Emmanuelle Fréchette, PhD student

Manu

 

Climate warming will alter the photosynthetic capacity of boreal forests. In conifers, acclimation to temperature and light involves changes in photoprotective xanthophyll pigments. In the summer, these changes are closely correlated to PRI, an index that can be calculated from measurements of leaf spectral reflectance. PRI offers the exciting possibility of measuring the photosynthetic capacity of forests remotely. However, its use is still limited by the unclear relationship between xanthophyll dynamics and PRI in the spring and autumn. During these transitory periods, photoprotection is achieved through a variety of mechanisms that are not all reflected in the PRI signal. My aims are to (1) investigate the effects of warmer temperature in the spring and autumn on xanthophyll-cycle dynamics for more accurate assessment of future annual photosynthetic capacities of boreal forests, and (2) clarify the relationship between xanthophyll cycle dynamics, light-use efficiency of photosynthesis and PRI.

As a second-year undergraduate student at McGill University, I took an introductory course on forest science and immediately became captivated by everything related to the forest. A few years later I went on to get my Master’s degree in the lab of Frank Berninger at the Université du Québec à Montréal. During this time I traveled to the black spruce forests of Northern Québec, where I investigated the effects of soil insulation on the photosynthetic spring recovery of two boreal tree species.  My work led me to collaborate with Dr. Ensminger, who proved infectious with his enthusiasm for the processes and mechanisms behind photosynthesis. I then became a co-founding member of the Ensminger lab in September 2010. 

Email: emmanuelle.frechette@utoronto.ca

Lab: UTM Davis building 4033 ; tel 905-569-4235

Office: UTM Davis building 4078; tel 905-569-4988

See my ResearchGate profile here.

 

Publications:

1. Articles in refereed journals:

Fréchette, E., Chang, C.Y., Ensminger I. Photoperiod and temperature constraints on the relationship between the photochemical reflectance index (PRI) and the light-use efficiency of photosynthesis in Pinus strobus. Tree Physiology, in review. 

Fréchette, E., Wong, C.Y.S., Junker, L. V., Chang, C. Y., Ensminger, I. (2015) Zeaxanthin-independent energy quenching and alternative electron sinks cause a decoupling of the relation between the photochemical reflectance index (PRI) and photosynthesis in an evergreen conifer during spring. Journal of Experimental Botany. doi: 10.1093/jxb/erv427. link

Fréchette, E., Ensminger, I., Bergeron, Y., Gessler, A., Berninger, F. (2011) Will changes in root-zone temperature in boreal spring affect recovery of photosynthesis in Picea mariana and Populus tremuloides in a future climate? Tree Physiology 31, 1204-1216. link

2. Thesis:

Fréchette, E. (2009) Effets de l’enneigement et de l’entourbement sur la physiologie de l’épinette noire et du peuplier faux-tremble en forêt boréale québécoise. Master’s degree thesis, Université du Québec à Montréal, Montréal, Quebec. link

3. Other report:

Lecomte, N., Crocker, P., Cyr, D., Fréchette, E., Laib, B., Valeria, O. and Angers V.-A. (2010) Détermination des enjeux écologiques reliés à la mise en place d’un aménagement écosystémique et propres aux forêts de l’Abitibi-Témiscamingue. Rapport interne de la Conférence régionale des élus de l’Abitibi-Témiscamingue. link

4. Conference presentations:

Fréchette, E., Chang, C. and Ensminger, I. (2014) Facultative and constitutive changes in pigment composition affect the relationship of the photosynthetic light-use efficiency and the photochemical reflectance index of Eastern white pnine (Pinus strobus L.)Canadian Society of Plant Biologists Eastern regional meeting, November 29, Guelph, Ontario.

Fréchette, E., Chang, C. and Ensminger, I. (2013) The photochemical index (PRI) as an indicator of photochemical efficiency in Pinus strobus during the autumn. Canadian Society of Plant Biologists Eastern regional meeting, December 7, Mississauga, Ontario.

Chang, C., Fréchette, E. and Ensminger, I. (2013) Sensitivity of autumn cold-acclimation to elevated temperature in field-grown Pinus strobus seedlings. Canadian Society of Plant Biologists Eastern regional meeting, December 7, Mississauga, Ontario.

Fréchette, E., Chang, C. and Ensminger, I. (2013) The photochemical reflectance index as an indicator of photochemical efficiency of Eastern white pine (Pinus strobus) in a temperature manipulated field experiment​. Cell and Systems Biology Graduate Seminar Series, July 3, Toronto, Ontario.

Fréchette, E., Chang, C. and Ensminger, I. (2013) The photochemical reflectance index as an indicator of photochemical efficiency of Eastern white pine (Pinus strobus) in a temperature manipulated field experiment​. Canadian Society of Plant Biologists annual meeting, June 27, Quebec city, Québec.

