A5000786789- Plant Water Relations and Carbon Dynamics
- Plant responses to elevated CO2
- Ecology and Vegetation Dynamics Studies
- Tree-ring climate responses
- Forest ecology and management
- Plant and animal studies
- Peatlands and Wetlands Ecology
- Fire effects on ecosystems
- Species Distribution and Climate Change
- Atmospheric and Environmental Gas Dynamics
- Botany and Plant Ecology Studies
- Remote Sensing in Agriculture
- African Botany and Ecology Studies
- Atmospheric chemistry and aerosols
- Climate variability and models
- Bayesian Modeling and Causal Inference
- Plant Physiology and Cultivation Studies
- Metabolomics and Mass Spectrometry Studies
- Agroforestry and silvopastoral systems
- Soil Carbon and Nitrogen Dynamics
- Ecology and Conservation Studies
- Leaf Properties and Growth Measurement
- Soil and Water Nutrient Dynamics
- Phase Equilibria and Thermodynamics
University of Exeter
2022-2025
University of Gothenburg
2015-2024
Western University
2017-2024
Mount Allison University
2023-2024
University of Rwanda
2015-2021
Rising atmospheric carbon dioxide (CO2 ) concentrations may warm northern latitudes up to 8°C by the end of century. Boreal forests play a large role in global cycle, and responses trees climate change will thus impact trajectory future CO2 increases. We grew two North American boreal tree species at range conditions assess how growth fluxes were altered high warming. Black spruce (Picea mariana, an evergreen conifer) tamarack (Larix laricina, deciduous grown under ambient (407 ppm) or...
Abstract The temperature sensitivity of physiological processes and growth tropical trees remains a key uncertainty in predicting how forests will adjust to future climates. In particular, our knowledge regarding warming responses photosynthesis, its underlying biochemical mechanisms, is very limited. We grew seedlings two montane rainforest tree species, the early‐successional species Harungana montana late‐successional Syzygium guineense , at three different sites along an elevation...
Abstract Tropical forests take up more carbon (C) from the atmosphere per annum by photosynthesis than any other type of vegetation. Phosphorus (P) limitations to C uptake are paramount for tropical and subtropical around globe. Yet generality photosynthesis-P relationships underlying these in question, hence not represented well terrestrial biosphere models. Here we demonstrate dependence processes on both leaf N P concentrations. The regulation photosynthetic capacity was similar across...
Summary The sensitivity of photosynthetic metabolism to temperature has been identified as a key uncertainty for projecting the magnitude terrestrial feedback on future climate change. While responses capacities have comparatively well investigated in temperate species, tropical tree species remain unexplored. We compared seedlings native cold‐adapted montane rainforest with those exotic warm‐adapted plantation all growing an intermediate common garden Rwanda. Leaf gas exchange carbon...
Summary Current estimates of temperature effects on plants mostly rely air temperature, although it can significantly deviate from leaf ( T ). To address this, some studies have used canopy However, fails to capture the fine‐scale variation in among leaves and species diverse canopies. We infrared radiometers study how they (Δ Δ ) multispecies tropical tree plantations at three sites along an elevation gradient Rwanda. Our results showed high (up c . 50°C) (on average 8–10°C up 20°C)...
Leaf-level gas exchange data support the mechanistic understanding of plant fluxes carbon and water. These inform our ecosystem function, are an important constraint on parameterization terrestrial biosphere models, necessary to understand response plants global environmental change, integral efforts improve crop production. Collection these using analyzers can be both technically challenging time consuming, individual studies generally focus a small range species, restricted periods, or...
Warming shifts the thermal optimum of net photosynthesis (ToptA) to higher temperatures. However, our knowledge this shift is mainly derived from seedlings grown in greenhouses under ambient atmospheric carbon dioxide (CO2) conditions. It unclear whether ToptA field-grown trees will keep pace with temperatures predicted for 21st century elevated CO2 concentrations. Here, using a whole-ecosystem warming controlled experiment either or levels, we show that mature boreal conifers increased...
Leaf morphological traits vary along climate gradients, but it is currently unclear to what extent this results from acclimation rather than adaptation. Knowing so important for predicting the functioning of long-lived organisms, such as trees, in a rapidly changing climate. We investigated leaf warming responses 18 tropical tree species with early (ES) abd late (LS) successional strategies, planted at three sites an elevation gradient 2400 m a.s.l. (15.2 °C mean temperature) 1300 (20.6...
