, the vegetative litter of vernal mesocosms (with the exception of Pinus) exhibits limited independent influence on the developmental trajectories of algal communities.

Influences of a Tsuga canadensis (L.) Carriere (Eastern Hemlock) Riparian Habitat on a Lotic Benthic Community

Abstract A survey of the algal flora for a minimally polluted stream in southeastern Ohio was conducted over a two-year period (17 sampling dates) as part of an all-taxa biotic survey. Four algal categories were sampled: macroalgae (readily visible with the naked eye), microalgae (associated with macroalgae), erosional periphyton (microalgae from riffles), and depositional periphyton (microalgae from pools). A total of 217 infrageneric taxa were collected. There were 25 cyanobacteria, 74 chlorophytes, 6 chrysophytes, 3 cryptophytes, 86 diatoms, 4 dinophytes, 12 euglenophytes, 1 raphidophyte, 3 rhodophytes, and 3 tribophytes. A seasonal trend was observed in species richness; fall had the most taxa (136), followed by winter (107), summer (100), and spring (82). Approximately half of the taxa occurred in samples from more than one season, but only 15% were present year-round. Overall, species richness was not correlated to any stream parameter. However, diatom species richness was positively correlated to pH, and both diatom and soft-bodied algal richness were negatively affected by nutrient loading. For the soft-bodied algae, the microalgae category was the most species-rich followed by the depositional periphyton, erosional periphyton, and macroalgae. For the diatoms, the depositional periphyton had higher species richness than the erosional periphyton. Five diatom and 17 soft-bodied algal taxa previously unreported from the Unglaciated Western Alleghany Plateau were identified from this stream reach. This study highlights the need for multiple samplings in different seasons to capture the total species richness, since only a small fraction of the taxa were collected year-round and one third of the diatoms collected were rare.