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Evaluating the impacts of farming systems on biodiversity is increasingly important given the need to stem biodiversity loss, decrease fossil fuel dependency, and maintain ecosystem services benefiting farmers. We recorded woody and herbaceous plant species diversity, composition, and abundance in 43 wetland‐adjacent prairie remnants beside crop fields managed using conventional, minimum tillage, organic, or perennial cover (wildlife‐friendly) land management in the Prairie Pothole Region. We used a hierarchical framework to estimate diversity at regional and local scales (gamma, alpha), and how these are related through species turnover (beta diversity). We tested the expectation that gamma richness/evenness and beta diversity of all plants would be higher in remnants adjacent to perennial cover and organic fields than in conventional and minimum tillage fields. We expected the same findings for plants providing ecosystem services (bee‐pollinated species) and disservices (introduced species). We predicted similar relative effects of land management on alpha diversity, but with the expectation that the benefits of organic farming would decrease with increasing grassland in surrounding landscapes. Gamma richness and evenness of all plants were highest for perennial cover, followed by minimum tillage, organic, and conventional sites. Bee‐pollinated species followed a similar pattern for richness, but for evenness organic farming came second, after perennial cover sites, followed by minimum tillage and conventional. For introduced species, organic sites had the highest gamma richness and evenness. Grassland amount moderated the effect of land management type on all plants and bee‐pollinated plant richness, but not as expected. The richness of organic sites increased with the amount of grassland in the surrounding landscape. Conversely, for conventional sites, richness increased as the amount of grassland in the landscape declined. Our results are consistent with the expectation that adopting wildlife‐friendly land management practices can benefit biodiversity at regional and local scales, in particular the use of perennial cover to benefit plant diversity at regional scales. At more local extents, organic farming increased plant richness, but only when sufficient grassland was available in the surrounding landscape; organic farms also had the highest beta diversity for all plants and bee‐pollinated plants. Maintaining native cover in agroecosystems, in addition to low‐intensity farming practices, could sustain plant biodiversity and facilitate important ecosystem services. [ABSTRACT FROM AUTHOR]

Maintaining and improving soil health (SH) is essential for the long-term sustainability and productivity of agriculture, notably in the face of climate change. This study addressed the challenge of selecting appropriate soil indicators, scoring methods, and indexing approaches for SH evaluation under no-till crop rotations. This study aimed to develop minimum datasets (MDS) and assess SH in six crop rotations (denoted as conventional, diversified, high-risk and high-reward, market-driven, pulse-oilseed intensified, and soil health-enhanced rotations) at three sites on the Canadian prairies. Fourteen soil indicators in the total dataset (TDS) were examined, encompassing both chemical (0-7.5 cm depth) and physical (5-10 cm depth) properties. Principal component analysis (PCA) identified MDSs from the TDS. Two scoring [linear (L) and non-linear (NL)] and two SH indexing approaches [additive (A) and weighted additive (WA)] were used to calculate the SH index (SHI). One-way ANOVA evaluated the SHI among crop rotations. The PCA revealed variations in the number of indicators in the MDS across sites, with soil organic carbon, bulk density, macroporosity, and plant-available water capacity as the common indicators for MDS across sites. Other indicators such as particulate organic matter carbon, aggregate stability, field capacity, and microporosity were found to be important, depending on the site. The non-linear weighted additive SH indexing (SHI.NLWA) proved to be the most sensitive and effective for differentiating among crop rotations in the short-term across study sites (R 2  = 0.89-0.94, P < 0.05). Crop rotations significantly influenced SHI, with the diversified and high-risk and high-reward rotations having the highest SHI at Lethbridge and Scott, respectively. Overall, the diversified rotation at Lethbridge and Swift Current, along with the high-risk and high-reward rotation at Scott, exhibited better soil function than other rotations. Monitoring SHI over time and selecting crop rotations that improve SH can collectively enhance soil functions and agroecosystem productivity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Crown Copyright © 2024. Published by Elsevier B.V. All rights reserved.)

Canola/oilseed rape (Brassica napus L.) production in Canada has increased to become a foundational crop in the Canadian Prairies and an important economic driver of this region. The increase in seeded area, and by association its reduction in-crop rotation frequency, has made it easier for pests to overcome current recommended agronomic management practices. The Canola Council of Canada has been successful in involving the entire commodity value chain in promoting and strengthening the Canadian canola industry; however, because of this production increase it is critically important to understand, evaluate and mitigate the potential risks of canola yield losses to current and potential pests. This Perspective provides an overview of what are currently the most damaging insects, pathogens and weeds to canola in the Canadian Prairies, potential future threats and opportunities farmers, agronomists and researchers can take to minimize these risks. © 2023 Society of Chemical Industry., (© 2023 Society of Chemical Industry.)

