Forested Infiltration Area System
Indice degli argomenti
-
The Forested Infiltration Area (FIA) system aims at mitigating the groundwater nitrate contamination for the shallow sandy aquifer in the Nitrate Vulnerable Zone (NVZ) of Arborea (Italy).
FIA has been implemented by the Desertification Research Center of the University of Sassari in the framework of the international project "Non-conventionAl WAter Reuse in Agriculture in MEditerranean Countries (MENAWARA)".
FIA is a Managed Aquifer Recharger (MAR) technique consisting in the distribution of surface water on areas specially equipped with a network of drainage trenches and forested with trees and/or shrub species. The forest area maximaze the infiltration rate whereas the "active layer" generated has an effective action to promote nitrate attenuation.
The FIA system implemented in the intervention area of Arborea (Sardinia, Italy) consists of 6 parallel recharge trenches with a depth of 1 m which are supplied with drainage water, pumped from an existing dewatering pumping station. Water infiltrates into the sandy soil through the trenches towards the aquifer. An incoming sediment control system (a mesh filter) has been installed upstream to the system.
The recharge trenches are placed between rows of poplar (White and Luisa Avanza species) and eucalyptus trees (Populus alba). In such forest areas, the water that infiltrates into the soil meets an effective filter made up of tree roots.
The depurative action occurs in the rhizosphere where, in conditions of almost oxygen-free soils and in the presence of abundant organic matter provided by the woody plants, the denitrifying bacteria, living in symbiosis with the roots, have a very effective action to promote nitrate attenuation. This function will be ensured in the medium-long term when the forested area is fully developed.
Considering that in the case of the Arborea pilot site, drainage water characterised by low quality is used for the aquifer recharge, the depurative action in the short term is ensured by an innovative Passive Treatment System installed on the bottom of the recharge trenches.
The Passive Treatment System consists of a mixture of inert and organic materials (e.g. eucalyptus wood chips), to promote the denitrification process, attenuate organic and inorganic contamination and prevent clogging processes at the infiltrating surface.
Fields of applications
The method is one of the mitigation options aiming at reducing nitrate groundwater contamination in the Nitrate Vulnerable Zones. The technique can be applied in similar hydrogeological contexts.
Beneficiaries
Water Authorities, Municipalities, Managing Authorities, farmers, householders, local population.
Preliminary knowledge required (if any)
Before designing such a kind of system, it is necessary to have a complete knowledge framework in terms of geology, hydrogeology and hydrogeochemistry in order to understand if the area meets the minimum requirements to be eligible for such an intervention.
References/online resources
CARLETTI, A., PIRASTRU, M., DEROMA,A., SESSINI, A., GHIGLIERI, G., ROGGERO, P.P. 2022. Forested Infiltration Area (FIA) Design in the Arborea Nitrate Vulnerable Zone (Sardinia, Italy). In: Naddeo, V., Choo, KH., Ksibi, M. (eds) Water-Energy-Nexus in the Ecological Transition. Advances in Science, Technology & Innovation. IEREK Interdisciplinary Series for Sustainable Development. Springer, Cham. https://doi.org/10.1007/978-3-031-00808-5_76 ;
Mastrocicco, M., Colombani, N., Salemi, E., Boz, B., Gumiero, B. (2016). Managed aquifer recharge via infiltration ditches in short rotation afforested areas. Ecohydrology, 9, 167–178. DOI: 10.1002/eco.1622.
Mezzalira, G., Niceforo, U., Gusmaroli, G. (2014). Aree forestali di infiltrazione (AFI): principi, esperienze, prospettive [Forested infiltration areas (FIA): principles, experiences, perspectives]. Acque Sotterranee - Italian Journal of Groundwater, AS10049: 055 – 060. DOI 10.7343/AS-087-14-0114
https://bpinventory.com/best-practice/forested-infiltration-area-fia-system
https://www.menawara.eu/course/view.php?id=19#section-2
Contacts
Alberto Carletti
📧 alberto.carletti@unica.it