Thesis (M. Sc.)--University of Canterbury, 2007. / Typescript (photocopy). "June 2007." Includes bibliographical references (leaves 83-94). Also available via the World Wide Web.

Thesis (doctoral)--Lunds universitet, 1983. / Includes bibliographical references.

No description available.

Recent evidence strongly suggests that aluminum toxicity is important in determining the structural and functional characteristics of freshwater communities affected by acid precipitation. To determine the effect dissolved aluminum has on lotic invertebrates previously unexposed to anthropogenic acidification, experiments were carried out in a second-order headwater stream 50 km east of Vancouver, British Columbia during August 1982. In three separate experiments, HC1 and/or A1C1₃ were added to Mayfly Creek during daylight hours, increasing acidity from pH 6.9 - 7.0 to pH 5.8 - 6.0 and total aluminum from < 0.1 mg/L to > 1.0 mg/L. Biological response was monitored by sampling invertebrate drift with 86 Mm nets. Relative to an unmanipulated, upstream control site, drift density doubled in response to added H⁺ alone (pH 5.9). When Al₃⁺ was added (pH 5.9) drift density increased fourfold. Following 48 h continuous dosing with HC1 (pH 5.9) there was an even greater response to added Al₃⁺. Ephemeroptera were able to detect dissolved aluminum and responded almost immediately (within 45 min). Similarly, Trichoptera and Chironomidae detected increased H⁺ concentrations and responded immediately. Response to augmented Al₃⁺ by Trichoptera, Hydracarina, and Chironomidae was delayed 6 h. However, pre-exposing animals to 48 h HC1 resulted in enhanced aluminum sensitivity for Chironomidae and for Simulium and Plecoptera, which had not responded within 10 h to H⁺ or Al₃⁺ alone. It is proposed that rapid increases in drift density are due to behavioral escape responses, while delayed responses are probably associated with physiological impairment. Evidence was also obtained suggesting that during early stages of morphological development Ephemeroptera and Chironomidae are more sensitive to increased Al₃⁺ and H⁺ concentrations than during later developmental stages. In laboratory experiments using artificial stream channels, Chironomidae larvae and Ephemeroptera nymphs were exposed to CI⁻ and H⁺ concentrations, equal to those during field experiments. Results showed that drift behavior in these animals is not stimulated by mildly elevated chloride concentrations. These studies demonstrate that increased dissolved aluminum concentrations intensify biological response to acidification, and confirm acid sensitivity patterns for Ephemeroptera and Chironomidae reported by others. The observed acid insensitivity of Plecoptera, simuliids, and Trichoptera also conforms to previously described patterns. Experimentally manipulating this community produced results closely resembling those obtained in similar studies for areas currently affected by acid precipitation. The major difference in results between studies is that invertebrate communities previously unexposed to acidification contain more species sensitive to mild acidification. These latter animals are particularly sensitive to the presence of elevated dissolved aluminum concentrations. / Science, Faculty of / Zoology, Department of / Graduate

Ph.D. / An investigation was made into the physical, chemical and biological conditions of the Elsburgspruit to establish the extent and quality of pollution over a period of two and a half years from January 1987 June 1989. The results obtained during the investigation can be summarised as follows. Serious faecal pollution as reflected by faecal coliforms, faecal streptococci and coliphage organisms occurs over a large stretch of the river, posing a health risk to the people using the recreational area at' Vosloosrust, downstream from the Elsburgspruit near Kathlehong. The occurrence and large numbers of coliphage organisms occurring at certain sampling localities suggest the possible presence of the pathogenic viruses Salmonella, Pseudomonas and Candida. Effluent and seepage waters from mining areas, discharged into the Elsburgspruit were found to be low in pH and high in concentrations of certain metals such as zinc, manganese and iron. Due to the large volume of this particular effluent, the effects thereof on the water quality and fauna of the streams are felt over a distance of more than seven kilometres. As a result, the recovery of the stream from pollution is severely retarded. A number of species of the numerically dominant aquatic and semi-aquatic macrophytes which occurred within the flood-plain of the Elsburgspruit, were found to be able to absorb and to accumulate substantial concentrations of the various heavy metals, directly from the water, or from adjacent moist soils. It was also found that the Spanish reed, Arundo donax, which covers a large area of the wetland region of the Elsburgspruit in its lower section, absorbed and accumulated substantial quantities of the different heavy metals from the water of the stream. A comparison was made of the extent to which metals are deposited into the sediment under both acidic and alkaline conditions...

