Ecology and Distibution of Chironomid Larvae from Carroll County, Ohio (Diptera: Chironomidae)

Author Institution: Department of Biology, The University of AkronChironomid larvae were collected from lotic and lentic sites in Carroll Co., Ohio, from October 1981 to October 1982. Over 700 larvae were mounted on glass slides for identification. A total of 80 species was found. The species collected are listed with site and date of collection. The number of species is comparable to that reported in other studies. Gut contents are listed for 49 species, most of which are detritivores. Some species probably change feeding habits depending on their age and stream flow. Approximate emergence periods are given for 10 species

Summer Phytoplankton Photosynthesis in a Northeastern Ohio Glacial Lake

Author Institution: Department of Biology, The University of AkronMCMURRAY, GREGORY AND JOHN H. OLIVE. Summer phytoplankton photosynthesis in a northeastern Ohio glacial lake. Ohio J. Sci. 75(5): 238, 1975

Effects of Diet on Seven-Day Ceriodaphnia dubia Toxicity Tests

Author Institution: Department of Biology, The University of AkronThe purpose of this study was to evaluate the effects of four diets on the results of seven-day Ceriodaphnia dubia toxicity tests. Survival and reproduction were used as indices to detect the sensitivity of this species to acute and chronic copper stress. All toxicity tests were conducted using the moderately hard reconstituted water recommended in 1989 by the U.S. Environmental Protection Agency. Diet differentially affected the acute and chronic toxicity of copper. Daphnids fed Selenastrum capricomutum (alga) showed the greatest sensitivity, followed by those fed the alga Chlamydomonas reinhardti, then by animals fed a Yeast-CerophyllT1^-Trout Food (YCTF) mixture plus Selenastrum, and finally by animals fed YCTF alone. These differences may result from the poor nutritional adequacy of Selenastrum when fed alone, the different caloric contents of the diets, the increased toxicant uptake by the organisms through ingestion of copperladen algal cells, and/or copper ions sequestered by fats and insoluble substances in YCTF. We recognize that diet is an important variable in seven-day toxicity tests, and that the selection of a diet should not be based only on its effects on long-term culturing of C. dubia, but also on its possible effects on test results

Primary Productivity-Phytoplankton Relationships, Hodgson Lake, Portage County, Ohio

Author Institution: Department of Biological Sciences, Kent State University, Kent, OhioPrimary productivity-phytoplankton relationships were studied for one year (1963-64) in Hodgson Lake, Portage County, Ohio. The lake was found to be a ''blue-greendiatom'' reservoir of moderate productivity, but containing a large phytoplankton standing crop, dominated by the cyanophycean, Oscillatoria rubescens Decandole. Average cell volumes ranged from 1.4 mm3 liter-1 in September to approximately 88.6 mm3liter-1 in June, over 80 percent of which were 0. rubescens. Diatoms, including Cyclotella sp, Fragilaria sp. Asterionella formosa Hass, and Synedra delicatissima W. Sm., usually accounted for <10 percent of the total cell volume. Photosynthesis ranged from 4-5 mgC m-2 day-1 during the winter to approximately 2600-2700 mgC m-2 day-1 in June and October, with an annual mean of 847.5 mgC m~2 day"1. Photosynthesis per unit cell volume ranged from <1ugC day-1 mm-3 during the winter to 172.8 gC day-1 mm-3 in October, averaging 10.5 ugC day-1 mm-3 annually

Diatom Communites in the Cuyahoga River (USA): Changes in Species Composition Between 1974 and 1992 Following Renovations in Wastewater Management

Author Institution: Department of Biology, The University of AkronPeriphytic diatom communities along the Cuyahoga River were analyzed for possible changes in species composition resulting from improvements in wastewater management within the river basin during the past 18 years. The results, compared to a similar study conducted in 1974, and controlled for seasonality and microhabitat effects, show an increase in total diatom species (75 to 105), especially pollutionsensitive species, and a reduction in pollution-tolerant species—all indications of improved water quality. Reductions were evident in the number and proportion of pollution-tolerant species such as Gomphonema parvulum, Melosira varians, Navicula cryptocephala, N. pelliculosa, Nitzschia communis, N.palea, and Synedra ulna. The number and proportion of pollution-sensitive species such as Achnanthes linearis, Amphora pediculus, Cocconeis pediculus, Diatoma vulgare, Navicula tripunctata, and Nitzschia dissipata increased. Despite changes in species composition, headwaters of the river, managed as a domestic water supply and Ohio Scenic River, continue to support 2-3 X more taxa than the lower river below the City of Akron. Substantial degradation of water quality in the lower river persists despite recent restoration efforts. A major source of pollution occurs upstream from the Akron Water Pollution Control facility because sample sites above and below this facility were very similar in diatom species composition, each dominated by Nitzschia amphibia (-40%), a well known saprophilic diatom associated with organically polluted water. Overflows from combined stormwater-sanitary sewers, within the Akron metropolitan area are the most probable cause of the continued suppression of diatom species diversity

Trophic Assessment iof Ten Publicly-Owned Northeastern Ohio Likes

Author Institution: Department of Biology, The University of Akron ; Northeast Ohio Areawide Coordinating AgencyTrophic assessments of 10 publicly-owned northeastern Ohio lakes including Aquilla, Baldwin, Findley, Hinckley, Hodgson (Muddy), Spencer, Lower Shaker, Upper Shaker, Virginia Kendall, and Wallace indicated that all were highly eutrophic. Criteria for these assessments were based on a Trophic State Index developed by the U.S. Environmental Protection Agency that incorporated epilimnetic levels of total phosphorus, dissolved phosphorus, inorganic nitrogen, dissolved oxygen, and chlorophyll a and Secchi disk water transparency into a single numerical index of trophic status (TIN). The most eutrophic lakes were Spencer, which had been purposely enriched to increase productivity, and the Shaker Lakes, which were enriched by storm water overflows of sanitary sewers. The least eutrophic lakes were Hodgson, Aquilla, Virginia Kendall, and Wallace reflecting relatively better watershed protection from soil erosion and domestic organic wastes