Comparison of Environmental Effects of Conventional and Low Input Saffron Production Systems in Razavi Khorasan by Using the Life Cycle Assessment Methodology

IntroductionOver the past few decades, agriculture has experienced rapid intensification in agricultural ecosystems. Although, this production pattern has significantly improved the yield of some crops, but has also led to an uncontrolled increase in the consumption of various chemical inputs. Agricultural activities are always dependent on natural resources and therefore have complex relationships with the environment. Evidence shows that the negative consequences of these activities, which are due to increased application of chemical inputs (such as fertilizers and pesticides) and fossil fuels, land use change and tightening of agricultural operations, increase the incidence of pollution. Global warming and climate change, natural habitat loss and endangered biodiversity. Indigenous knowledge is well recognized for its contribution to global warming and climate change adaptation strategies, and natural resource conservation. The present study aimed to compare the environmental impacts of low input (as a local production system) and conventional (as a high input farming system) saffron systems in Razavi Khorasan province, Iran. Materials and MethodsThe required data related to saffron yield and management methods in low input and conventional systems in Razavi Khorasan province were collected from the Ministry of Jihad Agriculture, saffron farmers and different organizations in charge of agriculture. Data (as a 7-year perennial crop) were collected by using a face-to-face questionnaire. Four phases, such as goal and scope definition, inventory analysis, impact assessment, and interpretation, were designed to assess the life cycle indicator based on the ISO14044 procedure. Four main categories as impacts, including global warming, acidification, and eutrophication (terrestrial and aquatic) were defined. The functional unit was considered as a one-kg flower yield. N2ODirect, N2OIndirect, N2Oleaching, and N2Ovolatilization were computed for the production systems. K2 and Pearson coefficients were computed. Results and DiscussionThe results showed that the conventional system's flower yield was higher than the low input farming system, up to 71 percent. Aquatic eutrophication potential for the conventional system was computed with 15.07 kg PO4 eq./ per kg of flower higher than other management systems up to 34%. Environmental indicators for low input and conventional production systems were calculated with 2.72 and 3.51 Ecox per per kg of flower, respectively. The share on impact categories such as global warming, acidification, terrestrial eutrophication, and aquatic eutrophication were calculated with 16, 7, 8 and 69 percent from the conventional system's Ecox. The values were computed with 17, 7, 8, and 68 percent from the low input system's Ecox. The relationship between flower yield and fuel, nitrogen and fuel, nitrogen and phosphorus, and manure and yield was significant. The highest Pearson coefficient was calculated for flower yield and fuel with +0.824. The amount of CO2 emission in the low input system was equal to 312.15 kg equivalent of CO2 per kg of flower yield, which was 95% higher than the conventional system. On the other hand, the emissions of CH4 and N2O in the conventional system were 322.88 and 4913.94 kg, respectively, equivalent to CO2 per kg of flower yield, which is 31 and 28% higher than the emissions of these greenhouse gases in the system under management was low input. The global warming potential for the conventional management system was equal to 5262.67 kg equivalent of CO2 per kg of flower yield, which was 18% higher than the low input system. ConclusionBased on the results, it is suggested that the implementation of conservation tillage methods, consumption of low inputs and more efficient irrigation systems be used in saffron production systems, which reduces consumption of fossil fuels as well as soil low input matter recovery and in the long run can have a significant impact on reducing the use of chemical fertilizers, especially nitrogen fertilizers. The integration of conservation tillage, indigenous knowledge, and traditional management based on women farmers are valuable contributions for global warming and climate change strategies, sustainable agriculture, natural resource and water management conservation especially in high input saffron agroecosystems.