Data were collected from natural and introduced fishes present in Ferndale Lake, a small (120 ha) sport fishing reservoir in Camp County, east Texas. Levels of pH measured in the lake during the study period ranged from 3.5 to 5.3. Monthly field surveys and experimental manipulations were designed to evaluate quantitatively the signs of stress at various biological levels. Lethal limits to low pH were quantified for largemouth bass (Micropterus salmoides) and bluegill (Lepomis macrochirus) to be pH 3.8 and 4.0,respectively. Mean blood pH (+ 1 SD) of 59 bluegill was 7.41 (j 0.16), with no significant difference (P-0.05) among groups from Ferndale Lake and Moss Lake (Cooke Co., Texas) under experimental conditions, even when severe stress was externally apparent. In a dual-trough horizontal pH gradient, bluegill behavioral avoidance was observed at pH levels below 7.0. Individual testing of 40 bluegill in pH gradient of 5.2 to 7.6 resulted in median occupation of pH 7.1,with an interquartile range of pH 6.9 to 7.3. Decreased community structure and population "well being" compared to early studies cannot be attributed entirely to recent acidic condition. Separating potential stress due to lake conditions from that due to heavy biotic predation by sport fishing in a small reservoir is difficult.

Thesis (M.Sc. (Hons))--University of Western Sydney, 2001. / "A thesis presented for the Degree of Master of Science (Honours), Centre for Electrochemical Research and Analytical Technology, School of Science, Food and Horticulture, University of Western Sydney, March 2001." Bibliography: leaves 62-67.

No description available.

Responses of phytoplankton productivity in the Red River to unbleached pulp and paper mill wastewaters were monitored using in situ ^14C incubation. Preoperational studies, conducted prior to the discharge of mill wastewaters varied seasonally, but revealed similar productivity trends when compared with postoperational studies, conducted after mill discharges began entering the Red River. Carbon assimilation rates measured downstream of mill discharge were generally greater than upstream levels in both preoperational and postoperational studies. Selected physical, chemical, and biological parameters varied seasonally, but showed similar upstream-downstream values and preoperational-postoperational values. Total Organic Carbon (TOC), Dissolved Organic Carbon (DOC), and Biochemical Oxygen Demand (BOD_5) were positively correlated with postoperational productivity rates. Apparent color was negatively correlated with productivity rates.

Southwestern Indiana has numerous lakes developed in abandoned coal mine spoils which support recreational sports fisheries. Some lakes, due to exposure to acid mine drainage from coal wastes and pyritic spoils, are unsuitable habitats for fisheries development. This study examines a publicly owned acid mine lake with an area of approximately 51 ha, following reclamation and elimination of acid producing areas in its drainage basin. Fifteen physico-chemical sample collections were made over a thirteen month period (1991-1992). Parameters sampled included pH, total acidity, iron, manganese, and aluminum. Comparisons were made to historic pre-reclamation water quality data and to established models of acid mine lake recovery. Due to the local topography and exposure to prevailing winds, the lake was generally well mixed throughout the study. Virtually no summer stratification was found, but typical winter season stratification occurred. The water column was well oxygenated throughout the study. Secchi disk transparency varied from 2.5 m to clear to lake bottom (6 m). This study found no significant change in lake water pH (2.9-3.0 to 3.0-3.2 s.u.) since reclamation activities in 1988. However, changes in total acidity and total metal concentrations had occurred since reclamation which suggested that the lake was in early recovery stages. No trends in water quality improvement were determined which could assist in planning toward the eventual establishment of a sports fishery. / Department of Biology