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Ashby Pond in the City of Fairfax, Virginia was retrofitted to treat runoff from 54.7 hectares of urban land of mixed use. The pond discharges into Accotink Creek, a highly urbanized tributary of the Potomac River and Chesapeake Bay that is listed on the State of Virginia 303(d) list for multiple impairments. The entire multi-state Chesapeake Bay Watershed is subject to Total Maximum Daily Load (TMDL) restrictions on sediment, phosphorus and nitrogen. Virginia and local municipalities assign pollutant reduction credits to retention ponds that meet certain design requirements. However, to actually meet existing and future water quality goals set by TMDLs, it must be proven that such ponds truly provide the water quality benefits for which they have been credited. The inflow and outflow water quality of Ashby Pond was examined over 7 months from fall 2012 to spring 2013. During that period, the pond provided statistically significant reductions of phosphorus, nitrogen and suspended sediment, but not organic carbon or oxygen demand. Ashby Pond had non-significant export of sodium, chloride and calcium. The pond underperformed when compared to state reduction credits for phosphorus load and concentration, but met and exceeded the credits for nitrogen load and concentration, respectively. The pond was under-sized compared to state design standards, and some underperformance should be expected. / Master of Science

The foraminiferal population of Yaquina Bay was investigated to attempt a correlation of seasonal changes in the hydrography with observed changes in the faunal distribution patterns. The results are based on data from two spatial surveys conducted in July 1966, and late February and March, 1967. The hydrography of Yaquina Bay undergoes seasonal changes closely paralleling the seasonal precipitation pattern. Except for short-term variations, the estuarine system is partly-mixed during the period of maximum river discharge (November to May) and wellmixed from June through October. Coastal upwelling (high salinity, low temperature) has a marked influence on the hydrography of the lower bay during the summer; maximum salinities and temperatures prevail in the upper reaches of the estuary during late summer and fall. Species associations were determined by the Fager-McConnaughey correlation coefficient method; similar assemblages were found for both summer and winter surveys. A marine biofacies fauna, dominated by Elphidium microgranulosum and E. frigidum, occupies the main estuary channel for about five miles upstream. The distributional patterns of the living fauna show evidence of a stronger marine influence during the summer, corresponding to a similar pattern in the hydrography. In the lower bay, the Elphidium fauna is displaced laterally by an assemblage characterized by Trochammina charlottensis and Elphidium incertum in the middle intertidal zone. This assemblages in turn gives way to an Ammobaculites exiguus -Miliammina fusca fauna in the upper intertidal area. The Elphidium assemblage gives way to a Miliammina fauna in the upstream direction. Trochammina inflata, T. macrescens, Miliammina fusca, Jadamminina polystoma, Haplophragmoides sp., H. hancocki and Siphotrochammina lobata are the principal species found in the marine marsh. Zones of environmental similarity were defined by the index of affinity association analysis. Living and total faunas of both winter and summer surveys were considered separately; several sample groups were defined in each case. Index of affinity data can also be used to provide an index of the marine influence on the foraminiferal population of the estuary. Species diversity or the average number of species/sample, ranges from 22 in the marine biofacies zone to six on the lower bay tideflats. An intermediate value (l0/sample)was found for the marine marsh. Highest standing crops were found in the marshes (summer) and on the tideflats adjacent to the lower bay channel, averaging 40 and 42/cm² respectively. Lowest values (1 to 2 cm²) were found in the middle to upper intertidal areas of the lower bay during the summer. The distribution of the total fauna is quite similar to that of the living population. Highest average values (175/cm³) are again found in the marine marsh and in the marine biofacies zone (70 to 80/cm³). Lowest values occur on the lower bay intertidal areas (3 to 9/cm³). In general, the percentage representation of agglutinated species in the total fauna increases with distance upstream in the channel and with distance laterally from the channel axis. Faunas of some marsh stations are composed entirely of agglutinated species. The percentage of calcareous hyaline species shows an inverse relation to that of the agglutinated fauna, increasing in importance with approach to marine conditions. Porcelaneous and planktonic species are generally minor constituents in the total fauna and are restricted to the marine biofacies as it is developed in the estuary. Foraminifer-ostracod ratios are extremely variable in the environments sampled in Yaquina Bay. Smooth-valved species are characteristic of the marine marsh and inner bay environments; valve ornamentation tends to increase with approach to marine conditions. Thecamoebians are present in low numbers throughout the estuary. In general however, the number of species and population size increases in the upstream direction. / Graduation date: 1968

