Jacopo Bacenetti, Marco Negri, Marco Fiala, Stefano Bocchi

Transcription

1 Life Cycle Assessment of Organic Rice Production System in Northern Italy Jacopo Bacenetti, Marco Negri, Marco Fiala, Stefano Bocchi Department of Agricultural and Environmental Sciences. Production, Landscape, Agroenergy. University of Milan Via Giovanni Celoria 2, 20133, Milan, Italy Keywords: Environmental impact; sustainability, methane emissions; Italy. DIPARTIMENTO SCIENZE AGRARIE E AMBIENTALI. PRODUZIONE, TERRITORIO, AGROENERGIA

2 INTRODUCTION & AIM Life Cycle Assessment (LCA) is a methodology to assess the potential environmental impacts and resources consumption associated with a production system considering all the stages of a product's life from cradle to grave. The term life cycle refers to the notion that a fair, holistic assessment requires the evaluation of raw-material production, manufacture, distribution, use and disposal including all intervening transportation steps necessary or caused by the product's existence

3 INTRODUCTION & AIM Originally developed to analyze industrial processes, nowadays, asses the environmental impact of agricultural systems. the LCA is applied also to According to the ISO and standards, a Life Cycle Assessment is carried out in four distinct steps: GOAL AND SCOPE DEFINITION LIFE CYCLE INVENTORY IMPACT ASSESSMENT 4 steps TATION TS INTERPRET RESULT STEP 1: GOAL DEFINITION Definition of the study aim, the system boundary (what is included and what is not) and the functional unit (a measure of the function of the studied system and it provides a reference to which the inputs and outputs can be related) STEP 2: INVENTORY ANALYSIS Data collection about input and output for all the processes involved in the production cycle STEP 3: IMPACT ASSESSMENT Transformation of inventory data in environmental impact STEP 4: INTERPRETATION Identification of possible mitigation strategies

4 WHY a LCA? + +advantage of LCA To consider the whole life cycle of a product To quantify the environmental impact by means of numeric indexes To identify the environmental hotspots To compare similar products produced by diverse production processes To identify the most environmental fi friendly solutions What does «impact assessment» mean? Which environmental impacts are evaluated? CLIMATE CHANGE Some important EUTROPHICATION (water) environmental issues are ACIDIFICATION not evaluated. (soil) E.g., g, TOXICITY (human and water) BIODIVERSITY RESOURSE DEPLETION (mineral, fossil) RADIOACTIVITY

5 AIM To assess the environmental profile of organic rice cultivation in Northern Italy and to identify the key processes from an environmental point of view. GOALS: What is the environmental impact for 1 ton of grain from ORP system? What are the processes most responsible for this impact? TRAD Compared to traditional rice production system (characterized by higher yield) which rice system show better environmental performances?

6 Green Manure SOWING VETCH RYEGRASS S Crop Management MECHANICAL WEED CONTROL (4 times) FLOODING W Field Preparation Sowing ORGANIC FERTILIZATION C PLOUGHING HARROWING SOWING Harvest and storage HARVESTING TRANSPORT 2.45 km S DRYING ORP SYSTEM DESCTIPTION In autumn, a mix of vetch th and ryegrass is sown; in the following May the biomass is incorporated into the soil. Rice sowing is carried out with a precision seeder (220 kg/ha of seed - depth of 5-6 cm) after tillage operations. Weed control is performed using a spring tine harrow (4 interventions). After it, the rice fields are flooded and no aerations are scheduled. The flooding ends only at the beginning of September. Harvesting operations carried out with self-propelled p harvester and rice paddy is transported to the farm. The straw is left into the soil

7 SYSTEM BOUNDARY The following activities were included in the analysis: manufacture and use of the agricultural inputs (e.g., fuels, seed, fertilizers and agricultural machines), maintenance and final disposal of machines emissions related to organic matter decomposition, fertiliser application and fuel combustion INPUT OUTPUT Seed, Diesel fuel, Lubricant, Tractor, Implements. Green manure Emissions in water, air and soil CH 4 4, N 2 O, NH 3 3, fuel combustion emissions Seed, Diesel fuel, Implements, Tractor Lubricant, Org.Fert Soil tillage & Sowing Emissions in water, air and soil fuel combustion emissions Diesel fuel, Tractor, Implements, Water Lubricant. Crop management Emissions in water, air and soil CH 4, N 2 O, NH 3, fuel combustion emissions Diesel fuel, Lubricant, Tractor, Implements. Harvesting & Storage Emissions in water, air and soil Combustion emissions emissions Grain and straw

