The use of δ18O- PO4 analysis was assessed for the Grand River, a highly impacted river in Southern Ontario that receives inputs from 30 WWTPs. Significant nutrient inputs within the watershed have led to prolific aquatic plant growth, particularly within the central Grand River where this study is focused. Two of the largest WWTPs in the watershed fall within this region and these plants are in close proximity to each other (approximately 20 km apart). Various laboratory tests were carried out to assess the suitability of several DOM removal methods on Grand River water and WWTP effluent prior to mass spectrometric analysis with varying results. Sample analysis showed all river sites to possess δ18O- PO4 values that were elevated relative to equilibrium. These sites are not equilibrium-controlled and, instead, possess δ18O- PO4 signatures controlled by either source inputs, or isotopic fractionation. The second WWTP was shown to deliver PO43- that was elevated relative to equilibrium. WWTP effluent in this study displayed a large δ18O -PO4 range, ranging from 10.4 to 22.9‰. Most of the variation in isotopic composition was found at the second plant, which had high soluble reactive phosphorus (SRP) and a range of 12.5 to 22.8‰ (n = 3). The first plant showed little variation with much lower SRP and a mean value of 11.4 (SD ± 1.0‰, n = 2). The elevated δ18O- PO4 signatures collected from the second WWTP suggest that this plant is supplying the Grand River with isotopically distinct PO43-. This could be used as a way to establish the effect of the second WWTP on the downstream PO43- pool. Phosphate uptake and release by the epilithon and seston were measured using 32P-PO4 additions in recirculating beaker experiments. Two sites, one downstream of the first WWTP and one below the second WWTP, were assessed for gross and net PO43- uptake rates. The gross uptake rates at both sites were low (0.04 to 0.10 µg P cm-2 h-1), with long turnover times for the dissolved phosphate pool (12 to 40 h). Long uptake lengths (30 to 144 km) were measured, indicating low nutrient retention capabilities downstream of the two WWTPs. These significant P contributions appear to have large-scale effects on the river’s P-kinetics, limiting its ability to act as a net nutrient sink even in the more productive summer months. The biomass response below the WWTPs is insufficient to compensate for the elevated PO43- concentrations and low rates of PO43- uptake. Due to the limited use of δ18O -PO4 analysis in river systems, no model exists for predicting the response of δ18O -PO4 with distance downstream of a point source. Coupling rates of PO43- uptake and release with the effluent δ18O -PO4 values provides such a model and generates guidance for future use of this method in lotic environments. WWTP “plume chases” were previously carried out in the Grand River, and involved measuring SRP at several sites downstream of the WWTP discharge points. SRP was used as a proxy for PO43- concentration in this study, and is operationally defined by what passes through a 0.20-µm membrane filter and is molybdate reactive. Best-fit estimates of PO43- uptake and release were determined using these plume chase events. The rates calculated using the 32P-PO4 uptake and release beaker experiments were up to 50 times lower than the best-fit parameters. This exercise illustrates the unsuitability of relaying estimates of P kinetics collected through beaker experiments to an ecosystem level. Model predictions for the river reach below the second WWTP show that effluent δ18O -PO4 signatures should be observable many kilometres from the plant. Because of the unique mean isotopic composition observed for the second WWTP, sampling could occur at a variety of locations downstream to observe the effect of this plant on the river. The river reach below the first WWTP reduces the incoming P loads much quicker than the second reach, which is in part due to the much lower effluent SRP released by the first plant. It is still possible to isolate effluent derived δ18O-PO4 values downstream of this plant. The return to equilibrium is projected to occur several kilometers from the first plant’s confluence, suggesting the applicability of this method in both stream reaches. It would appear δ18O -PO4 could be a valuable tool for eliciting information on P cycling in effluent-impacted river ecosystems, with the Grand River possessing elevated but seemingly typical uptake lengths amongst eutrophic streams.

