The Role of the Ecosystem Engineer, the Leaf‐Cutter Ant Atta cephalotes , on Soil CO 2 Dynamics in a Wet Tropical Rainforest
Year: 2018
Type: article
Abstract: Leaf‐cutter ants are dominant herbivores that disturb the soil and create biogeochemical hot spots. We studied how leaf‐cutter ant Atta cephalotes impacts soil CO 2 dynamics in a wet Neotropical forest. We measured soil CO 2 concentration monthly over 2.5 years at multiple depths in nonnest and nest soils (some of which were abandoned during the study) and assessed CO 2 production. We also measured nest and nonnest soil efflux, nest vent efflux, and vent concentration. Nest soils exhibited lower CO 2 accumulation than nonnest soils for the same precipitation amounts. During wet periods, soil CO 2 concentrations increased across all depths, but were significantly less in nest than in nonnest soils. Differences were nonsignificant during drier periods. Surface efflux was equal across nest and nonnest plots (5 μmol CO 2 m −2 s −1 ), while vent efflux was substantially (10 3 to 10 5 times) greater, a finding attributed to free convection and sporadic forced convection. Vent CO 2 concentrations were less than in soil, suggesting CO 2 efflux from the soil matrix into the nest. Legacy effects in abandoned nests were still observable after more than two years. These findings indicate that leaf‐cutter ant nests provide alternative transport pathways to soil CO 2 that increase total emissions and decrease soil CO 2 concentrations, and have a lasting impact. Estimated total nest‐soil CO 2 emissions were 15 to 60% more than in nonnest soils, contributing 0.2 to 0.7% to ecosystem‐scale soil emissions. The observed CO 2 dynamics illuminate the significant carbon footprint of ecosystem engineer Atta cephalotes and have biogeochemical implications for rainforest ecosystems.
DOI: 10.1029/2018jg004723
Institutions: University of California, Merced, Organization for Tropical Studies, Florida International University, University of California, Riverside, Center for Conservation Biology, College of Saint Benedict and Saint John's University, Universidad de Costa Rica, University of Puerto Rico-Mayaguez, University of Wyoming, University of Puerto Rico at Río Piedras, University of California, Los Angeles, University of Auckland
Language: English
Subfield: Soil Science
Domain: Life Sciences
SDGs: Climate action, Life on land
Open Access status: bronze
Awards: An OTS LSAMP Program for Native American, Pacific Islander, Hispanic American, and African American Students at two Research Stations in Costa Rica, Collaborative Research: Quantifying the footprint of a dominant organism: Biogeochemical impacts of leaf cutter ants in a lowland tropical forest ecosystem, Collaborative Proposal - Quantifying the footprint of a dominant organism: Biogeochemical impacts of leaf cutter ants in a lowland tropical forest ecosystem, G4000462912, G4328568919, Collaborative Research: Quantifying the footprint of a dominant organism: Biogeochemical impacts of leaf cutter ants in a lowland tropical forest ecosystem, Collaborative Proposal - Quantifying the footprint of a dominant organism: Biogeochemical impacts of leaf cutter ants in a lowland tropical forest ecosystem, REU Site: Research Experiences for Undergraduates in Tropical Biology at the La Selva Biological Station, Costa Rica
OpenAlex ID: W2901086596