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Herbaceous perennial wetland monocots in Northern Ontario, Canada, show dichotomous root overwintering patterns, either with full senescence in autumn or survival over the winter, comparable to deciduous and evergreen leaf habits in trees. To test if these root strategies differ in their associations with growing season length, soil temperatures were recorded in autumn, winter and spring on 38 wetland sites with their dominant species being either of these two root overwintering strategies, altogether 19 monocot species. Traits associated with these strategies were assessed in garden experiments for a subset of these species. Sites with species with autumn-senescing roots were, on average, warmer than sites with species with overwintering roots. The 13 coldest sites were all sites of species with overwintering roots. Spring shoot growth in the field was delayed in species with autumn-senescing roots, despite their higher shoot relative growth rates in the garden, possibly due to the necessity to produce roots first. We conclude that species with autumn-senescing roots are more constrained by temperature than species with overwintering roots, limiting their occurrence in cool climates to locally warm soils and constraining their distribution towards the north. This is comparable to constraints on distribution of deciduous and evergreen trees., (© 2019 The Authors. New Phytologist © 2019 New Phytologist Trust.)

Existing estimates of methane fluxes from North American wetlands vary widely in both magnitude and distribution. In light of these disagreements, this study uses atmospheric methane observations from the US and Canada to analyze seven different bottom-up, wetland methane estimates reported in a recent model comparison project. We first use synthetic data to explore how well atmospheric observations can constrain wetland fluxes. We find that observation sites can identify an atmospheric pattern from Canadian wetlands but not reliably from US wetlands. The network can also identify the spatial distribution of fluxes in Canada at multi-province spatial scales. Based upon these results, we then use real data to evaluate the magnitude, temporal distribution, and spatial distribution of each model estimate. Most models overestimate the magnitude of fluxes across Canada. Most predict a seasonality that is too narrow, potentially indicating an over-sensitivity to air or soil temperatures. In addition, the LPJ-Bern model has a spatial distribution that is most consistent with atmospheric observations. Unlike most models, LPJ-Bern utilizes land cover maps, not just remote sensing inundation data, to estimate wetland coverage. A flux model with a constant spatial distribution outperforms most other existing flux estimates across Canada. [ABSTRACT FROM AUTHOR]

A large portion of Canada is covered by wetlands; mapping and monitoring them is of great importance for various applications. In this regard, Remote Sensing (RS) technology has been widely employed for wetland studies in Canada over the past 45 years. This study evaluates meta-data to investigate the status and trends of wetland studies in Canada using RS technology by reviewing the scientific papers published between 1976 and the end of 2020 (300 papers in total). Initially, a meta-analysis was conducted to analyze the status of RS-based wetland studies in terms of the wetland classification systems, methods, classes, RS data usage, publication details (e.g., authors, keywords, citations, and publications time), geographic information, and level of classification accuracies. The deep systematic review of 128 peer-reviewed articles illustrated the rising trend in using multi-source RS datasets along with advanced machine learning algorithms for wetland mapping in Canada. It was also observed that most of the studies were implemented over the province of Ontario. Pixel-based supervised classifiers were the most popular wetland classification algorithms. This review summarizes different RS systems and methodologies for wetland mapping in Canada to outline how RS has been utilized for the generation of wetland inventories. The results of this review paper provide the current state-of-the-art methods and datasets for wetland studies in Canada and will provide direction for future wetland mapping research. [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.)

Wetland buffer zones (WBZs) are riparian areas that form a transition between terrestrial and aquatic environments and are well-known to remove agricultural water pollutants such as nitrogen (N) and phosphorus (P). This review attempts to merge and compare data on the nutrient load, nutrient loss and nutrient removal and/or retention from multiple studies of various WBZs termed as riparian mineral soil wetlands, groundwater-charged peatlands (i.e. fens) and floodplains. Two different soil types ('organic' and 'mineral'), four different main water sources ('groundwater', 'precipitation', 'surface runoff/drain discharge', and 'river inundation') and three different vegetation classes ('arboraceous', 'herbaceous' and 'aerenchymous') were considered separately for data analysis. The studied WBZs are situated within the temperate and continental climatic regions that are commonly found in northern-central Europe, northern USA and Canada. Surprisingly, only weak differences for the nutrient removal/retention capability were found if the three WBZ types were directly compared. The results of our study reveal that for example the nitrate retention efficiency of organic soils (53 ± 28%; mean ± sd) is only slightly higher than that of mineral soils (50 ± 32%). Variance in load had a stronger influence than soil type on the N retention in WBZs. However, organic soils in fens tend to be sources of dissolved organic N and soluble reactive P, particularly when the fens have become degraded due to drainage and past agricultural usage. The detailed consideration of water sources indicated that average nitrate removal efficiencies were highest for ground water (76 ± 25%) and lowest for river water (35 ± 24%). No significant pattern for P retention emerged; however, the highest absolute removal appeared if the P source was river water. The harvesting of vegetation will minimise potential P loss from rewetted WBZs and plant biomass yield may promote circular economy value chains and provide compensation to land owners for restored land now unsuitable for conventional farming., 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 © 2020 Elsevier B.V. All rights reserved.)

Copyright of Canadian Journal of Remote Sensing 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.)

Great Lakes coastal wetlands have critically important ecological values and functions. However, coordinated monitoring of coastal wetland quantity and quality is lacking. The Great Lakes Coastal Wetlands Consortium was formed in 2000 to address this critical need for North American Great Lakes. This paper presents the background, framework, objectives, and current and future work of the Consortium. The Consortium consists of wetlands researchers and managers from the United States and Canada. Several Consortium members present papers on specific topics in this journal issue. The Consortium's goal is to design a plan for implementing a long-term monitoring program focused on a concise set of environmental indicators. A year of development work and a year of field work have been completed to date. The Consortium is currently working toward final development and implementation of the monitoring program. [ABSTRACT FROM AUTHOR]

Freely-available satellite data streams and the ability to process these data on cloud-computing platforms such as Google Earth Engine have made frequent, large-scale landcover mapping at high resolution a real possibility. In this paper we apply these technologies, along with machine learning, to the mapping of peatlands–a landcover class that is critical for preserving biodiversity, helping to address climate change impacts, and providing ecosystem services, e.g., carbon storage–in the Boreal Forest Natural Region of Alberta, Canada. We outline a data-driven, scientific framework that: compiles large amounts of Earth observation data sets (radar, optical, and LiDAR); examines the extracted variables for suitability in peatland modelling; optimizes model parameterization; and finally, predicts peatland occurrence across a large boreal area (397, 958 km2) of Alberta at 10 m spatial resolution (equalling 3.9 billion pixels across Alberta). The resulting peatland occurrence model shows an accuracy of 87% and a kappa statistic of 0.57 when compared to our validation data set. Differentiating peatlands from mineral wetlands achieved an accuracy of 69% and kappa statistic of 0.37. This data-driven approach is applicable at large geopolitical scales (e.g., provincial, national) for wetland and landcover inventories that support long-term, responsible resource management. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Reviews 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.)

