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Hoary Bat (Lasiurus cinereus) is a migratory species known to travel long distances during migration. Little is known about its movement patterns during other periods. An adult male Hoary Bat that we radio-tagged in southwestern Ontario in summer was tracked using the Motus Wildlife Tracking System. It travelled a minimum of 827 km in a circular route over a 2-week period and was last recorded 46 km from the original capture site. Hoary Bat is highly vulnerable to being killed at wind turbines and its propensity to travel great distances during summer and migration may exacerbate the impacts of wind farms. [ABSTRACT FROM AUTHOR]

Abstract The process of systematically developing a sustainability vision is an important element of effective environmental management. Sustainability visions can, however, include contradictions and counterintuitive effects due to complex system behavior (e.g., feedback loops, multi-causality) and ambiguous system boundaries (e.g., choice of a scale, such as a regional or national scale). This paper proposes an innovative methodological framework for vision design and assessment (VDA) to analyze the sustainability of future visions on multiple scales with consideration of ecosystem services, and to test their plausibility based upon expert and local knowledge. First, requirements and functions of visionary system designs are identified. Second, a functional organizational analysis defines structures and processes that generate functions. Third, a literature review and participatory modeling process are conducted to analyze the system structures of visionary system designs using causal loop diagrams. Fourth, fuzzy cognitive mapping is used to assess visions based upon sustainability indicators. A case study on sustainable food systems in Southwestern Ontario, Canada, is provided to demonstrate the application of the methodology. Three designs of a sustainable food system were analyzed and tested: urban organic gardening, a local diversified organic food system and a globalized commodity-based organic food system. The results show the advantages and disadvantages of each system design and underline the sustainability benefits of a multi-scale food system based upon a combination of system designs. Highlights • Coherent sustainability visions are critical for effective environmental management. • We propose a framework to design and assess sustainability visions. • The framework uses functional analysis, conceptual modeling, fuzzy cognitive maps. • A case study in Ontario on sustainable food systems is provided. • The results show various sustainability benefits of a multi-scale food system. [ABSTRACT FROM AUTHOR]

Growing cover or winter crops and retaining crop residue on agricultural lands are considered beneficial management practices to address soil health and water quality. Remote sensing is a valuable tool to assess and map crop residue cover and cover crops. The objective of this study is to evaluate the performance of linear spectral unmixing for estimating soil cover in the non-growing season (November–May) over the Canadian Lake Erie Basin using seasonal multitemporal satellite imagery. Soil cover ground measurements and multispectral Landsat-8 imagery were acquired for two areas throughout the 2015–2016 non-growing season. Vertical soil cover photos were collected from up to 40 residue and 30 cover crop fields for each area (e.g., Elgin and Essex sites) when harvest, cloud, and snow conditions permitted. Images and data were reviewed and compiled to represent a complete coverage of the basin for three time periods (post-harvest, pre-planting, and post-planting). The correlations between field measured and satellite imagery estimated soil covers (e.g., residue and green) were evaluated by coefficient of determination (R2) and root mean square error (RMSE). Overall, spectral unmixing of satellite imagery is well suited for estimating soil cover in the non-growing season. Spectral unmixing using three-endmembers (i.e., corn residue-soil-green cover; soybean residue-soil-green cover) showed higher correlations with field measured soil cover than spectral unmixing using two- or four-endmembers. For the nine non-growing season images analyzed, the residue and green cover fractions derived from linear spectral unmixing using corn residue-soil-green cover endmembers were highly correlated with the field-measured data (mean R2 of 0.70 and 0.86, respectively). The results of this study support the use of remote sensing and spectral unmixing techniques for monitoring performance metrics for government initiatives, such as the Canada-Ontario Lake Erie Action Plan, and as input for sustainability indicators that both require knowledge about non-growing season land management over a large area.

Mainstream society’s perceptions of traditional Mennonites tend towards viewing them as technologically deficient. Yet, cell phones, computers, and tablets are increasingly prevalent within this population. Challenging stereotypes, this article considers digital technology usage by Old Colony Mennonites (OCM) in Southwestern Ontario (SWO). Rooted in the Anabaptist tradition, a lengthy history of migration led the OCM to settle in Mexico. Yet, due to economic circumstances, many continue to travel to and from SWO, resulting in a transformation; from maintaining an isolated lifestyle to one that includes some form of mainstream society. This shift includes digital technology usage, specifically texting, social media, and the Internet. Although research into Mennonite technology practice exists, these new forms of digital technologies have not received similar attention. Drawing on fieldwork conducted in 2012, this study took place in five Old Colony communities in SWO. Interviews, with both former and current OCMs, and others who have some connection to the Mennonites, suggest that the Old Colony navigate the lines between prescribed values and twenty-first century requirements in terms of a continuum, on their own terms. While digital technologies may create tensions within the community, they also act to blur lines between geographical boundaries, extend social networks, and allow OCMs to create their own vision of the society in which they wish to live.