Chang, C., Fréchette, E., Bin Yameen, T. and Ensminger, I. (2013) Temperature, photoperiod and CO2: Effects of changing climate on autumn photosynthesis and freezing tolerance in Pinus strobus. Canadian Society of Plant Biologists annual meeting, June 27, Québec city, Québec.

Fréchette, E., Chang, C. and Ensmnger, I. (2012) Temperature affects the spectral properties of Eastern white pine during the autumn downregulation of photosynthesis. Center for Global Change Science Graduate Symposium, November 30, Toronto, Ontario.  

Fréchette, E., Chang C. and Ensminger, I. (2012) Temperature affects the spectral properties of Eastern white pine during the autumn downregulation of photosynthesis. University of Toronto at Mississauga Bio-Geo Environmental Seminar Series, September 25, Mississauga, Ontario.

Fréchette, E., Chang, C., Ensminger, I. (2012) Temperature affects the spectral properties of Eastern white pine during the autumn downregulation of photosynthesis. Canadian Society of Plant Physiology annual meeting, June 25, Edmonton, Alberta.

Fréchette, E. and Ensminger, I. (2012) Linking xanthophyll cycle dynamics and leaf spectral properties of conifers to predict carbon uptake patterns of boreal forests in a warmer world. Monitoring the Breathing of the Earth Workshop, June 5, Edmonton, Alberta.

Fréchette, E., Berninger, F., Ensminger, I., Gessler A. and Bergeron, Y. (2010) Moss, snow and the effects of climate change on black spruce and trembling aspen. Center for Forest Research annual conference, March 14, Orford, Québec.

Fréchette, E., Berninger, F., Ensminger, I., Gessler A. and Bergeron, Y . (2009) Mousses et neige en forêt boréale: l’effet des changements climatiques sur l’épinette noire et le tremble. NSERC-UQAT-UQÀM Chair in sustainable forestry management annual conference, December 9, Rouyn-Noranda, Québec .

Fréchette, E., Berninger, F. and Bergeron, Y. (2009) The effects of moss and snow covers on the physiology of Picea mariana and Populus tremuloides in the boreal forest of Eastern Canada. Baden-Württemberg Forest Research Institute seminar, January 21, Freiburg, Germany.

5. Poster presentations:

Fréchette, E. Wong, C., Ensminger, I. (2015) Spying on the secret life of evergreen trees. Graduate Research Symposium. May 4, University of Toronto at Mississauga, Ontario.

Fréchette, E., Chang, C., Ensminger, I. (2013) Can we monitor the effects of climate change on forests using remote sensing? Research and Excellence Celebration for Graduate Students and Faculty Members. March 18, University of Toronto at Mississauga, Ontario.

Chang, C., Fréchette, E., Bin Yameen, T., Ensminger, I. (2013) How will forests respond to climate change? Determining the effects of elevated temperature and CO2 on autumn phenology of Pinus strobus. Research and Excellence Celebration for Graduate Students and Faculty Members. March 18, University of Toronto at Mississauga, Ontario.

Chang, C. Fréchette, E., Bin Yameen, T., Ensminger, I. (2012) Effects of simulated future climate on autumn freezing tolerance of Pinus strobus. Canadian Society of Plant Biologists Eastern regional meeting, December 1, Waterloo, Ontario.

Chang, C., Fréchette, E., Bin Yameen, T., Ensminger, I. (2012) Impact of simulated future climate on autumn photosynthesis and cold hardening in Pinus strobus. Canadian Society of Plant Biologists annual meeting, June 25, Edmonton, Alberta.

Fréchette, E. and Ensminger, I. (2011) Monitoring photosynthesis remotely: What is the relationship between xanthophyll cycle dynamics and PRI in the spring and autumn? Swiss Plant Science Web Summer School, Mürren, Switzerland.

 

Teaching assistantships:

2014      BIO312 Plant Physiology                                                                                                                                     BIO203 Introductory Plant Morphology and Physiology

2013      BIO312 Plant Physiology                                                                                                                                     BIO204 Introduction to Physiology

2012      BIO330 Plant Ecology                                                                                                                                           BIO204 Introduction to Physiology                                                                                     

2011      BIO153 Diversity of Organisms                                                                                                                           BIO204 Introduction to Physiology                                                                                     

2010      BIO205 Introduction to Ecology

 

Awards:

2013       Ontario Graduate Scholarship

2013       General Motors Women in Science and Mathematics Award

2012       Elizabeth Ann Wintercorbyn Award    

2011       Centre for Global Change Science Graduate Award

2008       Bourse Stages Internationaux FQRNT