Snow is a vital component of the earth system, yet no snow-focused satellite remote sensing platform currently exists. In this study, we investigate how synthetic observations of snow water equivalent (SWE) representative of a synthetic aperture radar remote sensing platform could improve spatiotemporal estimates of snowpack. We use a fraternal twin observing system simulation experiment, specifically investigating how much snow simulated using widely used models and forcing data could be improved by assimilating synthetic observations of SWE. We focus this study across a 24∘×37∘ domain in the western USA and Canada, simulating snow at 250 m resolution and hourly time steps in water year 2019. We perform two data assimilation experiments, including (1) a simulation excluding synthetic observations in forests where canopies obstruct remote sensing retrievals and (2) a simulation inferring snow distribution in forested grid cells using synthetic observations from nearby canopy-free grid cells. Results found that, relative to a nature run, or assumed true simulation of snow evolution, assimilating synthetic SWE observations improved average SWE biases at maximum snowpack timing in shrub, grass, crop, bare-ground, and wetland land cover types from 14 %, to within 1 %. However, forested grid cells contained a disproportionate amount of SWE volume. In forests, SWE mean absolute errors at the time of maximum snow volume were 111 mm and average SWE biases were on the order of 150 %. Here the data assimilation approach that estimated forest SWE using observations from the nearest canopy-free grid cells substantially improved these SWE biases (18 %) and the SWE mean absolute error (27 mm). Simulations employing data assimilation also improved estimates of the temporal evolution of both SWE and runoff, even in spring snowmelt periods when melting snow and high snow liquid water content prevented synthetic SWE retrievals. In fact, in the Upper Colorado River region, melt-season SWE biases were improved from 63 % to within 1 %, and the Nash–Sutcliffe efficiency of runoff improved from -2.59 to 0.22. These results demonstrate the value of data assimilation and a snow-focused globally relevant remote sensing platform for improving the characterization of SWE and associated water availability. [ABSTRACT FROM AUTHOR]

Polarimetric Synthetic Aperture Radar (PolSAR) imagery is a complex multi-dimensional dataset, which is an important source of information for various natural resources and environmental classification and monitoring applications. PolSAR imagery produces valuable information by observing scattering mechanisms from different natural and man-made objects. Land cover mapping using PolSAR data classification is one of the most important applications of SAR remote sensing earth observations, which have gained increasing attention in the recent years. However, one of the most challenging aspects of classification is selecting features with maximum discrimination capability. To address this challenge, a statistical approach based on the Fisher Linear Discriminant Analysis (FLDA) and the incorporation of physical interpretation of PolSAR data into classification is proposed in this paper. After pre-processing of PolSAR data, including the speckle reduction, the H/α classification is used in order to classify the basic scattering mechanisms. Then, a new method for feature weighting, based on the fusion of FLDA and physical interpretation, is implemented. This method proves to increase the classification accuracy as well as increasing between-class discrimination in the final Wishart classification. The proposed method was applied to a full polarimetric C-band RADARSAT-2 data set from Avalon area, Newfoundland and Labrador, Canada. This imagery has been acquired in June 2015, and covers various types of wetlands including bogs, fens, marshes and shallow water. The results were compared with the standard Wishart classification, and an improvement of about 20% was achieved in the overall accuracy. This method provides an opportunity for operational wetland classification in northern latitude with high accuracy using only SAR polarimetric data. [ABSTRACT FROM AUTHOR]

This paper presents and demonstrates a spatial framework for the application of strategic environmental assessment (SEA) in the context of change analysis for urban wetland environments. The proposed framework is focused on two key stages of the SEA process: scoping and environmental baseline assessment. These stages are arguably the most information-intense phases of SEA and have a significant effect on the quality of the SEA results. The study aims to meet the needs for proactive frameworks to assess and protect wetland habitat and services more efficiently, toward the goal of advancing more intelligent urban planning and development design. The proposed framework, adopting geographic information system and remote sensing tools and applications, supports the temporal evaluation of wetland change and sustainability assessment based on landscape indicator analysis. The framework was applied to a rapidly developing urban environment in the City of Saskatoon, Saskatchewan, Canada, analyzing wetland change and land-use pressures from 1985 to 2011. The SEA spatial scale was rescaled from administrative urban planning units to an ecologically meaningful area. Landscape change assessed was based on a suite of indicators that were subsequently rolled up into a single, multi-dimensional, and easy to understand and communicate index to examine the implications of land-use change for wetland sustainability. The results show that despite the recent extremely wet period in the Canadian prairie region, land-use change contributed to increasing threats to wetland sustainability. [ABSTRACT FROM AUTHOR]

Industrial development within Canada's boreal zone has increased in recent decades. Forest management activities, pulp and paper operations, electric power generation, mining, conventional oil and gas extraction, nonconventional oil sand development, and peat mining occur throughout the boreal zone with varying impacts on water resources. We review impacts of these industries on surface water, groundwater, and wetlands recognizing that heterogeneity in the dominance of different hydrologic processes (i.e., precipitation, evapotranspiration, groundwater recharge, and runoff generation) across the boreal zone influences the degree of impacts on water resources. Through the application of best management practices, forest certification programs, and science-based guidelines, timber, pulp and paper, and peat industries have reduced their impacts on water resources, although uncertainties remain about long-term recovery following disturbance. Hydroelectric power developments have moved toward reducing reservoir size and creating more natural flow regimes, although impacts of aging infrastructure and dam decommissioning is largely unknown. Mineral and metal mining industries have improved regulation and practices, but the legacy of abandoned mines across the boreal zone still presents an ongoing risk to water resources. Oil and gas industries, including non-conventional resources such as oil sands, is one of the largest industrial users of water and, while significant progress has been made in reducing water use, more work is needed to ensure the protection of water resources. All industries contribute to atmospheric deposition of pollutants that may eventually be released to downstream waters. Although most industrial sectors strive to improve their environmental performance with regards to water resources, disruptions to natural flow regimes and risks of degraded water quality exist at local to regional scales in the boreal zone. Addressing the emerging challenge of managing the expanding, intensifying, and cumulative effects of industries in conjunction with other stressors, such as climate change and atmospheric pollution, across the landscape will aid in preserving Canada's rich endowment of water resources. [ABSTRACT FROM AUTHOR]

