A5091192733- Fire effects on ecosystems
- Plant Water Relations and Carbon Dynamics
- Forest ecology and management
- Atmospheric and Environmental Gas Dynamics
- Remote Sensing and LiDAR Applications
- Plant responses to elevated CO2
- Atmospheric chemistry and aerosols
- Soil and Water Nutrient Dynamics
- Forest Management and Policy
- Ecology and Vegetation Dynamics Studies
- Wind and Air Flow Studies
- Soil Carbon and Nitrogen Dynamics
- Rangeland and Wildlife Management
- Tree-ring climate responses
- Climate change and permafrost
- Fire dynamics and safety research
- Meteorological Phenomena and Simulations
- Peatlands and Wetlands Ecology
- Vehicle emissions and performance
- Hydrology and Watershed Management Studies
- Land Use and Ecosystem Services
- Mine drainage and remediation techniques
- Landslides and related hazards
- Urban Heat Island Mitigation
- Aquatic Invertebrate Ecology and Behavior
Northern Research Station
2010-2022
US Forest Service
2008-2022
University of Delaware
2021-2022
Michigan State University
2019
United States Department of Agriculture
2008-2016
North Carolina State University
2014
University of Maine
2014
University of Edinburgh
2014
Agricultural Research Service
2009-2011
University of California, Berkeley
1999
The emerging discipline of urban ecology is shifting focus from ecological processes embedded within cities to integrative studies large areas as biophysical-social complexes. Yet this lacks a theory. Results the Baltimore Ecosystem Study, part Long Term Ecological Research Network, expose new assumptions and test existing about ecosystems. findings suggest broader range structural functional relationships than often assumed for systems. We address between social status awareness...
This paper reports results of a study designed to examine the control that soil temperature exerts on processes associated with nutrient flux, and in turn, tree nutrition interior Alaska black spruce ecosystems. Approximately 50 m 2 forest floor 140-year-old ecosystem, which had developed permafrost, was heated 8–10 °C above ambient temperature. perturbation amounted approximately 1589 degree-day seasonal heat sum (above 0 °C), 1026 degree-days total 563 degree-days. The floor, surface 5 cm...
Abstract Invasive insects can impact ecosystem functioning by altering carbon, nutrient, and hydrologic cycles. In this study, we used eddy covariance to measure net CO 2 exchange with the atmosphere (NEE), biometric measurements characterize productivity (NEP) in oak‐ pine‐dominated forests that were defoliated Gypsy moth ( Lymantria dispar L.) New Jersey Pine Barrens. Three years of data compare C dynamics; 2005 minimal defoliation, 2006 partial defoliation canopy understory a mixed stand,...
We compared estimates of net primary production (NPP) from the MODIS satellite with a forest ecosystem process model (PnET-CN) and inventory analysis (FIA) data for types mid-Atlantic region United States. The regional means were similar three methods dominant oak-hickory forests in region. However, underestimated NPP less-dominant northern hardwood overestimated coniferous forests. Causes inaccurate by (1) an aggregated classification parameterization diverse deciduous different climatic...
The photosynthetic capacity of different needle age-classes black spruce (Piceamariana (Mill) B.S.P.) was studied using 14 C labelling on whole branches at a site near Fairbanks, Alaska. Black had highest rates in the 1-year-old tissue with four most current showing similar high before declining age. Older needles were found to maintain 40% maximum after 13 seasons. Highest level nitrogen first eight maintaining levels 70% values oldest needles. Phosphorus much higher gradual decline value...
Abstract Urban facets—the walls, roofs, and ground in built-up terrain—are often conceptualized as homogeneous surfaces, despite the obvious variability composition material properties of urban fabric at subfacet scale. This study focuses on understanding influence this heterogeneity, associated different properties, surface energy budget. The Princeton Canopy Model, which was developed with ability to capture variability, is evaluated sites various building densities then applied simulate...
Accounting for both climate change and natural disturbances—which typically result in greenhouse gas emissions—is necessary to begin managing forest carbon sequestration. Gaining a complete understanding of dynamics is, however, challenging systems characterized by historic over‐utilization, diverse soils tree species, frequent disturbance. In order elucidate the cascading effects potential on such systems, we projected dynamics, including soil changes, shifts species composition as...
Abstract Low‐intensity wildland fires occurring beneath forest canopies can result in particularly adverse local air‐quality conditions. Ambient and fire‐induced turbulent circulations play a substantial role the transport dispersion of smoke during these fire events. Recent situ measurements fire–atmosphere interactions low‐intensity have provided new insight into structure turbulence regimes how overstory vegetation affect horizontal vertical smoke. In this paper, we provide summary key...
Disturbance regimes within temperate forests can significantly impact carbon cycling. Additionally, projected climate change in combination with multiple, interacting disturbance effects may disrupt the capacity of to act as sinks at large spatial and temporal scales. We used a spatially explicit forest succession model, LANDIS-II, model change, gypsy moth (Lymantria dispar L.) defoliation, wildfire on C dynamics New Jersey Pine Barrens over next century. Climate scenarios were simulated...
Abstract Ambient and fire-induced atmospheric turbulence in the vicinity of wildland fires can affect behavior those dispersion smoke. The presence forest overstory vegetation further complicate evolution local regimes their interaction with spreading smoke plumes. Previous observational studies fire events forested environments have shown that energy anisotropy line exhibit temporal spatial variability influenced by vegetation. This study builds on previous to examine during two...
Dry deposition determinations, along with wet and throughfall (TF) measurements, at a spruce fir forest in central Maine were used to estimate the effect of atmospherically deposited nitrogen (N) uptake on carbon storage. Using nitric acid particulate N as well TF ammonium nitrate data, growing season (May‐October) net canopy atmospheric, predominantly anthropogenic, was found be 1‐5 kg ha −1 . The ratio that recycled root (10‐30 during season) suggests substantial modification cycle this...
Abstract Eucalyptus L'Héritier (Myrtaceae: Leptospermoideae) species are native to the Austro‐Malaysian region, but have been widely planted in temperate and subtropical regions around world. In most where imported, Longhorned Borer ( Phoracantha semipunctata F.) (Coleoptera: Cerambycidae) has accidently introduced. Larvae of beetle bore through bark mine along cambium stressed trees, usually killing their host. We report here relative susceptibilities 12 two mixed‐species plantations...
Seeds from two full-sib families of ponderosa pine (Pinus ponderosa) with known differences in growth rates were germinated and grown an ambient (350 micro l l(-1)) or elevated (700 CO(2) concentration. Gas exchange at both concentrations was measured 1, 6, 39, 112 days after the seed coat shed. Initial stimulation rate (CER) by large (> 100%). On Day CER seedlings significantly lower than CO(2), indicating physiological adjustment exposed to CO(2). Physiological acclimation complete 39 when...
Abstract To assess what difference it might make to include spatially defined estimates of foliar nitrogen in the regional application a forest ecosystem model (PnET-II), we composed predictions wood production from extensive ground-based inventory analysis data across Mid-Atlantic region. Spatial variation N concentration was assigned based on correlation with mean July temperature for deciduous forests and latitude coniferous forests. Although slight observed conifers had little effect...