Colorado State Univ., Fort Collins, CO (United States)
Colorado State Univ., Fort Collins, CO (United States); Smithsonian Tropical Research Institute, Panama City (Panama); Univ. of California, Los Angeles, CA (United States)
Colorado State Univ., Fort Collins, CO (United States); Haverford College, PA (United States)
Baylor Univ., Waco, TX (United States)
Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
Univ. of California, Los Angeles, CA (United States)
Smithsonian Tropical Research Institute, Panama City (Panama)
Fine roots are key to ecosystem-scale nutrient, carbon (C), and water cycling, yet our understanding of fine root trait variation within and among tropical forests, one of Earth’s most C-rich ecosystems, is limited. We characterized root biomass, morphology, nutrient content, and arbuscular mycorrhizal fungal (AMF) colonization to 1.2 m depths across four distinct lowland Panamanian forests, and related root characteristics to soil C stocks. We hypothesized that: (H1) Fine root characteristics vary consistently with depth across seasonal tropical forests, with deeper roots exhibiting more exploratory traits, such as for deep water acquisition; (H2) fine root characteristics vary among tropical forests mainly in surface soils, where resource availability also varies. Here we found consistent variation with depth across the four forests, including decreased root biomass, root tissue density, and AMF, and increased specific root length. Among the forests, there was variation in some fine root characteristics, including greater surface root biomass and lower SRL in the wettest forest, and smaller fine root diameter in the driest forest. We also found that root characteristics were related to total soil C stocks, which were positively related to root biomass and negatively related to specific root length. These results indicate emergent properties of root variation with depth across tropical forests, and show site-scale variation in surface root characteristics. Future work could explore the flexibility in root characteristics under changing conditions such as drought.
@article{osti_2476139,
author = {Cordeiro, Amanda L. and Cusack, Daniela F. and Dietterich, Lee H. and Hockaday, William C. and McFarlane, Karis J. and Sivapalan, Vinothan and Hedgpeth, Alexandra and Neupane, Avishesh and Colburn, Lily and Konwent, Weronika and others},
title = {Root Characteristics Vary with Depth Across Four Lowland Seasonal Tropical Forests},
annote = {Fine roots are key to ecosystem-scale nutrient, carbon (C), and water cycling, yet our understanding of fine root trait variation within and among tropical forests, one of Earth’s most C-rich ecosystems, is limited. We characterized root biomass, morphology, nutrient content, and arbuscular mycorrhizal fungal (AMF) colonization to 1.2 m depths across four distinct lowland Panamanian forests, and related root characteristics to soil C stocks. We hypothesized that: (H1) Fine root characteristics vary consistently with depth across seasonal tropical forests, with deeper roots exhibiting more exploratory traits, such as for deep water acquisition; (H2) fine root characteristics vary among tropical forests mainly in surface soils, where resource availability also varies. Here we found consistent variation with depth across the four forests, including decreased root biomass, root tissue density, and AMF, and increased specific root length. Among the forests, there was variation in some fine root characteristics, including greater surface root biomass and lower SRL in the wettest forest, and smaller fine root diameter in the driest forest. We also found that root characteristics were related to total soil C stocks, which were positively related to root biomass and negatively related to specific root length. These results indicate emergent properties of root variation with depth across tropical forests, and show site-scale variation in surface root characteristics. Future work could explore the flexibility in root characteristics under changing conditions such as drought.},
doi = {10.1007/s10021-024-00941-w},
url = {https://www.osti.gov/biblio/2476139},
journal = {Ecosystems},
issn = {ISSN 1432-9840},
number = {8},
volume = {27},
place = {United States},
publisher = {Springer},
year = {2024},
month = {10}}