Flows from river basins in northwestern Canada have been rising in the last two decades as a result of climate warming. In the wetland-dominated basins that characterise the southern margin of permafrost, permafrost thaw and disappearance, and resulting land-cover change, is occurring at an unprecedented rate. The impact of this thaw on runoff generation in headwater basins is poorly understood. Permafrost thaw has the potential to fundamentally alter the cycling and storage of moisture inputs in this region by altering the type and relative proportions of the major land-cover types, such as peat plateaus, channel fens and flat bogs. This paper examines streamflow changes in the four Water Survey of Canada gauged river basins (152-2050 km2) in the lower Liard River valley, Northwest Territories, Canada, a region where permafrost thaw has produced widespread loss of forest and concomitant expansion of permafrost-free wetlands. Annual runoff in the lower Liard Valley increased by between 112 and 160 mm over the period of 1996-2012. The Mann-Kendall non-parametric statistical test and the Kendall-Theil robust line were used to ascertain changes in streamflow. Historical aerial photographs from 1977 and high-resolution satellite imagery (WorldView 2) from 2010 were used to measure the rate and pattern of permafrost thaw in a representative 6 km2 area of Scotty Creek. Permafrost thaw-induced land-cover change is both increasing the adjacency between runoff producing and transmitting land cover types and transforming certain land covers that store water into ones that produce runoff. This land-cover change was found to be the single most important factor (37-61 mm) contributing to the observed increase in river discharge. Other contributing factors include increases in plateau runoff contributing areas (20-32 mm), increases in annual effective precipitation depth (18-30 mm), contribution of water from the melt of ice within permafrost (9 mm) and increases in baseflow (0.9-6.8 mm). Although runoff has significantly ( p < 0.05) increased in all four basins, the largest increases are in basins with a relatively high cover of flat bogs. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Sulfonylurea herbicides are widely used in crop production on the Canadian prairies and a portion of these herbicides applied to cropland are inevitably lost to surrounding aquatic ecosystems. Little is known regarding the presence of sulfonylurea herbicides in wetlands located amongst cropland. This paper describes a new analytical method for the extraction and the determination of seven sulfonylurea herbicides (thifensulfuron-methyl, tribenuron-methyl, ethametsulfuron-methyl, metsulfuron-methyl, rimsulfuron, nicosulfuron and sulfosulfuron) in wetland sediment. The method provided > 85% analyte recovery from fortified sediment for six of the seven sulfonylurea herbicides with a limit of quantification (LOQ) of 1.0 μ g kg- 1. Tribenuron-methyl had significantly lower recovery compared to the other six sulfonylurea herbicides (LOQ = 2 μ g kg- 1). Mean recovery standard deviations were < 10%. This methodology was used to quantify sulfonylurea herbicide residues in sediment samples collected from prairie wetlands situated within the agricultural landscape of Saskatchewan and Manitoba, Canada. This is the first-known detection of sulfonylurea herbicide residues in prairie wetland sediments. Ethametsulfuron-methyl, sulfosulfuron and metsulfuron-methyl, the three most environmentally persistent of the seven sulfonylurea herbicides monitored in the surveillance component of this study, were most frequently detected in wetland sediment with mean concentrations ranging from 1.2 to 10 μ g kg- 1. [ABSTRACT FROM AUTHOR]

Lake St. Pierre (LSP), constituted of a 120 km2 stretching of the St. Lawrence River (Southern Québec), hosts the largest freshwater fishery industry in Canada. The lake drains, through its main tributaries, an important area of agrarian land and was subjected to intense industrial activities in the past century. In this paper, we present (1) an estimation of the seasonal aquatic mercury (Hg) inputs to LSP from the St-Lawrence River and two major tributaries; (2) a reconstruction, by the analysis of sediment cores, of the historic inputs of Hg into LSP and in a large riparian wetland, Bay St. François. Our results indicate that the aquatic Hg inputs to LSP (290 kg Hg between April 2003 and April 2004) are moderately elevated with most of the inputs occurring from the St. Lawrence River, either in spring or early winter, during high flow episodes. The sediment profiles suggest a recent decrease in Hg inputs, likely attributable to improvements of industrial practices. The observed perturbation of the surface sediments give evidence of an active hydrodynamic regime, suggesting that LSP could only act as a transitory system for suspended sediment and Hg, with seasonal accumulation and recurrent re-suspension resulting from changes in the hydrodynamic regime. Finally, we observed positive MeHg fluxes from the sediment to the water at different seasons in Bay St. François. However, Hg levels in fish like walleyes of LSP are reported to be low, which could be explained by faster fish growth rates following in part intense fishing pressure in LSP. [ABSTRACT FROM AUTHOR]

This paper discusses results of a nested basin study investigating run-off responses along the watercourse in a 137 km² subarctic Canadian Shield watershed. Catchment areas contributing surface run-off to the basin outlet shrink after a maximum during spring snowmelt because of storage demands in headwater wetlands and lakes. This decrease is significant as summer contributing areas to the basin outlet are only 4% the size of spring melt contributing areas. This reduction in contributing area and decrease in antecedent lake levels lead to a two order of magnitude decrease in run-off ratios from spring snowmelt to midsummer. Furthermore, the attenuating influence of lakes on the run-off hydrograph increases the opportunity for evaporative losses, which prevents small run-off events from maintaining a measurable flood wave through the basin. The location at which a run-off event is interrupted in the watercourse is a function of lake size relative to upstream run-off inputs. Run-off is more susceptible to evaporative losses in large receiving lakes where inflow per unit area is less. These processes cause intermittent streamflow through the basin. These results have repercussions for coupled atmospheric/hydrological models whose resolution is approaching the basin scale. The incorporation of lateral transfer schemes that encompass these processes and physiographic influences on streamflow response is encouraged. [ABSTRACT FROM AUTHOR]

The Peace-Athabasca Delta (PAD) is one of the world’s largest freshwater deltas. Many of its shallow (<1.5 m) lakes and wetlands are perched above surrounding waterways. The delta has experienced a number of wetting and drying intervals. The latest drying trend ended in 1996 when high waters, generated under ice-jam and open-water conditions, recharged a number of the perched basins. The objective of this study was to determine the relative importance of hydroclimatic components on the persistence of water. A water-balance model was developed to simulate water-level responses following a flood event. Basin response was tested against a range of historical hydroclimatic conditions that have occurred in the delta during the 20th century. Ponded water duration in a 0.8 m deep perched basin was 5 years for the cool-dry period of the 1920s, slightly longer for the post-1974 flood era, and up to 9 years for the wet conditions of the 1940s and 1950s. Water drawdown occurred in almost every year and was almost exclusively due to evaporation exceeding precipitation. Net groundwater flux was minimal. Given the overlying importance of the floodwater component in the water balance of perched basins, the next step is to investigate the causes, spatial sources and frequency of flooding. This water balance model presented in this paper offers a useful tool for the management of the duration of water in perched wetlands of the PAD, which can help preserve essential habitat for wildlife. [ABSTRACT FROM AUTHOR]

Up-to-date information on the distribution and changes associated with wetlands is essential for their effective conservation and management. Satellite remote sensing is arguably the only practical way for mapping and monitoring wetlands in a timely manner over a large area, and therefore has been chosen by the Canadian Wetland Inventory (CWI) initiative to map Canada's wetlands and by the Environment and Sustainable Development Indicators (ESDI) initiative to monitor the extent of wetlands indicators. As a contribution to these initiatives, this paper presents a rule-based wetland mapping method using Landsat-7/ETM+, two-season Radarsat-1/SAR images and DEM data. Three study sites in eastern Canada were selected to test this new method. The test results indicate that the classification accuracy of the new method ranges from 71% to 92%, for open bog, open fen, treed bog, marsh and swamp at the three sites. In comparison, two traditional methods based on Landsat-7/ETM+ alone or both Landsat-7/ETM+ and Radarsat-1/SAR have accuracies of 24-89% and 78-85% respectively. [ABSTRACT FROM AUTHOR]