Population growth in the groundwater-dependent municipalities of southwestern Ontario has prompted interest in the exploration for new, previously untapped, groundwater resources. In this study, the groundwater resource potential of the sediments infilling a deeply buried bedrock valley network centred beneath the Region of Waterloo and the counties of Brant and Hamilton-Wentworth are explored. The objectives of this study are to further refine valley location and geometry, understand infilling sediments and their hydrogeological properties, and characterize waters contained within the aquifers to inform future water management decisions. Results of a regional ground gravity survey were instrumental in locating buried bedrock valleys and guided follow-up drilling. Continuous sediment coring and monitoring well installations were completed to target thick and coarse-grained sediment packages that, based on existing borehole data, showed aquifer potential. Hydraulic testing and groundwater sampling results provided valuable insights into groundwater quantity and quality. Highly transmissive aquifers, some worth investigating further, have been identified within portions of the valley network. The aquifers appear to occur at a number of stratigraphic positions and do not necessarily occur as the deepest unit overlying bedrock. Bedrock topography likely played a role, however, in their preferential preservation. They are commonly overlain by thick sequences of relatively impermeable sediments, providing excellent protection from anthropogenic contamination. Information from water chemistry, however, does suggest hydraulic connection to the surface at some locations. Groundwater quality and quantity information combined with a conceptual three-dimensional geologic model aids in the selection of groundwater resource exploration targets within the untapped resources of the deep, Dundas buried valley sediments. [ABSTRACT FROM AUTHOR]

Regional-scale three-dimensional modelling of Quaternary sediments in the Orangeville Moraine area of southwestern Ontario has been completed as part of the Ontario Geological Survey groundwater initiative and provides an improved understanding of the glacial history and conceptual hydrostratigraphic framework for that region. Older (Marine Isotope Stage (MIS) 3-5) diamicton, glaciolacustrine, glaciofluvial, and rare nonglacial deposits forming regional aquitards and local aquifers are found in the northwestern part of the area. Catfish Creek Till, deposited during the Last Glacial Maximum (LGM) (MIS 2), forms a key aquitard and stratigraphic marker at depth. Diamicton, fine-textured glaciolacustrine sediments, and the gravel, sand, and silt conduit and subaqueous fan sediments that constitute the overlying Orangeville Moraine were deposited in an ice-walled lake formed between ice lobes during retreat from the LGM. Diamicton deposited during late-glacial ice margin fluctuations forms the upper aquitard unit and buries the edges of the moraine. The Orangeville Moraine is the largest aquifer in the area, and is partially confined by the upper tills. Thick fine-textured glaciolacustrine deposits, Catfish Creek Till, and older aquitards separate the moraine from bedrock aquifers across most of the area. Depending on hydraulic gradients, buried bedrock valleys with gravel and sand fills have the potential to recharge the bedrock aquifer. [ABSTRACT FROM AUTHOR]

High density air monitoring campaigns provide spatial patterns of pollutant concentrations which are integral in exposure assessment. Such analysis can assist with the determination of links between air quality and health outcomes, however, problems due to missing data can threaten to compromise these studies. This research evaluates four methods; mean value imputation, inverse distance weighting (IDW), inter-species ratios, and regression, to address missing spatial concentration data ranging from one missing data point up to 50% missing data. BTEX (benzene, toluene, ethylbenzene, and xylenes) concentrations were measured in Windsor and Sarnia, Ontario in the fall of 2005. Concentrations and inter-species ratios were generally similar between the two cities. Benzene (B) was observed to be higher in Sarnia, whereas toluene (T) and the T/B ratios were higher in Windsor. Using these urban, industrialized cities as case studies, this research demonstrates that using inter-species ratios or regression of the data for which there is complete information, along with one measured concentration (i.e. benzene) to predict for missing concentrations (i.e. TEX) results in good agreement between predicted and measured values. In both cities, the general trend remains that best agreement is observed for the leave-one-out scenario, followed by 10% and 25% missing, and the least agreement for the 50% missing cases. In the absence of any known concentrations IDW can provide reasonable agreement between observed and estimated concentrations for the BTEX species, and was superior over mean value imputation which was not able to preserve the spatial trend. The proposed methods can be used to fill in missing data, while preserving the general characteristics and rank order of the data which are sufficient for epidemiologic studies. [ABSTRACT FROM AUTHOR]

Cryptosporidium is a waterborne parasite that causes diarrheal disease in humans and in cattle. Risk factors for human illness include contact with surface water such as lakes and rivers, exposure to contaminated municipal drinking water, as well as zoonotic transmission from livestock and agriculture. The objectives of this study are twofold: 1) to describe the temporal distribution of cryptosporidiosis in Southwestern Ontario; and 2) to determine the distribution of human cryptosporidiosis, in relation to exposures such as cryptosporidium positive cattle farms, weather events, and hydrological factors. Seasonal trends in 214 bovine and 87 human cases were assessed using regression models that predicted monthly case counts in relation to observed monthly case counts. A case-crossover approach was used to evaluate acute associations between daily environmental exposures, such as weather, hydrology, the presence of Cryptosporidium positive cattle farms within the region, and the risk of human Cryptosporidium infection. Annual seasonality was found for both human cases and bovine cases with human cases peaking in mid-summer and bovine cases peaking in late winter to early spring. Bovine cases that occurred 21 days prior to human cases were associated with a three-fold increase in the odds of human case occurrence. At both 9 and 14 days prior to human case onset, the odds of a human case increased twofold per 10-degree Celsius increase in air temperature. These results provide a preliminary hypothesis for the zoonotic transmission of cryptosporidiosis from cattle to humans via the environment and suggest that the timing of environmental conditions in relation to case occurrence is biologically plausible. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Water Resources Journal / Revue Canadienne des Ressources Hydriques is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Processes of environmental dispossession have had dramatic consequences for dietary quality, cultural identity, and the integrity of traditional food systems (TFS) in many Indigenous populations. These transitions have not been documented among First Nation people in southwestern Ontario, and virtually no studies have investigated TFS in southern or urban regions of Canada. Nested within a larger community-centred project designed to better understand the social and spatial determinants of food choice and patterns of food security, the objective of this paper was to explore First Nation mothers' knowledge about access, availability, and practices relating to traditional foods in the city of London, Ontario, and nearby First Nation reserves. In 2010, twenty-five women participated in semi-structured interviews that were audio recorded, transcribed, and analyzed with input from community partners. Our results centre on the women's stories about access, preferences, knowledge, and sharing of traditional foods. Those living on a reserve relied more consistently on traditional foods, as proximity to land, family, and knowledge permitted improved access. Urban mothers faced transportation and economic barriers alongside knowledge loss related to the use and preparation of traditional foods. Overall our results demonstrate uneven geographic challenges for First Nation engagement in TFS, with urban mothers experiencing uniquely greater challenges than those residing on a reserve. [ABSTRACT FROM AUTHOR]

