Francis Xavier Garneau, the French-Canadian historian, gave the name Laurentian mountains to the dissected edge of the Canadian Shield along the St. Lawrence valley, and the early geologists adopted the same name for the complex of metamorphic and igneous rocks in this area. [...]

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Forest clearance can affect the levels of dissolved organic carbon (DOC), nutrient concentrations and algal biomass in streams, but the possible effect of these inputs on downstream lakes is usually surmised rather than demonstrated. To evaluate the effect of forest clearance on DOC and nutrient cycling in lakes, DOC, total phosphorus (TP), total nitrogen (TN) and chlorophyll (chl a) concentrations were measured in 47 Canadian Shield lakes in Quebec. Of these lakes, 25 were located in drainage basins that were partially clear-cut one to four years previously. In the disturbed sites, an uncut 20-m bufferstrip was left around the lakes and permanent water courses. / To account for differences among the watersheds that are not related to forest harvesting, I also collected a series of catchment and morphometric variables (watershed area, lake area, drainage ratio, forest, wetland, and upstream lake area, watershed slope, water residence time and lake depth). Lake characteristics in undisturbed and disturbed watersheds were compared to determine if forest clearance has a detectable effect on the water quality of downstream lakes. Although comparisons of seasonal and monthly means of the water quality variables between disturbed and reference sites were inconclusive, likely because of high natural variability, the size of the clear-cut was significantly related to means of the water quality characteristics. DOC, TP, TN and chl a increased in lake water with the area of the clear-cuts when large portions of the watershed ($>$50%) were cleared. The results of this study suggest that logging has an effect on water quality and even though a bufferstrip of twenty meters reduces this effect largely, it may not be enough to provide complete protection against the effects of logging activities.

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Un recueil de toutes du CRSNG détenues à l'université Laurentienne durant 2003-2004. A booklet of all NSERC grants held at Laurentian University in 2004-2005. / CRSNG et l'université Laurentienne NSERC and Laurentian University

The Laurentian Great Lakes are the largest system of freshwater on earth containing 22% of the world’s supply. Although part of a single system, each lake shows substantial variation regarding physical, chemical and biological parameters. The main goals of this thesis were to characterize the nutrient status of natural phytoplankton communities while comparing several commonly used measurements of nutrient status and Chlorophyll a (Chl a) fluorescence measurements. The study sites include the western basin (WB), west-central basin (WCB), and central basin (CB) of Lake Erie, the Bay of Quinte in Lake Ontario, and Colpoys Bay in Lake Huron. Independent measures of nutrient status were assessed by measurements of nitrogen (N) debt, phosphorus (P) debt, particulate C:N:P ratios, and alkaline phosphatase activity (APA). Variable fluorescence of chlorophyll a was measured by pulse amplitude modulated (PAM) fluorometry and fast repetition rate (FRR) fluorometry in parallel with the independent measures. In 2005, the phytoplankton communities in Lake Erie were generally N deficient in May, P deficient in June, and neither N nor P deficient in September. The maximum dark adapted quantum yield (Fv/Fm) measured by PAM or FRRF was lower in May and June, and maximal in September, while the functional absorption cross section of photosystem II (σPSII) was maximal in May and June, and minimal in September. Relationships between the variable fluorescence indicators and independent measures of nutrient status showed strong associations with N or P deficient sites having low Fv/Fm and high σPSII. In 2006, the electron transport rate (ETR) and the initial slope (α) derived from the PAM fluorescence rapid light-response curves (RLC) were compared to independent measures and Fv/Fm measurements in Lake Erie. Relationships between ETR, α, independent measures of nutrient status, and Fv/Fm measurements revealed strong associations with nutrient status. Confirming previous reports, N deficiency was highest in the WB during isothermal conditions while P deficiency was highest in the CB during summer stratification. The fluorescence parameters generally decreased as the severity of N and P deficiency increased. N and P enrichment assays also revealed increased values of Fv/Fm, ETR, and α from N and P deficient samples over twenty-four hours. Additionally, spatial variability of P status was evaluated during summer stratification. Colpoys Bay, the most oligotrophic site, had the strongest P deficiency, and evidence for existence of P deficiency was weakest in the Bay of Quinte, the most eutrophic site. Nutrient enrichment assays revealed that all fluorescence parameters showed a positive response to P additions in oligotrophic sites, with no response in eutrophic sites. Community structure was also associated with nutrient status and Chl a fluorescence at all locations. In P deficient sites, nano-flagellates such as chrysophytes and cryptophytes were prevalent; cyanobacteria were dominant at sites that displayed N deficiency.

