Peter S. White

• PhD, Dartmouth College
• Professor at University of North Carolina at Chapel Hill

The earth's forests are havens of nature supporting a diversity of life. Shaped by climate and geography, these vast and dynamic wooded spaces offer unique ecosystems that shelter complex and interdependent webs of flora, fungi, and animals. The World Atlas of Trees and Forests offers a beautiful introduction to what forests are, how they work, how...

Abstract Nonnative European earthworms are invading hardwood forests of the Chippewa National Forest, MN. While effects on plant communities at the leading edge of invasion have been studied, little is known about longer‐term effects of invasive earthworms. We applied a model using historic O‐horizon soil thickness and a chronosequence approach to...

Non-native European earthworms are invading hardwood forests in the Chippewa National Forest, MN. We applied a model using historic O-horizon soil thickness to classify 41 hardwood sites in the Chippewa National Forest as “long-term wormed” (wormed during the 1989-1996 and 2017 sampling period), “short-term wormed” (unwormed during the 1989-1996 sa...

Blue is a favored color of many humans. While blue skies and oceans are a common visual experience, this color is less frequently observed in flowers. We first review how blue has been important in human culture, and thus how our perception of blue has likely influenced the way of scientifically evaluating signals produced in nature, including appr...

Over the last century, nonnative earthworms have invaded forests of the Great Lakes region of North America. Although a growing body of scientific research has documented short-term changes associated with invasive earthworms, there is little research describing the effects of invasive earthworms over multiple decades. To investigate the long-term...

We propose four postulates as the minimum set of logical propositions necessary for a theory of pulse dynamics and disturbance in ecosystems: (1) resource dynamics characterizes the magnitude, rate, and duration of resource change caused by pulse events, including the continuing changes in resources that are the result of abiotic and biotic process...

In the southern Appalachian Mountains, compositions, structures, and dynamics of forest communities vary across steep topographic gradients, such as elevation and slope aspect, position on slope, steepness, and slope shape (Whittaker 1956). For instance, in mesic sites, the forest transitions across elevations from lower elevation cove hardwoods an...

Ongoing urban development has significant effects on ecosystems, including changes to land cover, environmental conditions, and species’ distributions. These various impacts may have opposing or interacting effects on plant communities, making it difficult to predict how plant biodiversity will respond to urban development. A commonly cited concept...

Aim Urbanization alters local environmental conditions and the ability of species to disperse between remnant habitat patches within the urban matrix. Nonetheless, despite the ongoing growth of urban areas worldwide, few studies have investigated the relative importance of dispersal and local environmental conditions for influencing species composi...

Questions Can forest structure significantly predict tree species diversity in the forests of the North Carolina Piedmont? If so, which structural attributes are most correlated with it, and how effective are they when used in concert in a generalized predictive model of tree species diversity? Location North Carolina Piedmont, USA . Methods Usin...

Community theory proposes that the taxonomic diversity and characteristics, or traits, of the trees found within a particular forest community is a function of both the productivity and disturbance history of that community. The theory also predicts that niche differentiation to the conditions caused by disturbance is strongest on productive sites...

When Great Smoky Mountains National Park (GSMNP) was placed under strict protection in 1934, about 20 % of the landscape was old-growth forest that had never been logged or farmed, and about 80 % was second growth recovering from logging and settlement. We might expect that the structure of GSMNP’s old-growth forests today would capture the natural...

Throughout the eastern deciduous forest (EDF) region, disturbances, including fire, wind storms, and landslides, interweave with complex topography and vegetation history to produce a mosaic of forest types and ages. Forest composition and dynamics following disturbance can depend on the interaction of plant traits related to resource capture, rege...

Significance Around the globe, climate warming is increasing the dominance of warm-adapted species—a process described as “thermophilization.” However, thermophilization often lags behind warming of the climate itself, with some recent studies showing no response at all. Using a unique database of more than 1,400 resurveyed vegetation plots in fore...

Conservation ethics have been based on 2 philosophical value systems: extrinsic value (defined broadly to include all values that derive from something external to the thing valued) and intrinsic value. Valuing biological diversity on the basis of an extrinsic value system is problematic because measurement is often difficult; extrinsic value chang...

Aldo Leopold, in “The Land Ethic,” made 2 important contributions to conservation ethics: he emphasized the community and ecosystem levels of organization and he explicitly included people as members of the biotic community. Leopold's writings remain eloquent, inspirational, and influential, but the ideas he describes are inherently complex, and ec...

Background/Question/Methods Wind disturbance can cause patches of major change in forest vegetation structure due to loss in tree basal area and canopy cover. This can lead to a rapid change in diversity of the forest floor due to increased light penetration and soil disturbance from tip-up mounds. Ruderal and light-dependent woody species may ta...

