Relationship between tropical leaf phenology and ecosystem productivity using phenocameras

Author(s)

Alberton, Bruna ; Martin, Thomas C. M. ; Da Rocha, Humberto R. ; Richardson, Andrew D. ; Moura, Magna S. B. ; Torres, Ricardo S. ; Morellato, Leonor Patricia Cerdeira

• Document type: Journal article
• Source: FRONTIERS IN ENVIRONMENTAL SCIENCE; v. 11, p. 14-pg., 2023-09-14.

Abstract

Introduction: The interplay of water and light, regarded as the main driver of tropical plant dynamics, determines leaf phenology and ecosystem productivity. Leaf phenology has been discussed as a key variable to explain photosynthetic seasonality in evergreen tropical forests, but the question is still open for seasonally tropical ecosystems. In the search for implementing long-term phenology monitoring in the tropics, phenocameras have proven to be an accurate method to estimate vegetative phenology in tropical communities. Here, we investigated the temporal patterns of leaf phenology and their relation to gross primary productivity (GPP) in a comparative study across three contrasting tropical biomes: dry forest (caatinga), woodland savanna (cerrado), and rainforest (Atlantic Forest).Methods: We monitored leaf phenology (phenocameras) and estimated gross primary productivity (eddy-covariance) continuously over time at three study sites. We investigated the main drivers controlling leaf phenology and tested the performance of abiotic (climate) and biotic (phenology) factors to explain gross primary productivity across sites.Results: We found that camera-derived indices presented the best relationships with gross primary productivity across all sites. Gross primary productivity seasonality was controlled by a gradient of water vs. light, where caatinga dry forest was water-limited, cerrado vegetation responded to water seasonality and light, and rainforest was mainly controlled by light availability. Vegetation phenology was tightly associated with productivity in the driest ecosystem (caatinga), where productivity was limited to the wet season, and the camera-derived index (Gcc) was the best proxy for gross primary productivity.Discussion: Leaf phenology increased their relative importance over gross primary productivity seasonality at less seasonal sites (cerrado and rainforest), where multiple leafing strategies influenced carbon exchanges. Our multi-site comparison, along with fine-scale temporal observations of leaf phenology and gross primary productivity patterns, uncovered the relationship between leafing and productivity across tropical ecosystems under distinct water constraints. (AU)

• FAPESP's process: 14/00215-0 - Remote phenology and leaf exchange patterns towards a sazonality gradient
• Grantee: Bruna de Costa Alberton
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 13/50155-0 - Combining new technologies to monitor phenology from leaves to ecosystems
• Grantee: Leonor Patricia Cerdeira Morellato
• Support Opportunities: Research Program on Global Climate Change - University-Industry Cooperative Research (PITE)
• FAPESP's process: 10/52113-5 - e-phenology: the application of new technologies to monitor plant phenology and track climate changes in the tropics
• Grantee: Leonor Patricia Cerdeira Morellato
• Support Opportunities: Research Program on Global Climate Change - Regular Grants
• FAPESP's process: 09/54208-6 - Multi-User Centralized Laboratory at the São Paulo State University Center for Biodiversity Studies
• Grantee: Célio Fernando Baptista Haddad
• Support Opportunities: Multi-user Equipment Program
• FAPESP's process: 19/23853-5 - Regional risks and opportunities on land use change and climate change with thermal-water ecosystem services: investigation for basins in Caatinga and Atlantic Forest
• Grantee: Humberto Ribeiro da Rocha
• Support Opportunities: Regular Research Grants
• FAPESP's process: 21/11762-5 - Centre for Water and Food Security in Critical Zones
• Grantee: Humberto Ribeiro da Rocha
• Support Opportunities: Research Grants - Science Centers for Development
• FAPESP's process: 15/50488-5 - Nordeste: new science for a neglected biome
• Grantee: Jonathan James Lloyd
• Support Opportunities: Research Projects - SPEC Program
• FAPESP's process: 16/01413-5 - Using leaf phenology patterns to investigate net ecosystem exchange controls in tropical vegetations
• Grantee: Bruna de Costa Alberton
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• FAPESP's process: 19/11835-2 - Phenology of deciduous dry forests: a comparison at multiple spatial scales using phenocams and drones
• Grantee: Leonor Patricia Cerdeira Morellato
• Support Opportunities: Regular Research Grants