Aquatic invertebrates provide important ecosystem services, including decomposition and nutrient cycling, and provide nutrition for birds, fish, amphibians, and bats. Thus, the effects of agricultural land management practices on aquatic invertebrates are relevant to farmers, wildlife biologists, and policymakers. Here, we used data on aquatic invertebrates (159 taxa, 73 to species, 75 to genus/family) collected in 40 wetlands in the Canadian prairies to test for direct and indirect relationships among land management types (perennial cover, organic, minimum tillage, conventional), landscape structure (cropland and wetland cover within the surrounding landscape), and water quality (total nutrient levels, turbidity) on species richness of invertebrates using structural equation modelling. Additionally, we assessed variation in community composition within and among wetlands in different land use management types using a direct gradient analysis and variance partitioning. The direct effects of land management type were not supported but we found strong supportive evidence that effects of land management on richness were significantly mediated through cropland cover, nutrient levels, and turbidity. After controlling for these indirect effects, aquatic invertebrate richness decreased along a gradient from the lowest to the highest farming intensity, i.e., richness decreased from perennial cover sites to organic to minimum tillage to conventional sites. Support was also found for negative effects of nutrient levels and turbidity on richness. We did not find significant support for differences in gamma diversity or a simple test (homogeneity of multivariate dispersions) of differences in turnover among land management types; however, land management had a significant effect in distance-based redundancy analysis. Taken together, these results suggest that focusing conservation efforts on reducing cropland erosion and nutrient inputs to wetlands and creating more permanent cover may be effective strategies for conserving richness of aquatic invertebrates in agricultural landscapes in this region., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Kirk et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Soil microbial communities play a vital role in the biogeochemical cycling and ecological functioning of grassland, but may be affected by common land uses such as cattle grazing. Changes in microbial diversity and network complexity can affect key ecosystem functions such as nutrient cycling. However, it is not well known how microbial diversity and network complexity respond to grazing in the Northern Great Plains. Consequently, it is important to understand whether variation in grazing management alters the diversity and complexity of grassland microbial communities. We compared the effect of intensive adaptive multi-paddock (AMP) grazing and conventional grazing practices on soil microbial communities using 16S/ITS amplicon sequencing. Samples were collected from grasslands in 13 AMP ranches and 13 neighboring, conventional ranches located across the Canadian prairies. We found that AMP grazing increased fungal diversity and evenness, and led to more complex microbial associations. Acidobacteria, Actinobacteria, Gemmatimonadetes, and Bacteroidetes were keystone taxa associated with AMP grazing, while Actinobacteria, Acidobacteria, Proteobacteria, and Armatimonadetes were keystone taxa under conventional grazing. Besides overall grazing treatment effects, specific grazing metrics like cattle stocking rate and rest-to-grazing ratio affected microbial richness and diversity. Bacterial and fungal richness increased with elevated stocking rate, and fungal richness and diversity increased directly with the rest-to-grazing ratio. These results suggest that AMP grazing may improve ecosystem by enhancing fungal diversity and increasing microbial network complexity and connectivity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

A comparison was made of the supercooling points (SCPs) of questing Dermacentor variabilis adults from two populations located ca. 800 km apart on the Canadian prairies. This is also the first study to examine whether there are seasonal fluctuations in the SCP of questing D. variabilis adults. The SCPs of adult ticks from Lizard Lake Community Pasture, a recently established population in west-central Saskatchewan, varied over spring and summer, with the median SCP warming over time. In addition, the SCPs of ticks from Lizard Lake Community Pasture were significantly higher than those of adult ticks collected from Sandy Hook in Manitoba, a population that has been established for decades. The off-host survival of adults from Sandy Hook between summer and spring has been shown previously to be significantly greater than that of adults from Lizard Lake Community Pasture. The findings of the present study suggest that there may be geographical variation in the SCPs of D. variabilis adults which may be associated with differences in overwinter survival. The relatively low SCPs of questing D. variabilis adults, and the ability of some adults to survive off-host during winter, may be factors contributing to the range expansion of this tick species in Canada., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Anthropogenic development may influence the choices animals make and their resulting reproductive success and survival. If such choices are maladaptive, the impact of anthropogenic change can be catastrophic to small or declining populations. Over the past century, Canada's prairie landscapes have been altered dramatically, with over two‐thirds of its native grasslands now having been converted to cropland. The decline of the endangered Burrowing Owl Athene cunicularia population is assumed to have resulted from this landscape change, yet no causal link has been demonstrated. One hypothesis to explain this population decline is that owls get caught in an ecological trap, whereby they prefer to establish nests at the start of each breeding season in landscapes that later confer lower reproductive success. Agricultural landscapes represent a plausible potential ecological trap because the short and sparse vegetation in annual crops (seeded each spring) is predicted to be attractive nesting/foraging habitat for Burrowing Owls when they arrive from northward migration, yet crops become substantially taller and denser over the growing season so prey are predicted to become less accessible by the time broods have hatched. We tested this ecological trap hypothesis in a 3‐year study, involving 379 Burrowing Owl pairs, across the agricultural landscapes of southern Alberta and Saskatchewan. In support of the hypothesis, Burrowing Owls did prefer to settle in breeding home‐ranges that contained a higher proportion of cropland, and their prey‐delivery rates during brood‐rearing were lower at nests with a higher proportion of cropland growing in the surrounding landscape. However, in contradiction to a key prediction, the number of fledglings produced (range = 0–9) was higher, not lower, for pairs with more actively growing cropland in their landscapes. Therefore, the decline of the Burrowing Owl in Canada does not appear to result from cropland forming an ecological trap during the breeding season. We also found a significant positive relationship between the amount of summer fallow within Burrowing Owl home‐ranges and the quantity of vertebrate prey delivered to the nest and the number of juveniles fledged, highlighting the importance of this declining land use in raptor conservation. [ABSTRACT FROM AUTHOR]

The effects of temperature and relative humidity (RH) on female reproductive output, egg development and larval survival were determined for Rocky Mountain wood ticks (Dermacentor andersoni) from a prairie population (Chin Lakes, Alberta, Canada) near the northern distribution limit of this species. The responses of D. andersoni eggs and unfed larvae to different temperature (25 or 32 °C) and RH (35, 55, 75, 85 or 95%) regimes were compared to our previously published data (Diyes et al. 2021) for a northern prairie population of American dog ticks (Dermacentor variabilis). Oviposition by D. andersoni females took 21-30 days at 25 °C and 95% RH compared to 10-21 days for D. variabilis. The number of eggs laid by female ticks was strongly dependent on their engorgement weight, and D. andersoni females produced more eggs than D. variabilis females of an equivalent body weight. Eggs of D. andersoni took less time to develop at 32 °C than 25 °C with ≥ 85% RH, and hatched faster than those of D. variabilis. Larval survival times declined as temperature increased and RH decreased, but D. andersoni survived longer at 32 °C and ≤ 75% RH than D. variabilis. The interspecific differences in responses to the same temperature and humidity regimes indicate that D. andersoni is xerophilic, whereas D. variabilis is hydrophilic. Hence, 'prairie' populations of the Rocky Mountain wood tick occur in the drier grassland ecoregions but are absent in Aspen Parklands Ecoregion which is located to the north and east of the distributional range of D. andersoni., (© 2023. His Majesty in Right of Canada as represented by the Minister of Agriculture and Agri-Food and Chulantha P. Diyes, Neil B. Chilton.)

