Grassland macroecology: An evolutionary perspective
Grasslands and savannas (“grassy systems”) account for ~40% of the global land surface and ~30% of terrestrial productivity. Three evolutionary lineages of grasses (Andropogoneae, Chloridoideae, and Pooideae) dominate grassy systems globally. Can these three lineages, or other grass evolutionary clades, help us better understand similarities in functional traits and ecological function in grasslands?
As part of a collaborative NSF-funded project we have collected a large suite of grass functional traits and hyperspectral reflectance spectra across an eco-climatic gradient at select NEON and LTER sites to answer questions about the evolution of trait coordination, how hyperspectral measurements can help us scale to landscape-level ecosystem function, and how grassy biomes will respond to climate change.
Funding: National Science Foundation Macrosystems Biology with PIs Christopher Still (Oregon State), Jesse Nippert (Kansas State), Brent Helliker (Penn), Dan Griffith (Oregon State), and Bill Riley (Lawrence Berkeley National Lab)
Grasslands and savannas (“grassy systems”) account for ~40% of the global land surface and ~30% of terrestrial productivity. Three evolutionary lineages of grasses (Andropogoneae, Chloridoideae, and Pooideae) dominate grassy systems globally. Can these three lineages, or other grass evolutionary clades, help us better understand similarities in functional traits and ecological function in grasslands?
As part of a collaborative NSF-funded project we have collected a large suite of grass functional traits and hyperspectral reflectance spectra across an eco-climatic gradient at select NEON and LTER sites to answer questions about the evolution of trait coordination, how hyperspectral measurements can help us scale to landscape-level ecosystem function, and how grassy biomes will respond to climate change.
Funding: National Science Foundation Macrosystems Biology with PIs Christopher Still (Oregon State), Jesse Nippert (Kansas State), Brent Helliker (Penn), Dan Griffith (Oregon State), and Bill Riley (Lawrence Berkeley National Lab)
Tropical forest phenology and productivity
Changes in the timing of repeated biological events – phenology – have provided some of the strongest evidence of climate change impacts on ecosystems. However, most of what we know about climate change impacts on plant phenology comes from temperate or high-latitude ecosystems. In the tropics there is a year-round growing season and a high diversity of species. Thus it is unclear how climatic fluctuations may affect species differently, and how variation among species is tied to changes in forest productivity.
A current NSF-funded project will integrate ground-based phenology and woody growth measurements with UAV hyperspectral, thermal, and lidar observations at two contrasting sites on the Island of Hawaii to understand species-specific phenology and associated productivity.
Funding: National Geographic Society; National Science Foundation Geography and Spatial Sciences (now HEGS) and DEB Ecosystem Science with co-PI Eben Broadbent (UF), co-PI Susan Cordell (USFS), and postdoc Shannon Bayliss (FSU)
Changes in the timing of repeated biological events – phenology – have provided some of the strongest evidence of climate change impacts on ecosystems. However, most of what we know about climate change impacts on plant phenology comes from temperate or high-latitude ecosystems. In the tropics there is a year-round growing season and a high diversity of species. Thus it is unclear how climatic fluctuations may affect species differently, and how variation among species is tied to changes in forest productivity.
A current NSF-funded project will integrate ground-based phenology and woody growth measurements with UAV hyperspectral, thermal, and lidar observations at two contrasting sites on the Island of Hawaii to understand species-specific phenology and associated productivity.
Funding: National Geographic Society; National Science Foundation Geography and Spatial Sciences (now HEGS) and DEB Ecosystem Science with co-PI Eben Broadbent (UF), co-PI Susan Cordell (USFS), and postdoc Shannon Bayliss (FSU)
Tropical Forest Temperature Thresholds for Primary Productivity
Canopy temperatures depart considerably from air temperatures, sometimes by as much as air temperatures are projected to increase by the end of this century, yet canopy temperatures are rarely considered in climate change analyses. We have been investigating spatial and temporal variability of forest canopy temperatures at Barro Colorado Island, Panama and Laupahoehoe, Hawaii. We've showed that temperatures are highly dynamic and rarely at their mean. GPP from eddy covariance began to decline at high temperatures above 32° C. Work in Hawaii is examining important species-specific differences in crown temperatures and disentangling the roles of crown structure and leaf traits on crown temperatures.
Funding: FSU Geography; FSU Provost's Postdoctoral Fellowship Program
Canopy temperatures depart considerably from air temperatures, sometimes by as much as air temperatures are projected to increase by the end of this century, yet canopy temperatures are rarely considered in climate change analyses. We have been investigating spatial and temporal variability of forest canopy temperatures at Barro Colorado Island, Panama and Laupahoehoe, Hawaii. We've showed that temperatures are highly dynamic and rarely at their mean. GPP from eddy covariance began to decline at high temperatures above 32° C. Work in Hawaii is examining important species-specific differences in crown temperatures and disentangling the roles of crown structure and leaf traits on crown temperatures.
Funding: FSU Geography; FSU Provost's Postdoctoral Fellowship Program