A5074352131- Plant Water Relations and Carbon Dynamics
- Plant responses to elevated CO2
- Ecology and Vegetation Dynamics Studies
- Forest ecology and management
- Remote Sensing in Agriculture
- Atmospheric chemistry and aerosols
- Fire effects on ecosystems
- Seedling growth and survival studies
- Leaf Properties and Growth Measurement
- Tree-ring climate responses
- Forest Insect Ecology and Management
- Forest Management and Policy
- Hydrology and Watershed Management Studies
- Bioenergy crop production and management
- Plant Pathogens and Fungal Diseases
- Plant and animal studies
- Rangeland and Wildlife Management
- Species Distribution and Climate Change
- Spectroscopy and Chemometric Analyses
- Remote Sensing and LiDAR Applications
- Plant Physiology and Cultivation Studies
- Insect and Pesticide Research
- Forest Ecology and Biodiversity Studies
- Wildlife Ecology and Conservation
- Berry genetics and cultivation research
University of New Mexico
2022-2025
University of Wisconsin–Madison
2015-2024
University of New Mexico Hospital
2022
North-West University
2012-2013
Linde (United States)
2005
University of Illinois Urbana-Champaign
2001
Illinois Department of Natural Resources
2001
Minnesota Department of Natural Resources
1989-1997
University of Minnesota
1989-1997
Researchers from a number of disciplines have long sought the ability to estimate functional attributes plant canopies, such as photosynthetic capacity, using remotely sensed data. To date, however, this goal has not been fully realized. In study, fresh-leaf reflectance spectroscopy (λ=450–2500 nm) and partial least-squares regression (PLSR) analysis were used key determinants capacity—namely maximum rates RuBP carboxylation (Vcmax) regeneration (Jmax)—measured with standard gas exchange...
Summary The temperature response of photosynthesis is one the key factors determining predicted responses to warming in global vegetation models ( GVM s). may vary geographically, owing genetic adaptation climate, and temporally, as a result acclimation changes ambient temperature. Our goal was develop robust quantitative model representing photosynthetic responses. We quantified modelled mechanisms responsible for using dataset CO 2 curves, including data from 141 C 3 species tropical...
Summary Foliar functional traits are widely used to characterize leaf and canopy properties that drive ecosystem processes infer physiological in Earth system models. Imaging spectroscopy provides great potential map foliar continuous variation diversity, but few studies have demonstrated consistent methods for mapping multiple across biomes. With airborne imaging data field from 19 sites, we developed trait models using partial least squares regression, mapped 26 seven NEON (National...
Summary The impacts of elevated atmospheric CO 2 and/or O 3 have been examined over 4 years using an open‐air exposure system in aggrading northern temperate forest containing two different functional groups (the indeterminate, pioneer, ‐sensitive species Trembling Aspen, Populus tremuloides and Paper Birch, Betula papyrifera , the determinate, late successional, ‐tolerant Sugar Maple, Acer saccharum ). responses to these interacting greenhouse gases remarkably consistent pure Aspen stands...
In order to understand better the ecophysiological differences among competing species that might influence competitive interactions after, or in absence of, fire, we examined response fire of four sympatric woody found intermediate—sized gaps a 3—yr—old mixed oak forest central Wisconsin. Selected blocks were burned April 1987 by low—intensity controlled surface fire. The had significant effects during following growing season on community structure, foliar nutrient concentrations, and...
Leaf mass per area (LMA) is a key plant trait, reflecting tradeoffs between leaf photosynthetic function, longevity, and structural investment. Capturing spatial temporal variability in LMA has been long-standing goal of ecological research an essential component for advancing Earth system models. Despite the substantial variation within across Earth's biomes, efficient, globally generalizable approach to predict still lacking. We explored capacity from spectra much global trait space, with...
Abstract The Chequamegon Heterogeneous Ecosystem Energy-Balance Study Enabled by a High-Density Extensive Array of Detectors 2019 (CHEESEHEAD19) is an ongoing National Science Foundation project based on intensive field campaign that occurred from June to October 2019. purpose the study examine how atmospheric boundary layer (ABL) responds spatial heterogeneity in surface energy fluxes. One main objectives test whether lack balance closure measured eddy covariance (EC) towers related...
N acquisition often lags behind accelerated C gain in plants exposed to CO2-enriched atmospheres. To help resolve the causes of this lag, we considered its possible link with stomatal closure, a common first-order response elevated CO2 that can decrease transpiration. Specifically, tested hypothesis declines transpiration, and hence mass flow soil solution, delivery mobile root thereby limit plant acquisition. We altered transpiration by manipulating relative humidity (RH) atmospheric [CO2]....
Summary • The role of water stress in the initiation collar rot by Sphaeropsis sapinea asymptomatically colonized Pinus resinosa seedlings is reported. Mortality and frequency identification pathogen was quantified for subjected to different regimes or watering regime–fungicide (benomyl) combinations glasshouse experiments. In experiment 1, seedling mortality ranged from 8% repeatedly watered 50% those driest regime; data analysis indicated a high probability that not independent regime....
• Costs of defense are thought to maintain genetic variations in the expression within plant populations. As with many species, aspen exhibits considerable variation allocation secondary metabolites. This study examined independent and interactive effects genotype, soil fertility belowground competition on defensive chemistry growth trembling (Populus tremuloides). Four genotypes were grown high low fertility, without root competition. Physiological, morphological allocational determinants...
Technological advances during the past several decades have greatly enhanced our ability to measure leaf photosynthesis virtually anywhere and under any condition. Associated with resulting proliferation of gas-exchange data is a lingering uncertainty regarding importance such measurements when it comes explaining intrinsic causes plant growth variation. Accordingly, in this paper we rely on compilation address following questions: from both statistical mechanistic standpoints, how closely...
1 Herbivore damage can select for tolerance in plant populations where genetic variation exists. The causes underlying are not fully resolved. We assessed the importance of two potential mechanisms by examining its relationship with leaf photosynthetic rate and relative biomass allocation across organs. 2 monitored responses 12 aspen (Populus tremuloides) genotypes, grown a common garden under levels nutrient availability, to defoliation successive seasons. Tolerance each genotype was...
Common gardens were established along a approximately 900 km latitudinal transect to examine factors limiting geographical distributions of boreal and temperate tree species in eastern North America. Boreal representatives trembling aspen (Populus tremuloides Michx.) paper birch (Betula papyrifera Marsh.), while cottonwood deltoides Bartr ex. Marsh var. deltoides) sweetgum (Liquidambar styraciflua L.). The compared with respect adjustments leaf photosynthetic metabolism the transect,...
Concurrent measurement of multiple foliar traits to assess the full range trade-offs among and within taxa across broad environmental gradients is limited. Leaf spectroscopy can quantify a wide functional traits, enabling assessment interrelationships with environment. We analyzed leaf trait measurements from 32 sites along eco-climatic gradient encompassed by US National Ecological Observatory Network (NEON). explored relationships 14 1103 individuals species, factors. Across all species...
Assumed representative center‐of‐stand measurements are typical inputs to models that scale forest transpiration stand and regional extents. These do not consider gradients in at boundaries or along moisture therefore potentially bias the large‐scale estimates. We measured half‐hourly sap flux ( J S ) for 173 trees a spatially explicit cyclic sampling design across topographically controlled gradient between forested wetland upland northern Wisconsin. Our analyses focused on three dominant...