This study conducted a spatio-temporal analysis of runoff, total suspended sediment, suspended particulate carbon, nitrogen, and phosphorus loadings within the 2.06 km 2 Steppler subwatershed in southern Manitoba of Canada based on 11 years of field monitoring data collected at nine stations. Results showed that the nutrient losses were very small because of the implementation of multiple BMPs in the study area. However, a high spatio-temporal variation of runoff and water quality parameters was found for the nine fields within the subwatershed. The average runoff coefficient was 0.19 at the subwatershed outlet with sediment, suspended particulate carbon, total nitrogen, and total phosphorus losses of 73.8, 6.10, 4.54, and 0.76 kg/ha respectively. Spring snowmelt runoff was about 74.5% of the annual runoff at the subwatershed outlet, while for sediment, suspended particulate carbon, total nitrogen, and total phosphorus, the proportions were 61.1%, 63.6%, 74.9%, and 81.2% respectively during the monitoring period, which suggests that BMPs designed for reducing nutrient loadings from snowmelt runoff would be more effective than BMPs designed for reducing pollutant loading from rainfall storms in the study area. Research findings from this study will benefit the enhancement of current BMPs and the development of new BMPs in the region to minimize soil and nutrient losses from agricultural fields and improve water quality in receiving water bodies., (© 2023. Crown.)

Veterinary antimicrobials (VAs) widely used in intensive livestock production are excreted in livestock manure. Manure is an essential component in agriculture for recycling critical nutrients and improving overall soil health. However, manure application on agricultural lands increases the risk of contaminating the ecosystem with antimicrobials. Antimicrobials in manure-amended soils can affect ecosystem functioning via their negative effect on biogeochemical cycles and increase human exposure. Also, the release of antimicrobials to the broader environment, including that arising because of offsite transport, is linked to the global increase in antibiotic resistance in bacteria. Antibiotic resistance is an emerging global threat to human health, particularly the pathogenic bacteria resistant to the main antimicrobial classes in use. Therefore, there is a need to review current literature to enhance our understanding of the fate of these contaminants across agricultural landscapes. This review focuses on (1) a detailed discussion of sorption mechanisms by exploring the structural attributes of antimicrobials, (2) specific sorption interactions with active adsorbent components in the soil as these comprehensive data are important to identify the sorption strengths of antimicrobials which control their fate in the ecosystem, and (3) the effects of on-farm management practices on VA transport and is focused on manure amendment and tillage practices. The key facts identified in this review are critical to identifying sustainable on-farm management practices to enhance the productivity of arable agricultural lands in Canada and across the globe while minimizing the risk of offsite transport of VAs. Further, the research gaps highlighted in the relevant sections are important to designing future research in Canada and globally under similar to variable land/farm management practices., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Microbial communities are an important component of freshwater biodiversity that is threatened by anthropogenic impacts. Wastewater discharges pose a particular concern by being major sources of anthropogenic contaminants and microorganisms that may influence the composition of natural microbial communities. Nevertheless, the effects of wastewater treatment plant (WWTP) effluents on microbial communities remain largely unexplored. In this study, the effects of wastewater discharges on microbial communities from five different WWTPs in Southern Saskatchewan were investigated using rRNA gene metabarcoding. In parallel, nutrient levels and the presence of environmentally relevant organic pollutants were analyzed. Higher nutrient loads and pollutant concentrations resulted in significant changes in microbial community composition. The greatest changes were observed in Wascana Creek (Regina), which was found to be heavily polluted by wastewater discharges. Several taxa occurred in greater relative abundance in the wastewater-influenced stream segments, indicating anthropogenic pollution and eutrophication, especially taxa belonging to Proteobacteria, Bacteroidota, and Chlorophyta. Strong decreases were measured within the taxa Ciliphora, Diatomea, Dinoflagellata, Nematozoa, Ochrophyta, Protalveolata, and Rotifera. Across all sample types, a significant decline in sulfur bacteria was measured, implying changes in functional biodiversity. In addition, downstream of the Regina WWTP, an increase in cyanotoxins was detected which was correlated with a significant change in cyanobacterial community composition. Overall, these data suggest a causal relationship between anthropogenic pollution and changes in microbial communities, possibly reflecting an impairment of ecosystem health., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

In this paper, we examine the intersections of parental support and family socioeconomic background within an undergraduate sample (N = 596) in a mid-sized Canadian Prairie city. Coresidence, financial support, and parental and professional financial advice are examined as types of 'family capital' that may be distributed unequally across socioeconomic groups. In keeping with previous literature, findings showed that students whose parents had university education and higher incomes received more robust coverage of their housing and school expenses. Students whose parents were university-educated were also more likely to be living with a parent, though no relationship was found between parental income and coresidence. Contrasting with previous literature, few relationships were found between socioeconomic background and receipt or influence of financial advice. These results contribute to the literature by generalising claims about family capital to a Canadian student sample, where relatively few studies have empirically examined intergenerational transfers as mechanisms for transmitting privilege during the transition to adulthood. With increasing demands for higher education and simultaneous declines in government subsidisation of its costs, disparate access to family capital is likely to intensify the reproduction of social inequality across generations., (© 2023 Canadian Sociological Association/La Société canadienne de sociologie.)