Stable isotope analysis is a tool employed in ecological studies to provide information on the movement of elements and energy through a system. The stable carbon and nitrogen isotope analysis of aquatic organisms has been commonly used to address questions related to energy transfer between organisms and to identify the reliance of aquatic organisms on different sources of organic matter within the system. Within the rivers, stable isotope analysis has been used to describe food webs and connect conditions within the watershed with the river. The Grand River watershed is a predominantly agricultural watershed which receives inputs from ~26 MWWTP and is managed for flow by multiple large reservoirs and weirs. The stable isotope values of aquatic organisms within this watershed were analyzed from samples collected between May and September, 2007. Sites were selected in relation to three different municipal waste water treatment plants (MWWTP) in the centre of the watershed and along a 200 km stretch of the main stem of the Grand River. Results show that stable isotope analysis can be used to differentiate organisms collected from different sites and which represent different trophic levels within the river system under select conditions. Sites which are influences by inputs from organic matter or nutrients within distinct isotope values can be distinguished easily if the input is large and the isotope values are significantly distinct from background values. For smaller inputs changes in stable isotope values were not observed relative the background variability in the system. In this case, sites should be selected to allow for the characterization the variation in isotope values already occurring within the river. Samples collected later in the growing seasons have more distinctive isotope values are between sites. At sites where seasonal variation is greater, the organisms collected may not show a clear separation between trophic levels. A lack of knowledge regarding the time period represented by the tissues of the organisms challenges interpretation these results. It is concluded that stable isotope values of aquatic organisms reflected the condition of this watershed. For nitrogen increasing loads from point sources were accompanied by increasing isotope values. Stable isotope values decreased over the river reach where recovery in river condition occurs as a result of ground water inputs. The influence of individual large MWWTP and reservoirs was observable and the management of the MWWTP and reservoir appears to affect the changes in isotope values which are observed.

Stable isotope analysis is a tool employed in ecological studies to provide information on the movement of elements and energy through a system. The stable carbon and nitrogen isotope analysis of aquatic organisms has been commonly used to address questions related to energy transfer between organisms and to identify the reliance of aquatic organisms on different sources of organic matter within the system. Within the rivers, stable isotope analysis has been used to describe food webs and connect conditions within the watershed with the river. The Grand River watershed is a predominantly agricultural watershed which receives inputs from ~26 MWWTP and is managed for flow by multiple large reservoirs and weirs. The stable isotope values of aquatic organisms within this watershed were analyzed from samples collected between May and September, 2007. Sites were selected in relation to three different municipal waste water treatment plants (MWWTP) in the centre of the watershed and along a 200 km stretch of the main stem of the Grand River. Results show that stable isotope analysis can be used to differentiate organisms collected from different sites and which represent different trophic levels within the river system under select conditions. Sites which are influences by inputs from organic matter or nutrients within distinct isotope values can be distinguished easily if the input is large and the isotope values are significantly distinct from background values. For smaller inputs changes in stable isotope values were not observed relative the background variability in the system. In this case, sites should be selected to allow for the characterization the variation in isotope values already occurring within the river. Samples collected later in the growing seasons have more distinctive isotope values are between sites. At sites where seasonal variation is greater, the organisms collected may not show a clear separation between trophic levels. A lack of knowledge regarding the time period represented by the tissues of the organisms challenges interpretation these results. It is concluded that stable isotope values of aquatic organisms reflected the condition of this watershed. For nitrogen increasing loads from point sources were accompanied by increasing isotope values. Stable isotope values decreased over the river reach where recovery in river condition occurs as a result of ground water inputs. The influence of individual large MWWTP and reservoirs was observable and the management of the MWWTP and reservoir appears to affect the changes in isotope values which are observed.

Bythotrephes longimanus, a predatory exotic cladoceran, has spread rapidly to numerous lakes through the Laurentian Great Lakes region of Ontario and North America. Post-invaded lakes are known to have reduced zooplankton species richness, biomass and altered community structure. Bythotrephes may also affect the diet and trophic position of macroinvertebrate predators and prey species for fish (e.g., Mysis relicta). However, the effects of this species in altering higher trophic levels remain largely unexamined. Using a combined approach of stable isotope (d13C and d15N) and THg analysis, the trophic position of Bythotrephes in two invaded lakes was investigated. Based on d15N values, Bythotrephes shared a similar trophic position to native macroinvertebrate predators (9 and 7‰ for Peninsula and Harp lakes, respectively). Using a mixing model and stomach content analysis we show that, despite low and patchy lake abundance, Bythotrephes may be a key prey item to fish and has approximate dietary contributions similar to native prey items, such as zooplankton, Chaoborus and Mysis. In both lakes, Hg conformed to predicted biomagnification trends as indicated by 15N. When Bythotrephes invades lakes with native macroinvertebrate predators, it inserts itself into the same trophic position and does not have major effects on food web length. / Thesis (Master, Biology) -- Queen's University, 2008-01-10 22:00:22.188

