Marc David Abrams, Ph.D.

Marc David Abrams, Ph.D.

  • Nancy and John Steimer Professor of Agricultural Sciences
  • Professor of Forest Ecology and Physiology
307 Forest Resources Building
University Park, PA 16802

Areas of Expertise

  • Global change ecology



  • B.S., S.U.N.Y. Binghamton (1976)
  • M.S., Michigan State University (1979)
  • Ph.D., Michigan State University (1982)

Academic Interests

Disturbance ecology; old-growth forests; tree physiology; vegetation classification

Affiliated Programs

Graduate faculty, Intercollege Graduate Degree Program in Ecology and Plant Physiology.

Courses Taught

Forest Ecology; Tree Physiology

Professional Affiliation

Editor, Ecology ; Panel Member, National Science Foundation, Division of Environ-mental Biology, Collaborative Research for Undergraduate Institutions (CRUI) Grants; Member, Ecological Society of America Committee on Vegetation Classification

Recent Research/Educational Projects

Dendroecology of Old-growth Forests - A number of undisturbed, old-growth oak and pine forests in the mid-Atlantic have been located and used for detailed analysis of composition, structure, historical development, disturbance history, species recruitment patterns, and future succession. Dominant forest types were for study include white pine, pitch pine, white oak, chestnut oak, and red oak. Prior to European settlement, oak and pine species grew in uneven-aged conditions and experienced recurring understory burning. Fire exclusion during the 20th century appears to be leading to the successional replacement of most oak and pine forest to later successional species, in particular red maple, sugar maple, beech, and blackgum.

Ecophysiological Responses to Interaction Among Light, Site, and Drought - Naturally occurring field plants are invariably affected by multiple environmental interactions, including concurrent stress factors. Seasonal physiology and leaf morphology were monitored in naturally occurring tree species under a variety of ecological conditions in the eastern United States, including high- and low-light environments, burned and unburned plots, and sites of contrasting water relations. In most cases seasonal droughts allowed us to evaluate the impact of multiple stresses or environmental interactions in ecologically contrasting tree species. The results of these studies indicate the wide variation and complexity of responses to environmental interactions in temperate tree species.

Vegetation Classification of Mid-Atlantic Forest Types - The mid-Atlantic region is highly diverse physiographically. This variation produces highly distinct forest types on different physical units. Studies of vegetation classification have been completed for a large number of second-growth hardwood- and conifer-dominated forests in central Pennsylvania, West Virginia, and Virginia. These studies have been successful in relating spatial variation in forest composition and structure to physiographic variation. Temporal variation in these forests has been related to land-use history. Studies of presettlement forest in each region through the use of witness tree data indicate the dramatic changes that have occurred since European settlement.

Selected Publications

Abrams, M. D.  1998.  The red maple paradox.  BioScience 48:355-364.

Abrams, M.D., D.A. Orwig, and T.E. DeMeo. 1995. Dendro-ecological analysis of successional dynamics for a presettlement origin white pine-mixed oak forest in the southern Appalachians, USA. J. of Ecology. 83:123-133.

Abrams, M.D., M.E. Kubiske, and S.A. Mostoller. 1994. Relating wet and dry year ecophysiology to leaf structure in contrasting temperate tree species. Ecology 75:123-133.

Kubiske, M.E. and M.D. Abrams. 1994. Ecophysiology analysis of woody species in contrasting temperate communities during wet and dry years. Oecologia (Berlin) 98(3-4):303-312.

Abrams, M.D. 1992. Fire and the development of oak forests. BioScience 42:346-353.

Abrams, M.D. 1990. Adaptations and responses to drought in Quercus species of North America. Tree Physiology 7:227-238.

Abrams, M.D. and M.L. Scott. 1989. Disturbance-mediated accelerated succession in two Michigan forest types. For. Sci. 35:42-49