Evaluation of CO2 rising effects on understory vegetation transpiration in Central Amazonia through an experiment-modeling integrated approach.

• Grant number: 21/14348-5
• Support Opportunities: Scholarships in Brazil - Master
• Effective date (Start): November 01, 2022
• Effective date (End): February 29, 2024
• Field of knowledge: Biological Sciences - Ecology - Ecosystems Ecology
• Principal Investigator: David Montenegro Lapola
• Grantee: Gabriel Banstarck Marandola
• Host Institution: Centro de Pesquisas Meteorológicas e Climáticas Aplicadas à Agricultura (CEPAGRI). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

Despite the constant progress in the area, the Amazon Forest vegetation responses to climate change are still not fully understood, especially the ones not related to the forest canopy. Concerning the changes in the water use of the forest related to rising carbon dioxide (CO2) concentrations, the different responses between the canopy and the understory strata of the western Amazonian are still uncertain. Thus, the goal of this project is to elucidate, in relation to the rising CO2 levels, the transpiration responses of central Amazon understory plants, which may result in consequences for the entire Amazon region, due to forest-atmosphere water flux disturbances. To accomplish this goal, we will evaluate individuals exposed to elevated carbon dioxide levels growing inside an open-top chamber experiment, which is installed in a terra firme forest located in the central Amazon. With the assessment of representative data of the understory humidity flux, such as stomatal conductance, carbon assimilation rate and transpiration estimates, it will be possible to compare estimates of this flux between the CO2 current atmospheric state and the condition simulated inside the chambers, which are maintained 250 ppm above the normal atmospheric levels. The comparison will enlighten the open topics cited about the understory stratum and make it possible to evaluate the performance of the dynamic vegetation model developed by the laboratory in which the research will be conducted regarding the understory transpiration simulation under different CO2 conditions.