Background/Question/Methods Understanding the ecological processes operating within cities is becoming increasingly important. While many studies have investigated the effects of habitat loss and fragmentation on natural populations and communities, fewer have addressed the impacts of altered environmental conditions associated with urbanization,...

Though a number of studies have focused on the factors that shape the structure and dynamics of temperate forests, little is known about whether these factors vary with spatial scale. In this study we investigated compositional and structural patterns of forests across three spatial scales (plot, local assemblages and regions) in northeast China an...

Background/Question/Methods Disturbances beyond a threshold of intensity or frequency can initiate or maintain early successional vegetation. Throughout the southern Appalachian mountains and more broadly the eastern U.S., disturbances, including fire, wind storms, and landslides, interweave with complex topography and vegetation history to produc...

We examined the effect of position with respect to the soil surface, species, and piece size on the decomposition rate of fine woody debris (< 15 cm diameter) in a North Carolina forest disturbed by hurricane. To examine year-to-year trends, pieces of two species (Carya tomentosa ((Lam.) Nutt.) and Quercus alba (Lam.)) in four size classes were pla...

Largely a legacy of stand-replacing human disturbances, today’s central hardwood forests exhibit a narrower range of stand ages and structures than those in the presettlement landscape. Although natural disturbance types and frequencies vary within the region, large stand-replacing natural disturbances have always been infrequent; typical return in...

We analyzed a naturalized population of Magnolia grandiflora L. occurring north of its native range in a temperate deciduous forest of the North Carolina piedmont. The population was likely expanding, based on its size-class distribution; however, it had not reached a reproductive size or age. The maximum size of established stems was 9.8 cm dbh an...

The response of old-growth spruce – fir vegetation to environmental gradients was investigated using 1930s plot data from the Great Smoky Mountains. Gradients related to forest composition and position of the ecotone with the deciduous forest were identified using canonical correspondence analysis (CCA) and their role in vegetation response to clim...

Spatially small canopy gaps dominated the natural disturbance regime of old-growth spruce–fir forests in the Great Smoky Mountains, North Carolina and Tennessee. New gaps ≤200 m2 in size were formed with a frequency of 0.006 to 0.009/year and the 1- to 10-year age class of these gaps covered an estimated 6 to 17% of the study area (depending on cal...

Aboveground biomass and aboveground net primary production (ANPP) were determined for leaf, branch, and bole compartments of cove forests in the Great Smoky Mountains, Tennessee. The sample plots included young stands (42-63 years following agricultural abandonment) and old stands with no history of logging or catastrophic fire. Tree species, diame...

The major challenge to stewardship of protected areas is to decide where, when, and how to intervene in physical and biological processes, to conserve what we value in these places. To make such decisions, planners and managers must articulate more clearly the purposes of parks, what is valued, and what needs to be sustained. A key aim for conserva...

The reintroduction of pre-European fire regimes has allowed the entry of many invasive plant species into fire-dependant ecosystems of North America. However, the environmental factors that favor the post-fire establishment of these species across complex landscapes are not well understood and the initial establishment of invasive species does not...

growing scientifi c evidence of the negative impacts . Our analyses of current studies and water-quality data from WV streams revealed serious environmental impacts that mitigation practices successfully Published studies human health impacts.

Damage to ecosystems and threats to human health and the lack of effective mitigation require new approaches to mining regulation.

Question: Can a new cost-distance model help us to evaluate the potential for accessibility bias in ecological observations? How much accessibility bias is present in the vegetation monitoring plots accumulated over the last three decades in Great Smoky Mountains National Park? Location: Great Smoky Mountains National Park, North Carolina and Tenne...

Large ungulates are an important driver of plant community composition and structure. In eastern North America, white-tailed deer (Odocoileus virginianus) thrive in agricultural mosaics and fragmented forested landscapes, at times reaching unprecedented densities. Nevertheless, few long-term data sets are available that allow an assessment of the l...

Patch dynamics, tree injury and mortality, and coarse woody detritus were quantified to examine the ecological impacts of Hurricane Fran on an oak-hickory-pine forest near Chapel Hill, NC. Data from long-term vegetation plots (1990–1997) and aerial photographs (1998) indicated that this 1996 storm caused patchy disturbance of intermediate severity...

Species composition patterns and vegetation-environment relationships were quantified for high-elevation rock outcrops of the Southern Appalachian Mountains, an infrequent and insular habitat in a forested landscape. Outcrops occur over a wide geographic range encompassing extensive variation in both geology and climate. Geographic-scale factors in...

