Biodiversity in Rainforest Canopies

Tropical tree crowns are structurally complex with steep gradients in microclimate, light availability, canopy humus (formed in situ), and branch size that create microhabitats from the inner to the outer crown. My research has focused on the role of this microhabitat heterogeneity in influencing patterns of epiphyte distributions and coexistence, properties of the canopy humus that develops from the decomposition of plant material, and how the lack of this heterogeneity in secondary forests may explain the lack of particular epiphyte species.

I am continuing this research in temperate rainforest canopies and found that structural heterogeneity also influences temperate epiphyte distributions.

Woods, C. L. , L. McKinley Nevins* and Emma Didier*. 2019. Structural heterogeneity of trees influences epiphyte distributions in a northern temperate rainforest. Journal of Vegetation Science. DOI:10.1111/jvs.12797

Woods, C. L. (2017) Primary ecological succession in vascular epiphytes: The species accumulation model. Biotropica 49:452-460.

Woods, C. L., C. L. Cardelús, and S. J. DeWalt. 2015. Microhabitat associations of vascular epiphytes in a wet tropical forest. Journal of Ecology 103:421–430.

Woods, C. L., and S. J. DeWalt. 2013. The conservation value of secondary forests for vascular epiphytes in central Panama. Biotropica 45:119–127.

Cardelús, C. L., M. C. Mack, C. L. Woods, J. DeMarco, and K. K. Treseder. 2009. The influence of tree species on canopy soil nutrient status in a tropical lowland wet forest in Costa Rica. Plant and Soil 318:47–61.

Conservation of Sacred Forests

Habitat fragmentation has resulted in many forest ecosystems being threatened. In the South Gondar region of Northern Ethiopia, more than 80% of the native forest has been converted to agriculture. The remaining intact forests are tiny fragments (~5 ha) that each surround an Orthodox Tewahido Church (see: Cardelus 2012). In collaboration with an interdisciplinary team of scholars including ecologists, physical and human geographers, and historians, we are exploring how strong common pool resource management allows particular communities to maintain or enhance the stewardship of church forests.

Woods, C. L. , A. Bitew Mekonnen, M. Baez-Schon*, R. Thomas**, P. Scull, B. Abraha Tsegay, and C. L. Cardelús. (2020). Tree community composition and dispersal syndrome vary with human disturbance in sacred church forests in Ethiopia. Forests 11:1082.


Cardelús, C. L., A. Bitew Mikonnen, K. H. Jensen, C. L. Woods, M. Baez, M. Montufar*, K. Bazany*, B. Tsegay Abraha, P. Scull, and W. Peck. (2020). Edge effects and human disturbance influence soil physical and chemical properties in Sacred Church Forests in Ethiopia. Plant and Soil. DOI: 10.1007/s11104-020-04595-0.  pdf

Cardelús, C. L., C. L. Woods, , A. Bitew Mikonnen, S. Dexter*, P. Scull, and B. Tsegay Abraha. (2019). Human disturbance impacts the integrity of sacred church forests, Ethiopia. PloS ONE 14(3):e0212430. pdf

Woods, C. L., C. L. Cardelús, P. S. Scull, A. Wassie, M. Baez*, and P. Klepeis. (2017) Stone walls and sacred forest conservation in Ethiopia. Biodiversity and Conservation, DOI: 10.1007/s10531-016-1239-y

Cardelús, C. L., P. Scull, A. Wassie Eshete, C.L. Woods, P. Klepeis E. Kent and I. Orlowska. (2017) Shadow conservation and the persistence of church forests in Northern Ethiopia. Biotropica 49:726-733. pdf.


Klepeis, P., I. Orlowska, E. Kent, C. L. Cardelús, P. Scull, A. Wassie Eshete, C.L. Woods. (2016) Ethiopian Church Forests: A Hybrid Model of Protection. Human Ecology, Human Ecology, DOI 10.1007/s10745-016-9868-z

Scull. P, Cardelús, C., Klepeis, P., Woods, C., Frankl, A., and J. Nyssen. (2016) The resilience of Ethiopian church forests: Interpreting aerial photographs, 1938-2015. Land Degradation and Development, DOI: 10.1002/ldr.2633

*denotes undergraduate student


One of the hypotheses to explain the coexistence of several plant species is niche differentiation. Species that coexist often vary in light, water and nutrient requirements, substrate type requirements, or germination requirements. We are examining whether nurse logs increase heterogeneity of regeneration sites within old-growth temperate rainforest, which would influence woody plant diversity and species distributions in these forests. We are also examining their role in density-dependence and whether the moss community on nurse logs influences woody species regeneration.

Woods, C. L., K. Maleta** and K. Ortmann**. (2021) Plant-plant interactions change during succession on nurse logs in a northern temperate rainforest. Ecology and Evolution.


Species Distributions in Temperate Rainforests