As a plant ecologist I am fascinated by the intriguing ways of how species interact with each other. Within that topic I address questions spanning community ecology, evolutionary ecology and ecophysiology. The list of keywords describing my past and present work is long: disturbance, breeding systems, diversity, invasion, seed ecology, root interactions, clonal plant biology, species interaction. So far I conducted field research in a wide range of systems ranging from Old World and New World deserts, through Mediterranean-type ecosystems to temperate forests. Significant parts of my research take place also in the greenhouse and the lab: sometimes nature is simply too complex to pursue specific questions.
Community ecology of plants - the theme of my research - is the examination of ecological and evolutionary processes and their outcome in plant populations and communities. These processes can be detected at a variety of ecological and temporal scales; accordingly, my research includes studies of individuals (ecophysiology), populations, communities and higher levels (flora).
I am pursuing two main goals: (1) to predict the ecological consequences and evolutionary trajectories of interactions between plants. Ecological interactions are understood to have the potential to lead to intricate co-evolution among interacting species. I am interested to find out whether coexisting species are coevolved and affect each other in non-random ways. The leading question is whether communities are much more than simple chance assemblies. Perturbed systems - systems that are altered from their pristine state - are ideal study objects to address such a question, since here coevolved interactions are likely disrupted. Good examples are plant communities that are invaded by alien organisms or systems otherwise heavily impacted by human activity. Needless to say, such systems are increasingly common throughout the East Coast Region. (2) to detect the mechanisms by which plants adapt to varying environments. Real environments are never constant and organisms are likely to encounter new abiotic factors and/or new neighbors. Evolutionary and ecological plant responses to stochastic environments often differ strongly from responses to predictable environmental change.
Representative publications (but see full list)
Holzapfel C., Parag, H.A., Shmida, (2009). Resilience of Mediterranean and desert vegetation after disturbance. Forstarchiv 90: 137-304.
Moloney K.A., Holzapfel C., Tielbörger K., Jeltsch, F, Schurr F. (2009) Rethinking the common garden in invasion research. Perspectives in Plant Ecology, Evolution and Systematics 11: 311-320.
Holzapfel C. (2008) Deserts. In S.E. Jørgensen & B.D. Fath (eds.), Vol.2 of Encyclopedia of Ecology, pp. 879-898. Oxford: Elsevier.
Sapir Y., Mazer S.J. & Holzapfel C. (2008) Sex Ratio. In S.E. Jørgensen & B.D. Fath (Eds.),. Vol. 4 of Encyclopedia of Ecology, pp. 3243-3248. Oxford: Elsevier.
Holzapfel C., Tielbörger K., Parag H.A., Kigel J., and Sternberg M. 2006. Annual plant-shrub interactions along an aridity gradient in Israel. Basic and Applied Ecology 7: 268-279.
Holzapfel C. & Alpert P. (2003): Root cooperation between plants of the same clone. Oecologia 134: 72-77.
Alpert P., Bone E. & Holzapfel C. (2000): Invasiveness and invasibility: the possible role of environmental stress in preventing biological invasions by plants. Perspectives in Plant Ecology, Evolution and Systematics 3: 52-66
Hamilton J.G., Holzapfel C. & Mahall B.E. (1999): Coexistence and interference between a native perennial grass and non-native annual grasses in California. Oecologia 121: 518- 526.
Holzapfel C. & Mahall B.E. (1999): Bidirectional facilitation and interference between shrubs and annuals in the Mojave Desert. Ecology 80: 1747-1761.
The greatest marvel of nature lies in its diversity. The first step to appreciate and to understand biological diversity is to get to know the parts of nature. Integral to my teaching approach is to submit a "feeling" about diversity in ecological systems. The types of diversity addressed do not stop at the level of species diversity, they include: diversity in strategies to cope with environment, diversity in ways to interact with neighbors within communities, and many more. In one phrase: diversity within diversity. Plant community ecology is a very dynamic research field and new themes are emerging frequently. Instruction to such a research area must involve overviews of past and current topics and introductions to budding new thoughts. I strive to "produce" fresh community ecologists who will contribute to such new thoughts and who will learn how to appreciate nature in its purest form: diversity.
As seen on the picture below (taken by Hadas July 4th, 2010) I do like marine ecosystems and, yes, I do enjoy long romantic strolls on the beach.
Oh, and I enjoy taking pictures of that very diversity (se above), a selection is below: