Agro-environmental Sustainability of Conventional and Organic Vegetable Production Systems in Tayabas, Quezon, Philippines

Environmental burdens of the different components of conventional and organic vegetable productions systems in Tayabas, Quezon were evaluated using the Life Cycle Assessment (LCA) approach. The study quantified the material inputs, outputs and emissions in a defined boundary, from land preparation to transport to market. Impact categories evaluated were global warming (GWP), acidification (AP), eutrophication (EP) and human toxicity (HTP) potentials based on the functional units of 1 kg and 1 ha production area. Conventional vegetable farming contributions to global warming potential was 2.12E-01 kg CO2 equivalent kg-1 of vegetable which was 43% higher than organic farming (1.21E-01 kg CO2 equivalent kg-1 of vegetable). Acidification potential of conventional (4.76E-03 g SO2 equivalent kg-1 of vegetable) was 23% higher than organic vegetable production (1.06E-03 g SO2 equivalent kg-1 of vegetable). Organic farming contributed 3.03E+00 kg PO4 equivalent kg-1 of vegetable potential eutrophication which was 16% higher than conventional with only 4.70E-01 kg PO4 eq kg-1 of vegetable. The application of chemical pesticides of conventional farms contributed to human toxicity potential calculated for both soil and air compartments. Cypermethrin had the highest total human toxicity in soil and air with 7.88E+06 g 1,4 DCB-eq ha-1 and 1.84E+02 g 1,4 DCB-eq ha-1, respectively. Organic farms had zero human toxicity potential in this study since organic farmers did not use synthetic pesticides.This study provided evidence on the possible environmental contributions to emissions of conventional and organic vegetable production systems