Northeast (NE) China covers three climatic zones and contains all the major forest types of NE Asia. We sampled 108 forest plots in six nature reserves across NE China to examine the influence of climate and local factors (canopy seasonality, successional stage, topography and forest structure) on geographic patterns of plant richness. We analyzed...

There must have been plenty of them about, growing up quietly and inoffensively, with nobody taking any particular notice of them…. And so the one in our garden continued its growth peacefully, as did thousands like it in neglected spots all over the world…. It was some little time later that the first one picked up its roots and walked. John Wyndh...

Background/Question/Methods Over the past decade, prescribed burning has been increasingly used to reintroduce native fire regimes and restore fire-dependent communities. However, in contemporary landscapes the reintroduction of fire often brings unintended consequences, such as the invasion of exotic species. In the southern Appalachians, Paulow...

Beta-diversity, the change in species composition between places, is a critical but poorly understood component of biological diversity. Patterns of beta-diversity provide information central to many ecological and evolutionary questions, as well as to conservation planning. Yet beta-diversity is rarely studied across large extents, and the degree...

Correlations between Beta-Diversity (βsim-d) and Two Environmental Variables (Elevation and Number of Biome Edges of Grid Cells) (81 KB PDF)

Average Nearest-Neighbor Beta-Diversity of Amphibians, Birds, and Mammals Mapped Continuously across the Continental Western Hemisphere Average nearest-neighbor beta-diversity (βsim) values are divided into 20 quantiles, represented by warm (higher βsim) to cool (lower βsim) colors. The scale accompanying the color ramp shows minimum, first quartil...

Correlations in Average Nearest-Neighbor Beta-Diversity (βsim) within the Western Hemisphere, Nearctic Realm, and Neotropical Realm (81 KB PDF)

Scatter Plots Showing Relationships between Beta-Diversity and Two Environmental Variables (Elevation and Number of Biome Edges within Grid Cells) For each panel, untransformed (left plots) and transformed (right plots) values of βsim-d (y-axis) against either grid cell elevation (x-axis, upper plots) or number of biome edges within grid cell (x-ax...

Bird Beta-Diversity Based on Both Breeding and Non-Breeding Ranges Beta-diversity (βsim-d) values are divided into 20 quantiles, represented by warm (higher βsim-d) to cool (lower βsim-d) colors. The scale accompanying the color ramp shows minimum, first quartile, median, third quartile, and maximum values of βsim-d. (210 KB PDF)

Mean Elevation and Mean Number of Biome Edges for Sets of the Highest 2.5% and Lowest 2.5% of Beta-Diversity Grid Cells (56 KB PDF)

We present a data set collected in 1989 of vascular plant occurrences in overlapping grids of nested plots in the Oosting Natural Area of the Duke Forest, Orange County, North Carolina, USA. The purpose of these data is to allow the study of vascular plant biodiversity at multiple spatial scales, in terms of both grain and extent. There are eight d...

Conclusions from past studies on the roles that historical and regional factors and contemporary and ecological factors have played in regulating large-scale patterns of species richness have been controversial. Conflicting past results were likely affected by differences in the range of environments analyzed and the scales of observation. Eastern...

Large, infrequent fires (LIFs) can have substantial impacts on both ecosystems and the economy. To better understand LIFs and to better predict the effects of human management and climate change on their occurrence, we must first determine the factors that produce them. Here, we review local and regional literature investigating the drivers of LIFs...

Because of the high calcium content of its foliage, Cornus florida (flowering dogwood) has been described as a calcium "pump" that draws calcium from deeper mineral soil and enriches surface soil horizons. However, over the last two decades an exotic fungal disease (dogwood anthracnose, Discula destructiva) has decimated populations of this once-co...

We studied the effects of logging history, topography, and potential insolation on the lower-elevation limit of existing spruce-fir forest in Great Smoky Mountains National Park (GRSM). Dummy-variable regression, analysis of variance, and classification trees were applied to environmental data within a geographic information system framework. The e...

Beta-diversity, the change in species composition between places, is a critical but poorly understood component of biological diversity. Patterns of beta-diversity provide information central to many ecological and evolutionary questions, as well as to conservation planning. Yet beta-diversity is rarely studied across large extents, and the degree...

We present a general structural carbon—nutrient balance hypothesis parallel to Bryant et al.'s defensive chemistry hypothesis. Our hypothesis suggests that because herb species require a lower investment of carbon per unit length of stem than do woody plants, herbs should be at a competitive advantage where the leaf area of plants in the ground lay...

