#1Organic Carbon % 1 N m Soil organic carbon and land use in Veneto and Friuli Venezia Giulia (Northern Italy) CRA CONSIGLIO PER LA RICERCA E LA SPERIMENTAZIONE IN AGRICOLTURA Rosa Francaviglia, Gianluca Renzi and Anna Benedetti Consiglio per la Ricerca e la sperimentazione in Agricoltura, Centro di ricerca per lo studio delle Relazioni tra Pianta e Suolo, Via della Navicella 2-4, 00184 Rome, Italy [email protected]; [email protected]; [email protected] Soil System Sciences Division BACKGROUND AND MAIN FINDINGS The Italian Ministry of Agricultural Food and Forestry Policies (MIPAAF) has set up a statistical survey aimed to provide the national forecast of yields and areas related to the main Italian agricultural crops (AGRIT). The methodology is based on field surveys and remote-sensed data, covers yearly the whole national territory, and is based on 100,000 observations which are statistically selected from a predefined grid made up of about 1,200,000 georeferenced points. In 2011-2012 we determined the soil organic carbon content (SOC) of 1,160 sampling points situated in Northern Italy in the plains and hills of Veneto (VEN) and Friuli Venezia Giulia (FVG), for which the land use in the period 2008-2010 was known. Samples have been subdivided in three main classes: arable crops, orchards and fodder crops. SOC was higher in FVG samples (2.48%, n=266) than in VEN samples (1.90%, n=894). The average value (2.03%) is clearly affected by the higher number of VEN samples. st 7 6 5.65 FVG 3.41 I 2.72 2.48 2.32 2.19 2.08 2.06 2.03 1.53 1.47 fodder crops alfalfa vineyards I soybean-wheat maize maize-wheat I maize-soybean 3 yr rotations I soybean wheat all Organic Carbon % 4.00 VEN 3.50 3.00 2.50 2.00 1.50 3.13 m 1.00 0.50 0.00 2.46 fodder crops orchards soybean-wheat soybean-alfalfa land use change wheat-alfalfa alfalfa 1.59 H 1.56 H maize maize-alfalfa maize-wheat 1.55 H 1.53 H 1.45 H 1.43| H wheat maize-soybean 3 yr rotations soybean .37 le 1.90 H In FVG fodder crops (5.65%), alfalfa (3.41%) and vineyards (2.72%) showed the higher SOC content. SOC was 2.94% and 1.39 % in the grassed and no-grassed vineyards respectively. In the arable crops the average SOC was 2.18%, ranging from 2.32% (soybean-wheat rotation) to 2.03% (continuous soybean). SOC was 2.19% in the continuous maize, with 2.23% in corn and 1.87% in silage maize. The lower values were in the maize-wheat rotation (1.53%) and the continuous wheat (1.47%). In VEN the mean SOC value was 1.57% in arable crops, 2.46% in orchards (including vineyards, olive groves, and fruit crops), 3.13% in fodder crops. SOC in orchards was 1.82% (not grassed), 2.46% (grassed), 2.69% (mulched); 2.10 and 2.08% in the 2- yr rotations soybean-wheat and soybean-alfalfa respectively. SOC in the other arable crops was between 1.79% (land use change) and 1.37% (continuous soybean). A higher SOC was shown in VEN samples when comparing continuous corn (1.69%) and continuous silage maize (1.43%). 2.30 2.20 de 2.10 Organic Carbon % Organic Carbon % 4.0 Vineyards 3.5 3.0 2.5 2.0 1.5 2.94 1.0 0.5 0.0 2.00 1.90 2.23 1.80 1.70 1.60 Trentino A.A Friuli V.G. Valle d'Aosta Lombardia Veneto Piemonte Emilia Romagna Liguria Sardegna FVG 2.72 1.39 grassed not grassed all Continuous maize 1.87 corn silage maize all FVG 2.19 VEN VEN Organic Carbon% Toscana Marche Umbria Abruzzo Lazio Molise Puglia Campania Basilicata Organic Carbon % Sicilia Calabria Soil organic carbon % N m + 75; 6% FVG + VEN 263; 23% 822; 71% arable crops orchards fodder crops 6 FVG 5 5.65 2.72 1 2.18 0 arable crops orchards fodder crops 3.0 Orchards 2.5 2.0 1.5 2.69 2.46 2.46 1.0 1.82 0.5 0.0 not grassed grassed mulched all 1.7 Continuous maize 1.6 1.5 1.69 1.4 1.3 1.59 1.43 1.2 corn n silage maize all We did not inherit the Earth from our parents, we borrow it from our children (Navajo Proverb) Soil organic carbon% Soil organic carbon % 4.0 FVG + VEN 3.5 3.0 2.5 2.0 1.5 2.48 1.0 1.73 0.5 0.0 arable crops orchards 3.77 il fodder crops 3.5 VEN 3 2.5 2 3.13 1.5 2.46 1 1.57 0.5 0 arable crops orchards fodder crops CONCLUSIONS Data, even limited to two Regions, have clearly shown the positive contribution to SOC storage of orchards (mainly in grassed and mulched systems) and fodder crops, which are more conservative systems due to the lower soil disturbance from tillage operations; and to a lower extent of cropping systems with alfalfa or other legume crops. In particular, soybean-wheat rotation showed a higher SOC content than continuous wheat and soybean. CC BY