A5089127079- Soil and Water Nutrient Dynamics
- Hydrology and Watershed Management Studies
- Peatlands and Wetlands Ecology
- Aquatic Ecosystems and Phytoplankton Dynamics
- Groundwater and Isotope Geochemistry
- Fish Ecology and Management Studies
- Mine drainage and remediation techniques
- Cryospheric studies and observations
- Marine and coastal ecosystems
- Aquatic Invertebrate Ecology and Behavior
- Soil erosion and sediment transport
- Urban Stormwater Management Solutions
- Water Quality and Pollution Assessment
- Freshwater macroinvertebrate diversity and ecology
- Heavy metals in environment
- Forest ecology and management
- Hydrology and Sediment Transport Processes
- Integrated Water Resources Management
- Water Quality and Resources Studies
- Soil Carbon and Nitrogen Dynamics
- Fire effects on ecosystems
- Environmental Toxicology and Ecotoxicology
- Smart Materials for Construction
- Soil and Unsaturated Flow
- Seedling growth and survival studies
Trent University
2014-2024
Ministry of the Environment, Conservation and Parks
2005-2009
Ministry of Environment
2009
University of Waterloo
2003-2004
Swedish University of Agricultural Sciences
2004
Winter is an understudied but key period for the socioecological systems of northeastern North American forests. A growing awareness importance winter season to forest ecosystems and surrounding communities has inspired several decades research, both across northern at other mid- high-latitude around globe. Despite these efforts, we lack a synthetic understanding how climate change may impact hydrological biogeochemical processes social economic activities they support. Here, take advantage...
Dissolved organic carbon (DOC) fluxes at eight headwater basins in south-central Ontario were strongly related to seasonal streamflow, and extreme events contributed both interannual intercatchment variability. Six catchments with high stream DOC greater peatland coverage exhibited a different pattern of concentration compared two low less wetland influence. In wetland-dominated catchments, concentrations decreased during fall wet-up spring melt, because the dominance melt period annual...
Total phosphorus (TP) levels in many Canadian Shield lakes central Ontario have declined over recent decades, despite increases human activity most watersheds. To investigate the contribution of changes catchment export to long-term declines lake TP, we examined temporal and spatial patterns TP concentrations (1980–1981 2001–2002) across 11 subcatchments that drain into three which average ice-free by approximately 35%. Annual stream decreased significantly 30%–89% eight subcatchments,...
Abstract “Weather whiplash” is a colloquial phrase for describing an extreme event that includes shifts between two opposing weather conditions. Prior media coverage and research on these types of extremes have largely ignored winter events. However, rapid swings in can result crossing from frozen to unfrozen conditions, or vice versa; thus, the potential impact events coupled human natural systems may be large. Given rapidly changing conditions seasonally snow‐covered regions, there...
In response to large reductions in sulphur (S) emissions over the past 30 years, sulphate (SO42−) concentrations precipitation at Plastic Lake south-central Ontario, Canada, have declined by more than 70%. More recent decreases NOx similarly led a reduction nitrate deposition (NO3−) and consequently pH of bulk has increased approximately 0.8 units since 1980. Despite decrease acidic deposition, chemical recovery streams, as measured an increase aluminum (Al), been much less expected,...
Increased nitrate (NO3) concentrations in streamwaters draining forested catchments are reportedly an early indicator of nitrogen (N) saturation. Nitrate streams 16 south central Ontario were monitored over a 16-year period, during which time N bulk deposition was relatively constant (∼9 kg ha-1 yr-1). Mean annual NO3 both highly variable among and years, although patterns concentration similar many catchments. Coherence analysis identified two stream groupings. Shallow soils, moderate...
Abstract Rising dissolved organic carbon (DOC) concentrations observed at a number of sites in the northern hemisphere over recent decades are subject much debate, and reports suggest link between DOC patterns surface waters changes sulphate (SO 4 ) related to droughts or deposition. In order investigate potential influence SO concentration on south‐central Ontario, we used long‐term (1980–2001) stream monitoring data from wetland‐dominated catchment (Plastic Lake‐1 subcatchment, PC1) that...
Abstract Stream chemistry is often used to infer catchment‐scale biogeochemical processes. However, cycling in the near‐stream zone or hydrologically connected areas may exert a stronger influence on stream compared with processes occurring more distal parts of catchment, particularly dry seasons and years. In this study, we tested hypotheses that wetland proportion better predictor seasonal (winter, spring, summer, fall) whole‐catchment averages these relationships are dryer periods lower...
In this study we have analyzed the hydrochemical effect of drought conditions during 311 hydrological episodes in nine headwater streams central Ontario over past 20 years. Acid Neutralization Capacity (ANC) was logarithmically correlated (p<0.05) to antecedent discharge eight streams, with largest decline ANC occurring after low flow. SO4(2-) most important driving mechanism decline, but dilution as well organic acidity several streams. No decrease driven observed year period despite a...
Abstract Sulphate concentrations in two headwater lakes and their major inflows were evaluated over an 18 year period (1980–81 to 1997–98) during which time sulphate bulk deposition declined by approximately 40%. The lake catchments represent either end of the spectrum acid sensitivity Muskoka–Haliburton region Ontario. Between 1980 1998, Harp Plastic Lakes decreased, but decrease was much less than expected (28% 21% respectively) given magnitude change deposition. export streams draining...
Abstract Winter climatic conditions can influence the timing and magnitude of water nitrate (NO 3 –N) export from seasonally snow‐covered catchments. Specifically, mid‐winter rain‐on‐snow (ROS) events are a major source NO –N to forested streams, but impact these on other nutrients is not known. Climate projections for Ontario suggest that climate warming will be most pronounced during winter months, which could result in more rain consequent changes nutrient delivery streams. The objective...