Current Research Projects

USDA McIntire Stennis: Coarse woody residue decomposition affected by southern pine beetle: fungal interactions influencing fire hazard in the NJ pine barrens.
With Ning Zhang (Plant Biology & Pathology, SEBS) and Matt Ayres (Dartmouth). Investigating the effects of wood invasion by southern pine bark beetle and the fungi introduced by them on the rate of decomposition of infested wood and changes in fungal succession on beetle damaged and non-beetle wood.

USDA McIntire Stennis: The role of Acidobacteria Communities in Carbon and Nitrogen Cycling Processes in New Jersey Pineland Soils.
With Max Haggblom (Biochemistry and Microbiology, SEBS) and Le Kerkoff (IMCS, SEBS). Understanding the edaphic factors affecting abundance of Acidobacter and it role in C cycling in pine barrens forests.

USDA McIntire Stennis: Impacts of Forest Thinning and Soil Disturbance on Sustainability in the NJ Pine Barrens.
This project, conducted at the New Jersey Conservation Foundation Parker Preserve,  involves a thinning and forest floor manipulation experiment following the ecological changes associated with replacement of ericaceous understory with a graminoid understory in the thinned forest. It is thought that this may have been the structure of these forests in pre-colonial times. The experimental manipulations  is investigating nutrient and carbon dynamics, tree performance and the success of generating a mixed species graminoid community from seed bank or by seeding with and without mycorrhizal inoculation.

Mesocosm studies of the effects of prescribed burning and forest floor disturbance.
This project takes some of the components of the Parker Preserve project (above) in combination with burning to follow the fate of soil nutrients with forest floor manipulations of burning, soil disturbance and understory vegetation removal. The experiment is set up under replicated individual trees within the field station property.

Influence of gypsy moth defoliation on carbon dynamics and nutrient dynamics in soil.
This project has arisen from three successive years of gypsy moth attack. In combination with the Forest Service, we have looked at the stand net carbon budget using eddy flux data. We are looking at the changes in chemistry of consumed leaves and the new flush of leaves post attack as well as decomposition of and mineralization from decomposing frass. 

Past Research Projects

NE SARE: An Integrated Approach to Developing Nutrient Management Schemes for Container-Grown Nursery Crops
This project is led By Dr. Gladis Zinati and is looking at the current nursery practices for cultivation of woody perennial ornamentals. We are testing the utility of adding mycorrhizal inocula to ectomycorrhizal, arbuscular mycorrhizal and ericoid mycorrhizal plants to enhance growth and reduce fertilizer and watering needs in an attempt to reduce nutrient run-off. The projects works with extension officers to provide education and training for the nursery industry in New Jersey and many of the experiments are conducted in the local nurseries.

USDA Forest Service: Atmospheric Deposition of Pollutants at the Rutgers University Pinelands Field Station (Silas Little Experimental Forest)
This project is evaluating the atmospheric deposition of nutrients into the forest.

NSF: REU Interdisciplinary Undergraduate Research Projects based on studies in the New Jersey Pinelands
This project is centered around the New Jersey pine barrens, but involves a number of faculty mentors in Biology, Chemistry and Physics from the Camden Campus. Students spend an orientation period at the field station, followed by ten weeks of focused research under the guidance of a faculty mentor. Each week seminars educate students on the process and ethics of research.

NSF: International Research Experience for Students: Impacts of Forest Floor Manipulations and the Problem of Post Harvest Residue Removal for Biofuels
This project is tied the forest floor manipulation experiment being carried out in the Parker Preserve (New Jersey Conservation Foundation) and to the research being carried out at the Finnish Forestry Research Institute (Metla) (Dr. Helja-Sisko Helmisaari). Each year four undergraduate students will participate in their own sub-section of these research efforts both in New Jersey and Finland. The New Jersey pine barrens project is a thinning and forest floor manipulation experiment following the ecological changes associated with replacement of ericaceous understory with a graminoid understory in the thinned forest. The Finnish component will study the implication of clear felling and complete removal of non-timber tree products and leaf litter for biofuels.