Wastewater reclamation is becoming an important alternative for sustainable water resources management and building climate change resiliency in many regions around the world. This research investigated the polishing of secondary effluents and combined sewer overflows (CSOs) by a laboratory-scale soil aquifer treatment considering local soils and wastewater characteristics of southwestern Ontario. Results show that high permeability soils of southwestern Ontario, have the ability to polish secondary effluents in terms of dissolved organic carbon, Escherichia coli, and total coliforms. Regarding the simulated CSOs, low to moderate improvements of wastewater quality were observed. Denitrification of secondary effluents improved significantly by the addition of readily available organic matter, which supports the importance of protecting recharge wetlands for groundwater quality protection. Soil aquifer treatment in southwestern Ontario is a feasible alternative for the recharge of non-potable and potable aquifers with secondary effluents. However, for potable aquifers further treatment of wastewater effluents may be required. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The lithostratigraphic term 'Eramosa' was introduced in Ontario more than a century ago to include a distinctive package of thin- to medium-bedded, black to medium-brown dolostones that make up key cuesta faces and railway roadcuts along the Eramosa River in the City of Guelph, southwestern Ontario, Canada. This stratigraphic unit makes up part of a stacked carbonate succession that constitutes one of the most economically significant Paleozoic sedimentary rocks in Ontario. The strata assigned to the Eramosa have a complex history of lithostratigraphic study, and the relative age, regional lithostratigraphic relationships, and varied depositional environments of the Eramosa were poorly understood. This research, which combines conodont biostratigraphy and carbonate carbon (δ13Ccarb) isotope stratigraphy to generate a detailed chronostratigraphic framework for the Eramosa Formation in southwestern Ontario, is part of a regional-scale surface and subsurface mapping initiative of the Silurian strata by the Ontario Geological Survey. Dolostone samples from Wiarton and the City of Guelph, Ontario, yielded three biostratigraphically important conodonts: Ozarkodina sagitta rhenana, Kockelella walliseri, and Kockelella ortus ortus. The carbonate carbon (δ13Ccarb) isotope data from the studied intervals record the descending limb of the Sheinwoodian (Ireviken) positive δ13Ccarb isotope excursion, including a distinctive positive shift in δ13Ccarb isotope values typical of records of the descending limb of the excursion in Laurentia and Baltica. Aldridgeodus minimus was also recovered from these conodont faunas and co-occurs with Kockelella walliseri, below the last occurrence of Ozarkodina sagitta rhenana (Lower Kockelella walliseri Zone), suggesting that the range of Aldridgeodus minimus should be extended lower into the Sheinwoodian Stage. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Research indicates that physicians may frequently use pharmacotherapy to treat pediatric insomnia despite minimal safety data and very limited indications. Canadian data on the subject are lacking. This study aimed to determine physicians' views on and prescribing habits for sleep-promoting over-the-counter medication (OTCM) and prescription (RXM) medications for children.Methods: A modified 26-item version of the 'Pediatric Sleep Medication Survey', originally developed by Judith Owens and colleagues, was sent to 100 pediatricians and a random sample of 421 family physicians in Southwestern Ontario, Canada.Results: A total of 67 returned surveys were sufficiently complete for analysis. Sixty-one respondents indicated their specialty (28 pediatricians, 33 family physicians). In a typical 6-month period, 89% and 66% of respondents have recommended OTCM and RXM, respectively, for children with sleep problems. Only 20% have received any formal training on pediatric sleep disorders. The most common circumstances and sleep problems for which OTCM or RXM were recommended were mood disorders, developmental delay and attention deficit hyperactivity disorder (ADHD) (56, 40, and 39%, respectively), and insomnia, bedtime struggles/delayed sleep onset and circadian rhythm disorders (52, 48, and 28%, respectively). A total of 30% recommended OTCM or RXM to otherwise healthy children with sleep problems. Melatonin (73%), OTC antihistamines (41%), antidepressants (37%), and benzodiazepines (29%) were the most commonly recommended OTCM and RXM, respectively.Conclusions: Respondents in our sample frequently use pharmacotherapy to treat pediatric sleep problems; few have received any training in this area. Our findings indicate the need for evidence-based guidelines and regular physician training in the management of pediatric sleep disorders. [ABSTRACT FROM AUTHOR]

