Use of LiDAR in the discrimination between mineral and organic soils under Atlantic Forest vegetation

• Grant number: 23/11171-2
• Support Opportunities: Scholarships in Brazil - Master
• Start date: December 01, 2023
• End date: February 28, 2025
• Field of knowledge: Agronomical Sciences - Agronomy - Soil Science
• Principal Investigator: Pablo Vidal Torrado
• Grantee: Ana Paula Dechen Rodrigues
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

Tropical wetlands are crucial for maintaining various ecosystem services, especially in mitigating greenhouse gas emissions, which have become a current point of interest due to their sensitivity and biodiversity. In the Atlantic Forest, peatlands are wetland ecosystems formed by Histosols in the swamp forest phytophysiognomy. The reducing conditions of these environments result in a geochemical dynamic that favors a significant carbon stock and greatly influences the dynamics and production of greenhouse gases such as CO2 and CH4. In the Swamp Forests of the Ribeira do Iguape Valley (São Paulo, Brazil), there are occurrences of both Histosols and hydromorphic mineral soils (Gleysols), making it challenging to discriminate between them, both due to difficulties in terrain accessibility and obtaining interpretative patterns from satellite images and aerial photographs. This research hypothesizes that although the swamp forest appears relatively uniform over both types of soils (Histosols and Gleysols), the vegetation should have distinct structures in each situation. By using geotools, such as active sensors like Light Detection and Ranging (LIDAR), it may be possible to obtain data about the forest structure, which could serve as indicators for the soil type in the environment. This hypothesis assumes that there is a relationship between soil attributes (pH, Eh, nutrient availability, water table fluctuation and organic matter content) and forest structure. To investigate this, metrics related to the height and structure of the forest canopy, as well as metrics related to the organic carbon content and soil geochemistry, will be used. It is expected that there will be differences between the forest structure and the soils, allowing the establishment of a protocol for identifying these areas and applying it to other areas of this ecosystem.