Fulbright Fellow, Fulbright Scholar Program, 1994–97
Adjunct Professor, Biological Sciences, Northwestern University, 2003 – present
2003 – present Member, Soil Science Society of America
2000 – present Member, Mycological Society of America
1996 – present Member, Ecological Society of America
1995 – present Member, Microscopy Society of America
1994 – present Member, Australian and American Fulbright Alumni
1994 – present Member, Australia Society for Microscopy
- Fungal diversity, functioning, and ecology with an emphasis on mycorrhizal fungi
- Consequences of alterations in climate, land-use, and species invasion cycles on plant-soil interactions
- Fungal contributions to soil carbon sequestration and stability
- Resilience, complex systems, and network theory
My research focuses on the ecological links between the above- and below-ground biota, and in particular how mycorrhizal fungi are fundamental to the wellbeing of all aboveground communities and ecosystems. Mycorrhizal fungi form relationships with plant roots, and grow fine root-like hyphae into the soil, where they acquire and transfer resources (water, phosphorus, nitrogen) to the plant in return for sugars to sustain growth. Their biomass can outweigh that of any other component in the soil biota, and their roles range from the control of nutrient cycling and the immobilization of greenhouse gases in their tissues (e.g., CO2) through to enhancing plant productivity and protection from diseases.
Two recurring themes in my research are the mechanistic understanding of how these plant-fungal interactions affect community and ecosystem processes, and the consequences of alterations in climate, land-use, and species invasions on this relationship.
My current research projects can be broadly grouped into four areas:
- Soil carbon sequestration: identifying and quantifying the pathways of carbon flow through rhizosphere fungal communities;
- Understanding legacy effects in soils: plant community composition and management effects on microbial communities and biogeochemistry;
- Mycorrhizal diversity and functioning: identifying the pathways by which mycorrhizal fungi are involved in the uptake and (re-) distribution of water; and
- Ecological controls of mycorrhizal fungal diversity and community structure: the extent to which mycorrhizal fungi demonstrate resilience and adaptation to changes in the global environment.
My approach to all research is pluralistic. I use both laboratory and field experiments to test ecological theory, and I use molecular genetic techniques, stable isotopes, microscopy, standard in vitro culture techniques, and quantitative techniques, as well as well as algorithmic and statistic analyses. The questions I ask range from local or individual through to ecosystem-level responses in tallgrass prairies, oak-maple woodlands, and dry seasonal tropical forests.
My research program actively involves high-school students (summer only), undergraduates (summer only), and graduate students (year-round).
Querejeta, J.I., Egerton-Waburton, L.M., Prieto, I., Vargas, R., Allen, M.F. (2012). Changes in soil hyphal abundance and viability can alter the patterns of hydraulic redistribution by plant roots. Plant and Soil 355: 63-73.
Querejeta, Egerton-Warburton, L.M., and Allen, M.F. (2009). Differential access to groundwater modulates the mycorrhizal responsiveness of oaks to inter-annual rainfall variability in a California woodland. Ecology 90: 649-662.
Egerton-Warburton, L.M., Querejeta, J.I., and Allen, M.F. (2008). Efflux of hydraulically-lifted water by mycorrhizal hyphae during imposed drought. Plant Signaling and Behavior 3: 68-71.
Egerton-Warburton, L.M., Johnson, N.C., and Allen, E.B. (2007). Mycorrhizal community dynamics following nitrogen fertilization: a cross-site test in five grasslands. Ecological Monographs 77: 527-544.
Plamboek, A.H., Dawson, T.E., Egerton-Warburton, L.M., North, M., Bruns, T.D., and Querejeta, J.I. (2007). Water transfer via ectomycorrhizal fungal hyphae to conifer seedlings. Mycorrhiza 17: 439-447.
Querejeta, J.I., Egerton-Warburton, L.M., and Allen, M.F. (2003). Direct nocturnal water transfer from oaks to their mycorrhizal symbionts during severe soil drying. Oecologia 134: 55-64.
Egerton-Warburton, L.M., Graham, R.C., Allen, E.B, and Allen, M.F. (2001). Reconstruction of the historical changes in mycorrhizal fungal communities under anthropogenic nitrogen deposition. Proceedings of the Royal Society of London, Series B 268: 2479-2484.
Egerton-Warburton, L.M., and Allen, E.B. (2000). Shifts in the diversity of arbuscular mycorrhizal fungi along an anthropogenic nitrogen deposition gradient. Ecological Applications 10: 484- 496.
International Culture Collection of (Vesicular) Arbuscular Mycorrhizal Fungi (INVAM)
INVAM is a living culture collection, where the primary goal is to acquire, propagate, characterize, and maintain germplasm of AMF in living cultures for preservation and distribution to any person or institution. The collection is curated and maintained by Dr. Joe Morton at WVU. The site contains germplasm information and accessions, basic tools in fungal biology, taxonomy, and ecology of AMF. Sister site: La Banque Européenne des Glomales (BEG), http://www.kent.ac.uk/bio/beg/
DEEMY is an information system for the morphological characterization of ectomycorrhizal fungi.
UNITE is molecular database for the identification of fungi, primarily fungal rDNA ITS sequences, and designed to facilitate identification of environmental samples of fungal DNA.
The Santa Fe Institute
The Santa Fe Institute is a private, nonprofit research institute that has defined complex systems research and promoted the understanding of complex adaptive systems critical to addressing key environmental, technological, and biological challenges.