Factors influencing the seasonal changes in primary productivity of the photosynthetic bacteria of Crawford Lake, Ontario

A naturally occurring population of photosynthetic bacteria, located in the meromictic Crawford Lake, was examined during two field seasons (1979-1981). Primary production, biomass, light intensity, lake transparency, pH and bicarbonate concentration were all monitored during this period at selected time intervals. Analysis of the data indicated that (l4C) bacterial photosynthesis was potentially limited by the ambient bicarbonate concentration. Once a threshold value (of 270 mg/l) was reached a dramatic (2 to 10 fold) increase in the primary productivity of the bacteria was observed. Light intensity appeared to have very little effect on the primary productivity of the bacteria, even at times when analyses by Parkin and Brock (1980a) suggested that light intensity could be limiting (i.e., 3.0-5.0 ft. candles). Shifts in the absorption maxima at 430 nrn of the .bacteriochlorophyll spectrum suggested that changes in the species or strain composition of the photosynthetic bacteria had occurred during the summer months. It was speculated that these changes might reflect seasonal variation in the wavelength of light reaching the bacteria. Chemocline erosion did not have the same effect on the population size (biomass) of the photosynthetic bacteria in Crawford Lake (this thesis) as it did in Pink Lake (Dickman, 1979). In Crawford Lake the depth of the chemocline was lowered with no apparent loss in biomass (according to bacteriochlorophyll data). A reverse current was. proposed to explain the observation. The photosynthetic bacteria contributed a significant proportion (10-60%) of the lake1s primary productivitya Direct evidence was obtained with (14C) labelling of the photosynthetic bacteria, indica.ting that the zooplankton were grazing the photosynthetic bacteria. This indicated that some of the photosynthetic bacterial productivity was assimilated into the food chain of the lake. Therefore, it was concluded that the photosynthetic bacteria made a significant contribution to the total productivity of Crawford Lake.

Habitat selection of three rodents in a frequently burned boreal environment : productivity and habitat diversity

How does fire affect the plant and animal community of the boreal forest? This study attempted to examine the changes in plant composition and productivity, and small mammal demography brought about by fire in the northern boreal environment at Chick Lake, N.W.T. (65053fN, 128°14,W). Two 5*6 ha plots measuring 375m x 150m were selected for study during the summers of 1973 and 197^. One had been unburned for 120 years, the other was part of a fire which burned in the spring of 1969. Grids of 15m x 15m were established in each plot and meter square quadrats taken at each of the 250 grid intersections in order to determine plant composition and density. Aerial primary production was assessed by clipping and drying 80 samples of terminal new production for each species under investigation. Small mammal populations were sampled by placing a Sherman live trap at each grid intersection for ten days in every month. The two plots were similar in plant species composition which suggested that most regrowth in the burned area was from rootstocks which survived the fire. The plant data were submitted to a cluster analysis that revealed nine separate species associations, six of which occured in the burned area and eight of which occured in the control. These were subsequently treated as habitats for purposes of comparison with small mammal distributions. The burned area showed a greater productivity in flowers and fruits although total productivity in the control area was higher due to a large contribution from the non-vascular component. Maximum aerial productivity as dry wieght was measured at 157.1 g/m and 207.8 g/m for the burn and control respectively. Microtus pennsylvanicus and Clethrionomys rutilus were the two most common small mammals encountered; Microtus xanthognathus, Synaptomys borealis, and Phenacomys intermedius also occured in the area. Populations of M. pennsylvanicus and C. rutilus were high during the summer of 1973; however, M. pennsylvanicus was rare on the control but abundant on the burn, while C. rutilus was rare on the burn but abundant in the control. During the summer of 197^ populations declined, with the result that few voles of any species were caught in the burn while equal numbers of the two species were caught in the control. During the summer of 1973 M. pennsylvanicus showed a positive association to the most productive habitat type in the burn which was avoided by C. rutilus. In the control £• rutilus showed a similar positive association to the most productive habitat type which was avoided by M. pennsylvanicus. In all cases for the high population year of 1973# the two species never overlapped in habitat preference. When populations declined in 197^f "both species showed a strong association for the most productive habitat in the control. This would suggest that during a high population year, an abundant species can exclude competitors from a chosen habitat, but that this dominance decreases as population levels decrease. It is possible that M. pennsylvanicus is a more efficient competitor in a recently burned environment, while C. rutilus assumes this role once non-vascular regrowth becomes extensive.

Palaeopigment accumulation and implcations for paleolimnology over the lost century for two Ontario lakes