The vision of Chandler (Chan) S. Robbins for a continental-scale omnibus survey of breeding birds led to the development of the North American Breeding Bird Survey (BBS). Chan was uniquely suited to develop the BBS. His position as a government scientist had given him experience with designing and Implementing continental-scale surveys, his research background made him an effective advocate of the need for a survey to monitor pesticide effects on birds, and his prominence In the birding community gave him connections to Infrastructure--a network of qualified volunteer birders who could conduct roadside surveys with standardized point counts. Having started In the eastern United States and the Atlantic provinces of Canada In 1966, the BBS now provides population change Information for ~546 species In the continental United States and Canada, and recently Initiated routes In Mexico promise to greatly expand the areas and species covered by the survey. Although survey protocols have remained unchanged for 50 years, the BBS remains relevant In a changing world. Several papers that follow In this Special Section of The Condor: Ornithological Advances review how the BBS has been applied to conservation assessments, especially In combination with other large-scale survey data. A critical feature of the BBS program Is an active research program Into field and analytical methods to enhance the quality of the count data and to control for factors that Influence detectability. Papers In the Special Section also present advances In BBS analyses that Improve the utility of this expanding and sometimes controversial survey. In this Perspective, we Introduce the Special Section by reviewing the history of the BBS, describing current analyses, and providing summary trend results for all species, highlighting 3 groups of conservation concern: grassland-breeding birds, arldland-breedlng birds, and aerial Insectivorous birds. [ABSTRACT FROM AUTHOR]

Fumagilin-B is used to treat nosema infection in honey bee colonies; however, it is unclear whether treatment consistently reduces Vairimorpha ceranae (Fries et al.) abundance and improves colony strength and survival in the Canadian Prairies. This study assessed spring and fall fumagillin treatments on nosema abundance, colony strength, and mortality in 2 different beekeeping regions within Alberta, using both indoor and outdoor wintering management at each site. We compared 4 fumagillin treatments: Spring-only, Fall-only, Spring-and-Fall, and Control (no treatment). The spring treatment dose was ~68 mg/colony, whereas the fall treatment dose was 120 or 48 mg/colony, depending on the year. We found that the colonies were infected predominately with V. ceranae, with V. apis (Zander) present only in mixed infections in a subset of colonies. Although treatment in either the spring or fall did reduce nosema abundance in the short term, it did not eliminate the infection, making continued monitoring necessary. Colony strength was improved by spring treatment in some locations but not consistently, possibly due to the treatment timing or low dose. The combined spring and fall treatment increased colony survival over winter in one of 2 yr. Wintering method did not interact with treatment to affect nosema abundance in the spring. There does not appear to be a significant residual benefit of fall treatment as it did not reduce spring nosema abundance or increase colony population. Therefore, spring treatment should be applied to reduce spring V. ceranae abundance rather than relying on residual efficacy from previous fall treatments., (© The Author(s) 2023. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Mosquito seasonal activity is largely driven by weather conditions, most notably temperature, precipitation, and relative humidity. The extent by which these weather variables influence activity is intertwined with the animal's biology and may differ by species. For mosquito vectors, changes in weather can also alter host-pathogen interactions thereby increasing or decreasing the burden of disease., Methods: In this study, we performed weekly mosquito surveillance throughout the active season over a 2-year period in Manitoba, Canada. We then used Generalized Linear Mixed Models (GLMMs) to explore the relationships between weather variables over the preceding 2 weeks and mosquito trap counts for four of the most prevalent vector species in this region: Oc. dorsalis, Ae. vexans, Cx. tarsalis, and Cq. perturbans., Results: More than 265,000 mosquitoes were collected from 17 sampling sites throughout Manitoba in 2020 and 2021, with Ae. vexans the most commonly collected species followed by Cx. tarsalis. Aedes vexans favored high humidity, intermediate degree days, and low precipitation. Coquillettidia perturbans and Oc. dorsalis activity increased with high humidity and high rainfall, respectively. Culex tarsalis favored high degree days, with the relationship between number of mosquitoes captured and precipitation showing contrasting patterns between years. Minimum trapping temperature only impacted Ae. vexans and Cq. perturbans trap counts., Conclusions: The activity of all four mosquito vectors was affected by weather conditions recorded in the 2 weeks prior to trapping, with each species favoring different conditions. Although some research has been done to explore the relationships between temperature/precipitation and Cx. tarsalis in the Canadian Prairies, to our knowledge this is the first study to investigate other commonly found vector species in this region. Overall, this study highlights how varying weather conditions can impact mosquito activity and in turn species-specific vector potential., (© 2023. The Author(s).)

Edge effects resulting from adjacent land uses are poorly understood in agroecosystems yet understanding above and belowground edge effects is crucial for maintaining ecosystem function. The aim of our study was to examine impacts of land management on aboveground and belowground edge effects, measured by changes in plant community, soil properties, and soil microbial communities across agroecosystem edges. We measured plant composition and biomass, soil properties (total carbon, total nitrogen, pH, nitrate, and ammonium), and soil fungal and bacterial community composition across perennial grassland-annual cropland edges. Edge effects due to land management were detected both aboveground and belowground. The plant community at the edge was distinct from the adjacent land uses, where annual, non-native, plant species were abundant. Soil total nitrogen and carbon significantly decreased across the edge (P < 0.001), with the highest values in the perennial grasslands. Both bacterial and fungal communities were different across the edge with clear changes in fungal communities driven directly and indirectly by land management. A higher abundance of pathogens in the more heavily managed land uses (i.e. crop and edge) was detected. Changes in plant community composition, along with soil carbon and nitrogen also influenced the soil fungal community across these agroecosystems edges. Characterizing edge effects in agroecosystem, especially those associated with soil microbial communities, is an important first step in ensuring soil health and resilience in these managed landscapes., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Aguiar et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