Southwestern Ontario has a legacy of unplugged oil and gas wells drilled in the late 1800s and early 1900s before the advent of government regulatory controls. A number of these wells exhibit artesian flow of salty and/or sulphurous water at the surface, creating a liability to landowners and a possible threat to potable groundwater aquifers and the surface environment. Cost-effective plugging of these wells is hindered by incomplete drilling records regarding well depths, well construction, and geologic information on the sources of the leaking fluids. This study seeks to fill this knowledge gap by characterizing distinct geochemical ‘fingerprints’ for each of the major bedrock water-producing zones that may be the possible sources of the leaking fluids. To this end, over 130 groundwater samples were collected and analyzed for a broad suite of isotopic parameters ( δ 18 O, δ 2 H, δ 34 S SO4 , δ 18 O SO4 , δ 13 C DIC , 87 Sr/ 86 Sr, δ 37 Cl and δ 81 Br), and this dataset was combined with available data from previous studies in the area. A Bayesian mixing model, SIAR, was applied to these data to develop a statistical tool for identifying the probable source(s) of leaking fluids. Several hypothetical samples and one real-world example are presented here to demonstrate the model’s performance. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Research has shown the positive associations of family meals and diet quality. However, little is known about how other meals/snacks may be associated with family meals. Objective: The purpose was to determine the associations among the frequency and calorie consumption of meals/snacks and family dinners. Design: Cross-sectional. Data were collected using Web-based Eating Behaviour Questionnaire (WEB-Q) , including a 24-h diet recall for breakfast, morning snack, lunch, afternoon snack, dinner, and evening snack. Measured height and weight were used to determine body weight status (BMI). Participants/setting: Participants included 1068 grade 7 students (52% males) from 26 schools in Windsor Essex County, Ontario, Canada. Main outcome measures: Meal, snack, and total daily caloric intake; meal and snack frequency; with whom dinner was consumed, and weekly family dinner frequency. Statistical analyses performed: Exploratory one-way ANOVAs and chi-square tests; nominal and ordinal logistic regression. Results: Ninety-three percent of participants consumed dinner with family members on the night prior to the survey and 77% reported usually consuming dinner/supper with at least one parent on six to seven nights/week. Those who had dinner with family members consumed 4.88 (SD 1.1) meals/snacks per day compared with 4.40 (SD 1.3) and 4.40 (SD 1.3) times/day for consuming dinner alone or with friends, respectively ( p  = 0.006). On the day prior to the survey, participants were less likely to consume a family meal if they consumed a lower number of meals and snacks per day (OR = 0.69 (95% CI: 0.55, 0.87), p  < 0.001). Similarly, participants were less likely to consume regular family meals if they consumed a lower number of meals and snacks per day (OR = 0.84 (95% CI: 0.74, 0.96), p  = 0.009). Conclusions: While specific meals and snacks were not associated with family dinner, overall eating frequency was positively associated with family meals. [ABSTRACT FROM AUTHOR]

Natural gas reservoirs in organic-rich shales in the Appalachian and Michigan basins in the United States are currently being produced via hydraulic fracturing. Stratigraphically-equivalent shales occur in the Canadian portion of the basins in southwestern Ontario with anecdotal evidence of gas shows, yet there has been no commercial shale gas production to date. To provide baseline data in the case of future environmental issues related to hydraulic fracturing and shale gas production, such as leakage of natural gas, saline water, and/or hydraulic fracturing fluids, and to evaluate hydrogeochemical controls on natural gas accumulations in shallow groundwater in general, this study investigates the origin and distribution of natural gas and brine in shallow aquifers across southwestern Ontario. An extensive geochemical database of major ion and trace metal chemistry and methane concentrations of 1010 groundwater samples from shallow, domestic wells in bedrock and overburden aquifers throughout southwestern Ontario was utilized. In addition, select wells ( n = 36) were resampled for detailed dissolved gas composition, δ 13 C of CH 4 , C 2 , C 3 , and CO 2 , and δD of CH 4 . Dissolved gases in groundwater from bedrock and overburden wells were composed primarily of CH 4 (29.7–98.6 mol% of total gas volume), N 2 (0.8–66.2 mol%), Ar + O 2 (0.2–3.4 mol%), and CO 2 (0–1.2 mol%). Ethane was detected, but only in low concentrations (<0.041 mol%), and no other higher chain hydrocarbons were present, except for one well in overburden overlying the Dundee Formation, which contained 0.81 mol% ethane and 0.21 mol% propane. The highest methane concentrations (30 to >100 in situ % saturation) were found in bedrock wells completed in the Upper Devonian Kettle Point Formation, Middle Devonian Hamilton Group and Dundee Formation, and in surficial aquifers overlying these organic-rich shale-bearing formations, indicating that bedrock geology is the primary control on methane occurrences. A few ( n = 40) samples showed Na–Cl–Br evidence of brine mixing with dilute groundwater, however only one of these samples contained high (>60 in situ % saturation) CH 4 . The relatively low δ 13 C values of CH 4 (−89.9‰ to −57.3‰), covariance of δD values of CH 4 and H 2 O, positive correlation between δ 13 C values of CH 4 and CO 2 , and lack of higher chain hydrocarbons (C 3+ ) in all but one dissolved gas sample indicates that the methane in groundwater throughout the study area is primarily microbial in origin. The presence or absence of alternative electron acceptors (e.g. dissolved oxygen, Fe, NO 3 , SO 4 ), in addition to organic substrates, controls the occurrence of microbial CH 4 in shallow aquifers. Microbial methane has likely been accumulating in the study area, since at least the Late Pleistocene to the present, as indicated by the co-variance and range of δD values of CH 4 (−314‰ to −263‰) and associated groundwater (−19‰ to −6‰ δD-H 2 O). [ABSTRACT FROM AUTHOR]

