Above- and belowground biomass and soil carbon stocks and their relationships with land use in Ilha das Cinzas at the Amazon River Estuary, Brazil

• Grant number: 24/07604-3
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: February 01, 2025
• End date: January 31, 2027
• Field of knowledge: Agronomical Sciences - Forestry Resources and Forestry Engineering - Nature Conservation
• Principal Investigator: Ciro Abbud Righi
• Grantee: Tiruneh Gizachew Ayalew
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated research grant: 22/10456-0 - Generation and integration of biomass and photovoltaic energy to strengthen production chains of isolated communities in the Amazon River Estuary, AP.R

Abstract

The Amazon rainforest is home to one of the greatest biodiversity on the planet. Furthermore, it plays a fundamental role in the carbon cycle, acting as a huge reservoir which, associated with its extension, makes this forest play an important role in the world. The people who live there make use of its resources for their livelihood, altering the landscape. The Amazon River estuary with its islands and characteristic vegetation are still little studied and characterized despite its importance. Therefore, it is essential to determine land use systems, carbon stocks and soil fertility in this Amazon region. This study aims to establish a timeline of land use changes and their effects on Amazonia's forest biomass and soil carbon stocks. The main goal is to analyze the above-ground biomass, vegetation carbon stocks, and soil carbon stocks in soil profiles related to land cover on the islands situated in the Amazon River estuary. By using land use categories and determining flood gradients along the Amazon river banks, we will employ a chronosequence substitution method to assess the differences in aboveground biomass (AGB) and belowground biomass (BGB) and carbon (C) stocks at different tree growth stages, coverage areas, and flooding levels. Species-specific allometric equations and biomass-to-carbon conversion factors will be used to estimate tree AGB and BGB as well as corresponding C stock in the study area. Additionally, satellite data will be utilized to estimate forest sequestered C and forest AGB under the ArcGIS platform. ArcGIS will help create yield maps for biomass and carbon stock based on the best-fit regression models. A flora diversity analysis using the Shannon-Weiner diversity index will be conducted, and soil samples from circular plots will be analyzed for soil pH, organic C content, and macro-elements. The study will also assess the significance of mean differences in AGB, BGB, pH, C, soil macronutrients, moisture, and bulk density content as dependent variables.