Growth Rate and Biomass Responses of Periphytic Algae to Phosphorus Enrichment in Experimental Flumes, Athabasca River, Seasonal Variation, 1993 and 1994


Book Description

Presents results of an experiment conducted in artificial streams (flumes) in which the growth of periphyton (algae) was studied in relation to phosphorus concentrations in the water. The goal of the study was to determine whether periphyton growth in the Athabasca River was phosphorus limited and whether the degree of phosphorus limitation varied seasonally. The experimental flumes were located on site, adjacent to the Athabasca River at Hinton. The experiment was designed to test periphyton growth and biomass response to a gradient of phosphorus additions during fall and early spring. Periphyton response was compared for phosphorus additions of zero (control), 1, 10, and 25 micrograms per litre of phosphorus (spring and fall 1994) or zero, 0.1, 0.2, 1, 5, 10, 25, and 50 micrograms per litre of phosphorus (fall 1993). Results include relative specific growth rates as indicated by measuring the build-up of chlorophyll a, the level at which growth rate saturation occurred, and phosphorus concentrations required to reach maximum biomass levels.




Growth Rate and Biomass Responses of Periphytic Algae to Phosphorus Enrichment in Experimental Flumes, Athabasca River, April and May, 1994


Book Description

Presents results of an experiment conducted in artificial streams (flumes) in which the growth of periphyton (algae) was studied in relation to phosphorus concentrations in the water. The goal of the study was to determine whether periphyton growth in the Athabasca River was phosphorus limited and whether the degree of phosphorus limitation varied from a similar study conducted in fall 1993. The experimental flumes were located on site, adjacent to the Athabasca River at Hinton. The four-week experiment consisted of four treatments: a control of zero phosphorus addition and three experimental levels of 1, 10, and 25 micrograms per litre of phosphorus. Results include relative specific growth rates as indicated by measuring the build-up of chlorophyll a, the level at which growth rate saturation occurred, and phosphorus concentrations required to reach maximum biomass levels in spring.




Nutrient Enrichment in the Peace, Athabasca and Slave Rivers


Book Description

Synthesises results from research and monitoring studies undertaken to characterise nutrient loading from all point and diffuse sources in northern Alberta river basins. Also evaluates the impacts of nutrient loading on river chemistry, assesses the response of riverine biota to nutrient loading from pulp mill and municipal effluents, quantifies nutrient responses of benthic biota, and investigates interactions between nutrients and contaminants in pulp mill effluents on food webs. The findings are used to assess the state of aquatic ecosystem health and to develop scientific and management recommendations for the northern river basins.







Northern River Basins Study


Book Description

Report to the federal ministers of Environment and Indian & Northern Affairs, Alberta's Minister of Environmental Protection, and NWT's Minister of Renewable Resources. Summarises the main scientific findings of the Northern River Basins Study, which was established to examine the relationship between industrial, municipal, agricultural, and other development and the Peace, Athabasca, and Slave River basins. Reviews the characteristics of the northern river basins and their peoples, the organisation of the Study, and major findings in the areas of environmental overview, use of aquatic resources, traditional knowledge, flow regulation, fish distribution and habitat, nutrients, dissolved oxygen, contaminants, drinking water, ecosystem health, modelling, human health, and cumulative effects. Recommendations by the Study Board, First Nations, and scientific advisors regarding such issues as basin management, monitoring, research, public participation, and a successor organisation are then presented. Also includes a summary of opinions, suggestions, and recommendations expressed at 17 community workshops held throughout the northern river basins area.




Impacts of Contaminants and Nutrients in Bleached Kraft Mill Effluent on Benthic Insect and Periphyton Communities


Book Description

Discusses results from artificial stream experiments in relation to the effects of effluent stressors and nutrient enrichment on benthic algal and invertebrate communities; also compares results from autumn 1993 and 1994 to document between-year variability in the relationships between effluent additions, and effects on primary and secondary producers. Results from spring 1994 are contrasted with those from autumn 1993 and 1994 to assess the importance of seasonal changes in moderating the nutrient-contaminant effects on benthic food web interactions. The artificial stream experiments were designed to decouple the effects on the riverine food web of the potentially confounding effects of nutrients and contaminants within effluent. By comparing the effects of nutrient and effluent treatments on different trophic components of the food web, the study was able to provide a mechanistic understanding of the stimulatory and/or inhihbitory effects of pulp mill effluents on the benthic food webs of the Athabasca River.







Growth Rate and Biomass Responses of Periphytic Algae to Nutrient Enrichment of Stable and Unstable Substrata, Athabasca River


Book Description

This report presents the results of an experiment conducted in artificial streams in which the growth of benthic algae was studied in relation to the phosphorus and nitrogen concentrations in the water. The goal of the study was to determine whether benthic algal biomass in the upper Athabasca River is limited by the availability of phosphorus or nitrogen. The results include the taxonomic, growth, and biomass responses by periphytic algae to phosphate additions of up to 50 micrograms per liter. The report also develops a model describing change in relative peak biomass with phosphorus addition, using data from the Athabasca experiments. Comparisons are made with a similarly derived model using results from experiments on the South Thompson River.







Before and After an Oil Spill


Book Description

Because this industrial activity posed such a threat to the fragile ecosystem, biologists had been monitoring the region's water, soil, vegetation, and wildlife for some time before the oil spill. Thus, we have before-and-after data about the habitat - the only oil spill anywhere for which this is true.