Ridanäs was an important port of trade on the island of Gotland, Sweden, in use during the 7-11th centuries, AD. Excavations have revealed the presence of two Viking Age (800-1070 AD) graveyards containing over 80 individuals. This study examined the remains of 60 of these individuals buried in the Viking graveyards. Strontium isotope analysis was used to determine whether they were local or non-local to the trading port. It was hypothesized that the Ridanäs population would consist of locals and non-locals who came to Gotland to take advantage of its successful trade economy. 13 archaeological fauna samples were analyzed in order to define the local bioavailable strontium isotope baseline range. Results showed that only 4 of the 60 individuals were non-local to Gotland, indicating that non-locals did not seek long-term residency at this port of trade.

Thesis (M.S.F.S.) / Positive identification of skeletonized human remains is a difficult task when dental records and/or DNA are unavailable. Through archaeological research, strontium (Sr) isotope analysis has successfully been used to trace an individual back to their place of birth using cortical bone and tooth enamel. This method has the potential, in forensic anthropological science, to help narrow down the search for missing persons to a specific geographical location. It has not been tested thoroughly on modern populations though, which is needed before applying in a forensic setting. This study used dental enamel from teeth of 78 individuals in the New England region of the United States (U.S.). The birthplaces represented by these individuals include New England and the greater Northeast of the U.S., Northwest region of the U.S., Central America, Caribbean Islands, West Africa, and Europe. Local faunal and water samples were also collected for local range comparisons. The samples were cleaned, approximately 10 mg of enamel removed from each tooth, acid washed, dried, and dissolved in nitric acid before analyzing the samples using a thermal ionization mass spectrometer (TIMS) for analysis of 87Sr/86Sr ratios. The human 87Sr/86Sr ratios were grouped by geographical region. An analysis of variance was used to test for regional variation and significant differences were found. The samples from the U.S. (excluding those from the Northwest) were significantly different from the samples in Central America, Caribbean Islands, West Africa, and Europe. Central American samples were also significantly different from the other groups. No significant differences were observed between the Caribbean Islands, West Africa and Europe. A significant difference was seen between the strontium ratios in the West Africa group based on bottled water vs. tap water that individuals reported drinking. The faunal samples from Pembroke, MA and water sample from Braintree, MA were not significantly different from the New England human samples, but the Brighton, MA water sample was significantly different. Based on the data, regional differences in 87Sr/86Sr ratios are detectable using strontium isotope analysis, yet a larger sample size for each of the regions is needed to strengthen the statistical results. The results suggest that the differences observed are due to a combination of geological effects and influences from the globalization of food. Further research is warranted by combining the analysis of hydrogen (δ2H) and oxygen (δ18O) isotopes to the strontium analysis. This will complement the strontium data by providing more insight to the local drinking water and potential effects of an increasingly homogenous diet within cultural regions.

This thesis applies stable isotope analysis to the study of diet from a rural Roman estate, Vagnari (1st – 4th centuries AD), in southern Italy. The major objectives of this research are to identify the types of food eaten in the Vagnari skeletal sample from stable isotope ratios, as well as to explore individual variation in diet in the sample. Isotopic composition of collagen and carbonate indicate a diet heavy in C₃ plants with the incorporation of some animal-based proteins. Isotopes of carbon from collagen (δ¹³C) were relatively consistent across the sample, with some variation according to burial type. Nitrogen (δ¹⁵N) values varied with age-at-death and the number of grave goods buried with an individual, suggesting possible status-based variation in diet. Carbon isotopes from carbonate (δ¹³Cₐₚ) suggested variation in total diet with increased age-at-death. Isotope ratios from Vagnari were also compared with other Imperial Italian sites to situate the diet within a broader Roman context. Isotopically, diets at Vagnari were most similar to other inland and rural sites, and distinct from coastal urban diets based on marine fish. These results indicate the diversity in foods eaten in the Roman Empire, both at a local site level and between different settlements. Studying diet from Vagnari provides another window into the lives of people who lived and worked on industrial estates, and bolsters knowledge of the diets of rural residents, which are underrepresented in the literature. / Thesis / Master of Arts (MA)