Seasonal forest pools (SFPs) are geographically- and hydrologically-isolated ponded wetlands, in that they are topographically isolated from other surface waters. SFPs occur commonly throughout the temperate forests of the eastern United States and adjacent Canada. SFPs are ephemeral in occurrence, typically drying annually. The regular drying of SFPs excludes fish from these habitats, and as a result, they are the preferred breeding habitat of some amphibians, notably ambystomid (‘mole’) salamanders and wood frogs ( Rana sylvatica Le Conte). The pools also support a rich and diverse invertebrate fauna. The duration of the wet phase, or hydroperiod of SFPs, has been repeatedly shown to be the dominant influence on the composition and fitness of the faunal community of the pools. Despite the importance of SFP hydrology, it is a poorly studied subject. This paper reviews the limited state-of-knowledge of seasonal forest pool hydrology and associated basin morphology. The review discusses findings from studies of other isolated ponded wetlands that could be applicable to our understanding of the hydrology of SFPs. [ABSTRACT FROM AUTHOR]

We examined soil properties and accumulation rates over the last ca. 100 years in four swamps and four marshes in southern Canada where these wetlands are common but under increasing anthropogenic pressure. One 50‐cm long core was collected from each wetland and analyzed to determine bulk density (BD) and organic matter (OM). Lead‐210 and cesium‐137 dating were used to estimate sediment accumulation rates. In the datable portion of each core, we determined the organic carbon (Corg), nitrogen (N), Corg/OM, Corg/N, Corg density, Corg stocks, and Corg accumulation rates. All parameters but one—Corg accumulation rates—were significantly different in swamps compared to marshes and between seasonally wet soils and those regularly flooded. Since 1950, Corg stocks varied from 6 to 13.6 kg m−2 with ≈23% more Corg in swamps than in marshes. When hydrology and deeper soils where considered, Corg stocks in regularly flooded wetlands were 60% higher than those of seasonally wet systems, emphasizing the role of hydrology in building up C stocks long‐term. Our measurements are within the wide range reported for similar systems in North America. The average rate of Corg accumulation in the studied wetlands (112 ± 87 g m−2 yr−1) is ≈50% higher than that of oligotrophic/ombrotrophic peatlands, but ≈47% lower than in tidal marshes from eastern Canada. Our study lends support to the case for wetland restoration through re‐wetting as an important nature‐based climate solution for mitigation of GHG emissions in areas where they were drained for agriculture and other purposes. Plain Language Summary: Wetlands are important ecosystems because they have an enhanced capacity to extract carbon dioxide—a greenhouse gas—from the atmosphere and store it in the ground as partly decomposed plant carbon. This ground storage is vital because it keeps carbon dioxide from increasing in the atmosphere where it causes global warming. Among the Earth's wetlands, freshwater marshes and swamps from temperate climates are among the least understood. To address this limitation, we conducted a study in southern Canada, where these wetlands are common but under increasing pressure from farming and urban development. Our results indicate that while marshes (dominated by grasses and sedges) form mostly mineral soils with less carbon stocks than swamps (vegetated with shrubs and trees), which form organic soils, the rate at which they accumulate carbon in their soil is similar. We also show that the wetlands we studied are 50% more effective in storing carbon than the cold climate bogs (vegetated by mosses), but they are less effective than salt marshes which form along the shores of temperate seas. We suggest that if freshwater marshes and swamps are protected, they can be important natural solutions in the mitigation of carbon dioxide emitted by human activity. Key Points: Carbon stocks in eight nutrient‐rich freshwater wetlands ranged 18–40 kg m−2, with organic soils averaging ≈60% more than mineral soilsMean carbon accumulation rate over the last 100 years was 112 g m−2 yr1, with no significant differences between swamps and marshesCarbon accumulation rates were higher than in oligotrophic/ombrotrophic wetlands (bogs) but lower than in tidal salt marshes [ABSTRACT FROM AUTHOR]

This study examines the response of a cold-regions deltaic wetland ecosystem in northwestern Canada to two separate and differing seasonal wetting cycles. The goal of this paper was to examine the nature of reflected electromagnetic energy measured by earth observation (EO) satellites, and to assess whether seasonal wetland hydroperiod and episodic flooding events impact the information retrieved by the Sentinel-2 sensors. The year 2018 represents a year characterized by a large spring freshet and ice-jam flooding, while 2019 represents a year characterized more by summer open-water flooding. We applied the Modified Normalized Difference Wetness Index (MNDWI) to address the effects of the wetting cycles. The response of the vegetative cover was tracked using the fraction of the absorbed photosynthetically active radiation (fAPAR) and the Leaf Area Index (LAI). All three indices were viewed through the lens of cover classes as derived through a previously published study by the authors. The study provides a framework for designing longer-term studies where multiple intra- and inter-annual hydrological cycles can be accessed via EO data. Future studies will enable the examination of lag times inherent in the response to the various water sources applied to spectral response and incorporate this EO approach into a monitoring framework. [ABSTRACT FROM AUTHOR]

Wetlands are important ecosystems that are linked to climate change mitigation. As 25% of global wetlands are located in Canada, accurate and up-to-date wetland classification is of high importance, nationally and internationally. The advent of deep learning techniques has revolutionized the current use of machine learning algorithms to classify complex environments, specifically in remote sensing. In this paper, we explore the potential and possible limitations to be overcome regarding the use of ensemble deep learning techniques for complex wetland classification and discusses the potential and limitation of various solo convolutional neural networks (CNNs), including DenseNet, GoogLeNet, ShuffleNet, MobileNet, Xception, Inception-ResNet, ResNet18, and ResNet101 in three different study areas located in Newfoundland and Labrador, Canada (i.e., Avalon, Gros Morne, and Grand Falls). Moreover, to improve the classification accuracies of wetland classes of bog, fen, marsh, swamp, and shallow water, the results of the three best CNNs in each study area is fused using three supervised classifiers of random forest (RF), bagged tree (BTree), Bayesian optimized tree (BOT), and one unsupervised majority voting classifier. The results suggest that the ensemble models, in particular BTree, have a valuable role to play in the classification of wetland classes of bog, fen, marsh, swamp, and shallow water. The ensemble CNNs show an improvement of 9.63–19.04% in terms of mean producer's accuracy compared to the solo CNNs, to recognize wetland classes in three different study areas. This research indicates a promising potential for integrating ensemble-based learning and deep learning for operational large area land cover, particularly complex wetland type classification. [ABSTRACT FROM AUTHOR]