TheGlenlea long-term study in Manitoba, Canada compares annual grain and forage-grain rotations under organic and conventional management. Organic systems are split into compost manure amended and no compost treatments. The objective of this study was to evaluate selected soil biological parameters over one entire growing season (2011). Microbial biomass carbon (MBC), microbial metabolic quotient (qCO 2 ), and microbial biomass phosphorus (MBP) were measured five times in spring wheat ( Triticum aestivum L.) and compared with a restored prairie grassland system. Significant interactions between management system and sample occasion were attributed to stronger recovery for MBC and MBP after soil rewetting in the organic vs the conventional system. The qCO 2 was lowest (0.37 mg C g MBC h −1 ) under dry mid-summer conditions and highest in late spring and after soil rewetting in fall (1.19 mg C g MBC h −1 ). When qCO 2 levels increased, the increase was greater in the forage-grain than the annual grain rotation. Organic management increased MBC compared with conventional management in the forage-grain rotation (1718 vs 1476 μg g −1 ) but decreased MBC in the annual grain rotation (1080 vs 1115 μg g −1 ). Among the six arable treatments, only the organic treatments in the forage-grain rotation behaved similarly (P > 0.05) to the grassland in terms of MBC, soil respiration and qCO 2 . N 2 O emissions per unit of MBC were 60–80% lower in organic compared with conventional systems. In conclusion, seasonal changes in soil biological C and P parameters were observed. Under conditions conducive to increased soil biological activity, organic systems outperformed conventional systems, especially in the forage-based rotation. [ABSTRACT FROM AUTHOR]

Lakes are sentinels of environmental changes within their watersheds including those induced by a changing climate and anthropogenic activities. In particular, contamination originating from point or non-point sources (NPS) within watersheds might be reflected in changes in the bacterial composition of lake water. We assessed the abundance of potentially pathogenic bacteria (PPB) sampled in 413 lakes within 8 southern Canadian ecozones that represent a wide diversity of lakes and watershed land use. The study objectives were (1) to explore the diversity of PPB; (2) to build a fecal multi-indicator from a cluster of co-occurring PPB; and (3) to predict the fecal multi-indicator over thousands of lakes. We identified bacterial taxa based on 16S rRNA amplicon sequencing and clustered 33 PPB matching taxa in the Canadian ePATHogen database using a Sørensen dissimilarity index on binary data across the sampled lakes. One cluster contained Erysipelothrix, Desulfovibrio, Bacteroides, Vibrio and Acholeplasma and was related to the NPS fraction of agriculture and pasture within the watershed as its main driver and thus it was determined as the fecal multi-indicator. We subsequently developed a fecal multi-indicator predictive model across 200 212 southern Canadian lakes which explained 55.1% of the deviance. Mapping the predictions showed higher fecal multi-indicator abundances in the Prairies and Boreal Plains compared to the other ecozones. These results represent the first attempt to map a potential fecal multi-indicator at the continental scale, which may be further improved in the future. Lastly, the study demonstrates the capacity of a multi-disciplinary approach leveraging both datasets derived from remote sensing and DNA sequencing to provide mapping information for public health governmental policies., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background: The long-lived terricolous larvae of click beetles, colloquially called wireworms, pose a significant threat to agriculture worldwide. Several economically important pest species have been documented in the Canadian Prairies, including Hypnoidus bicolor, Limonius californicus and Hypnoidus abbreviatus. However, most monitoring activities are performed in the early spring and there is evidence from other geographical regions of seasonal shifts in wireworm species composition and prevalence. Further, little is known about the overwintering physiology or behaviors of wireworms, which undoubtedly contribute to their population dynamics., Results: We surveyed wireworm populations from four Manitoban fields six times throughout the 2020 and 2021 growing seasons. Both Hypnoidus species were active throughout the spring and summer; however, L. californicus did not become active until later in the spring. Chill-coma recovery assays indicated Hypnoidus species recovered quicker than L. californicus from cold acclimation. Vertical migration assays simulating progressively lower ambient temperatures experienced by overwintering larvae identified H. bicolor throughout the soil profile, with L. californicus preferentially found at cooler, shallower depths. We speculate that these differences in species distribution within the soil column are due to the higher levels of putative cryoprotectants (for example, trehalose, sorbitol, glucose, glycerol) in L. californicus, as identified by targeted liquid chromatography tandem mass spectrometry., Conclusion: Our findings of a stark seasonal turnover in wireworm species prevalence and composition in the Canadian Prairies should be incorporated into future integrated pest management and surveillance activities. This study also advances our understanding of wireworm overwintering biology, which should be factored into current management approaches. © 2022 His Majesty the King in Right of Canada. Pest Management Science © 2022 Society of Chemical Industry. Reproduced with the permission of the Minister of Agriculture and Agri-Food Canada., (© 2022 His Majesty the King in Right of Canada. Pest Management Science © 2022 Society of Chemical Industry. Reproduced with the permission of the Minister of Agriculture and Agri-Food Canada.)

Abstract: Habitat fragmentation alters the edges of remnant habitat patches. We examined changes in the plant community and soil in relation to distance from edge and edge type for shrub-steppe and pine savannah grasslands in southern British Columbia, Canada. Community composition showed significant nonlinear relationships with distance-to-edge more frequently at paved roads and fruit crops than at dirt roads or control sites (i.e., in the interior of grassland patches), with changes typically extending 25–30m. More exotic species and fewer native species were found near edges, and edges showed decreased cryptogam cover and increased bare ground, especially near paved roads. The soil factors that best predicted compositional changes were soil pH and Cu/Mn at paved roads, soil pH and nitrogen at fruit crops, and soil resistance at dirt roads. Variation partitioning suggested that both direct (e.g., propagule pressure) and indirect (environmental change) factors mediated edge-related community changes, and provided evidence that nonlinear responses at developed edges were not due to natural gradients. Given the range of grassland patch sizes in this region (many patches 1–100ha), the edge effects we observed represent a considerable loss of “core” habitat, which must be accounted for in conservation planning and site restoration. [Copyright &y& Elsevier]

