Botany Department
University of Wisconsin-Madison
(608) 265-5473 fclandis@wisc.edu
Ph.D. Botany, December 2003, University of Wisconsin-Madison
M.A. Botany, December 1997, Humboldt State University, Arcata, CA
B.A. Environmental Science, May 1990, University of California at Berkeley
I finished my PhD under Dr. Givnish in December, and I am currently writing up my work for publication. My interests are plant ecology, arbuscular mycorrhizal ecology, and the evolution of mycorrhizae.
Recent research focused on the role played by arbuscular mycorrhizal fungi (AMF) in determining understory community composition in Wisconsin oak savannas, which are among the most species rich and endangered communities in Wisconsin. These studies focused on the interactions among the plant community, the fungal community, and light and soil texture and nutrient gradients that had been previously shown to affect plant community structure. I used a variety of methods, including field sampling in three savannas, a fungicide suppression study, and greenhouse studies. The field study showed that plant and AMF species richness and community composition were significantly correlated, and that both responded to the same soils gradient. In sandy, low nutrient savannas, there were few AMF and plant species per sample, whereas at the high clay, high nutrient end, there were far more AMF and plant species per sample. Interestingly, the number of plant species at each site was similar, over 100 species per savanna. The correlations between plant and fungi were seen only at a fine scale. The greenhouse experiments modelled the sandy savanna, using plants, fungi, and soil from the site. Here, I found that AMF had neutral to negative effects on the plant growth and competition. Interestingly, the results were consistent with both the field survey and with the fungicide study (the fungicide had no effect on community composition). Taken together, these studies suggest that oak savannas run the gamut in AMF-plant interactions, and that they are a good study system for this interaction.
My masters thesis was a baseline sampling of the chaparral on Santa Catalina Island, which is unusual in that (at the time of the study) it was heavily grazed, but rarely burned. The survey was conducted in 1995, at a time when large herbivores were being eliminated from the island. I surveyed 77 plots in chaparral patches across the island, taking a variety of plant and environmental measurements. Analysis showed that the chaparral could be classified into seven dominance types,with scrub oak (Quercus pacifica) dominating 52 plots. The history of grazing and lack of fire had resulted in a chaparral dominated by large obligate resprouters. Distribution of most species was patchy across the island, with most species being common in a few plots, and uncommon in many others. Reproduction was patchy as well, and seedlings where generally not found in plots with dying plants. When I first analyzed these data in 1996, they crashed the computer. Currently, I am reanalyzing the dataset using a much more powerful computer and software, examining questions about the how reproduction and mortality vary among species and across the island.
Other research interests include the evolution of different mycorrhizal states. The available evidence, both fossil and molecular, suggests that AMF coevolved with land plants, and that all other nutrient uptake mechanisms, from non-mycorrhizal roots to different mycorrhizal types to parasitism and carnivory (over a dozen mechanisms in all) evolved in plants with AMF ancestors, usually several times independently. I am interested in understanding the preadaptations from which these alternate mechanisms evolved, and in determining what environments favor the evolution of the alternates. Some mechanisms, such as carnivory, have been well studied. Others, such as ectomycorrhizae, are little studied from an evolutionary standpoint. For me, this is an "emerging area" of research (I am seeking funding), and I created a website in January 2002 (Mycorrhizae and plant phylogeny (link to website) as an overview of the subject, displaying a mapping of mycorrhizal states onto a phylogenetic tree of the plant kingdom. This idea was "in the air" in 2001. Mark Brundrett published a similar (albeit less detailed) diagram in his excellent Tansley Review article in New Phytologist (June 2002).
I am also involved in creating a California listing package for Astragalus brauntonii, a federally listed endangered plant that grows in Los Angeles and Orange Counties. This species is unusual for southern California in that it is a dedicated calciphile, apparently occuring only on one rock formation. A short-lived perennial, it is also a disturbance follower, and preservation of the species appears to rest on preservation of its seed bank.
Publications
Landis, F.C., A. Gargas, and T. J. Givnish. Accepted. The relationship between plant understory and arbuscular mycorrhizal fungal communities in American midwestern oak savannas. New Phytologist.
Landis, F.C., A. Gargas, and T. J. Givnish. Submitted. The influence of arbuscular mycorrhizae and light on Midwestern sand savanna understories I. plant community composition. Mycorrhiza.
Landis, F.C., A. Gargas, and T. J. Givnish. Submitted The influence of arbuscular mycorrhizae and light on Midwestern sand savanna understories II. plant competition. Mycorrhiza.
Landis, F.C., J. O. Sawyer. In Prep. Composition and structure of chaparral on Santa Catalina Island, California. Madrono.
Landis, F. C. 2000. Unburned and grazed chaparral; a case study. Pp. 57-71 in J. E. Keeley, M. Baer-Keeley, and C.J. Fotheringham (eds). Second Interface Between Ecology and Land Development in California. Sacramento, CA. USGS Open-File Report 00-62.
Landis, F.C. 1994. Surveying Santa Catalina Island plant communities. Fremontia. 22(2) pp. 24-27.
Contact me at fclandis@wisc.edu for more information about any of these publications.