The acorn weevil, Curculio glandium, is a widespread predator of acorns in eastern North America that overwinters in the soil as a larva. It is possible that low temperatures limit its northern geographic range, so we determined the cold tolerance strategy, seasonal variation in cold tolerance, and explored the physiological plasticity of overwintering larvae. Weevil larvae were collected from acorns of red and bur oak from Pelee Island, southwestern Ontario in fall 2010 and 2011. C. glandium larvae are freeze avoidant and larvae collected from bur oak acorns had lower supercooling points (SCPs: -7.6±0.36 °C, LT50: -7.2 °C) than those collected from red oak acorns (SCPs: -6.1±0.40 °C, LT50: -6.1 °C). In the winter of 2010-2011, SCPs and water content decreased, however these changes did not occur in 2011-2012, when winter soil temperatures fluctuated greatly in the absence of the buffering effect of snow. To examine whether larvae utilize cryoprotective dehydration, larvae from red oak acorns were exposed to -5 °C in the presence of ice for seven days. These conditions decreased the SCP without affecting water content, suggesting that SCP and water content are not directly coupled. Finally, long-term acclimation at 0 °C for six weeks slightly increased cold tolerance but also did not affect water content. Thus, although larval diet affects cold tolerance, there is limited plasticity after other treatments. The soil temperatures we observed were not close to lethal limits, although we speculate that soil temperatures in northerly habitats, or in years of reduced snow cover, has the potential to cause mortality in the field. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this research is to assess the food safety awareness and perceptions of artisan cheese makers using semi-structured interviews based on the Risk Analysis Framework. Seventeen in-depth interviews were conducted with managers and workers from 11 different cheese companies. The interviews were audio taped and transcribed verbatim. Common themes in the interview transcripts were identified. Listeria monocytogenes was perceived to be the most concerning biological hazard due to its potential impact on human health and business. Overall, the impact on food safety from chemical and physical hazards was perceived to be limited, and to be more of an occupational health and safety risk. More than half of the respondents supported the production of safe raw milk cheese, although they acknowledged the inherent bacterial hazards associated with it. Current food safety management systems such as HACCP were perceived to be excessively complicated due to the over-emphasis on documentation and the need for additional resources. Cheese safety education was valued, but participation was limited due to the lack of financial resources and available programs in the region. [Copyright &y& Elsevier]

Abstract: Sources of fecal water pollution were assessed in the Grand River and two of its tributaries (Ontario, Canada) using total and host-specific (human and bovine) Bacteroidales genetic markers in conjunction with reference information, such as land use and weather. In-stream levels of the markers and culturable Escherichia coli were also monitored during multiple rain events to gain information on fecal loadings to catchment from diffuse sources. Elevated human-specific marker levels were accurately identified in river water impacted by a municipal wastewater treatment plant (WWTP) effluent and at a downstream site in the Grand River. In contrast, the bovine-specific marker showed high levels of cattle fecal pollution in two tributaries, both of which are characterized as intensely farmed areas. The bovine-specific Bacteroidales marker increased with rainfall in the agricultural tributaries, indicating enhanced loading of cattle-derived fecal pollutants to river from non-point sources following rain events. However, rain-triggered fecal loading was not substantiated in urban settings, indicating continuous inputs of human-originated fecal pollutants from point sources, such as WWTP effluent. This study demonstrated that the Bacteroidales source tracking assays, in combination with land use information and hydrological data, may provide additional insight into the spatial and temporal distribution of source-specific fecal contamination in streams impacted by varying land uses. Using the approach described in this study may help to characterize impacted water sources and to design targeted land use management plans in other watersheds in the future. [Copyright &y& Elsevier]

Highlights: [•] Hydraulic testing of Silurian and Ordovician sediments – eastern Michigan Basin. [•] Test equipment, methods and analysis specifically adapted for low-permeability rock. [•] Parameter perturbation analysis method allows quantification of uncertainty. [•] K values range from 4E−14 to 4E−8m/s (Silurian) and 2E−16 to 2E−10 m/s (Ordovician). [•] Scaled Ordovician K values consistent with laboratory and natural analog estimates. [Copyright &y& Elsevier]

A recent magnetometer survey from the Late Archaic Davidson Site (AhHk-54) demonstrates the potential of this technique in understanding hunter-gatherer occupations in the Great Lakes Region, and contributes to our understanding of temporal change in the spatial use of the site. Davidson was investigated to test the long held, but little substantiated notion that the Late Archaic represents a time of reduced seulement mobility. Hundreds of features, including storage pits, earth ovens, hearths and the remains of some of the oldest known houses in the Great Lakes region were iden-tified using the magnetometer and indicate that the site is much larger and more complex than previously believed. Ground-truthing of these results through excavation and coring, combined with repeated field-walking of the site to map artifact distributions, allows us to document more fully the extent of intact deposits, the site setting at the time of the occupation and changes in site function and use from the Broad Point to Small Point (Terminal) Archaic. Our findings indicate that more widespread use of geophysical survey techniques on Canadian archaeological sites has the potential to contribute not only to a deeper understanding of the archaeological record, but also to the development of archaeogeophysics from its traditional role in site prospection to more problem-based, theoretically informed applications. [ABSTRACT FROM AUTHOR]

Abstract: In this study we report on the economic evaluation of a participatory ergonomics process undertaken at a clothing manufacturer in Southwestern Ontario, Canada that employs approximately 300 workers. We undertake a cost-benefit analysis from the company perspective. Intervention costs amounted to $65,787 and intervention benefits $360,614 (2011 Canadian dollars). The net present value was $294,827, suggesting that the intervention was worth undertaking based on the costs and consequences over the measurement period spanning more than four years. Based on these costs and benefits, the benefit-to-cost ratio is 5.5. Overall, the findings from this study suggest that participatory ergonomics interventions can be cost beneficial from the company perspective. Even though the changes were typically low-cost and low-tech interventions implemented by the plant mechanics and maintenance personnel, benefits were realized on both the health and financial fronts. [Copyright &y& Elsevier]