8 INVENTORY DATA: Crop cultivation Data concerning ORP were obtained via questionnaires and surveys to farms and interviews with farmers and technicians. Section (A) Green manure (B) Soil Tillage & Seeding (C) Crop management (D) Harvesting & Storage Field Operative Operation machine Tractor Fuel Consumption Input Time kw kg kg ha -1 Product Amount h/ha Sowing Seeder Seeds Organic fertilization Manure spreader 140 kg ha -1 ryegrass 60 kg ha -1 vetch Compost 22.5 t ha -1 (b) 5.05 Ploughing Plough Harrowing Rotary harrow Sowing Seeder Seeds 220 kg ha -1 rice 0.86 Mechanical weed control Water management Harvest Harrow tines (c) Water m 3 ha -1 - Combine harvester t ha -1 (27% of moisture) Transport Trailer Transport Trailer Drying Dryer A grain yield 4.50 t/ha at commercial moisture (5.3 t/ha at 27% of moisture, about 33% lower respect to conventional rice) was considered. Sistema d Informazione Nazionale sull Agricoltura Biologica, 2015 (

9 INVENTORY DATA: Methane emissions Rice cultivation is responsible for considerable emissions of GHG in particular of methane produced during the decomposition of organic matter in anaerobic conditions. As regard to the CH 4 emissions, the methodology proposed by the IPCC was considered. Methane emissions are evaluated considering: Amount of organic matter introduced into the soil STRAW ORGANIC FERTILIZER GREEN MANURE Number of aerations during the crop cycle (no aerations are scheduled) Duration of flooding Methane emissions increase with higher application of organic matter and longer flooding. Methane emissions decrease with aerations, reduction of flooding, reduction of organic matter application.

10 ENVIRONMENTAL IMPACT ASSESSMENT As regard to ORC system the following 9 environmental impacts were evaluated: Climate change (Global warming potential) Ozone depletion Human toxicity, cancer effects Acidification Terrestrial eutrophication Freshwater eutrophication Marine eutrophication Freshwater ecotoxicity Mineral, fossil &ren resource depletion ILCD 2011 Midpoint V1.01 Simapro

11 RESULTS: Absolute values Impact category Unit Score Climate change kg CO 2 eq 1595 Ozone depletion kg CFC-11 eq Human toxicity, cancer effects CTUh Photochemical ozone formation kg NMVOC eq Acidification molc H+ eq Terrestrial eutrophication molc N eq Freshwater eutrophication kg P eq Marine eutrophication kg N eq Freshwater ecotoxicity CTUe Mineral, fossil & ren resource depletion kg Sb eq And now? OF RICE GRAIN However, besides the absolute values, it is important also TO IDENTIFY which processes, over the whole production system, are most responsible (hotspots) for the environmental impact of organic rice production. The hotspot identification is the prerequisite for the development of solutions able to reduce the environmental impact.

12 Relative cont tribution (%) Grain drying Emissions from fertilizer Methane emission Mechanization Green manure seed Rice seed organic CC OD HT TA TE FE ME FEx MFRD RESULTS: Hotspots Seed production (both for green manure and rice) are relevant for freshwater ecotoxycity Mechanization of field operation is an hotspots for MFRD, OD and HT mainly due to emission from fuel combustions CH 4 emissions are responsible for about 87% of CC Emissions due to fertilizers application are hotspots for eutrophication and acidification

13 Comparis son (%) Organic rice production system RESULTS: Comparison with traditional rice Traditional rice production system For HT, FE and Fex, the ORP achieves better performances (from -55 to 95%) due to the avoided application of mineral fertilizers and pesticide CC OD HT TA TE FE ME FEx MFRD Respect to traditional system, ORP shows higher environmental impact (about twice) for CC (due to higher CH 4 emission, TA and TE (due to emissions of NH 3 and NO 3 from fertilizer application ). For OD, ME and MFRD the results are similar. However, for MFRD the impact of ORP is slightly better TRP where weed control is performed also with chemical treatments

14 CONCLUSIONS Generally speaking, the environmental performances of ORP system are affected by the lower grain yield (-33%), differences about the two production systems will be smaller if the results will be referred to the cultivated area (Functional Unit = 1 ha) It is noteworthy that, for toxicity related impact categories (human and freshwater ecotoxicity) and for freshwater euthophication, the environmental impact of rice paddy from ORP is reduced respect to TRP In the future the improvement of the cultivation practice and the consequently yield increase could improve environmental performances of ORP. As regard to methane emissions (affecting CC the most well-know impact category), a possible mitigation strategy t is represented by the introduction ti of aerations (but yield reduction could occur) THANK YOU FOR YOUR ATTENTION