Abstract The productivity and climate feedbacks of tropical forests depend on tree physiological responses to warmer and, over large areas, seasonally drier conditions. However, knowledge regarding such is limited due data scarcity. We studied the impact growth temperature net photosynthesis (An), maximum rates Rubisco carboxylation at 25 °C (Vcmax25), stomatal conductance (gs) slope parameter conductance-photosynthesis model (g1), in 10 early successional (ES) 8 late-successional (LS)...
Summary Climate warming is causing compositional changes in Andean tropical montane forests (TMFs). These shifts are hypothesised to result from differential responses of cold‐ and warm‐affiliated species, with the former experiencing mortality latter migrating upslope. The thermal acclimation potential TMFs remains unknown. Along a 2000 m altitudinal gradient, we planted individuals species (under common soil irrigation), exposing them hot cold extremes their niches, respectively. We...
Summary Tropical climates are getting warmer, with pronounced dry periods in large areas. The productivity and climate feedbacks of future tropical forests depend on the ability trees to acclimate their physiological processes, such as leaf dark respiration ( R d ), these new conditions. However, knowledge this is currently limited due data scarcity. We studied impact growth temperature its dependency net photosynthesis A n nitrogen (N) phosphorus (P) contents, mass per unit area (LMA) 16...
Stomatal CO2 responsiveness and photosynthetic capacity vary greatly among plant species, but the factors controlling these physiological leaf traits are often poorly understood. To explore if linked to taxonomic group identity and/or other functional traits, we investigated short-term stomatal responses maximum rates of carboxylation (V cmax) electron transport (J max) in an evolutionary broad range tropical woody species. The study included 21 species representing four major seed taxa:...
Abstract Photosynthetic acclimation to both warming and elevated CO 2 of boreal trees remains a key uncertainty in modelling the response photosynthesis future climates. We investigated impact increased growth temperature on photosynthetic capacity ( V cmax J max ) mature two North American conifers, tamarack black spruce. show that at standard 25°C did not change with warming, while their thermal optima T opt g increased. Moreover, either 25°C, or decreased . The / ratio when assessed but...
Abstract Climate warming will alter photosynthesis and respiration not only via direct temperature effects on leaf biochemistry but also by increasing atmospheric dryness, thereby reducing stomatal conductance suppressing photosynthesis. Our knowledge how climate affects these processes is mainly derived from seedlings grown under highly controlled conditions. However, little known regarding responses of trees growing field settings. We exposed mature tamarack black spruce in a peatland...
Abstract Tropical canopies are complex, with multiple canopy layers and pronounced gap dynamics contributing to their high species diversity productivity. An important reason for this complexity is the large variation in shade tolerance among different tree species. At present, we lack a clear understanding of which plant traits control variation, e.g., regarding relative contributions whole-plant versus leaf or structural physiological traits. We investigated broad range six tropical...
Differences in photosynthetic capacity among tree species and functional types are currently assumed to be largely driven by variation leaf nutrient content, particularly nitrogen (N). However, recent studies indicate that N content is often a poor predictor of tropical trees. In this study, we explored the relative importance total area-based (Ntot) within-leaf allocation versus light-harvesting controlling (i.e. Vcmax, Jmax) mature trees 12 belonging either early (ES) or late successional...
Peatlands within the boreal-temperate ecotone contain majority of terrestrial carbon in this region, and there is concern over fate such stores face global environmental changes. The Spruce Peatland Response Under Changing Environments (SPRUCE) facility aims to advance understanding how peatlands may respond changes, using a combination whole ecosystem warming (WEW; +0, 2.25, 4.5, 6.75 9 °C) elevated CO2 (eCO2; +500 ppm) treatments an intact bog ecosystem. We examined photosynthetic...
Abstract Background and Aims Tropical forests exchange more carbon dioxide (CO2) with the atmosphere than any other terrestrial biome. Yet, uncertainty in projected balance over next century is roughly three-times greater for tropics ecosystems. Our limited knowledge of tropical plant physiological responses, including photosynthetic, to climate change a substantial source our ability forecast global sink. Methods We used meta-analytic approach, focusing on photosynthetic temperature address...