The Laurentian Great Lakes are the largest system of freshwater on earth containing 22% of the world’s supply. Although part of a single system, each lake shows substantial variation regarding physical, chemical and biological parameters. The main goals of this thesis were to characterize the nutrient status of natural phytoplankton communities while comparing several commonly used measurements of nutrient status and Chlorophyll a (Chl a) fluorescence measurements. The study sites include the western basin (WB), west-central basin (WCB), and central basin (CB) of Lake Erie, the Bay of Quinte in Lake Ontario, and Colpoys Bay in Lake Huron. Independent measures of nutrient status were assessed by measurements of nitrogen (N) debt, phosphorus (P) debt, particulate C:N:P ratios, and alkaline phosphatase activity (APA). Variable fluorescence of chlorophyll a was measured by pulse amplitude modulated (PAM) fluorometry and fast repetition rate (FRR) fluorometry in parallel with the independent measures. In 2005, the phytoplankton communities in Lake Erie were generally N deficient in May, P deficient in June, and neither N nor P deficient in September. The maximum dark adapted quantum yield (Fv/Fm) measured by PAM or FRRF was lower in May and June, and maximal in September, while the functional absorption cross section of photosystem II (σPSII) was maximal in May and June, and minimal in September. Relationships between the variable fluorescence indicators and independent measures of nutrient status showed strong associations with N or P deficient sites having low Fv/Fm and high σPSII. In 2006, the electron transport rate (ETR) and the initial slope (α) derived from the PAM fluorescence rapid light-response curves (RLC) were compared to independent measures and Fv/Fm measurements in Lake Erie. Relationships between ETR, α, independent measures of nutrient status, and Fv/Fm measurements revealed strong associations with nutrient status. Confirming previous reports, N deficiency was highest in the WB during isothermal conditions while P deficiency was highest in the CB during summer stratification. The fluorescence parameters generally decreased as the severity of N and P deficiency increased. N and P enrichment assays also revealed increased values of Fv/Fm, ETR, and α from N and P deficient samples over twenty-four hours. Additionally, spatial variability of P status was evaluated during summer stratification. Colpoys Bay, the most oligotrophic site, had the strongest P deficiency, and evidence for existence of P deficiency was weakest in the Bay of Quinte, the most eutrophic site. Nutrient enrichment assays revealed that all fluorescence parameters showed a positive response to P additions in oligotrophic sites, with no response in eutrophic sites. Community structure was also associated with nutrient status and Chl a fluorescence at all locations. In P deficient sites, nano-flagellates such as chrysophytes and cryptophytes were prevalent; cyanobacteria were dominant at sites that displayed N deficiency.

I investigated whether Neogobius melanostomus, an invader of biodiversity “hot-spots” in Ontario facilitates or inhibits unionid mussel recruitment by serving as a host or as a sink for their parasitic larvae (glochidia). Infestation and metamorphosis rates of four mussel Species at Risk (Epioblasma torulosa rangiana, Epioblasma triquetra, Lampsilis fasciola, and Villosa iris) and one common species (Actinonaias ligamentina) on N. melanostomus were compared to rates on known hosts in the laboratory. All species successfully infested N. melanostomus, but only E. triquetra, V. iris, and A. ligamentina successfully metamorphosed, albeit at low rates. Neogobius melanostomus collected from areas of unionid occurrence in the Grand and Sydenham rivers exhibited body burdens of 39.4% and 5.1%, respectively. Analyses indicate that N. melanostomus serves more as a sink for glochidia than as a host for unionids, thereby limiting recruitment, which is a novel way by which N. melanostomus is affecting native mussel species.