Wireworms are significant pests of a variety of economically important crops grown in the Canadian Prairies. These soil-dwelling larvae of click beetles feed on and burrow into the accessible underground plant tissues, which can result in cosmetic injury, stunting, wilting, and plant death. Successful management of wireworms relies on accurate estimations of their abundance and activity in infested fields. Bait trapping is the most commonly used method for sampling wireworms and standardized approaches have been developed; however, little work has been done to optimize trapping efficacy in different geographical regions. In this study, we evaluated the effect of bait trapping duration, seed formulation, and the causal relationship with CO2 production and soil temperature on the wireworm catch in three fields located in Manitoba, Canada. As expected, wireworm catch increased with trapping duration and placing traps in ground for 8 d is adequate in most cases. Both barley and wheat were more effective baits than soybean; however, barley released more CO2 (i.e., an attractant for wireworms) and performed better at elevated soil temperatures. Overall, the results of this study will serve as valuable guidelines to improve current wireworm sampling methods, and can be integrated into strategies aimed at managing these important pests to crop production., (© The Author(s) 2022. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Studies of intimate partner sexual assault (IPSA) and its effects on mental health are limited. This secondary data analysis examines IPSA, a history of child sexual abuse, depression, trauma, mental distress and quality of life in 665 Canadian women, 41% of whom had been sexually assaulted by intimate partners; 53% were sexually abused as children. Women who had experienced any IPSA had significantly higher scores on all Composite Abuse subscales (IPV), mental distress (SCL-10), and depression (CES-D-10). PTSD (PCL) was higher for women with both IPSA and CSA histories. Implications for advocates, clinicians, and researchers are presented.

Fusarium head blight (FHB) and Fusarium crown and root rot (FCRR) are major wheat diseases. Populations of FHB and FCRR pathogens are highly dynamic, and shifts in these populations in different regions is reported. Analyzing fungal populations associated with wheat node and grain tissues collected from different regions can provide useful information and predict diseases that might affect subsequent crops and effective disease management practices. In this study, wheat node and grain samples were collected from four representative sites across the western Canadian prairies in the 2018 growing season to characterize the major Fusarium spp. and other mycobiota associated with wheat in these regions. In total, 994 fungal isolates were recovered, and based on culture and molecular diagnostic methods, three genera constituted over 90% of all fungal isolates, namely Alternaria (39.6%), Fusarium (27.8%), and Parastagonospora (23.9%). A quantitative PCR (qPCR) diagnostic toolkit was developed to quantify the most frequently isolated Fusarium spp. in infected wheat tissues: Fusarium avenaceum , F. culmorum , F. graminearum , and F. poae . This qPCR specificity was validated in silico, in vitro, and in planta and proved specific to the target species. The qPCR results showed that F. graminearum was not detected frequently from wheat node and grain samples collected from four locations in this study. F. poae was the most abundant Fusarium species in grain samples in all tested locations. However, in node samples, F. culmorum (Beaverlodge and Scott) and F. avenaceum (Lacombe and Lethbridge) were the most abundant species. Trichothecene genotyping showed that the 3ADON is the most dominant trichothecene genotype (68%), followed by type-A trichothecenes (29.5%), whereas the 15ADON trichothecene genotype was least dominant (2.5%) and the NIV genotype was not detected. Moreover, a total of 129 translation elongation factor 1-alpha ( TEF1α ) sequences from nine Fusarium spp. were compared at the haplotype level to evaluate genetic variability and distribution. F. avenaceum and F. poae exhibited higher diversity as reflected by higher number of haplotypes present in these two species compared with the rest.

Abstract: The characteristic feature of the Prairie Pothole Region is a complex assemblage of mineral soil wetlands embedded in the dominantly agricultural landscape. Soils in these wetlands are loci of high potential greenhouse gas (GHG) emissions, and our objective was to provide estimates of greenhouse gas emissions and the controls on these emissions for typical wetlands of this region. Three years (2004–06) of N2O and CH4 emissions were taken from a large semi-permanent pond and five ephemeral freshwater mineral soil wetlands at the St. Denis National Wildlife Area (SDNWA) near Saskatoon, Saskatchewan, Canada. Methane emissions from the semi-permanent pond were low (ranging from 0.04 to 3.33g CH4 m−2 yr-1) but emissions from landscape elements of the ephemeral ponds were substantially higher, with a maximum of 138.6g CH4 m−2 yr−1 (or approximately 110g CH4 m−2 yr−1 when corrected for mid-day sampling bias) from basin centers of these ponds in 2005. The average annual CH4 emissions averaged across the three elements of the ephemeral ponds at SDNWA were 54.8g CH4 m−2 yr−1 in 2005 and 32.4g CH4 m−2 yr−1 in 2006. Methane emissions were significantly inversely correlated to SO4 2 concentrations of the pond water, which are in turn related to the balance between surface runoff and groundwater inputs into the ponds. The semi-permanent pond consistently had low annual N2O emissions (<0.4kg N2O–N ha−1 yr−1). N2O emissions from landscape elements within the ephemeral ponds showed considerable inter-annual variation, ranging from 0.09 to 1.0kg N2O–N ha−1 yr−1 for riparian grass elements, 0.3 to 0.6kg N2O–N ha−1 yr−1 for riparian tree, and 1.0 to 2.1kg N2O–N ha−1 yr−1 for basin centers. Major N2O emission events in the wetland elements were associated with periods of rapid drainage (i.e., from greater than 80% to less than 60% water-filled pore space) in the upper 15cm of the soil. Within-year patterns of N2O and CH4 emissions from soils of the ephemeral ponds were closely related to a second hydrological control, the area and duration of inundation in the ponds but negligible differences were observed between riparian grass and tree elements. The strong interactions between hydrology, water chemistry, and emissions of N2O and CH4 demonstrate the need for a landscape-scale assessment of GHG processes in these landscapes. [Copyright &y& Elsevier]

