A key aspect of our USDA fellows' training experience is their joint participation in a model forest management and restoration project in a local forest ecosystem. The trainees develop research projects within the context of this larger ongoing project, giving them 1st-hand experience with collaborative research in science-based forest restoration ecology. Participation in this project trains students in the use of manipulative experimentation to test restoration practices, as well as thorough post-treatment monitoring. Two major challenges for effective ecological restoration as well as the science of applied ecology are 1) the practice of ecological restoration often proceeds in a non-scientific manner (e.g., lack of replication or thorough monitoring; Zedler 1996, Cabin 2007), and 2) most ecological research that claims to be relevant to conservation and restoration, though perhaps scientifically sound, rarely has practical benefits for conservation or restoration (Ehrenfeld 2000; Cabin 2007).
Recent work at the University of Mississippi has shown that fire historically played an important role in structuring species-rich plant communities in the vicinity of small creeks and springs within an upland landscape of pine- and oak-dominated woodlands in north Mississippi (Brewer 2001; Surrette, Brewer, and Aquilani 2008; Surrette and Brewer 2008). Other recent work at the University of Mississippi has shown that transitional zones between terrestrial and aquatic ecosystems in north Mississippi are important in regulating nutrient and sediment run-off from terrestrial to aquatic ecosystems (e.g., Rajkarnikar 2005). Ecological restoration of closed-canopy forests to open, fire-maintained woodlands provides an opportunity to examine the impact of restoration treatments such as selective thinning and prescribed burning on terrestrial species composition and ecosystem processes, the potential side effects of these treatments on nutrient and sediment run-off from upland areas into creeks, and consequent impacts on aquatic food webs.
The PIs and USDA fellows, in cooperation with the managers of a local forest reserve (Strawberry Plains Audubon Center), maintain long-term restoration treatments (including selective thinning of off-site alluvial tree species and invasive species, and prescribed burning) in selected mature oak and pine-oak forests, paired with untreated controls. As a team, the project directors and USDA fellows monitor ecosystem responses to these treatments, including plant, microbial, and animal responses to the treatments.
The overall objective of the research is to determine if ecological restoration can restore functional responses and population viability of fire-dependent flora, microorganisms, and fauna without jeopardizing the viability of any resident populations of species or eliciting sustained losses of nutrients or sediment from uplands into adjacent creeks.
- Rajkarnikar, B. 2005. The effect of timber harvesting on soil biogeochemical and physical properties: resilience studies on disturbed forests and their associated wetlands. Master's Thesis, University of Mississippi, Department of Biology.
- Brewer, J. S. 2001. Current and presettlement tree species composition of some upland forests in northern Mississippi. Journal of the Torrey Botanical Society 128: 332-349.
- Cabin, R. J. 2007. Science-driven restoration: a square grid on a round earth? Restoration Ecology 15:1-7.
- Ehrenfeld, D. 2000. War and peace and conservation biology. Conservation Biology 14:105-112.
- Surrette. S. B. and J. S. Brewer. 2008. Inferring relationships between native plant diversity and Japanese honeysuckle in upland forests in north Mississippi. Applied Vegetation Science 11:205-214.
- Surrette, S. B., S. M. Aquilani and J. S. Brewer. 2008. Current and historical composition and size structure of upland forests across a soil fertility gradient in north Mississippi. Southeastern Naturalist 7:27-48.