A5085858121- Ecology and Vegetation Dynamics Studies
- Rangeland and Wildlife Management
- Forest Ecology and Biodiversity Studies
- Fire effects on ecosystems
- Plant and animal studies
- Forest Management and Policy
- Lichen and fungal ecology
- Animal Ecology and Behavior Studies
- Forest ecology and management
- Species Distribution and Climate Change
- Botany and Plant Ecology Studies
- Land Use and Ecosystem Services
- Aeolian processes and effects
- Botany, Ecology, and Taxonomy Studies
- Wildlife-Road Interactions and Conservation
- Urban Green Space and Health
- American Environmental and Regional History
- Noise Effects and Management
- Wildlife Ecology and Conservation
- Aquatic Ecosystems and Phytoplankton Dynamics
- Biocrusts and Microbial Ecology
- Nematode management and characterization studies
- Tree Root and Stability Studies
- Seed Germination and Physiology
- Fish Ecology and Management Studies
Ohio University
2015-2024
University of Southern Mississippi
1999-2002
Dana-Farber/Harvard Cancer Center
1993-1997
Harvard University
1993-1997
Rutgers, The State University of New Jersey
1987-1993
Bangor University
1986
The understory flora of successional forest in the Delaware/Pennsylvania Piedmont zone (USA) is species poor relative to old regrowth stands region. Impoverishment may reflect (a) limitations on dispersal potential colonists, or (b) unsuitability for establishment. To examine importance dispersal, herb and shrub distributions were surveyed varying age spatial arrangement. In contiguous with species—rich old—regrowth forest, richness declined distance into stands, implying contagion across...
Forest herbs, shrubs, and tree seedlings were censused at five distances from human-generated edges 14 sites in south-eastern Pennsylvania northern Delaware, USA. varied orientation the degree of canopy closure, allowing comparisons vegetation by aspect successional stage. Soil depth pH measured sampling points a subset sites; microclimate data available parallel study. Edge-related pattern was observed overall species composition, distributions 15 individual species. At recently created...
Seeds and fruit of 38 anemochorous species were dropped in still air to simulate their descent under natural conditions. Fall rate lateral distance recorded as indices wind‐borne dispersal capability. Differences fall rates among plumed dependent on interspecific variation diaspore weight plume area, while winged strongly differentiated by contrasting wing shapes. In Acer platanoides Asclepias syriaca , representing architectures, respectively, the range was artificially extended removing...
Non-native plant species are common along roadsides, but presence does not necessarily indicate spread the road axis. Roadsides may serve merely as habitat for a spreading independently of roads. The potential conduit function roads depends on specificity species, its dispersal range relative to spacing in landscape, and importance long- short-range dispersal. We describe demographic model x interaction suggest methods assessing field based results. A limited roadside will be constrained...
Summary Regional distributions of plants could be determined by local dispersal processes or extreme long‐range dispersal. The importance scale was examined comparing regional frequencies 36 forest herbs with predicted generated a dynamic landscape model that only allowed parameterized to land use turnover in south‐eastern Pennsylvania and northern Delaware, USA, for the period 300 years since initial clearance. successfully fleshy fruited ant‐dispersed modern landscape, but failed predict...
SUMMARY (1) Betula lenta is a gap-requiring forest tree depending on wind-borne seed dispersal for discovery of suitable regeneration sites. Modes winter movement and snow conditions required deposition in this species were examined using variety selective traps. Seed fall was monitored during autumn 1985, compared with aspects weather daily basis. Conditions release identified by subjecting catkins to experimental temperature humidity treatments. (2) In natural populations, released...
(...) Historical records indicate that stands had not been tilled or clear-cut for at least 100 years prior to the study. The seed flora was dominated by herbaceous species typical of early successional and disturbed habitats, but generally absent from mature forest community. Seed distributions ranged mildly strongly clustered scale cm 2 samples, local abundance independent litter composition density vegetative stems in adjacent 4 m quadrats.
Summary Spatially explicit landscape models have revealed the importance of spatial arrangement habitat patches in behaviour mobile organisms. Such fail to account for creation and destruction habitat, which may interrupt movement slowly migrating species such as forest herbs. To explore interaction turnover population migration, we present a dynamic model inhabited by dispersing species. The is represented square lattice individual cells be either or non‐habitat, hypothetical spread among...
The upland shrub community of the New Jersey Pine Barrens maintains strong compositional and structural stability despite frequent low‐intensity fires. To determine mechanisms by which individual species respond to fire, regrowth vegetation was monitored for 3 years after fire at a burned site, nearby site that had not been burned. At both sites, experimental treatments simulated various physical aspects including clipping stems, removal leaf litter, application fertilizer. Both were...
In the last 350 years, forests of eastern North America have experienced widespread clearance and regrowth with local variation in timing extent determined by patterns human land use. This paper describes history forest hinterland a large city (Wilmington, Delaware) surrounded fertile soils having access to navigable estuary. Forests were cleared between 1650 1780 accommodate shifting cultivation cereal crops provide fuelwood for nearby cities. Proximity urban markets supported vigorous...
Abstract Aim Historical land use in eastern North America and much of Europe has created a mosaic successional forest stands widely varying age. An estimate the rate community development would allow conservation value individual to be assessed. We herb secondary forests our region, extent which physical gradients determine distributions. Location Second‐growth Appalachian Oak section Central Hardwoods Region, southeastern Ohio, USA. Methods Thirty‐five plots were surveyed old (82–193 years)...
Abstract Aim The assembly of a forest flora on sites abandoned from agriculture is potentially limited by the physical and chemical suitability soils. This paper describes post‐agricultural development soil in deciduous to gauge its importance limiting second‐growth flora. Location Northern Delaware south‐eastern Pennsylvania, USA. Methods A chronosequence 99 was assembled Piedmont region. Stand age ranged 0–20 > 100 years since canopy closure, as determined historical aerial photographs....
Abstract Aim The greatest biodiversity impact of non‐native plant species is caused by rapid expansion colonist populations. Unfortunately, invasion has rarely been documented in real time at a population scale, and demographic mechanisms remain unclear. Our goal to describe real‐time populations, using channelled diffusion as null model. Location study examined three populations the invasive annual grass Microstegium vimineum mature second‐growth forests south‐eastern Ohio nearby West...