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Abstract: Aerial expansion of woody species in grasslands is common in arid and semiarid areas. The ecological consequences of shrub expansion, including ecosystem function and carbon sequestration, are complex and dependent on local environmental conditions. This research was conducted in the Northern Mixed Prairie of Canada to determine the effects of western snowberry (Symphoricarpos occidentalis) expansion on phytomass production and ecosystem carbon storage in grass-dominated plant communities. Total aboveground phytomass in western snowberry communities was more than triple that of the ecotone and 6-times greater than that of the grassland. Similarly, the mass of large roots was greatest in the western snowberry community (1.2±0.19kgm−2, mean±SE), intermediate in the ecotone (0.5±0.08kgm−2), and least in the grassland (0.1±0.04kgm−2). Conversely, the mass of fine and medium roots was not different (P >0.05) among the three communities, averaging 0.7kgm−2 in all communities. Greater aboveground phytomass did not correspond with greater organic carbon in the soil (SOC) in the western snowberry community possibly due to the poor quality and slow decomposition rate of shrub litter. Soil organic carbon in the upper 50cm averaged 8.3±0.7, 7.9±1.0, and 7.9±0.7kgm−2 in western snowberry, ecotone, and grassland communities, respectively. The SOC in fine- and coarse-textured soils averaged 10.4±0.6 and 6.2±0.4kgm−2, respectively. Expansion of western snowberry into grass-dominated plant communities does not appear to conflict with goals related to maintenance of SOC in the Northern Mixed Prairie. Soil texture had a greater effect on SOC than that of western snowberry. Therefore, the management of western snowberry in the Northern Mixed Prairie should be site specific and focus on aspects other than SOC pools. [Copyright &y& Elsevier]

Identifying causes of declines and evaluating effects of management practices on persistence of local populations of burrowing owls (Athene cunicularia) requires accurate estimates of abundance and population trends. Moreover, regulatory agencies in the United States and Canada typically require surveys to detect nest burrows prior to approving developments or other activities in areas that are potentially suitable for nesting burrowing owls. In general, guidelines on timing of surveys have been lacking and surveys have been conducted at different times of day and in different stages of the nesting cycle. We used logistic regression to evaluate 7 factors that could potentially affect probability of a surveyor detecting a burrowing owl nest. We conducted 1,444 detection trials at 323 burrowing owl nests within 3 study areas in Washington and Wyoming, USA, between February and August 2000-2002. Detection probability was highest during the nestling period and increased with ambient temperature. The other 5 factors that we examined (i.e., study area, time of day, timing within the breeding season, wind speed, % cloud cover) interacted with another factor to influence detection probability. Use of call-broadcast surveys increased detection probability, even during daylight hours when we detected >95% of owls visually. Optimal timing of surveys will vary due to differences in breeding phenology and differences in nesting behavior across populations. Nevertheless, we recommend ≥3 surveys per year: one that coincides with the laying and incubation period, another that coincides with the early nesting period, and a third that coincides with the late nestling period. In northern latitudes, surveys can be conducted throughout the day. [ABSTRACT FROM AUTHOR]

Abstract: The development of carbon (C) and nitrogen (N) simulations is one of the ongoing efforts in the land surface schemes of climate models. The C- and N-coupled Canadian Land Surface Scheme (C-CLASS) was recently modified to better represent grassland ecosystems. Improvements include revised plant growth and senescence calculations that are driven by the plant C balance between fixation and respiration, and leaf-out and leaf-fall schemes that are regulated by the seasonal dynamics of C and N reserves. These revisions were developed to better simulate the stress-related senescence and regrowth of perennials. The model was tested with observations of surface carbon and energy fluxes, soil temperature and moisture, and plant growth during 3 years of declining precipitation at a northern semiarid grassland near Lethbridge, Alberta, Canada. The R2 and standard deviations between the simulated and observed half-hourly fluxes were 0.95 and 22.5Wm-2 for net radiation, 0.82 and 42.1Wm-2 for sensible heat, 0.66 and 29.2Wm-2 for latent heat, and 0.63 and 0.95μmolCm-2s-1 for net CO2 exchange. The model and observations both showed a strong impact of declining precipitation on annual carbon budgets in this semi-arid grassland. In a wet year (1998, precipitation = 482mm), the ecosystem acted as a strong C sink (92gCm-2 modelled and 109gCm-2 measured from June 20th to December 31st). In a near-normal year (1999, precipitation = 341mm), a smaller C sink was indicated (24gCm-2 modelled and 21gCm-2 measured). In a dry year (2000, precipitation = 276mm), the ecosystem acted as a small C source (-18gCm-2 modelled and -17gCm-2 measured). [Copyright &y& Elsevier]

The Intermediate Disturbance Hypothesis states that the greatest species diversity occurs at intermediate levels of disturbance because species coexistence is maintained at a nonequilibrium state and no strong competitor can dominate completely. On the other hand, diversity of exotic species is expected to increase with the disturbance magnitude. These patterns were tested for in this study. The cover of all vascular plants, mosses, and lichens in 1 × 1 m plots across a range of disturbance levels was sampled in 11 remnant grasslands within the Aspen Parkland Ecoregion of central Alberta, western Canada. The Intermediate Disturbance Hypothesis was supported for small-scale within-patch diversity for total species richness and Simpson's diversity index. Lower species diversity was found in undisturbed and lightly grazed as well as in highly disturbed plots. Intermediate levels of disturbance had reduced dominance of Festuca hallii (Vasey) Piper and increased abundance of most other species; this gave the highest species diversity. The species richness and diversity of exotic plant species showed a significant positive relationship with the magnitude of the disturbance. Understanding relationships between disturbance and plant species diversity, especially exotic plants, can influence management decisions on what disturbance regime is conducive to maintaining natural plant communities.Key words: Intermediate Disturbance Hypothesis, diversity, exotic species, grassland.L'hypothèse des perturbations intermédiaires énonce qu'une plus grande diversité en espèces survient à des degrés intermédiaires de perturbation, parce que la co-existence des espèces est maintenue dans un état de non-équilibre et qu'aucun puissant compétiteur peut complètement dominer. D'un autre côté, on s'attend à ce que la diversité des espèces exotiques augmente avec le degré de perturbation. Les auteurs vérifient ces patrons dans leur étude. Ils ont échantillonné la couverture de toutes les plantes vasculaires, mousses et lichens sur des parcelles de 1 m × 1 m, distribuées selon un ensemble de niveaux de perturbation variés, dans 11 prairies vestigiales de l'éco-région de Aspen Parkland située au centre de l'Alberta, dans l'ouest canadien. L'hypothèse de la perturbation intermédiaire se vérifie quant à la diversité à petite échelle, à l'intérieur des parcelles, pour la richesse en espèces et l'index de diversité de Simpson. On retrouve une diversité en espèces plus faible dans les parcelles non-perturbées et légèrement pâturées, ainsi que dans les parcelles fortement perturbées. Les niveaux intermédiaires de perturbation montrent une réduction de la dominance par le Festuca hallii (Vasey) Piper, et une augmentation de l'abondance de la plupart des autres espèces; ceci conduit à la plus grande diversité. La richesse en espèces et la diversité des plantes exotiques montre une relation significative avec l'ampleur de la perturbation. La compréhension des relations qui existent entre les perturbations et la diversité des espèces, surtout des plantes exotiques, peut influencer les décisions d'aménagement à savoir quel régime de perturbation permet le mieux de maintenir les communautés de plantes naturelles.Mots clés : hypothèse de perturbation intermédiaire, diversité, espèces exotiques, prairie. [ABSTRACT FROM AUTHOR]

