Use of thermal sensors for monitoring natural attenuation of tropical soils contaminated by hydrocarbons

• Grant number: 24/11080-0
• Support Opportunities: Scholarships in Brazil - Master
• Start date: November 01, 2024
• End date: September 30, 2025
• Field of knowledge: Engineering - Sanitary Engineering - Environmental Sanitation
• Principal Investigator: Cristina Rossi Nakayama
• Grantee: Maria Eduarda da Costa Silva
• Host Institution: Instituto de Ciências Ambientais, Químicas e Farmacêuticas (ICAQF). Universidade Federal de São Paulo (UNIFESP). Campus Diadema. Diadema , SP, Brazil

Abstract

This project aims to continue the master's research initiated under project No. 17/50343-2, "Institutional Development Plan in Digital Transformation: Advanced Manufacturing and Smart Sustainable Cities (PDIp)", funded from May 1, 2018, to April 30, 2024, focusing on characterizing biological processes of natural attenuation in soils contaminated with creosote. The research utilizes column models coupled with temperature sensors to simulate Natural Source Zone Depletion (NSZD) and investigate the feasibility of temperature monitoring for detecting biodegradation in these areas. In the completed phase of the study, a column model coupled with DS18B20 sensors in modules developed by the Instituto de Pesquisas Tecnológicas (IPT) was validated and operated using soil from a creosote-contaminated area managed by IPT in São Paulo city. This phase evaluated the contamination's influence on soil temperature and response to new contamination introduced into the column. This project proposes to characterize the soil microbiota collected from the operated models and repeat the experiment using naphthalene as a model PAH to estimate biodegradation rates associated with soil temperature variations. 16S rRNA sequencing will be used to describe taxonomic diversity, while qPCR techniques will determine microbial population densities and functional genes of interest. Quantification of PAHs/naphthalene in soil samples will be performed using gas chromatography coupled with mass spectrometry. Bioinformatics and statistical analyses of sequencing data will describe changes in diversity associated with soil contamination. Microbial density data and naphthalene decay rates will estimate biodegradation rates and correlate these with temperature variations recorded through statistical analyses. The outcomes aim to contribute to understanding natural attenuation processes of PAHs in tropical soils and to foster the development of remediation strategies for contaminated areas based on nature-based solutions.