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Taly Drezner

Taly Drezner

Associate Professor


PhD Geography, Arizona State University
MA Geography, Arizona State University
BA Geography, California State University, Fullerton

Research Keywords

Deserts & Arid Lands; Plant-Climate Interactions; Disturbance & Invasion; Biogeography.

Taly Drezner

Contact Information

4700 Keele Street
Toronto, ON M3J 1P3

416 736 2100

Research Interests

I am a physical geographer with a specialty in plants, plant-climate interactions, and facilitation (where a plant benefits from being located near another plant, such as under its canopy). My primary expertise is in desert ecosystems, though I also work in the Great Lakes region (among other places). I am currently working on several projects, including one with an endangered species of cactus at Point Pelee National Park (Ontario) to assist management with understanding its ecological limits, and aiding the Park’s conservation efforts. I study everything from its interactions with and dependence on other species, to microsite variations across its range. I also have active research in the Desert Southwest (Arizona, USA) looking at cactus demographics, facilitation, and responses to climate. Past work includes discovering that cacti may have greater establishment after volcanic eruptions, due to the temporary changes in climate that occur globally. For example, some Arizona cactus populations have many cacti that established around 1883 when Krakatau erupted in Indonesia.

In 2015, I was honoured to receive the Department's UNDERGRADUATE TEACHING AWARD, as selected by students. I teach a variety of classes, including -Physical Geography (1400) -Intro to Statistics (2420) -Disaster! The Earth's Extreme Natural Events (3700) -Desert Ecosystems (4410) -Seminar in Physical Geography (graduate class, 5600) and irregularly -Biogeography (3500) -Physical Geography of the City (3900).

Research Output

Drezner, T.D. 2020. The importance of microenvironment: Opuntia plant growth, form and the response to sunlight. Journal of Arid Environments 178:104144, July. DOI: 10.1016/j.jaridenv.2020.104144.

Drezner, ZVi and T.D. Drezner. 2020. Biologically Inspired Parent Selection in Genetic Algorithms. Annals of Operations Research 287(1743) , April. DOI: 10.1007/s10479-019-03343-7.

Drezner, T.D. 2019. Vegetation associations of the endangered Opuntia cespitosa (Prickly Pear, Cactaceae) and microsite variation in Point Pelee National Park, Ontario, Canada.  Physical Geography · November. DOI: 10.1080/02723646.2019.1684774.

Fall, P.L. and T.D. Drezner. 2019. Vascular plant species of the Kingdom of Tonga by vegetation type, species origin, growth form, and dispersal mechanism. Ecology 101(1), September. DOI: 10.1002/ecy.2902.

Sotomayor, D. and T.D. Drezner. 2019. Dominant plants alter the microclimate along a fog gradient in the Atacama Desert. Plant Ecology, March.  DOI: 10.1007/s11258-019-00924-1.

Drezner, ZVi and T.D. Drezner. 2019. The alpha male genetic algorithm. IMA Journal of Management Mathematics 30(1):37-50, January. DOI: 10.1093/imaman/dpy002.

Kent, A., T.D. Drezner, and R. Bello. 2018. Climate warming and the arrival of potentially invasive species into boreal forest and tundra in the Hudson Bay Lowlands, Canada. Polar Biology 41(10), June. DOI: 10.1007/s00300-018-2341-2.

Drezner, T.D. 2017. Variations In Saguaro Cactus ( Carnegiea gigantea ) Spine Length In Wet and Dry Portions of Their Range. Madroño 64(3):93-98, July. DOI: 10.3120/0024-9637-64.3.93.

Drezner, T.D. 2017. Shade, reproductive effort and growth of the endangered native cactus, Opuntia humifusa, in Point Pelee National Park, Canada. Journal of the Torrey Botanical Society. 144:179-190.

Drezner, T.D. 2017. North and south: morphological variability in the endangered Opuntia cespitosa in Canada and variation with environmental conditions. Castanea. 82: 8-23.

Drezner, T.D. 2016. Testing the validity of age-size reconstructions in cohort species, using Carnegiea gigantea. Journal of the Arizona-Nevada Academy of Science. 47: 23-27

Drezner, T.D., Drezner, Z., Balakrishnan, N. 2015. Estimating the transition of individuals between life stages. Environmetrics. 26: 526-533.

Dinh, T. Hewitt N., and Drezner, T.D. 2015. Fire history reconstruction in the black oak (Quercus velutina) savanna of High Park, Toronto. Natural Areas Journal. 35(3): 468-475.

Drezner, T.D. 2015. Regional environmental conditions affect microsite response in a keystone desert species. Journal of Arid Environments. 116: 89-95.

Gorelick, R., Drezner, T.D., Hancock, K. 2015. Freeze-tolerance of cacti (Cactaceae) in Ottawa, Ontario, Canada. Madroño 62: 33-45.

Drezner, T.D. 2014. The keystone saguaro (Carnegiea gigantea, Cactaceae): a review of its ecology, associations, reproduction, limits, and demographics. Braun-Blanquet invited review. Plant Ecology. 215: 581-595.

Danzer S. and Drezner, T.D. 2014. Relationships between epidermal browning, girdling, damage, and bird cavities in a military restricted database of 12,000+ plants of the keystone Carnegiea gigantea in the northern Sonoran Desert. Madroño. 61: 115-125.

Drezner, T.D. 2014. How long does the giant saguaro live? Life, death and reproduction in the desert. Journal of Arid Environments. 104: 34-37.

Recognition & Awards

  • Undergraduate Teaching Award, York LA&PS Department of Geography


Course CodeTitle
Winter 2021 EU/GEOG3700 3.0Disaster! Earth's Extreme Events  
Winter 2021 EU/GEOG2420 3.0Intro. Stats Analysis in Geography
Fall/Winter 2020 EU/GEOG1400 6.0Physical Geography