Abstract: Middle Ordovician Trenton Group carbonates are fractured and extensively dolomitized along the axis of the Algonquin Arch in southwestern Ontario. Hydrocarbon reservoirs formed where these dolomitized fracture zones penetrate otherwise impermeable host limestones. Three different types of dolomite (D1, D2 and D3) are distinguished. Petrographic characteristics and δ18O values indicate that D1 formed during early diagenesis from Middle Ordovician seawater and recrystallized during progressive burial, whereas fracture-related, replacive matrix dolomite (D2) formed by hydrothermal fluids (68–99 °C). Late-stage saddle dolomite (D3) and calcite (C3) cements occlude fractures. Based on petrographic, fluid inclusion, and stable isotope data, D3 dolomite and C3 calcite formed from warm (68–144 °C), saline (22–24 wt. % NaCl + CaCl2) hydrothermal fluids. The least radiogenic 87Sr/86Sr values (0.70830–0.70842) of D2 are consistent with estimated values of Devonian and Silurian seawater, whereas the slightly enriched 87Sr/86Sr ratios of D2 and D3 (0.70902–0.70918) suggest their precipitation from fluids similar in composition to oil field brines. Rare earth element (REE) results of D2, D3, and C3 indicate enrichment in REEs content of these mineral phases relative to undolomitized host rock. The similarity in the average REEs pattern of D2, D3, and C3 and the overlying Blue Mountain shale and basement rocks suggest progressive water/rock interaction. Magnesium required for dolomite precipitation was supplied by Mg-rich seawater-derived (Silurian and/or Devonian) saline waters from dissolution of Silurian evaporites which descended along faults and fractures, to reservoir depths at the center of the basin while being heated. Hot basinal brines migrated laterally through basal sandstones and ascended into the network of faults and fractures and precipitated fracture-related dolomite. The abundance of fracture-related dolomite in the periphery of Michigan Basin in southwestern Ontario suggests that dolomitizing fluids originated from the Michigan Basin rather than Appalachian Basin. [Copyright &y& Elsevier]

Data collected in 14 southwestern Ontario counties and regional municipalities demonstrated that the development of community food initiatives is not happening uniformly across the region. Rather, some areas (notably Wellington and Norfolk counties and Waterloo Region) are home to a wide variety of projects that, in many cases, are woven together into networks and enjoy relatively broad-based support from local communities. In contrast, in other places (for example, Dufferin, Elgin, and Kent counties), efforts to foster the development of alternative food systems are fewer and farther between, more fledgling in nature, and appear subject to more constraints than their counterparts in neighbouring parts of the region. This paper will explore the uneven geography of community food projects in southwestern Ontario, and discuss how the presence of social capital structured around an alternative food system vision can help expand the realm of possibility for such initiatives. [ABSTRACT FROM AUTHOR]

Monarch butterflies (Danaus plexippus) breeding in eastern North America are famous for their annual fall migration to their overwintering grounds in Mexico. However, the mechanisms they use to successfully reach these sites remain poorly understood. Here, we test whether monarchs are true navigators who can determine their location relative to their final destination using both a "compass" and a "map". Using flight simulators, we recorded the orientation of wild-caught monarchs in southwestern Ontario and found that individuals generally flew in a southwest direction toward the wintering grounds. When displaced 2,500 km to the west, the same individuals continued to fly in a general southwest direction, suggesting that monarchs use a simple vector-navigation strategy (i.e., use a specific compass bearing without compensating for displacement). Using over 5 decades of field data, we also show that the directional concentration and the angular SD of recoveries from tagged monarchs largely conformed to two mathematical models describing the directional distribution of migrants expected under a vector-navigation strategy. A third analysis of tagged recoveries shows that the increasing directionality of migration from north to south is largely because of the presence of geographic barriers that guide individuals toward overwintering sites. Our work suggests that monarchs breeding in eastern North America likely combine simple orientation mechanisms with geographic features that funnel them toward Mexican overwintering sites, a remarkable achievement considering that these butterflies weigh less than a gram and travel thousands of kilometers to a site they have never seen. [ABSTRACT FROM AUTHOR]

Three distinctly different undisturbed mature forested sites at the northern limits of the Carolinian forest system in Lambton County, Ontario, were examined to test the hypothesis that the abundance of each order of soil invertebrates captured is dependent on a unique set of soil properties, seasonal changes, and climate variations. Sixteen independent variables were recorded over five consecutive years. With the exception of rainfall, air temperature, and soil temperature, means of the measured variables differed significantly (P < 0.05) among soils. Twenty-eight taxa of invertebrates were captured, of which Acari, Collembola, and Nematoda were most abundant. Only the mean of total abundance and the mean abundance of Acari, Nematoda, and Haplotaxida differed significantly (P < 0.05) among soils. Haplotaxida was the only taxon in all three soils found to be influenced significantly (P < 0.05) by seasonal variation. The usual mid-summer minimum in the abundance of Haplotaxida was latest and most clearly defined in the clay soil and earliest and least clearly defined in the sand soil. Regression analysis showed that each site is suffi-ciently separated in the factor space observed that the abundance of each invertebrate taxon is dependent on different combinations of local variables. The hypothesis was rejected. [ABSTRACT FROM AUTHOR]

Recent literature, supported by a survey of secondary school teachers in southwestern Ontario, Canada, indicates that preservice teacher education does not adequately prepare graduating teacher candidates to thrive in a profession that is ironically, driven by change. Attempts at reform have focused on the basic aspects of the typical preservice program: foundations, curriculum methods and field experience. The results have been decidedly discouraging. Positive improvement will hinge both on a recognition by teacher-education institutions, of the inevitable compromise between short-term necessity and long-term vision, and on their willingness to implement, carefully and constructively, promising innovations such as action research and centers of pedagogy.

