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I am a Postdoc within the Earth Surface Science group of Prof. Karsten Kalbitz. We are part of the Institute for Biodiversity and Ecosystem Dynamics (IBED) of the University of Amsterdam .
I am interested in soil and in particular in soil organic matter .
My research focuses on processes controlling incorporation and accumulation of carbon within soils, and how they are impacted by anthropogenic activities.

Soil organic matter

Soil organic matter is the sum of the carbonaceous compounds of organic origin, present in a soil. Most of the organic carbon found in soil derives from plants. They uptake atmospheric CO2 by photosynthesis and their residues (leaves, branches, roots, and wood) are then incorporated into soil.
But, how does this work, what does really happen to leaves when falling aground?
Animals and microorganisms feed on them, breaking them down into small fragments, or even to simple molecules. These remnants become part of the soil forming its top most layer but also entering it, either as particles or dissolved in water. There they can become trapped within aggregates or adsorbed onto mineral surfaces, or they can be removed with the soil solution or serve as carbon and energy sources for microorganisms.
These processes are interlinked and take place simultaneously, but at varying rates, depending on climate, soil temperature, soil water content, soil type, soil parent material, vegetation type, and, of course,   human activities. The result is a modification of the physical location and the chemical characteristics of the organic matter, and in turn of its possibility to remain into (accumulate) or leave the soil (in solution or back as CO2).

My research

To study the mechanisms and triggering factors of soil organic matter formation, transformation and accumulation is very complex, therefore interesting and challenging, but also of great importance.
Soil is the second largest reservoir of carbon on Earth, and thus a key factor in global carbon cycling and the Earth's climate. Still on a global perspective the role of soil as source or sink of CO2 remains under debate, especially when related to different soil uses and managements.
Even more important, Humankind depends on soil. All life in terrestrial ecosystems ultimately depends on soil, and soil's ability to support life depends much on its content of organic matter. The indiscriminate use of soil has reduced soil organic matter content, endangering soil fertility and quality. Therefore we are in urgent need to know how to sustainably make the best use of the soil resource.
My research aims at understanding in which forms carbon resides in soil, which processes change or modify its characteristics, and in which time-scale they take place.
I am interested in studying natural environment to learn about how the processes work in nature. However, I also value simple laboratory experiments, to single out processes and learn how they work. Moreover, I'm studying the effects of anthropogenic activities by comparing natural and human-affected systems.
In all my research I use and develop fractionation techniques (in particular density fractionation) and analyses of bio-molecules (lignin-derived phenols, phospholipids fatty acids, amino sugars), in conjunction with general soil analysis as well as specific analytical techniques (13C NMR , FT-IR, IRMS).
Currently, I am setting up bio-molecule analyses at the IBED laboratories (phospholipids fatty acids, lignin-derived phenols, black carbon, amino sugars, neutral sugars and uronic acids), and I am doing research at two field sites.

Research sites

Torgnon

The first study we do in collaboration with the Regional Agency for Environmental Protection and the University of Turin. The study site is located in the municipality of Torgnon (Aosta Valley Region), in the north-west Italian Alps. We compare two snow-affected sites at a high elevation (above 2000m a.s.l.) close to the tree line, one in a larch (Larix decidua Mill.) forest, and one in an open meadow.
The sites are included within the European Long Term Ecological Research network, and are monitored year-round for trace gas emissions (CO2 , CH4 , N2O) using eddy-flux towers, snow-flux towers and chambers measurements. Moreover, periodical measurements of snow and soil solution characteristics are performed to track leaching processes and nutrient dynamics.

Our group focuses on the characterisation of soil organic matter and its dynamics.
By analysing a suite of bio-molecules (i.e. lignin, carbohydrates, amino sugars, lipids, phospholipids fatty acids), including their stable isotope ratio, we aim at tracking:
(i) changes in the microbial population during the winter season and the snow melt period;
(ii) changes in the characteristics of the organic matter in soil and in soil solution;
(iii) linking the changes to the seasonal emissions of biogenic gas.

Parco del Ticino

The second study is done in cooperation with the University of Pavia and the University of Turin . The site is located in the Ticino 's Regional Park (North Italy), a UNESCO Man and Biosphere area. It is one of the most important remains of the original ecosystem of the Po valley, characterized by a mosaic of typical fluvial ecosystems, with large river habitats, wetlands, riparian woods and patches of the primary plain forest that covered the entire valley during Roman colonization. In particular these forests are nowadays extremely rare because of the heavy human impact on the whole plain, especially after the Second World War. The study sites are constituted by a relict of such natural mesohygrophilous forest and a part of the same forest which was converted into poplar plantation in 1970.
Here we work on tracking the effect of land use change and management on soil properties and organic matter accumulation and distribution. Organic matter distribution is assessed by density fractionation and its characteristics by analysis of bio-molecules (i.e. lignin, phospholipids fatty acids, amino sugars, carbohydrates, black carbon) in the whole soil and in the separated fractions.

My background

Before arriving to Amsterdam, I worked at the Agricultural Chemistry and Pedology Sector of the Department of Agroforestry Resources (Di.Va.P.R.A.) of the University of Turin.
My passion for soil started during the first years of university, with courses in soil chemistry and pedology. While working on my MSc thesis and within the Erasmus exchange program, I studied soil organic matter in forest soils in Sweden and Denmark (along with Prof. Maj-Britt Johansson and Dr. Lars Vesterdal).
I graduated in Forestry and Environmental Sciences in 2003, and then started my PhD study under the supervision of Prof. Luisella Celi at Turin. I kept working on forest soils, partly within the EU-INCO project "Impacts and risks from anthropogenic disturbances on soils, carbon dynamics and vegetation in podzolic ecosystems". I spent a period of time at Halle (Germany; Prof. Georg Guggenberger), working on density fractionation and lignin characterization by CuO oxidation.

I defended my PhD thesis on "Sequestration of carbon over time in northern forest soils: organic matter chemical and physical stabilization" in January 2007.
Thereafter, I continued working as Research Assistant and then as Postdoc with Prof. Celi and the soil group at the University of Turin. My research activities included:
-          adaptation and application of P fractionation to track the biogeochemical cycle of P during pedogenesis along a forest soil chronosequence in NW Russia,
-          isolation of clay-sized minerals from a forest soil chronosequence in N W Russia for characterizing active mineral phases forming during soil development,
-          application of density fractionation and bio-molecule analyses to various soil systems under different management (pristine forests, biomass plantations, rice paddies, biofuel crops),
-          supervision of bachelor and master students.

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