About Dr Federico Maggi

Within the Group of Fluids and Environment at University of Sydney, Federico's expertise is mainly focused on environmental modelling. Federico’s research interests include environmental fluid mechanics, hydraulics and ecohydrology, biogeochemistry, sediment-water interaction, soil-plant-atmosphere interaction, reactive flow and transport in soils, soil change, isotope methods, climate change, water resources and quality, sustainable agriculture, bio- and phyto-remediation.

Federico obtained his MSc in 1999 from the Polytechnique of Turin, Italy, with a thesis on nonlinear prediction of complex signals from deterministic chaos and turbulence. He received his PhD in 2005 from the Delft University of Technology, The Netherlands, with a comprehensive experimental and modelling work on turbulence-induced flocculation of suspended cohesive sediment. In 2005, Federico moved to Duke University, North Carolina, USA, where he became involved in advanced mathematical modelling of soil fluid mechanics. In 2006, Federico obtained an appointment at the University of California, Berkeley, USA, where his interests widened to soils physics, biogeochemistry, and environmental modeling. Since 2006, Federico joined the Earth Science Division at the Lawrence Berkeley National Laboratory, Berkeley, USA, where he is currently guest scientist.

Current research projects

Biological flocculation of suspended cohesive sediment
: a new, innovative facility built in the Fluids Lab is used to carry out optical observations of the interaction between suspended sediment and micro-organisms. The experimental data are used in conjunction with a modified population balance equation based on the Smoluchowski equation.

The theory of kinetic isotopologue and isotopomer speciation and fractionation
:a new theory of biochemical isotope fractionation has allowed us to open new perspectives on elemental exploitation, movement, and release in soil microbial communities. Integration of this approach into mechanistic models of soil biogeochemistry is being carried out.

Global soil change
: the change in food consumption patterns which are globally occurring since the past 50 years has radically changed the agriculture and farming practices, causing enormous consequences on soil quality (e.g., carbon and biodiversity loss, deforestation, desertification, etc.). Minimalistic and mechanistic models are developed to assess the rate of soil change at field, watershed and continental scales.

Radiocarbon modelling
: radioactive carbon produced during nuclear bomb tests in the sixties provides a detectable marker to understand the turnover time of carbon stored in soils. A new modelling framework for non-steady-state systems is being developed to assess carbon storage and release rate to the atmosphere caused by perturbations introduced, for instance, by human activities, climate change, agriculture, invasive species, etc.

Plant disease dynamics
: the spreading of phytopathogens from insects threatens plants and crops in natural and managed ecosystems. For agricultural purposes, experimental and theoretical modeling are carried out to understand the dynamics of disease inoculation, incubation, and spread within the framework of nonlinear population dynamics.

Selected publications

  • Maggi F. and W.J. Riley, Transient competitive complexation in biological kinetic isotope fractionation explains non-stationary isotopic effects: Theory and application to denitrification in soils, Journal of Geophysical Research - Biogeosciences (in press).
  • Maggi F., Bioflocculation of suspended particle matter in nutrient-rich aqueous ecosystems, Journal of Hydrology doi:10.1016/j.jhydrol.2009.07.040.
  • Gu C., Maggi F., W.J. Riley, G.M. Hornberger, T. Xu, C.M. Oldenburg, N. Spicher, N.L. Miller, R.T. Venterea and C. Steefel, (2008), Aqueous and gaseous nitrogen losses induced by fertilizer application, Journal of Geophysical Research – Biogeosciences, doi:10.1029/2008JG000788 (in press).
  • Maggi F., (2008), Projection of compact fractal sets: application to diffusion-limited and cluster-cluster aggregates, Nonlinear Processes in Geophysics 15, 1-5.
  • Maggi F., Gu C., W.J. Riley, G.M. Hornberger, R.T. Venterea, T. Xu, N. Spicher, C. Steefel, N.L. Miller and C.M. Oldenburg, (2008), A mechanistic treatment of the dominant soil nitrogen cycling processes: Model development, testing, and application, Journal of Geophysical Research – Biogeosciences 113, doi:10.1029/2007JG000578.
  • Maggi F., (2007b), Stochastic flocculation of cohesive sediment: Analysis of floc mobility with the floc size spectrum, Water Resources Research 44(1), doi:10.1029/2007WR006109.
  • Maggi F. and A. Porporato, (2007), Coupled moisture and microbial dynamics in unsaturated soils, Water Resources Research 43, doi:10.1029/2006WR005367.
  • Maggi F., F. Mietta and J.C. Winterwerp, (2007), Effect of variable fractal dimension on the floc size distribution of suspended cohesive sediment, Journal of Hydrology, 343(1-2), 43-55.
  • Maggi F., (2007a), Variable fractal dimension: A major control for floc structure and flocculation kinematics of suspended cohesive sediment, Journal of Geophysical Research – Oceans 112(C7), 10.1029/2006JC003951.
  • Maggi F., A.J. Manning and J.C. Winterwerp, (2006), Image separation and geometric characterisation of mud flocs, Journal of Hydrology 326(1-4), 325-348.
  • Maggi F. and J.C., Winterwerp, (2004), Method for computing the three-dimensional capacity dimension from two-dimensional projections of fractal aggregates, Physical Review E, 69(1), 011405.