Applications of lead and strontium isotope analysis were made on archaeological materials from three different contexts in both the Old and New Worlds. These materials comprised pre-Hispanic glaze painted ceramics from Arizona, U.S.A., glass beads from late first millennium AD Igbo-Ukwu, Nigeria, and copper-based metals from early first millennium AD Kissi, Burkina Faso. All materials contain lead at major, minor, or trace concentrations, and lead isotope analysis was employed to determine a provenance for that lead. Strontium isotope analysis also was applied to glass beads from Igbo-Ukwu to determine provenance(s) for strontium found in the glass. Furthermore, application of elemental composition analysis was or had been employed on all samples for additional data comparisons within assemblages and with comparable archaeological materials.Results of these analyses determined, in most cases, regional provenance with high degrees of confidence for lead contained in the analyzed samples. Strontium and elemental composition analysis data also proved valuable in confirming the regional provenance of the raw glass used to produce the glass beads. Leads in the glaze paints from Arizona, which demonstrated a range of resources exploitation, were confidently restricted to a few regions for their procurement. Likewise leads in most glass beads from Igbo-Ukwu were confidently restricted to two main source regions, with a third strong contender also being identified. The elemental composition and strontium isotope data determined with confidence the production regions for the primary raw glasses used to make the glass beads. Finally, leads in copper-based metals from Burkina Faso also were restricted to a few regions, although some inconclusiveness in provenance determination was attributed to mixing of metals from difference sources.These results confirm the utility of heavy isotope analysis of archaeological materials for provenance determination. The combination of these data with elemental composition analyses further confirm the interpretive strength of combining independent but related sets of analytical data for exploring questions of archaeological provenance. With improvements in instrument technology and application in the past two decades, very high precision and high accuracy analyses can be made which eliminate some earlier concerns of heavy isotope applications in archaeology.

Feeding experiments were conducted on Atlantic pollock (Pollachius virens) to examine the variability in tissue fatty acid (FA) composition and stable carbon isotope fractionation of FA during digestion, assimilation and mobilization of lipids. The FA profiles and compound-specific carbon isotopes of chylomicrons, liver, muscle and fasted serum were compared to diet. FA analysis demonstrated similarity among tissue groups despite differences in feeding states. The FA results indicate the blood of post-prandial fish may serve as an alternative to tissue biopsies for the estimation of marine fish diets with compound-specific isotope analysis (CSIA). Despite similarity among FA profiles, the carbon isotope discrimination factors of FA varied independently, which suggests that fractionation is influenced by the degree to which individual FA are oxidized. These results provide preliminary information that is necessary in order to use CSIA to estimate the effects of fish diets.

Individual niche variation is increasingly being demonstrated in animal populations in a wide variety of species and taxa. Niche variation among individuals has important implications for the ecology, evolution and management of animal populations and is a subject of increasing interest. However, despite its widespread occurrence the causes and consequences of individual niche variation remain poorly understood. In this thesis I use the European badger (Meles meles), a well studied species of high ecological interest, as a model system to investigate individual niche variation. In order to achieve this I combine information on individual foraging niches derived via stable isotope analysis (SIA) of badger vibrissae with detailed life history and ecological data from a long-term study population to investigate the incidence, cause and consequence of individual niche variation within badger social groups. First I use the biomarker Rhodamine B to investigate vibrissae growth rates and patterns in badgers and demonstrate that the isotopic composition of a single vibrissa likely reflects diet over several months (Chapter 2). Next I explore the use of SIA as a tool to investigate badger diet, by comparing isotopic patterns to seasonal changes in diet measured using faecal analysis (Chapter 3). My results provide validation that SIA is powerful tool for investigating foraging variation in this species, and suggest that within badger populations substantial dietary variation may occur among individuals. Further investigation of isotopic variation Indicates that individuals within social groups differ markedly and consistently in their isotopic signature, independent of age and sex effects and that in some instances these differences are remarkably consistent across year (Chapter 4).This suggesting long term individual specialisation (Chapter 4). I find that the degree of this individual specialisation, and the relationship between specialisation and body condition is influenced by competition for resources (Chapter 5). Social groups with higher levels of competition exhibit greater specialisation and specialised individuals within these highly competitive environments are in better condition. Finally, I discuss the implications of these results for individual niche variation, for the application of SIA to study this behaviour and for badger ecology generally (Chapter 6). I also outline future directions for further research.