Abstract: A forensic modeling study examines the potential causes of gas and water venting observed during the excavation of a landfill in a 40m thick clayey till deposit in southwestern Ontario, Canada. The clayey till is known to be underlain by permeable, natural gas bearing, rock and gas has been diffusing through the clayey deposit over about the last 13,000–15,000years. Attention is focused on 2D modeling of hydrofracturing as well as gassy soil behavior. The model examines the predicted location of venting with and without the presence of gassy sand lenses and a discontinuous layer of basal till between the bedrock and the low permeability till. The modeling shows that hydrofracturing alone can explain the occurrence and location of the observed venting in one of the sub-cells. In the other sub-cell, hydrofracturing explains the occurrence but not the location of the observed venting or the presence of the sand in the venting water at this location. Modeling of appropriately placed gassy sand lenses is shown to explain the occurrence and location of the observed venting as well as the presence of both waters with different geochemistry from the bedrock and the till in the venting waters. [Copyright &y& Elsevier]

Abstract: The emerald ash borer (EAB), Agrilus planipennis (Coleoptera: Buprestidae), is an invasive wood boring beetle that is decimating North America’s ash trees (Fraxinus spp.). To find effective and safe indigenous biocontrol agents to manage EAB, we conducted a survey in 2008–2009 of entomopathogenic fungi (EPF) infecting EAB in five outbreak sites in southwestern Ontario, Canada. A total of 78 Beauveria spp. isolates were retrieved from dead and mycosed EAB cadavers residing in the phloem tissues of dead ash barks, larval frass extracted from feeding galleries under the bark of dead trees. Molecular characterization using sequences of the ITS, 5′ end of EF1-α and intergenic Bloc region fragments revealed that Beauveria bassiana and Beauveria pseudobassiana were commonly associated with EAB in the sampled sites. Based on phylogenetic analysis inferred from ITS sequences, 17 of these isolates clustered with B. bassiana, which further grouped into three different sub-clades. However, the combined EF1-α and Bloc sequences detected five genotypes among the three sub-clades. The remaining 61 isolates clustered with B. pseudobassiana, which had identical ITS sequences but were further subdivided into two genotypes by variation in the EF1-α and Bloc regions. Initial virulence screening against EAB adults of 23 isolates representing the different clades yielded 8 that produced more than 90% mortality in a single concentration assay. These isolates differed in virulence based on LC50 values estimated from multiple concentration bioassay and based on mean survival times at a conidia concentration of 2×106 conidia/ml. B. bassiana isolate L49-1AA was significantly more virulent and produced more conidia on EAB cadavers compared to the other indigenous isolates and the commercial strain B. bassiana GHA suggesting that L49-1AA may have potential as a microbiological control agent against EAB. [Copyright &y& Elsevier]

Through the use of case-control analyses and quantitative microbial risk assessment (QMRA), relative risks of transmission of cryptosporidiosis have been evaluated (recreational water exposure vs. drinking water consumption) for a Canadian community with higher than national rates of cryptosporidiosis. A QMRA was developed to assess the risk of Cryptosporidium infection through the consumption of municipally treated drinking water. Simulations were based on site-specific surface water contamination levels and drinking water treatment log10 reduction capacity for Cryptosporidium. Results suggested that the risk of Cryptosporidium infection via drinking water in the study community, assuming routine operation of the water treatment plant, was negligible (6 infections per 1013 persons per day-5th percentile: 2 infections per 1015 persons per day; 95th percentile: 3 infections per 1012 persons per day). The risk is essentially nonexistent during optimized, routine treatment operations. The study community achieves between 7 and 9 log10 Cryptosporidium oocyst reduction through routine water treatment processes. Although these results do not preclude the need for constant vigilance by both water treatment and public health professionals in this community, they suggest that the cause of higher rates of cryptosporidiosis are more likely due to recreational water contact, or perhaps direct animal contact. QMRA can be successfully applied at the community level to identify data gaps, rank relative public health risks, and forecast future risk scenarios. It is most useful when performed in a collaborative way with local stakeholders, from beginning to end of the risk analysis paradigm. [ABSTRACT FROM AUTHOR]

Abstract: Ridge tillage (RT) creates a distinctly different soil environment relative to no-tillage (NT) and mouldboard plow tillage (MP), which may in turn affect soil properties. In this study, the impacts of long-term (29 years) RT on soil organic carbon (SOC), water content, bulk density and penetration resistance were compared with NT and MP tillage on a clay loam soil under a corn (Zea mays L.)–soybean (Glycine max L. Merr.) rotation. The ridges in RT were formed at 76-cm spacing and corn was planted in the center of the ridges whereas soybean was planted in the shoulders of the ridges at 38-cm spacing. Soil samples were collected from the ridge crest (i.e. corn row), from the two ridge shoulder positions and from the interrow (furrow) positions of the ridges to evaluate both the spatial and profile distributions of the selected soil properties under RT relative to NT and MP. Ridge tillage produced low SOC in the interrows, high SOC in the crests and medium SOC in the shoulders relative to MP and NT. Soil water content was higher in the interrows than in the crests of the ridges, while soil penetration resistance followed the reverse trend. No-tillage resulted in a distinct SOC stratification with significantly higher SOC in surface soil and slightly lower SOC in subsurface soil while a uniform distribution of SOC was observed in the plow layer of MP soil. Hence, RT produced different SOC, water content, bulk density and penetration resistance distributions than NT and MP. Twenty-nine years of RT management resulted in improved soil physical conditions in the plow layer for crop root growth relative to NT and greater SOC stocks within the plow layer compared to MP. [Copyright &y& Elsevier]