This paper applies a social return on investment (SROI) analysis to the issue of flood control and wetland conservation in the Smith Creek basin of southeastern Saskatchewan, Canada. Basin hydrological modeling applied to wetland loss and restoration scenarios in the study area provides local estimates of the ecosystem service (ES) provision related to flood control and nutrient removal. Locally appropriate monetary values are applied to these services to gauge the cost effectiveness of wetland conservation funding at two levels: flood control capacity alone and then incorporating a suite of ES. SROI ratios for flood control alone provide ratios between 3.17 (retention) and 0.80 (full restoration) over 30 years; when other ES are included, the ratios increase, ranging from 7.70 (retention) to 2.98 (full restoration) over 30 years. Retention of existing wetlands provides the highest SROI and therefore we argue that government policy should focus on preventing further loss of wetlands as a strategic investment opportunity. Overall, these results indicate that wetland retention is an economically viable solution to limit the financial, social and environmental damages of flooding in Saskatchewan specifically and the Prairie Pothole Region (PPR) generally. [ABSTRACT FROM AUTHOR]

Wetlands are one of the most productive environments in the world. Despite their importance for water and carbon cycle regulation, wildlife survival and economic value, human activities along with severe climate changes have led to critical loss and degradation of these ecosystems. In Canada, where these lands still occupy a notable percentage of the territory (~ 14%), efficient strategies and public awareness measures to protect them are required. The Open Government program fosters accessibility to a large amount of data for developing approaches and applications that contribute to this purpose. Web cartographic implementations represent a potential tool for integration and diffusion of diversified information that can support the protection of natural habitats. In this paper, we present an open-source geo-platform that supports multi-scale management of wetlands and biodiversity in Quebec. This friendly and dynamic prototype allows integration of multisource data, providing, as well, the possibility of geovisualization and correlation analysis of possible stressors impacting these ecosystems. This system proposes useful and easy-to-use functionalities that can facilitate identification of possible habitats in danger. The prototype proposed is flexible and can be adapted to assist other biodiversity studies as well as the practical needs of responsible groups such as planners, conservationists and landscape managers. [ABSTRACT FROM AUTHOR]

The article presents an overview of factors affecting the evolution of coastal wetlands of the Laurentian Great Lakes. Coastal wetlands have important ecological, economic and social roles in the Great Lakes ecosystem. The land and open waters of the Great Lakes provides coastal protection, water purification and habitat for many species of fauna and flora. To conserve and better protect the Great Lakes coastal wetlands, cooperation between all levels of government and the public is essential to avert the mistakes of the past and prevent any further degradation and loss of Great Lakes wetlands. This is best accomplished when public consultations that include residents, private organizations, industry and governments are part of the decision making process.

Wetland drainage has been pervasive in the North American Prairie Pothole Region. There is strong evidence that this drainage increases the hydrological connectivity of previously isolated wetlands and, in turn, runoff response to snowmelt and rainfall. It can be hard to disentangle the role of climate from the influence of wetland drainage in observed records. In this study, a basin-classification-based virtual modelling approach is described that can isolate these effects on runoff regimes. The basin class which was examined, entitled Pothole Till, extends throughout much of Canada's portion of the Prairie Pothole Region. Three knowledge gaps were addressed. First, it was determined that the spatial pattern in which wetlands are drained has little influence on how much the runoff regime was altered. Second, no threshold could be identified below which wetland drainage has no effect on the runoff regime, with drainage thresholds as low as 10 % in the area being evaluated. Third, wetter regions were less sensitive to drainage as they tend to be better hydrologically connected, even in the absence of drainage. Low flows were the least affected by drainage. Conversely, during extremely wet years, runoff depths could double as the result of complete wetland removal. Simulated median annual runoff depths were the most responsive, potentially tripling under typical conditions with high degrees of wetland drainage. As storage capacity is removed from the landscape through wetland drainage, the size of the storage deficit of median years begins to decrease and to converge on those of the extreme wet years. Model simulations of flood frequency suggest that, because of these changes in antecedent conditions, precipitation that once could generate a median event with wetland drainage can generate what would have been a maximum event without wetland drainage. The advantage of the basin-classification-based virtual modelling approach employed here is that it simulated a long period that included a wide variety of precipitation and antecedent storage conditions across a diversity of wetland complexes. This has allowed seemingly disparate results of past research to be put into context and finds that conflicting results are often only because of differences in spatial scale and temporal scope of investigation. A conceptual framework is provided that shows, in general, how annual runoff in different climatic and drainage situations will likely respond to wetland drainage in the Prairie Pothole Region. [ABSTRACT FROM AUTHOR]

The water content of wetlands represents a key driver of their hydrological services and it is highly dependent on short- and long-term weather conditions, which will change, to some extent, under evolving climate conditions. The impact on stream flows of this critical dynamic component of wetlands remains poorly studied. While hydrodynamic modelling provide a framework to describe the functioning of individual wetland, hydrological modelling offers the opportunity to assess their services at the watershed scale with respect to their type ( i.e. , isolated or riparian). This study uses a novel approach combining hydrological modelling and limited field monitoring, to explore the effectiveness of wetlands under changing climate conditions. To achieve this, two isolated wetlands and two riparian wetlands, located in the Becancour River watershed within the St Lawrence Lowlands (Quebec, Canada), were monitored using piezometers and stable water isotopes (δD – δ18O) between October 2013 and October 2014. For the watershed hydrology component of this study, reference (1986–2015) and future meteorological data (2041–2070) were used as inputs to the PHYSITEL/HYDROTEL modelling platform. Results obtained from in-situ data illustrate singular hydrological dynamics for each typology of wetlands ( i.e., isolated and riparian) and support the hydrological modelling approach used in this study. Meanwhile, simulation results indicate that climate change could affect differently the hydrological dynamics of wetlands and associated services ( e.g., storage and slow release of water), including their seasonal contribution ( i.e., flood mitigation and low flow support) according to each wetland typology. The methodological framework proposed in this paper meets the requirements of a functional tool capable of anticipating hydrological changes in wetlands at both the land management scale and the watershed management scale. Accordingly, this framework represents a starting point towards the design of effective wetland conservation and/or restoration programs. [ABSTRACT FROM AUTHOR]

Wetland habitat continues to be lost to cumulative effects of development on the landscape. Part of the problem is that there currently exists only limited guidance as to how to use the existing scientific tools, conceptual frameworks and guidance documents to advance cumulative effects assessment (CEA) from the project scale to the broader regional scale at which land-use planning occurs. To strengthen CEA science for wetlands there are three minimum requirements: (1) understand the baseline science of wetland functions; (2) delineate the primary drivers (anthropogenic and natural) of disturbance; and (3) develop the science to link drivers to changes in wetland function in an interactive, synergistic and cumulative way. The paper concludes by identifying ways in which the state of CEA science and management of wetlands could be improved. [ABSTRACT FROM PUBLISHER]