The dichotomy of contrastive and allophonic phonological relationships has a long-standing tradition in phonology, but there is a growing body of research (see Hall, 2013, for a review) that points to phonological relationships that fall between contrastive and allophonic. The criteria most commonly used to define phonological relationships or resolve cases of ambiguous phonological relationships – namely (a) predictability of distribution, and (b) lexical distinction – are not always able to account for observed sound patterns. The main goal of this dissertation is to identify and apply quantitative measures (relative frequency and minimal pair counts) to the traditional criteria in order to better account for cases of intermediate phonological relationships or, in other words, to account for different strengths and degrees of contrast. Twenty native speakers of Laurentian French (LF) participated in Experiment 1, an AX discrimination task, and Experiment 2, a four-interval AX (4IAX) task, which tested the broader relationships of allophony and contrast. It was hypothesized, based on previous experiments (Boomershine et al., 2008; Dupoux et al., 1997; Ettlinger & Johnson, 2009; Johnson & Babel, 2010; Kazanina et al., 2006; Peperkamp et al., 2003; Pruitt et al., 2006), that phones in an allophonic relationship would be more difficult to perceive than phones in a contrastive relationship. Results confirmed previous findings, with longer reaction times for allophonic pairs as compared to contrastive pairs in the AX task (p<.001), as well as in the 4IAX task (p = .004). For Experiments 3, 4 and 5, thirty native speakers of LF participated in an AX, a 4IAX and a similarity rating task. Measures of functional load, frequency and acoustic similarity were applied to pairs of phones in allophonic and phonemic relationships in order to quantify the degree of contrast between pairs. If a gradient view of contrast was supported, it was hypothesized that High Contrast vowels [a-ɔ] would yield higher accuracy, faster reaction times and lower similarity ratings; Low Contrast vowels [y-ʏ] would yield lower accuracy, slower reaction times and higher similarity ratings; and Mid Contrast vowels [o-ʊ] would yield results that fell between the two extremes. If, on the other hand, a strict binary interpretation of contrast was supported, High Contrast vowels and Mid Contrast vowels should yield similar results since these vowels are considered to be in a phonemic relationship, with higher accuracy, faster reaction times and lower similarity ratings, while Low Contrast vowels [y-ʏ], in an allophonic relationship, should yield lower accuracy, slower reaction times and higher similarity ratings. The results from Experiments 3 (AX) and 4 (4IAX) show that the High Contrast pairs yielded significantly higher accuracy scores and faster reaction times than both Mid and Low Contrast pairs (Experiment 3: p<.001 for both High vs. Mid and High vs. Low comparisons; Experiment 4: p = .039 for High vs. Mid, p = .055 for High vs. Low comparisons). However, no significant differences were found between Mid and Low Contrast pairs in these two experiments. The results from Experiment 5 matched gradient predictions, showing significant differences between High, Mid and Low conditions, with similarity being judged highest for Low pairs, lowest for High pairs, and ratings for Mid pairs falling exactly between the other two levels (p<.001 for all comparisons). While results do not perfectly match gradient predictions, the findings provide evidence counter to a strict binary interpretation of contrast since traditionally phonemic pairs (High [a-ɔ] and Mid [o-ʊ]) were significantly different from one another in all experiments. The lack of difference between Mid and Low Contrast pairs could be due to the measures of functional load and frequency for Mid pairs being closer to those of Low pairs, and thus did not reflect a level of contrast that was equidistant between High and Low Contrast. Nevertheless, taken together with the results from Experiment 5, the results appear to support a gradient view of phonological relationships rather than a strictly dichotomous view. Quantitative measures therefore show promise in accounting for cases of intermediate phonological relationships.

Alternative reproductive tactics (ARTs), occur where members of one sex of a species have two or more strategies of obtaining fertilization. The tactics differ in behavioural approaches to reproduction, but also commonly differ in physiological and morphological traits. The round goby, Neogobius melanostomus, is a globally invasive species with male ARTs. How behaviour may influence invasiveness in round goby has been of recent interest, but researchers have not considered the role or impact that male ARTs may have. I compared guarder and sneaker male round goby, assessing differences in their boldness, activity, exploration, sociality, aggression, startle responses, and dispersal tendencies. Sneaker males were more bold, active, and explorative while guarder males were more aggressive. In addition, I studied whether more guarders or sneakers are caught in a population survey study and how variation in a common round goby trapping method, minnow traps, may create catch biases. Two commonly employed minnow trap models include a black vinyl plastic coated metal trap (black traps) and a galvanized metal steel trap (silver traps). I investigated whether these black and silver traps and baited (corn) and unbaited traps differ in terms of the numbers, ART ratios, and sizes of round goby captured. I found silver traps captured 1.7 times more round goby than black traps, while baited traps captured 3.4 times more round goby than unbaited traps. Baited traps captured larger round goby and tended to capture more guarders than unbaited traps. I also found black traps captured larger males, but there was no difference in the size of females captured. Taken together my results indicate that care needs to be applied when making estimates of round goby populations in terms of the types of individuals present and the trapping method used. / Thesis / Master of Science (MSc)