Crawford Lake is a meromictic lake, which is 24 m deep and has an area of 2.5 ha, and has never been reported to have mixed below 16 m. Lady Evelyn Lake, which became a reservoir when a dam was built in 1916, is dimictic with a maximum depth of about 35 m. 1 My research proved that both native chlorophylls and the ratio of chlorophyll derivatives to total carotenoids were better preserved in the shallower lake (Crawford Lake) because it was meromictic. Thus the anaerobic conditions in Crawford Lake below 16 m (monimolimnion) provide excellent conditions for pigment preservation. Under such conditions, the preservation of both chlorophylls and carotenoids, including oscillaxanthin and myxoxanthophyll, are extremely good compared with those of Lady Evelyn Reservoir, in which anaerobic conditions are rarely encountered at the mud-water interface. During the period from 1500 to 1900 A. D. in Crawford Lake, the accumulation rates of oscillaxanthin and myxoxanthophyll were extremely high, but those of chlorophyll derivatives and total carotenoids were relatively low. This was correlated with the presence of a dense benthic mat of cyanobacteria near the lake's chemocline. Competition for light between the deep dwelling cyanobacteria and overlying phytoplankton in this meromictic lake would have been intensified as the lake became more and more eutrophic (1955-1991 A. D.). During the period from 1955 to 1991 A. D., the accumulation rates of chlorophyll derivatives and total carotenoids in the sediment core from Crawford Lake (0-7.5 cm, 1955-present) increased. During this same period, the accumulation rates of cyanobacterial pigments (Le. oscillaxanthin and myxoxanthophyll) declined as the lake became more eutrophic. Because the major cyanobacteria in Crawford Lake are benthic mat forming Lyngbya and Oscillatoria and not phytoplankton, eutrophication resulted in a decline of the mat forming algal pigments. This is important because in previous palaeolimnological studies the concentrations of oscillaxanthin and myxoxanthophyll have been used as correlates with lake trophic levels. The results of organic carbon a13c analysis on the Crawford Lake sediment core supported the conclusions from the pigment study as noted above. High values of a13c at the depth of 34-48 cm (1500-1760 A. D.) were related to a dense population of benthic Oscillatoria and Lyngbya living on the bottom of the lake during that period. The Oscillatoria and Lyngbya utilized the bicarbonate, which had a high a 13C value. Very low values were found at 0-7 cm in the Crawford sediment core. At this time phytoplankton was the main primary producer, which enriched 12C by photosynthetic assimilation.

"Man of science, man of faith" : Lost, consumer agency and the fate/free will binary in the post-9/11 context

In 2004, Lost debuted on ABC and quickly became a cultural phenomenon. Its postmodem take on the classic Robinson Crusoe desert island scenario gestures to a variety of different issues circulating within the post-9II1 cultural consciousness, such as terrorism, leadership, anxieties involving air travel, torture, and globalization. Lost's complex interwoven flashback and flash-forward narrative structure encourages spectators to creatively hypothesize solutions to the central mysteries of the narrative, while also thematically addressing archetypal questions of freedom of choice versus fate. Through an examination of the narrative structure, the significance of technological shifts in television, and fan cultures in Lost, this thesis discusses the tenuous notion of consumer agency within the current cultural context. Furthermore, I also explore these issues in relation to the wider historical post-9/II context.

"All The Best Cowboys Have Daddy Issues": [Post]Oedipal Fatherhood And Subjectivity In ABC's Lost

ABC's popular television series Lost has been praised as one of the most innovative programs in the history of broadcast television primarily due to its unique storytelling content and structure. In this thesis, I argue that in spite of its unconventional stances in terms of narrative, genre, and character descriptions, Lost still conforms to the conventional understanding of family, fatherhood, and subjectivity by perpetuating the psychoanalytic myth of the Oedipus complex. The series emphasizes the centrality of the father in the lives of the survivors, and constructs character developments according to Freud's essentialist and phallocentric conception of subjectivity. In this way, it continues the classic psychoanalytic tradition that views the father as the essence of one's identity. In order to support this argument, I conduct a discursive reading of the show's two main characters: Jack Shepherd and John Locke. Through such a reading, I explore and unearth the mythic/psychoanalytic importance of the father in the psychology of these fictional constructs.

Report - Loss Due to Ice Rankine Station - 1938 through 1941

A report outlining the expenses of loss due to ice from the year 1938 through 1941 at the Rankine Station. Included in the report is the lost income due to power outages, operating labour, operating material and the sum of these costs per annum.

Property Lost, Captured, or Destroyed by the Enemy 1812-14 (1824)

Government report in congress discussing property lost, captured, or destroyed by the British during the War of 1812.

Reduce Stress of Handling to Improve Productivity of Livestock

The article focuses on stress factors, which include: Genetic Background, Individual Differences, Past Experiences. The conclusion of the article states "reducing handling stress of animals will improve their weight gain, reproductive performance, and ability to resist disease".

Clipping from a Town Council meeting at which estimates of the costs of Railway Line no. 1 and Line no. 2 were submitted by the office of Port Dalhousie and Thorold Railway

Clipping from a Town Council meeting at which estimates of the costs of Railway Line no. 1 and Line no. 2 were submitted by the office of Port Dalhousie and Thorold Railway. The estimate was submitted by S.D. Woodruff and George Rykert, president. There is also a disclaimer in which Calvin Phelps claims to have resigned as director of the Port Dalhousie and Thorold Railway when he discovered that the company had no intention to adhere to the original plan for building and running the road, Aug. 1854.

Report by Jacob Misner on setting contracts for deepening and clearing ditches and estimates of quantities and costs of marsh drainage

Report by Jacob Misner on setting contracts for deepening and clearing ditches and estimates of quantities and costs of marsh drainage (3 ½ pages, handwritten). This is marked as a copy, July 14, 1855.

List which includes costs, plans and receipts for amounts received between S.D. Woodruff and Boyd and Schurr

List (8 pages, handwritten) which includes costs, plans and receipts for amounts received between S.D. Woodruff and Boyd and Schurr, Dec. 3, 1875.