Abstract: Notwithstanding various environmental assessment legislations and policies for wetland conservation in Canada, wetland habitat continues to be lost to the cumulative effects of development on the landscape. Ensuring no net loss of wetlands requires consideration of the direct, indirect, and potentially induced effects of development; however, many projects that affect wetlands are often deemed insignificant and do not trigger any formal environmental assessment process. When such small scale or routine projects are assessed, indirect and induced effects, and in particular effects to small or seasonal wetlands, are often not included in impact assessment and subsequent wetland mitigation. As a result, mitigation of the total or cumulative effects to wetlands is often insufficient or completely lacking in development planning and impact assessment. Part of the problem is that there currently exists only limited guidance as to how to identify effects to wetlands in project planning and environmental assessment for relatively routine, small-scale projects. In response, this paper presents a methodological framework for the integration of effects to wetlands in project planning and environmental assessment application. Focused on effects to wetlands from linear developments, in particular transportation corridors, a four-phase, nine-step assessment framework is developed to provide guidance to effects assessment for wetlands during the early stages of project planning. The framework will aid practitioners and regulators in identifying the potential effects of a project to wetlands, and in determining the acceptability of impact management practices. Although situated in the Canadian context, the framework and principles are broadly applicable in other jurisdictions. [ABSTRACT FROM AUTHOR]

Two wetland plant species (Mimulus ringens L. [monkey-flower] and Bidens cernua L. [bur-marigold]), two terrestrial species (Sinapis arvensis L. [wild mustard] and Phaseolus vulgaris L. [beans-variety, Kentucky blue]), and one species found in both wet and dry habitats (Echinochloa crusgalli [L.] Beauv. [bamyardgrass]) were exposed to 1% (0.045 g a.i./ha) and 10% (0.45 g a.i./ha) of recommended label rate of metsulfuron methyl, a sulfonylurea herbicide used in western Canada. The objective of the study was to investigate the effect of metsulfuron methyl on these plant species and to determine the most sensitive phenological stage. Chemical analyses of herbicide residues showed that there was good correspondence between the quantity measured in the tank mix compared with that detected on glass fiber papers, the latter representing the dose reaching the test plants during the spray event. All species exhibited marked effects on the vegetative growth andreproductive performance when sprayed at 10% label rate. Less pronounced but significant effects were shown at 1 % label rate. Seed weight was reduced for B. cernua and S. arvensis. The seedling stage was the most sensitive period for all species tested, although surviving plants sprayed at later stages showed considerable effects on the reproductive parts. All species tested would be at risk from small doses of metsulfuron methyl drifting away from the sprayed areas. This study highlights the shortcomings of the current testing schemes requiredprior to pesticide registration. [ABSTRACT FROM AUTHOR]

Constructed wetlands have gained acceptance as a means of treating stormwater runoff from urban developments. Much of the available data regarding the performance of these facilities is based upon monitoring conducted over the course of less than two years, and as such inherently assumes that the period of analysis represents the "typical" or "design" conditions under which these facilities are intended to operate. While this information has provided guidance regarding the mechanisms by which wetlands provide quality treatment of urban runoff, it does not fully reflect the variability of conditions under which the facilities operate over the fullness of time, which is of particular concern to designers and operators. The construction of the Dartnall Road Interchange, as part of Hamilton's Lincoln Alexander Parkway, required a monitoring program—which included five years of water quality sampling—as a condition of approval by the Department of Fisheries and Oceans. This paper reports on the quantitative and qualitative wetland water quality monitoring data (sediment, nutrients, metals) obtained over the course of a total seven-year program, and provides information regarding the operating conditions and estimates on contaminant removal efficiencies from the facilities. [ABSTRACT FROM AUTHOR]

Biological treatment of wastewater has been employed successfully for many types of industries. Aerobic processes have been used extensively. Production of large amounts of sludge is the main problem and methods such as biofilters and membrane bioreactors are being developed to combat this phenomenon. Anaerobic waste treatment has undergone significant developments and is now reliable with low retention times. The UASB, the original high rate anaerobic reactor, is now becoming less popular than the EGSB reactor. New developments such as the Annamox process are highly promising for nitrogen removal. For metal removal, processes such as biosorption and biosurfactants combined with ultrafiltration membranes are under development. Biosurfactants have also shown promise as dispersing agents for oil spills. If space is available, wetlands can be used to reduce biological oxygen demand (BOD), total suspended solids (TSS), nutrients and heavy metals. These innovative processes are described in this paper in terms of applications, the stage of development, and future research needs particular to Canada. [ABSTRACT FROM AUTHOR]

All of the pollutants found in stormwater runoff at airports, including surface and aircraft de-icing/anti-icing glycols, can be treated and removed to low levels in well-designed sub-surface flow (SSF) constructed wetland systems. There are two common forms of constructed wetlands used for pollution control: those where water flows over the surface among wetland plants (free water surface or marsh type wetlands); and SSF types where the wastewater flows below the normally dry surface of a gravel substrate in which the wetland plants grow. SSF wetlands have no open water to attract waterfowl and are particularly suitable for use at airports. Of the glycol used at Edmonton International Airport (EIA), 80 to 90% eventually entered surface runoff. Edmonton International Airport's operator, the Edmonton Regional Airports Authority (Edmonton Airports) evaluated a number of glycol management options, including constructed wetlands. As a result, a very large SSF wetland system was installed to handle glycol-contaminated stormwater. This paper reviews results of a feasibility study carried out to define design parameters and scale up kinetics for this wetland system, the detailed design that resulted, the SSF wetland's construction, and the start-up of the Edmonton facilities in August of 2000. It also compares the Edmonton wetland system with a similar facility at Heathrow Airport in the United Kingdom. [ABSTRACT FROM AUTHOR]

The Peace-Athabasca Delta, Canada, is a 3900 km[sup2] freshwater wetland complex, characterized by numerous river channels, lakes and wetland basins. Periodic flooding of the wetland basins is necessary to maintain the productivity in the delta. The delta experienced a 22 year drying trend between 1974 and 1996, resulting in considerable changes in water boundaries. Availability of water is the dominant mechanism driving the ecosystem response. As such, accurate and frequently updated maps of floodwater extent and vegetation types are necessary for proper wetland management. Owing to the large size, remoteness, and dynamic nature of the delta, flood mapping is only feasible using remote sensing. This paper evaluates the use of radar and visible/infrared satellite imagery for mapping the extent of flooded wetland areas. The extent of standing water in the delta during May 1996 and May 1998 was mapped using RADARSAT and SPOT imagery. The RADARSAT scenes, the SPOT scenes, and a combination of the two were, for each year, classified into open water, flooded vegetation, and non-flooded land using a Mahalanobis distance classifier. When the 1996 RADARSAT scene and the 1996 SPOT scene were classified separately, they resulted in Kappa coefficients of 70% and 66% respectively. The accuracy increased to 92% when the RADARSAT and the SPOT scenes were combined and classified together. Classification of the 1998 RADARSAT scene and the 1998 SPOT scene resulted in accuracies of 76% and 80% respectively, whereas a combination of the two scenes resulted in an accuracy of 92%. The results from this study indicate that the information from radar and visible/infrared satellite imagery is complementary and that flood mapping in wetland areas can be achieved with higher accuracy if the two image types are used in combination. [ABSTRACT FROM AUTHOR]

