Research Overview

What limits the rate of photosynthetic carbon fixation in tropical trees?

Photosynthesis is a complex process for capturing carbon from the atmosphere. Multiple steps in this process can control the maximum rate of carbon capture. We use a combination of manipulative experiments and field observations to understand the rate-limiting steps for photosynthesis in different tropical tree species. We also study how environmental conditions and plant ontogeny might influence which step is rate-limiting.

How do species differ in their risk of overheating?

Species may differ in their heat tolerance but they also differ in the extent to which they experience heat, based on their architecture, morphology, and physiology. New technologies enable us to monitor temperatures of leaves in the canopy at a larger scale than traditional methods that involved attaching thermocouple wires to leaves. Monitoring canopy temperatures in diverse forest plots allows us to identify the species that experience the highest temperature extremes. We study these species in more detail to evaluate their physiological capacity to withstand high temperatures, and analyze the relative importance of architecture, morphology, and physiology as predictors of “overheating” of plants.

Does global warming threaten plant fertility in tropical forests?

Little is known about high-temperature thresholds for reproduction in wild plants, but studies on crops suggest that reproduction may fail at 30–39°C. If thresholds for reproduction are universal, tropical species are close to exceeding them, as temperatures there already routinely exceed 30°C. As temperatures continue to rise, seed production may drastically change in tropical forests, with consequences for species composition and community dynamics. Through experiments and field observations, we are studying tropical tree species’ vulnerability to heat-induced sterility, with the ultimate goal of understanding how rising temperatures may change forest community composition.

Education

M.Sc. Wageningen University, 2003

M.Res. University of York, 2004

Ph.D. University of Florida, 2013.

Selected Publications

Slot M, Krause GH, Krause B, Hernández GG, Winter K (2019) Photosynthetic heat tolerance of shade and sun leaves of three tropical tree species. Photosynthesis Research 141, 119–130.

Slot M, Winter K (2018) High tolerance of tropical sapling growth and gas exchange to moderate warming. Functional Ecology 32, 599–611.

Slot M, Winter K (2017) Photosynthetic acclimation to warming in tropical forest tree seedlings. Journal of Experimental Botany 68, 2275–2284.

Slot M, Winter K (2017) In situ temperature response of photosynthesis of 42 tree and liana species in the canopy of two Panamanian lowland tropical forests with contrasting rainfall regime. New Phytologist 214, 1103–1117.

Rey-Sánchez C, Slot M, Posada JM, Kitajima K (2016) Spatial and seasonal variation of leaf temperature within the canopy of a tropical forest. Climate Research 71, 75–89.

Slot M, Kitajima K (2015) General patterns of acclimation of leaf respiration to elevated temperatures across biomes and plant types. Oecologia 177, 885–900.

Slot M, Rey-Sánchez C, Gerber S, Lichstein JW, Winter K, Kitajima K (2014) Thermal acclimation of leaf respiration of tropical trees and lianas: response to experimental canopy warming, and consequences for tropical forest carbon balance. Global Change Biology 20, 2915–2926.

Slot M, Poorter L (2007) Diversity of tropical tree seedling responses to drought. Biotropica 39, 683–690.

 

Back to Top