In the summer of 1997 these questions were lamented by a handful of U.S. National Park Service (NPS), U.S. Geological Survey (USGS), and university professionals involved in natural resources stewardship and science at Great Smoky Mountains Na- tional Park. It was noted that over the years we were increasingly being forced to make many resource-imp...

The diversity of a region reflects both local diversity and the turnover of species (beta diversity) between areas. The angiosperm flora of eastern Asia (EAS) is roughly twice as rich as that of eastern North America (ENA), in spite of similar area and climate. Using province/state-level angiosperm species floras, we calculated beta diversity as th...

Although the rate that species accumulate with area has long been regarded as an important component of fine-scale community structure and several studies have examined this rate in meta-analyses, few if any studies have systematically examined fine-scale species-area relationships using a consistent survey protocol over a large region. We examined...

The paradigm of flux poses a challenge to environmental ethics: since nature is in flux, there appears to be no reference state by which to evaluate human caused change. If ecosystems are dynamic and long term climatic instability causes continued change, it is easy to view human caused changes as just another and analogous source of change. A rela...

Two outstanding papers on restoration and succession are briefly discussed as model papers for the type of research papers Appl. Veg.Sci. should publish. The paper on restoration concentrates on the introduction of hay to a site in order to speed up the introduction of target species. The paper on succession discusses the importance of plant coloni...

The greater number of plant species in temperate eastern Asia compared to eastern North America has been ascribed to both local environment and regional characteristics, but the relative contributions of each have not been resolved. In this analysis, we related species richness of flowering plants in mesoscale floras (<104 km2) dominated by tempera...

Biological invasions are increasingly recognized as a key problem for the conservation of biological diversity. However, the scientific recognition that some species, when introduced outside their native range, cause a decline in indigenous species, goes back to at least the writings of Charles Darwin. In the 1950s another British biologist, Charle...

Ecological explanations of the distributions of living things rest on two general conceptual pillars: the niche difference model and the model of spatial and temporal constraint. Both models suggest the underlying importance of spatial distance as a simple correlate of biological pattern. In this essay we discuss five key, but seemingly disparate,...

Piaget’s theory of cognitive development serves as a basis for a comparative analysis of middle school students’ understanding of classification in the physical and digital library. Attention is also given to student comprehension of scientific classification. Results of this pilot study show that although participants had good comprehension of cla...

Remeasurement of woody vegetation on permanent plots in western Great Smoky Mountains National Park indicated that understory composition and dominance have changed over the past two decades (between 1977-1979 and 1995-2000). We observed heavy mortality of Cornus Florida L., likely as a result of infection by Discula destructive Redlin, a destructi...

A substantial body of literature has accumulated on the topic of the estimation of species richness by extrapolation. However, most of these methods rely on an objective sampling of nature. This condition is difficult to meet and seldom achieved for large regions. Furthermore, scientists conducting biological surveys often already have preliminary...

We used remote sensing and a geographic information system to model the distribution of evergreen shrub communities, called ‘heath balds’, in the Great Smoky Mountains, North Carolina and Tennessee, USA. The 421 heath balds averaged 1.8 ha in size and covered 0.3% of the landscape. They reached their greatest importance on upper slopes (92% had rel...

Studies of disturbance have a long tradition in vegetation ecology (Cooper 1926; Raup 1941; White 1979) and have increased lly during the last 30 years (Dayton 1971; Heinselman 1973; Levin and Paine 1974; Borman and Likens 1979; Sousa 1979a,b, 1984; Pickett 1980; Pickett and White 1985; Van der Maarel 1993; Bornette and Amoros 1996; Paine et al. 19...

This issue of Natural Areas Journal focuses on ecology and management of rare plants of the southeastern United States. This region lies mostly south of the Wisconsin glacial boundary and includes sections of the Coastal Plain, Piedmont, and Appalachian Highlands Physiographic Provinces. Lack of glaciation might have helped concentrate rare plants...

Ecological assessments often begin with the inventory of a site’s biological resources and culminate in the generation of a static, two-dimensional map or other fixed report of present site conditions. Using this approach, we may fail to appreciate the short- and long-term dynamics of the populations and ecosystems that we are assessing. Spatial an...

We document post-fire succession on xeric sites in the southern Appalachian Mountains, USA and assess effects of 20th century reduction in fire frequency on vegetation structure and composition. Successional studies over 18 yr on permanent plots that had burned in 1976–1977 indicate that tree mortality and vegetation response varied with fuel load...

The Plant Information Center is a partnership of the North Carolina Botanical Garden, Unviersity of North Carolina (UNC) Herbarium, UNC School of Information and Library Science, McDougle Middle School, and Orange County Public Library. The intent of the Project is to connect the research community and the general public (including school children)...