Graduation date: 1964

The benthic microalgae of sediments of the two tidal flats in Yaquina Bay, Oregon were investigated to determine the environmental factors limiting the abundance and the horizontal and vertical distribution of these organisms. The Southbeach tidal flat which is under the marine realm of deposition consists of fine to medium grained sand. The Sally's Bend tidal flat is under the fluviatile realm of deposition and consists of silt. Measurements were made of interstitial temperatures, movements of sand, turbidity, pH, salinity, depth of light penetration through the sediments, and the water content of the substrate. Samples of the benthic microalgal community were collected by using a piston corer. Sections of the cores were used for estimating the biomass: (1) by making direct counts of live microalgae, (2) by estimating chlorophyll a concentration and (3) by measuring ash-free dry weight. The greatest biomass of microalgae was found to be in cores from the lower intertidal zone while cores from the upper intertidal zone had the lowest biomass. This distribution probably results from the greater fluctuations in temperature, salinity, water content, and oxygen content, which are more variable in the upper intertidal zone. The greater biomass in cores from the lower intertidal zone may be the result of less fluctuation in environmental factors as well as the fact that this area is exposed to nutrient-laden water for longer periods of time than the upper intertidal zone. The greatest biomass of microalgae was found in the upper centimeter of cores collected at all levels of the intertidal zone, because light can penetrate no more than a few millimeters through sediment. Occurrence of algae below the photic zone is thought to result from vertical migration, sedimentation, or the activity of burrowing animals. It was found that the Southbeach tidal flat had a significantly greater biomass than Sally's Bend at all intertidal levels and in the various layers of the cores. This was attributed to differences in environmental conditions peculiar to each tidal flat which is the result of the hydrography of the bay. Estimates of the rates of potential gross production were made using a Gilson Differential Respirometer. The community from the Southbeach tidal flat had a greater potential gross rate of production than the Sally's Bend community. This was partially the result of high rates of bacterial respiration in cores from the Sally's Bend tidal flat. This tidal flat had significantly greater amounts of organic matter than Southbeach and the abundance of bacteria in sediment is related to the amount of organic matter. Measurements of the concentrations of chlorophyll a were corrected for the percentage of pheophytin present. Significantly greater amounts of pheophytin were found in cores from the Sally's Bend tidal flat which probably resulted from the large amounts of allochthonous detrital chlorophyll deposited in these sediments. The microflora consisted almost exclusively of diatoms. One hundred and fifty-four species and varieties were identified. Most of the species found in the lower intertidal zone were found in the mid and upper intertidal zones as well. Many of the species identified have never been reported from Oregon prior to this investigation. / Graduation date: 1969

Latent and sensible heat fluxes at the surface of Baffin Bay are calculated throughout the year using, in addition to the essential meteorological data and surface temperatures, values of the ice cover corresponding to three different periods of years, ranging from 1919 to 1965. [...]

Food use and nutrient intake were studied with Cree women of Wemindji and Eastmain, Quebec. Twenty-four hour recalls and food frequency questionnaires were used among three age groups of women and in two seasons. Age had an effect on the mean amount of traditional food consumed (p $<$ 0.0001). Species and amounts of traditional food consumed varied by season. Ninety-four percent of women exceeded 2/3 of the recommended nutrient intake (RNI) for protein and 80% exceeded 2/3 of the RNI for iron, despite lower than recommended reported energy intakes. Calcium intakes of less than 1/2 the RNI were reported by 44% of women. Mean total fat intake reported by young and middle adults was greater than 30% of total energy. Qualitative inquiry into changing food use revealed that most women agree that traditional food use has declined for a variety of reasons, and that community residents should use more traditional food.

This study examines modern relationships among salt marsh plant species and their pollen in three salt marshes located on the northwest coast of the Bay of Fundy, New Brunswick. Linear regression analysis of pollen in 35 surface sediment samples and vegetation cover on small (<15 m) and broad (>15 m) scales show that, with the exception of Poaceae and Cheno Am, pollen corresponds well with fine-scale patterns of salt marsh vegetation. Scatter diagrams of paired pollen and cover data illustrate that cover of Triglochin is over-represented by its pollen, Glaux is under-represented, and Poaceae, Cheno Am, and Plantago are inconsistent. Tidal mixing and differential inputs from local, regional, and extra-regional sources with elevation limit the establishment of plant-pollen relationships for Cheno Am and Poaceae but not for other taxa. Comparison of 35 modern analogs from five vegetation zones using squared chord distance show that zones are distinct such that the marsh-terrestrial interface can be tracked with the greatest degree of certainty in a salt marsh paleo-ecological record and other marsh zones can be tracked when a conservative threshold of dissimilarity is used.

Graduation date: 1987

Typescript (photocopy) / Bibliography: leaves 163-177. / Microfiche. / xi, 177 leaves, bound ill., maps 29 cm