Some wetlands in the northern Great Plains support hundreds to thousands of late-stage tadpoles providing important sources of recruitment to the Wood Frog (Lithobates sylvaticus) population while many other wetlands produce none. Relationships between water quality and late-stage tadpole abundance were determined to identify the water quality parameters associated with tadpole abundance. Water samples were collected, and late-stage tadpole abundances were assessed once each year in late June for 12 years in 26 wetlands. Catch or abundance was the number of tadpoles captured in 30 min with a dip-net. The catch of tadpoles was variable both among wetlands and over the long-term for individual wetlands, and ranged from 0 to several hundred individuals. Wood Frog tadpoles were especially sensitive to sodium and chloride concentrations. At Cl concentrations less than 5 mg/L, occupancy for late-stage tadpoles was 84%, and declined by about 8% for each 5 mg/L increase in Cl to 40.1 mg/L Cl, the maximum concentration associated with the detection of tadpoles. Optimal water quality for late-stage Wood Frog tadpoles included low concentrations of Na (x ¯ = 8.1 mg/L), and Cl (x ¯ = 4.2 mg/L) relative to total dissolved solids and other ions, and high concentrations of phosphorus. In a landscape where ion concentrations in wetlands can range over 3 orders of magnitude, water quality analyses suggest that abundant Wood Frog tadpole populations occur in wetlands dominated by snow-melt runoff with its characteristic low ion concentrations. The present study highlights the importance to amphibian conservation of the water quality environment of tadpole habitat. [ABSTRACT FROM AUTHOR]

In the discontinuous permafrost zone of the Northwest Territories (NWT), Canada, snow covers the ground surface for half the year. Snowmelt constitutes a primary source of moisture supply for the short growing season and strongly influences stream hydrographs. Permafrost thaw has changed the landscape by increasing the proportional coverage of permafrost‐free wetlands at the expense of permafrost‐cored peat plateau forests. The biophysical characteristics of each feature affect snow water equivalent (SWE) accumulation and melt rates. In headwater streams in the southern Dehcho region of the NWT, snowmelt runoff has significantly increased over the past 50 years, despite no significant change in annual SWE. At the Fort Simpson A climate station, we found that SWE measurements made by Environment and Climate Change Canada using a Nipher precipitation gauge were more accurate than the Adjusted and Homogenized Canadian Climate Dataset which was derived from snow depth measurements. Here, we: (a) provide 13 years of snow survey data to demonstrate differences in end‐of‐season SWE between wetlands and plateau forests; (b) provide ablation stake and radiation measurements to document differences in snow melt patterns among wetlands, plateau forests, and upland forests; and (c) evaluate the potential impact of permafrost‐thaw induced wetland expansion on SWE accumulation, melt, and runoff. We found that plateaus retain significantly (p < 0.01) more SWE than wetlands. However, the differences are too small (123 mm and 111 mm, respectively) to cause any substantial change in basin SWE. During the snowmelt period in 2015, wetlands were the first feature to become snow‐free in mid‐April, followed by plateau forests (7 days after wetlands) and upland forests (18 days after wetlands). A transition to a higher percentage cover of wetlands may lead to more rapid snowmelt and provide a more hydrologically‐connected landscape, a plausible mechanism driving the observed increase in spring freshet runoff. [ABSTRACT FROM AUTHOR]

Background: The functioning of ecosystems is highly variable through space and time. Climatic and edaphic factors are forcing ecological communities to converge, whereas the diversity of plant assemblages dampens these effects by allowing communities' dynamics to diverge. This study evaluated whether the growing season phenology of wetland plant communities within landscapes is determined by the climatic/edaphic factors of contrasted regions, by the species richness of plant communities, or by the diversity of plant assemblages. From 2013 to 2016, we monitored the phenology and floristic composition of 118 wetland plant communities across five landscapes distributed along a gradient of edaphic and climatic conditions in the Province of Québec, Canada. Results: The growing season phenology of wetlands was driven by differences among plant assemblage within landscapes, and not by the species richness of each individual community (< 1% of the explained variation). Variation in the growing season length of wetlands reflected the destabilizing effect of climatic and edaphic factors on greenup dates, which is opposed to the dampening effect of plant assemblage diversity on green-down dates. Conclusions: The latter dampening effect may be particularly important in the context of increasing anthropogenic activities, which are predicted to impair the ability of wetlands to adapt to fluctuating environmental conditions. Our findings suggest that stakeholders should not necessarily consider local species-poor plant communities of lower conservation value to the global functioning of wetland ecosystems. [ABSTRACT FROM AUTHOR]

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River temperature exerts a critical control on habitat for aquatic biota. As the climate warms in eastern Canada, threats to habitats of cold‐water species will increase, underpinning the necessity to develop an understanding of landscape‐scale, thermal regimes of flowing waters. We assessed the performance of spatial statistical network (SSN) models of river temperature using high‐resolution thermal infrared imagery (0.6 m) and LiDAR (1 m) compared to NASA's Shuttle Radar Topography Mission (SRTM—30 m) topographic data and interrogate LiDAR derived fine‐scale models (3 ha) to describe groundwater connectivity to surface waters in catchments with shallow overburden and varied bedrock geology. LiDAR improved model performance in a catchment underlain by a homogeneous, high hydraulic conductance bedrock (Cains River) but did not improve model performance in a catchment with heterogeneous bedrock and variable hydraulic conductance (North Pole Stream). We hypothesize that differences in bedrock conductance modified topographic controls on subsurface flows and discharge patterns to the rivers and thus produced the mixed performance of the SSN models. At finer scales, river reaches in steep valleys incising high conductance bedrock produced groundwater discharge, which was absent in incised valleys with low conductance bedrock. These findings indicate that while topography exerts an important control on landscape‐scale hydrological processes, geologic setting is a similarly important influence on hydrological processes. We suggest the inclusion of a third dimension of spatial autocorrelation, representative of the vertical plane that captures the geologic setting, would broaden the geographic applicability of spatial statistical models for river temperature studies. Key Points: Spatial statistical river network models had mixed success in predicting river temperature in differing geologic and topographic settingsValley incision in shallow, high hydraulic conductance bedrock facilitated groundwater discharge associated with cool river temperaturesValley incision in shallow, low hydraulic conductance bedrock limited groundwater discharge and was associated with warm river temperatures [ABSTRACT FROM AUTHOR]

Wetland decline under post-European settlement and land use change across western Canada has led to mitigation strategies, including wetland creation. Created wetlands can trigger environmental change, including woody species encroachment, in turn altering vegetation and soil. We quantify changes in shrub abundance from prior to wetland creation (1949) until 60 years later (2012) within a Mixedgrass ecosystem of the Verger watershed in Alberta, Canada. In addition, we compare remaining grassland with areas colonized by shrubland on similar ecosites for differences in (1) plant composition, including native and introduced flora, (2) herbage yield and forage accessibility for livestock, and (3) soil properties (surface organic depth, bulk density, mineral nitrogen (N), and carbon (C) concentration). Repeat photos show Shepherdia argentea shrublands increased from 0 to 88 ha (to 1.15% of study area) following wetland creation, with the greatest increase in the last 20 years. Relative to grasslands, shrublands had lower total plant diversity but greater presence of introduced plant species. Shrub patches were 94% lower in herbaceous production, with 77% of shrublands non-utilized by cattle, collectively leading to reduced grazing capacity. Relative to grasslands, shrublands had a thicker soil surface mulch layer, and where cattle were present, had increased mineral soil N and C. Overall, shrub encroachment following wetland creation has markedly altered vegetation and soils in this once grassland landscape, with negative impacts on native plant diversity, herbage production and forage accessibility, and has implications for the management of shrub encroachment. [ABSTRACT FROM AUTHOR]