Biotic Indicators of Atmospheric Nitrogen Deposition
Principle Investigators – John Dighton, Dennis Gray, Amy Tuininga (Fordham University). This projects aims to assess the use of mycorrhizal fungi as indicators of N deposition. This is a joint project with Fordham University. Funded by the New Jersey Department of Environmental Protection.

Emergent properties of fungi exposed to long-term radiation: fungal ecophysiology
Principle Investigator: John Dighton. This is a joint project with the Institute of Microbiology and Virology, Kiev, Ukraine, the Institute for Nuclear Research, Kiev, Ukraine, and the A. N. Bach Institute of Biochemistry, Moscow, Russia. Funded by the National Science Foundation.

Biotic and Edaphic Controls of Ectomycorrhizal Community Structure and Function
Principal Investigators – John Dighton, John Lussenhop (University of Illinois at Chicago), Roger Koide (Pennsylvania State University) and Jim Baxter. This project is being run by Post-doctoral Associate, Lena Jonsson. This project examines the influence of leaf litter and fungal grazers on ectomycorrhizal community structure and host performance. We are currently manipulating oak, pine, huckleberry and mixed litter patches over minirhizotron tubes, which are placed horizontally in the organic horizon. Measurements include the dynamics of fine root growth and development of ectomycorrhizae under the influence of these litters. Manipulations are being carried out in the field (under mature trees), in mesocosms (under pine seedlings) and in microcosms. The influence of enhanced soil arthropod grazing pressure on the development of ectomycorrhizal communities under these litters is also being evaluated. This project was funded by USDA Soils program.

An Ecophysiological Approach to Understanding Mycorrhizal Community Functioning
Principal Investigators – John Dighton and Jim Baxter. This project is run by Jim Baxter, who is a Post-doctoral Associate at the Pinelands Field Station. The project examines the role of ectomycorrhizal diversity and composition in governing host plant performance and tests a physiological mechanism by which changes in diversity alter host growth and nutrient uptake. To accomplish this, we are measuring host responses to manipulations of ectomycorrhizal diversity and composition on experimental tree seedlings and characterizing the nutrient uptake capacities of single and mixed species assemblages of ectomycorrhizas on birch and pine. This project was funded by the National Science Foundation under Grant No. 9904007.

Soil Biodiversity and Risk Assessment
Project leaders – John Dighton, Bob Tate and Max Haggblom. Using molecular and physiological indicators of microbial community structure and activity the effects of different types of stress on pinelands soils are being investigated to assess the potential use of these indicators in ecotoxicology. Project funded by McIntire-Stennis (1997 – 2001).

Managed Fire Frequency and Forest Nutrient Sustainability in the New Jersey Pinelands
Project leader – John Dighton. Using a selection of upland pine dominated community sites of different control burn frequencies, the effect of fire on vegetation community structure, soil nutrients and microbial communities are being studied to evaluate the optimum burn regime for forest sustainability. Project funded by the Victoria Foundation (1997).

Ecosystem Mangement in Urban Settings
Project leader – Fred Grassle with Mike DeLuca, John Dighton, Sybil Seitzinger and John Wiggins. To link instructional programs with active research investigations, to train researchers, stewards and concerned citizens to manage natural areas in an informed manner and to develop a resource management model for areas threatened by population pressure. Project funded by Rutgers SROA grant (1997-1998).

Evaluation of the effects of distance of sewage discharge on stream and ground water chemistry
Directed by Dr M. J. Morgan, with the Pinelands Commission. Funded by the Noyes Foundation.

Sulfur transformations in freshwaters by bacterial process in relation to acid rain
Directed by Dr. M. J. Morgan. Ph.D. students: Susan Watts & Laura Lynch. Funded by NSF.

Forest floor patch dynamics and resource relations in litter: colonization by roots and nutrient cycling
Directed by Dr. John Dighton. Post-doctoral fellow Christine Conn. Funded by the Victoria Foundation.