A5066193570- Plant Water Relations and Carbon Dynamics
- Forest ecology and management
- Fire effects on ecosystems
- Peatlands and Wetlands Ecology
- Tree-ring climate responses
- Atmospheric and Environmental Gas Dynamics
- Hydrology and Watershed Management Studies
- Soil Carbon and Nitrogen Dynamics
- Coastal wetland ecosystem dynamics
- Hydrocarbon exploration and reservoir analysis
- Forest Management and Policy
- Cryospheric studies and observations
- Geology and Paleoclimatology Research
- Climate variability and models
- Plant responses to elevated CO2
- Plant Ecology and Soil Science
- Ecology and Vegetation Dynamics Studies
- Soil and Unsaturated Flow
- Climate change and permafrost
- Energy Load and Power Forecasting
- Hydrology and Drought Analysis
- Soil Geostatistics and Mapping
- Indigenous Studies and Ecology
- Rangeland and Wildlife Management
- Aeolian processes and effects
University of Waterloo
2019-2023
McMaster University
2008-2022
James Hutton Institute
2017
Clark University
2013-2014
Max Planck Institute for Biogeochemistry
2010-2014
Most North American temperate forests are plantation or regrowth forests, which actively managed. These in different stages of their growth cycles and ability to sequester atmospheric carbon is affected by extreme weather events. In this study, the impact heat drought events on sequestration an age-sequence (80, 45, 17 years as 2019) eastern white pine (Pinus strobus L.) southern Ontario, Canada was examined using eddy covariance flux measurements from 2003 2019.Over 17-year study period,...
Abstract This study analysed age‐related water‐use dynamics across three temperate conifer forest plantations (aged 11, 39 and 74 years, as of 2013, henceforth referred to TP02, TP74 TP39, respectively, where the last two digits represent year planting) in southern Ontario, Canada, from 2008 2013. Eddy covariance‐measured mean evapotranspiration over growing season (April–October) was 438 ± 19, 392 19 323 25 mm at respectively. Daytime bulk surface conductance highest most variable TP39 site...
Abstract The effects of early growing season droughts on water and carbon balances in conifer forests are poorly understood. In this study, the response canopy transpiration ( E c ) growth rates to reduced precipitation input during was evaluated a 70‐year old temperate white pine Pinus strobus L.) plantation forest, Southern Ontario, Canada. order induce drought, 20 × m throughfall exclusion setup established. Throughfall excluded from 1 April 3 July 2009. During period, 270 mm rainfall...
Abstract Clearcutting and other forest disturbances perturb carbon, water, energy balances in significant ways, with corresponding influences on Earth's climate system through biogeochemical biogeophysical effects. Observations are needed to quantify the precise changes these as they vary across diverse of different types, severities, various ecosystem type settings. This study combines eddy covariance micrometeorological measurements surface‐atmosphere exchanges vegetation inventories...
Peatlands provide important ecosystem services including carbon storage and biodiversity conservation. Remote sensing shows potential for monitoring peatlands, but most off-the-shelf data products are developed unsaturated environments it is unclear how well they can perform in peatland ecosystems. Sphagnum moss an genus with specific characteristics which affect spectral reflectance, we hypothesized that the prevalence of a could signature area. This article combines results from both...
The influences of soil water supply and atmospheric demand on transpiration were studied to gain insight into the physical mechanisms limiting forest use within broader context total canopy loss atmosphere. Evaporation from forests ( E ) can be partitioned in four main source components: c ), understorey u evaporation s intercepted I ). usually make up most . estimated sap flow measurements modeled estimates compared with eddy covariance measured values quantify components above flux...
Abstract. The annual carbon and water dynamics of two eastern North American temperate forests were compared over a 6-year period from 2012 to 2017. geographic location, forest age, soil, climate similar between the stands; however, stand composition varied in terms tree leaf-retention shape strategy: one was deciduous broadleaf forest, while other an evergreen needleleaf forest. mean net ecosystem productivity (NEP) coniferous slightly higher more variable (218±109 g C m−2 yr−1) that NEP...
