ABATI - Airbone pollution by vegetation and tree samples bio-sensor In two constricted OHMi with different human activities

Résumé fourni par la source

The numerous deleterious health impacts of poor air quality are now recognized. Assessing the concentrations and dispersions of ambient air particles appears necessary in the monitoring of contaminant emissions related to anthropogenic activities. The use of geochemical and magnetic measurements on vegetation, which acts as a natural sensor, offers an alternative to dedicated air quality monitoring stations. Magnetic and geochemical methods allow the processing of large numbers of samples, thus facilitating spatialized monitoring. The Estarreja (Portugal) and Téssékéré (Sénégal) sites provide study sites for testing different types of vegetation and anthropogenic (industry, traffic) and natural (wind-borne desert lithic particles) sources. The project proposes to measure magnetic properties (magnetic susceptibility and magnetization in strong fields) as well as to acquire geochemical data (metallic traces) on 1- bark and leaves geolocated around the sites of interest and 2- to carry out exposure tests on bark in order to produce passive biosensors. These data will make it possible to identify the fingerprints of the sources. Preliminary results were obtained on 40 bark samples from Estarreja (mainly Eucaplyptus) and 28 from the Téssékéré region (various species including Balanites aegyptiaca and Acacia). The magnetic susceptibility is indicative of the content of ferromagnetic particles (magnetite-like) trapped in bark. In Estarreja, magnetic susceptibility values vary between -6.4 10-9 and 1.9 10-8 m3.kg-1. The highest values are measured in the bark from trees near a highway. Estimating the capture of ambient air particles by plants will make it possible to -1- propose easy-to-implement biomonitoring methods, - 2 - propose passive biosensors for locations without vegetation and to set up, in the long term, participatory processes involving local stakeholders, and - 3 - estimate the role of vegetation in the retention of airborne particles in different environments.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.