Assembly Rules for Animal and Plant Communities in Changing Environments
Projects:
1. Effects of nutrient stress on a co-evolved food web. We are studying how atmospheric deposition of nitrogen is changing the food web dynamics, structure, and assembly of the detritus-based food web that inhabits the water-filled leaves of the northern pitcher plant, Sarracenia purpurea. The research is carried out in the bog at Harvard Forest's Tom Swamp, and in the Harvard Forest greenhouse.
2. Recovery and assembly trajectories of fen communities. In 2002, the largest fire in Oregon's history, the Sour Biscuit Fire, burned over 500,000 acres in the Siskiyou Mountains of Oregon and northern California. In this project, we are documenting the recovery of the vascular plant and ant communities, and the re-integration of ant-plant interactions in the Darlingtonia fens in these mountains.
3. Disintegration and reassembly of forest communities. We are witnessing the rapid loss of hemlock from forests of southern New England as it succumbs to the hemlock woolly adelgid. As part of a large-scale, multi-investigator project, We are developing statistical assembly rules for the tree, shrub, and herb assemblages that will replace hemlock in the next 20 years.
4. Response of ant communities to disturbance. We are examining how ant communities have responded to chronic nitrogen loading in hardwood and conifer stands, and how they will change following loss of hemlock resulting from infestation by the hemlock woolly adelgid. We are conducting an inventory of ant diversity in the long-term chronic N plots established by John Aber and Alison Magill (University of New Hampshire). We are also collecting base-line data on ant diversity in hemlock and hardwood stands prior to infestation by the adelgid and prior to experimental manipulations in which we either girdle or log hemlock stands.
5. Diversity of ant communities at the Harvard Forest. We are inventorying the diversity of ants at the Harvard Forest. This is one project addressing the long-term goal of biodiversity inventories of all taxa at the Harvard Forest.
Further Information:
http://harvardforest.fas.harvard.edu/personnel/web/aellison
http://www.uvm.edu/~biology/Faculty/Gotelli/Gotelli.html
Selected Publications
Dixon, P. M., A. M. Ellison, and N. J. Gotell. 2005. Improving the precision of estimates of the frequency of rare events. Ecology (in press).
Gotelli, N. J., and A. M. Ellison. 2005. Forecasting extinction risk with non-stationary matrix models. Ecological Applications (in press).
Ellison, A. M. and E. J. Farnsworth. 2005. The cost of carnivory for Darlingtonia californica (Sarraceniaceae): evidence from relationships among leaf traits. American Journal of Botany (in press).
Butler, J., D. Atwater*, and A. Ellison. 2005. Northern pitcher plants: an unappreciated sink for red-spotted newt larvae? Northeastern Naturalist (in press)
Ellison, A. M. 2004. Wetlands of Central America. Wetlands Ecology and management 12: 3-55.
Bazzaz, F. A. and S. Catovsky. 2005. Initial conditions and the structure of annual plant communities. Journal of Ecology (In Press).
Ellison, A. M., N. J. Gotelli, J. S. Brewer, L. Cochran-Stafira, J. Kneitel, T. E. Miller, A. S. Worley, and R. Zamora. 2003. The evolutionary ecology of carnivorous plants. Advances in Ecological Research 33: 1-74.
Buckley, H. L., T. E. Miller, A. M. Ellison, and N. J. Gotelli. 2003. Reverse latitudinal trends in species richness of pitcher-plant food webs. Ecology Letters 6: 825-829.
Bledzki, L. A. and A. M. Ellison. 2003. Diversity of rotifers from northeastern USA bogs with new species records for North America and New England. Hydrobiologica 497: 53-62.
Gotelli, N. J. and A. M. Ellison. 2002. Nitrogen deposition and extinction risk in the northern pitcher plant Sarracenia purpurea. Ecology 83: 2758-2765.
Gotelli, N. J. and A. M. Ellison. 2002. Assembly rules for New England ant assemblages. Oikos 99: 591-599.
Ellison, A. M., E. J. Farnsworth, and N. J. Gotelli. 2002. Ant diversity in pitcher-plant bogs of Massachusetts. Northeastern Naturalist 9: 267-284.
Catovsky, S. and F. A. Bazzaz. 2002. Feedbacks between canopy composition and seedling regeneration in mixed conifer broad-leaved forests. Oikos 98: 403-420.
Catovsky, S. and F. A. Bazzaz. 2000. The role of resource interactions and seedling regeneration in maintaining a positive feedback in hemlock stands. Journal of Ecology 88: 100-112.
Bazzaz, F. A. 1993. Scaling in biological systems: Population and community perspectives. Pp. 233-254 In .J. Ehleringer and C. B. Field (Eds.), Scaling Physiological Processes: Leaf to Globe. Academic Press, Inc., San Diego, CA.
Berliner, R. and J. G. Torrey. 1989. Studies on mycorrhizal associations in Harvard Forest, Massachusetts. Canadian Journal of Botany 67: 2245-2251.
Berliner, R. and J. G. Torrey. 1989. On tripartite Frankia - mycorrhizal associations in the Myricaceae. Canadian Journal of Botany 67: 1708-1712.