Abstract Forests are major terrestrial carbon (C) sinks and play a crucial role in climate change mitigation. Despite extensive studies on forest C sequestration, the relationship between seasonal uptake its allocation to woody biomass is poorly understood. Here we used novel dendro-anatomical approach investigate relationships variability, uptake, growth an 80 year-old eastern white pine ( Pinus strobus ) plantation Ontario, Canada. We eddy covariance (EC) gross primary productivity (GPP)...
A number of empirical models are used in literature to simulate the response soil respiration (Rs) temperature (Ts). The most widely ones exponential Q 10 model and sigmoid‐shaped Lloyd‐Taylor logistic models. None these applicable across a wide range ecosystems or climates, none allow Rs decrease at high Ts values. Here we present new, more flexible, model, so‐called Gamma which can take on shapes three mentioned above is mathematically flexible enough for values, as dictated by data. We...
Carbon dioxide (CO 2 ) emissions from soil, foliage, and live woody tissue were measured throughout the year in afforested, white pine ( Pinus strobus L.) stands (67, 32, 17, 4 years old as of 2006), growing a northern temperate climate. The data used to estimate annual ecosystem respiration R e) its component fluxes, including foliar, respiration; investigate major environmental factors causing intersite temporal variability observed fluxes; compare chamber‐based e estimates with eddy...
Abstract. This study investigated differences in the magnitude and partitioning of carbon (C) greenhouse gas (GHG) balances an age sequence four white pine (Pinus strobus L.) afforestation stands (7, 20, 35 70 years old as 2009) southern Ontario, Canada. The 4-year (2004–2008) mean annual dioxide (CO2) exchanges, based on biometric eddy covariance data, were combined with 2-year means static chamber measurements methane (CH4) nitrous oxide (N2O) fluxes (2006–2007) dissolved organic (DOC)...
Abstract In eastern North America, many deciduous forest ecosystems grow at the northernmost extent of their geographical ranges, where climate change could aid or impede growth. This region experiences frequent extreme weather conditions, allowing us to study response these forests environmental reflective future climates. Here we determined impact seasonal and annual variations events on carbon (C) uptake capacity an oak‐dominated in southern Ontario, Canada, from 2012 2016. We found that...
Abstract Forest plantations are commonly used to restore the ecological and hydrological functionality of landscapes. In this study, we investigated response a 74‐year‐old pine plantation forest in southern Ontario, Canada selective thinning, wherein 30% trees were harvested winter 2012. Tree‐level ecosystem‐level water fluxes monitored from 2011 2013 using sapflow eddy‐covariance techniques, compared with an adjacent 39‐year‐old that was not thinned. forest, transpiration declined after...
Abstract Mountain regions are an important regulator in the global water cycle through their disproportionate contribution. Often referred to as “Water Towers of World”, mountains contribute 40%–60% world's annual surface flow. Shade is a common feature mountains, where complex terrain cycles land surfaces and out shadows over daily seasonal scales, which can impact use. This study investigated turbulent carbon dioxide (CO 2 ) fluxes during snow‐free period subalpine wetland Canadian Rocky...
Abstract Sphagnum is an important peat‐forming genus, which aids the carbon sequestration of peatlands. sensitive to drought; however, and it uncertain how well can recover from long periods without rainfall. Spectral reflectance be used assess desiccation damage, we also tested whether detect recovery. Different rainfall simulations were applied two species impact drought on function. After 80 days all samples rewetted The included inputs analogous actual precipitation at field site...
Clearcutting a forest ecosystem can result in drastic reduction of stand productivity. Despite the severity this disturbance type, past studies have found that productivity young regenerating stands quickly rebound, approaching mature undisturbed within few years. One obvious reasons is increased leaf area (LA) with each year recovery. However, less reason may be variability species composition and distribution during natural regeneration process. The purpose study was to investigate what...