It is generally accepted that land use and land management practices impact climate change through sequestration of carbon in soils, but modulation of surface energy budget can also be important. Using Landsat data to characterize cropland albedos in Canada's three prairie soil zones, this study estimates the atmospheric carbon equivalent drawdown of albedo radiative forcing for three management practices: 1) moving from conventional tillage to no-till, 2) eliminating summer fallow in crop rotations, and 3) growing crops with higher albedos. In a 50-year time horizon, conversion from conventional tillage to no-till results in a total equivalent atmospheric CO 2 (CO 2 -eq) drawdown of 1.0-1.5 kg m -2 , and conversion from summer fallow to crops results in CO 2 -eq drawdown of 1.1-2.4 kg m -2 . Conversion of summer fallow to crops results in different magnitudes of CO 2 -eq drawdown depending on specific crops. Lentils, peas, and canola have relatively higher albedo than that of spring wheat and flax; hence, a larger magnitude of CO 2 -eq drawdown results when they replace summer fallow in the rotation. For the management changes from 1990 to 2019 for the whole Canadian Prairies, albedo changes induced a CO 2 -eq drawdown of about 179.3 ± 20.9 Tg due to increased area of no-till, and 101.6 ± 9.5 Tg due to reduced area under fallow. The study shows that the magnitudes of CO 2 -eq drawdown due to albedo change are comparable to that due to soil carbon sequestration. Therefore, it is important to account for cropland albedo changes in assessing the potential of agricultural management practices to mitigate climate change., (Crown Copyright © 2021. Published by Elsevier Ltd. All rights reserved.)

The global crop sector is estimated to contribute about 10.4% of global GHGs annually. The Canadian crop sector is assessed as adding about 6.5% to total national emissions. These estimates over report the impact of farming as they ignore the complex interaction of cropping with the environment and the role land use, land use change and forestry (LULUCF) play in sequestering carbon. This study quantifies the contribution of land use to GHG emissions and removals in the Canadian Prairies crop sector between 1985 and 2016. The modeling effort explores how different farming practices (i.e., conventional tillage (CT), minimum tillage (MT), zero tillage (ZT), summerfallow, crop rotations, and residue retention) and input usage rates (i.e., fertilizer and fuel) affect GHG emissions in different soil climate zones and provinces in the Prairies region. The adoption of sustainable practices led to an 80% decline in GHG emissions in the crop sector between 1985 and 2016. Since 2005, the baseline for Canada's Paris commitment, sectoral emissions dropped 53%, more than is required to meet the 2030 target. Most promising, the crop sector was a net GHG sink between 2013 and 2016 in Alberta and between 2006 and 2016 in Saskatchewan. As positive as these developments have been, more can be done by directing research to identify options for reducing GHGs in Manitoba (which made only minimal improvements as farmers there faced conditions requiring continuous use of conventional tillage practices), to explore better nitrogen management (a major continuing source of GHG from cropping) and by searching for low carbon transport options., Competing Interests: The authors have declared that no competing interests exist.

Biobeds are agriculture-based bioremediation tools used to safely contain and microbially degrade on-farm pesticide waste and rinsate, thereby reducing the negative environmental impacts associated with pesticide use. While these engineered ecosystems demonstrate efficient pesticide removal, the microbiomes in these environments remain largely understudied both taxonomically and functionally. This study used metagenomic and metatranscriptomic techniques to characterize the microbial community in a two-cell Canadian biobed system before and after a field season of pesticide application. These culture-independent approaches identified an enrichment of xenobiotic-degrading bacteria, such as Afipia, Sphingopyxis and Pseudomonas, and enrichment and transcription of xenobiotic-degrading genes, such as peroxidases, oxygenases, and hydroxylases, among others; we were able to directly link the transcription of these genes to Pseudomonas, Oligotropha, Mesorhizobium, Rhodopseudomonas, and Stenotrophomonas taxa., (© 2021 Society for Applied Microbiology and John Wiley & Sons Ltd.)

Pollen extracts from five locally-common grassland species in eastern Ontario, Canada were tested for in vitro allelopathic effect on the pollen germination of 17 sympatric target species in 1987. The flowering phenologies of the test and target species were recorded to determine if any phenologically-divergent species showed evidence of in vitro pollen-allelopathic interactions. Phleum pratense L. demonstrated pollen-allelopathic effects on all targets except Linaria vulgaris Hill. P. pratense L. also exhibited significant phenological divergence with seven of the target species. Pollen extracts from Agrostis stolonifera L., Melilotus alba Desr., and Vicia cracca L. inhibited pollen germination in some of the target species, but the results suggest that these effects were pH-mediated. The pollen extract of Erigeron annuus (L.) Pers. did not cause inhibition of pollen germination in any of the target species. Further tests with pollen extract of P. pratense and another 23 sympatric target species were performed in 1988. Pollen germination was significantly inhibited in all but two of these species: A. stolonifera and P. pratense. Hence, the pollen of P. pratense was not auto-allelopathic. The breeding system, relatively tall growth habit and relatively large quantity of pollen produced all support the in vitro evidence of P. pratense as a Pollen-allelopathic species. [ABSTRACT FROM AUTHOR]