A Comparison of Benthic Oligochaete Populations in Acid and Neutral Lentic Environments in Southeastern Ohio

Author Institution: Department of Zoology and Microbiology, Ohio UniversityORCIARI, ROBERT D. AND WILLIAM D. HAMMON. A comparison of benthic oligochaete populations in acid and neutral lentic environments in Southeastern Ohio. Ohio J. Sci., 75(1): 44, 1975

Adaptation of Cambarus bartonii cavatus (Hay) (Decapoda: Cambaridae) to Acid Mine-Polluted Waters

Author Institution: Department of Zoological and Biomedical Sciences, Ohio UniversityJuvenile crayfish [Cambarus bartonii cavatus] were taken from two nearby sites on Big Four Creek, Vinton County, OH. Water from upstream (UpS) and downstream (DnS) sites had total conductivities of 250 |iS and 600 \xS (|J,S = jimho/cm2) at 25° C. Non-carbonate conductivity was largely made up of sulfuric acid and heavy metals. Carbonates represented 40% of the conductivity at UpS but were absent from DnS. With only 100 (0.S of carbonate buffering capacity, water from UpS had little ability to neutralize acidic input, and this was easily overcome. Tests in seven solutions ranging between 250 (iS and 5000 \iS showed that: 1) mortality of crayfish was effected by the conductivity of test solutions, 2) DnS crayfish survived longer than UpS crayfish in all test conditions except the clean UpS water, and 3) there was no interaction term between source area and strength of conductivity on longevity. Attempts to acclimate crayfishes to higher levels of mine acid over short time periods were unsuccessful. Crayfish mortality under low acid conditions was not increased by addition of iron precipitate, though deaths were associated with ecdysis at intermediate and higher concentrations of mine acid. If DnS, but not UpS, crayfishes of this subspecies have acclimatized to intermediate concentrations of mine acid, then we infer a regime of semi-isolated reproduction over a short distance of streambed. Such an adaptation might have evolved following long—term exposure to low level, naturally—occurring acid seepage from coal outcrops, with success depending on the pre-adaptation of this subspecies to life in waters that are naturally low in carbonate buffering capacity

Acid Mine Pollution : Effects on Survival, Reproduction and Aging of Stream Bottom Microinvertebrates

This study was supported by the Office of Water Research and Technology U.S, Department of the Interior under Project A-051-OHIO(print) 74 leaves in various foliations : ill. ; 28 cm

Gastrotricha: A Marine Sister for a Freshwater Puzzle

Background: Within an evolutionary framework of Gastrotricha Marinellina flagellata and Redudasys fornerise bear special interest, as they are the only Macrodasyida that inhabit freshwater ecosystems. Notwithstanding, these rare animals are poorly known; found only once (Austria and Brazil), they are currently systematised as incertae sedis. Here we report on the rediscovery of Redudasys fornerise, provide an account on morphological novelties and present a hypothesis on its phylogenetic relationship based on molecular data. Methodology/Principal Findings: Specimens were surveyed using DIC microscopy and SEM, and used to obtain the 18 S rRNA gene sequence; molecular data was analyzed cladistically in conjunction with data from 42 additional species belonging to the near complete Macrodasyida taxonomic spectrum. Morphological analysis, while providing new information on taxonomically relevant traits (adhesive tubes, protonephridia and sensorial bristles), failed to detect elements of the male system, thus stressing the parthenogenetic nature of the Brazilian species. Phylogenetic analysis, carried out with ML, MP and Bayesian approaches, yielded topologies with strong nodal support and highly congruent with each other. Among the supported groups is the previously undocumented clade showing the alliance between Redudasys fornerise and Dactylopodola agadasys; other strongly sustained clades include the densely sampled families Thaumastodermatidae and Turbanellidae and most genera. Conclusions/Significance: A reconsideration of the morphological traits of Dactylopodola agadasys in light of the new information on Redudasys fornerise makes the alliance between these two taxa very likely. As a result, we create Anandrodasys gen. nov. to contain members of the previously described D. agadasys and erect Redudasyidae fam. nov. to reflect this novel relationship between Anandrodasys and Redudasys. From an ecological perspective, the derived position of Redudasys, which is deeply nested within the Macrodasyida clade, unequivocally demonstrates that invasion of freshwater by gastrotrichs has taken place at least twice, in contrast with the single event hypothesis recently put forward

Läst genom kameralinsen : studier i filmiserad svensk roman

Vad har hänt med romanen i "filmens tidsålder"? Hur har den påverkats under filmmediet? I denna bok undersöker Ohlsson romaner av sex svenska författare – Hjalmar Bergman, Stig Dagerman, Gösta Gustaf-Janson, Per Gunnar Evander, Vilgot Sjöman och Stig Larsson – som alla har erfarenhet av filmarbete. De studerade romanerna är "filmiserade" i olika avseenden: de kan handla om filminspelning och biobesök, eller vara berättade på ett sådant sätt att läsaren kan associera till filmens berättarteknik

Phylogenetic relationships of 43 Gastrotricha Macrodasyida inferred from Bayesian analysis of 18 S rDNA.

<p>The outgroup is represented by <i>Xenotrichula intermedia</i> (Chaetonotida, Xenotrichulidae). Number at nodes represents posterior probabilities.</p