Prior meta-regression models (MRMs) of wetland values pool value estimates associated with diverse commodity types—for example recreation, flood control, nutrient cycling, habitat provision, nonuse value, and carbon sequestration. Neither theory nor economic intuition justify the inclusion of such dissimilar commodities within a single meta-analytic value function, leading to validity concerns. This article seeks to advance methods for commodity and welfare consistent MRMs, applied to a particular category of wetland values. We develop a wetland value MRM restricted to a specific wetland type (coastal marshes), general location (US and Canada), commodity type (habitat provision and services), and valuation approach (stated preference methods). Results indicate that willingness to pay per household for marsh habitat changes is responsive to scope, spatial scale, market extent, the type of habitat change, household characteristics, and other factors suggested by theory and intuition. Results supersede those of prior wetland value MRMs in terms of statistical performance, estimation of anticipated value surface patterns, and capacity to support conceptually valid benefit transfers. Comparison with an otherwise identical but less commodity consistent MRM demonstrates that commodity consistency leads to improved statistical and benefit transfer performance. [ABSTRACT FROM AUTHOR]

The global offtake of wild animals is valued at US$400 billion annually and supports the livelihoods of 15% of the global population. Wetlands are amongst the most important ecosystems globally, but offtake may represent a substantial pressure. This study assessed the availability of information and evaluated the offtake of wild animals from wetlands by focussing on fish and waterbirds. A literature search identified 2726 studies on wetland offtake. Scoping of these resulted in 82 studies that contained quantitative information on fish or waterbird offtake. Fishing offtake statistics for inland waters are collated nationally by some governments, but other sources of information are few. Reporting of fish offtake for species or across scales was constrained by insufficient detail, even in relatively well-documented countries such as Bangladesh. Although government hunting statistics from Europe and North America were available, there was little waterbird data from less economically developed countries. The case of Canada indicated that the species richness and composition of waterbirds taken varied between indigenous subsistence and recreational hunting communities. Hidden (unquantified) offtake, of both fish and waterbirds, hinders obtaining precise data for offtake, which may threaten the conservation of species and the sustainability of wetland ecosystems. [ABSTRACT FROM AUTHOR]

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Classification and clustering approaches provide a means to group watersheds according to similar attributes, functions, or behaviours, and can aid in managing natural resources. Although they are widely used, approaches based on hydrological response parameters restrict analyses to regions where well-developed hydrological records exist, and overlook factors contributing to other management concerns, including biogeochemistry and ecology. In the Canadian Prairie, hydrometric gauging is sparse and often seasonal. Moreover, large areas are endorheic and the landscape is highly modified by human activity, complicating classification based solely on hydrological parameters. We compiled climate, geological, topographical, and land-cover data from the Prairie and conducted a classification of watersheds using a hierarchical clustering of principal components. Seven classes were identified based on the clustering of watersheds, including those distinguishing southern Manitoba, the pothole region, river valleys, and grasslands. Important defining variables were climate, elevation, surficial geology, wetland distribution, and land cover. In particular, three classes occur almost exclusively within regions that tend not to contribute to major river systems, and collectively encompass the majority of the study area. The gross difference in key characteristics across the classes suggests that future water management and climate change may carry with them heterogeneous sets of implications for water security across the Prairie. This emphasizes the importance of developing management strategies that target sub-regions expected to behave coherently as current human-induced changes to the landscape will affect how watersheds react to change. The study provides the first classification of watersheds within the Prairie based on climatic and biophysical attributes, with the framework used being applicable to other regions where hydrometric data are sparse. Our findings provide a foundation for addressing questions related to hydrological, biogeochemical, and ecological behaviours at a regional level, enhancing the capacity to address issues of water security. [ABSTRACT FROM AUTHOR]

Peatland development and carbon accumulation on the Pacific coast of Canada have received little attention in paleoecological studies, despite wetlands being common landscape features. Here, we present a multi–proxy paleoenvironmental study of an ombrotrophic bog in coastal British Columbia. Following decreases in relative sea level, the wetland was isolated from marine waters by 13,300 cal yr BP. Peat composition, non-pollen palynomorph, and C and N analyses demonstrate terrestrialization from an oligotrophic lake to a marsh by 11,600 cal yr BP, followed by development of a poor fen, and then a drier ombrotrophic bog by 8700 cal yr BP. Maximum carbon accumulation occurred during the early Holocene fen stage, when seasonal differences in insolation were amplified. This highlights the importance of seasonality in constraining peatland carbon sequestration by enhancing productivity during summer and reducing decomposition during winter. Pollen analysis shows that Pinus contorta dominated regional forests by 14,000 cal yr BP. Warm and relatively dry summers in the early Holocene allowed Pseudotsuga menziesii to dominate lowland forests 11,200–7000 cal yr BP. Tsuga heterophylla and P. menziesii formed coniferous forest in the mid- and late Holocene. Tephra matching the mid-Holocene Glacier Peak–Dusty Creek assemblage provides evidence of its most northwesterly occurrence to date. [ABSTRACT FROM AUTHOR]

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Saline wetlands represent potential natural analogs for reclaimed wetlands in the Athabasca Oil Sands Region (AOSR). Thus, an understanding of the drivers of salinity changes in natural wetlands can provide insight into how reconstructed peatlands in the AOSR may evolve given that they are constructed with saline oil sands reclamation materials. Here, we investigate the nature of salinity changes from the analysis of sediment cores at three ponds situated within a saline peat-forming wetland near Fort McMurray (Alberta). Past changes in salinity were reconstructed using weighted-averaging transfer functions based on diatoms and an environmental dataset from 32 saline boreal ponds. Results reveal complex 'precipitation-surface water-groundwater' interactions associated with differences in the hydrologic functioning of the studied ponds, and their connectivity with shallow groundwater aquifers and adjacent wetlands. Relationships between cumulative departure from mean precipitation and DI-salinity suggest that precipitation may control salinity both directly and indirectly. In ponds recharged predominantly by meteoric water, precipitation may govern salinity directly by dilution of salt content in water, so that rises in precipitation result in a salinity decline. In ponds situated within a saline groundwater discharge zone, salinity may be influenced by precipitation indirectly through recharge of the saline aquifer, so increases in precipitation lead to rises in salinity. Our study suggests that complex salinity response to precipitation change, coupled with notable range of salinity fluctuation within natural saline fens should be considered while designing saline constructed wetlands and predicting their potential resilience under climate change. [ABSTRACT FROM AUTHOR]

Copyright of Condor: Ornithological Applications is the property of Oxford University Press / USA 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.)