Meteorological observations from the BAQS-Met field experiment during the summer months of 2007 were integrated and manually analyzed in order to identify and characterize lake breezes in the southern Great Lakes region of North America, and assess their potential impact on air quality. Lake breezes occurred frequently, with one or more lake breezes identified on 90% of study days. They affected all parts of the study region, including southwestern Ontario and nearby portions of southeast Lower Michigan and northern Ohio, with lake-breeze fronts occasionally penetrating from 100 km to over 200 km inland. Occurrence rates and penetration distances were found to be higher than previously reported in the literature. This comprehensive depiction of observed lake breezes allows an improved understanding of their influence on the transport, dispersion, and production of pollutants in this region. The observational analyses were compared with output from subsequent runs of a high-resolution numerical weather prediction model. The model accurately predicted lake breeze occurrence and type in a variety of synoptic wind regimes, but selected cases showed substantial differences in the detailed timing and location of lake-breeze fronts, and with the initiation of deep moist convection. Knowledge of such strengths and weaknesses aids in the interpretation of results from air quality models driven by this meteorological model. [ABSTRACT FROM AUTHOR]

Abstract: Pyroxasulfone is a new herbicide being considered for registration in sweet maize in Canada; however, there is still little information on the doses required to provide 90% control of annual grass and broadleaved weeds found in southwestern Ontario. The objective of this study was to determine pyroxasulfone doses that would provide at least 90% control of several economically important weeds, without impacting final sweet maize yield by more than 5% in comparison to a weed-free control. Six field trials were conducted over a two-year period (2007 and 2008) at three Ontario locations to evaluate the effectiveness of pyroxasulfone at doses ranging from 31.25 to 1000 g a.i. ha−1. The doses required to reduce weed biomass by at least 90% (I90) varied by weed species. Doses of 93, 499, and 111 g a.i. ha−1 were required to reduce the biomass by 90% of redroot pigweed, common lambsquarters and green foxtail, respectively. There was greater than 95% control of velvetleaf, large crabgrass and barnyardgrass with 31.25 g a.i. ha−1, the lowest dose tested. Sweet maize yield could not be consistently maintained within 5% of the weed-free control. There are several factors that may have contributed to the reduced yield, including soil texture effects, competition as a result of poor common lambsquarters control, and hybrid sensitivity. These results show that biologically effective weed control with pyroxasulfone may be achieved at lower than proposed doses for several weed species; it remains unclear if this is economically sustainable due to the potential impacts on yield. [Copyright &y& Elsevier]

Abstract: High levels of deer browsing can prevent canopy tree regeneration, but little is known about changes to forest size-structure following long-term deer herd reductions. We monitored changes in forest stand structure and composition in southwestern Ontario, Canada, over 28-years using permanent plots. Our study site was the largest remaining tract of Carolinian (deciduous) forest in Canada (11km2), a habitat type that contains up to a fifth of Canada’s species at risk and is under intense anthropogenic pressures. We recorded declines in all tree size classes between 1981 and 1996, during which densities of white-tailed deer (Odocoileus virginianus) reached a peak of 55 deer km−2. Despite significant and sustained deer herd reductions between 1996 and 2009, which reduced deer densities to 7 deer km−2, there was limited recruitment of small trees and declines in basal area of tree species that were sensitive to deer browsing. Our results suggest that recovery from herbivory is a protracted process during which canopy tree regeneration may continue to decline despite a reduction in browsing pressure due to deer culling. Large declines in canopy-tree densities in Carolinian forests may lead to forest size-structures and herbaceous plant communities that resemble rare oak savanna habitat, creating difficult decisions for conservation managers aiming to protect rare and endangered species within native ecosystems. We recommend that managers protect Carolinian forest stands and encourage canopy tree regeneration by increasing seed sources of native trees. While deer control is essential in reducing forest damage, our results highlight the need to explore other forms of active management to expedite otherwise slow increases in tree density. [ABSTRACT FROM AUTHOR]

Abstract: A field experiment was completed at a fractured dolomite aquifer in southwestern Ontario, Canada, to assess the delivery of supersaturated dissolved oxygen (supersaturated with respect to ambient conditions) for enhanced bioremediation of petroleum hydrocarbons in groundwater. The injection lasted for 1.5h using iTi''s gPro® oxygen injection technology at pressures of up to 450kPa and at concentrations of up to 34mg O2/L. A three-dimensional numerical model for advective–dispersive transport of dissolved oxygen within a discretely-fractured porous medium was calibrated to the observed field conditions under a conservative (no-consumption) scenario. The simulation demonstrated that oxygen rapidly filled the local intersecting fractures as well as the porous matrix surrounding the injection well. Following injection, the local fractures were rapidly flushed by the natural groundwater flow system but slow back-diffusion ensured a relatively longer residence time in the matrix. A sensitivity analysis showed significant changes in behaviour with varying fracture apertures and hydraulic gradients. Applying the calibrated model to a 7-day continuous injection scenario showed oxygen residence times (at the 3mg/L limit), within a radius of 2–4m from the injection well, of up to 100days. This study has demonstrated that supersaturated dissolved oxygen can be effectively delivered to this type of a fractured and porous bedrock system at concentrations and residence times potentially sufficient for enhanced aerobic biodegradation. [Copyright &y& Elsevier]

The article presents a study which investigates the soil types and antecedent soil moisture conditions in south-western Ontario. The study used simulation model to conduct the investigation and performed a frequency analysis which revealed the distributions of soil moisture conditions and the effect of textured soil particles. Equations were formed to estimate the antecedent soil moisture condition average based on soil characteristics.

What are the life experiences of farm children in rural southwestern Ontario? Within the rural sociological literature, little research has been undertaken on the geographies of Canadian children in rural settings. Play, leisure, work and future aspirations are important to their lives. However, little is known about these issues and children's use of space and place on the farm. This study focuses on these issues from the point of view of the child and examines how gender, age and socialization processes work together with agrarianism to frame the lifeworlds of these children. In general, these children do not aspire to farm in the future, but are interested in future residence in the country. They value the way of life to be found in farming but some experience loneliness on the farm. For farm children, space and farm animals act as comfort in their lives and make for unique experiences. [ABSTRACT FROM AUTHOR]