Agronomic operations

Evaluation of the greenhouse-gas reduction efficacy of a rapeseed (Brassica napus L.) biofuel crop and impact of agronomic techniques

L. Belelli Marchesini (1), R. Casa (2), D. Papale (1), F. Pieruccetti (2), P. Stefani (1), N. Arriga (1), F. Mazzenga (1), and R. Valentini (1).

(1) Department of Forest Science and Resources, University of Tuscia, Italy.(2) Department of Crop Production, University of Tuscia, Italy.

Tr

AWUEPh

FOCUS ON THE GHG EMISSION REDUCTION EFFICACY OF BIOFUELSThe need of using ecologically friendly fuels as a remedy to tackle climate change effects and as an answer to growing costs of petroleum, has encouraged the production of biofuels in the latest years (Farrel et al. 2006). Biofules are a clean source of energy produced from biomass such as wood, energy crops, energy wastes and residues, accounting for approximately 11% of total primary energy consumed globally and for about 80% of renewable energy (GBEP, 2007).Biofuel life cycle analysis is used to evaluate environmental impact and potential factors related to product life cycle energy balance, including raw material, production, consumption and waste utilization. Fuel is considered not renewable if the amount of fossil fuel energy used in production is significantly higher than accumulated in the product, i.e the ratio of biofuel energy (calorific value) to the total energy used for fuel production, is less than 1 (Janulis, 2004).Rapeseed oil is a renewable fuel, the oil is obtained by an annual plant, and all the carbon released by combustion has been fixed by the plant trough the process of photosynthesis. However for a complete analysis of the carbon cycle additional information relative to various processes required to produce and convert the material into useful forms.If most of biofuels were found to reduce green-house gas emissions by more than 30% relative to gasoline (Zah et al., 2007), the debate about the production of biofuel crops should also focus on the overall assessment of its environmental costs and benefits. Such an analysis should take into account a comparison between a land dedicated to energy crops and traditional land-use scenarios, especially whether native ecosystems are destroyed to produce biofuels, but also verify the balance of green-house gases for a determined biofuel crop along its whole productive cycle.

Meteo data

CO2 Fluxes, ecological parameters

Remote sensing NDVI, LAI, fPAR

ANN,models

Remote sensing GPP

Air borne measurements

Inventories

Phytopathology, Fire

Trace gases in agricultural and forest ecosystems

Kyoto-oriented policiesFuture scenarios

LINE I: Flux measurement

and up-scaling

LINE V: Policy and scenarios

LINE IV: Non CO2 trace gas fluxes

LINE II: Regionalization

LINE III: Experimental verification

National Sink

CARBOITALY Research lines

CCC

Deciduous Forests

Croplands

Evergreen Forests

Forest Plantations

Maquis

Pastures and Meadows

THE CARBOITALY PROJECTCarboitaly is a project financed by the Italian national fund for research (FISR) aimed at quantifying, through appropriate methods and a solid scientific approach, the carbon sequestration by agricultural and forest ecosystems at national scale in Italy. Theobjective of the project is to organize and manage the GHG flux measurements network in Italy, being formed at present by 20 sites over 11 regions. All data collected from sites are integrated in a project database.

Measurement of fluxes and environmental parametersThis activity includes continuous and long term monitoring of CO2 fluxes in different types of ecosystems in Italy as well as all the ancillary parameters concerning physical and chemical properties of air, soil and biomass.In particular mandatory measurements include fluxes of carbon dioxide, water vapour, and sensible heat by eddy covariance (EC) technique, net radiation, soil heat flux, vertical profiles of air temperature and humidity. In respect with the environmental parameters each site provides measurements of soil water content and temperature and of ecophysiological parameters of vegetation.Inventory measurements include the characterization of carbon pools, particularly the assessment of soil carbon stocks, and the quality of soil carbon through its fractionation in different pools by dimension and density.

No tillageTillage

Rocca 3 (tillage) Rocca 4 (no tillage) Variable Sensor type Sensor model measurement heightX X Net radiation Net radiometer RebsQ7

X Air temperature Termometer TE -TTU600 h: 2mX Air humidity Hygrometer TE -TTU601 h: 2mX PAR PAR radiometer Skye SKP 215X diffuse PAR PAR radiometer Skye SKP 215

X Global radiation Pyranometer Skye SKP 1110X diffuse global radiation Pyranometer Skye SKP 1110X Rain Rain guage TE ARG 100X X Soil heat flux Heat flux plate Rebs HFT-3 h: -5 cmX X Soil temperature thermistor Campbell Scientific 107X X Soil water content TDR Campbell Scientific 616 h: -5, -15, -40, -70 cm

Mean daily CO2 fluxes (8-19 Nov 07)

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Fc

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tillage

no tillage

Eddy covariance and environmental monitoring

Main parameters of crop monitored over the whole coltural cycle

Parameter Frequency Method

Total aboveground biomass

including weeds

30 d Gravimetric

Crop height 30 d Metric

Density 30 d Count

Total belowground biomass

including weeds

2 times/cycle Soil cores

Root depth 2 times/cycle Soil cores

Crop yield End of cycle Gravimetric

C , N of culture and weeds 30 d Bichromate-Kjeldhal; Elemental analyzer

Soil cover 10-15 d Soil segmentation utility supervised

classification (Dycam ADC, digital camera

VIS)

LAI (Leaf Area Index) 30 d Direct method (Area meter Li-3100)

LAI (Leaf Area Index) 10-15 d Indirect method (PAR ceptometer)

Intercepted PAR 10-15 d PAR ceptometer

Soil cover Brassica napus

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31-Dec-07 15-Jan-08 30-Jan-08 14-Feb-08 29-Feb-08

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il c

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[%]

Tillage

No tillage

Crop and weeds

growth monitoring

EXPERIMENTAL ACTIVITIESUnder the framework of the CARBOITALY project, two paired experimental sites for the monitoring of CO2 fluxes by eddy covariance technique over rapeseed (Brassica napus L.) biofuel crops in the province of Viterbo (Italy) were established in fall 2007. The experimental activities aim at the comparison between a tillage and no tillage agricultural managements in respect with the greenhouse gas balance of the crop systems accounting for all removals and emissions (direct and indirect) during the productive cycle. Moreover the activities cover a wide range of observations of biophysical parameters in the soil, plant, atmosphere compartments to evaluate the effect on the environment of the two agricultural managements

Date OperationTreatment

01-03/09/2007 Ploughing (depth 30cm) T

26/09/2007 Fertilization ( 50 kg/ha P2O4) T

01-03/10/2007 Tillage (depth 15-20 cm) T

08/10/2007 Weeding - Glifosate (3L/ha) NT

10/10/2007Sowing Rapeseed (var. Sartori) (depth 2 cm, rows spaced 36 cm) + fertilization ( 50 kg/ha P2O4) NT

11/10/2007 Sowing Rapeseed (var. Sartori) (depth 2 cm, rows spaced 36 cm) T

20/11/2007 Weeding after seedling emergency (metazaclor -butisan S 2L/ha) NT

20/12/2007 Weeding after seedling emergency (clopiralid -Lontrel 75 130g/ha) T

14/03/2008 Fertilization - Urea ( 70 kg/ha di N) T+NT

14/03/2008 Weeding (Haloxifop-R-methyl ester -Gallant 30W 2.5/ha) NT

15/03/2008Weeding (Haloxifop-R-methyl ester -Gallant 30W 2.5/ha and Clopiralid -Lontrel 75 186g/ha ) T

30/05/2008 Expected rapeseed harvesting NT+T

Info: belelli@unitus.it