Is Agriculture Always a GHG Emitter? A Combination of Eddy Covariance and Life Cycle Assessment Approaches to Calculate C Intake and Uptake in a Kiwifruit Orchard

A synthesis of the evidence regarding the efficacy of alternative field management practices in rice cultivation using life cycle assessment

Field management practices are an important factor in mitigating climate change and increasing agricultural production. However, no study has synthesized the evidence on the efficacy of alternative field management practices and reviewed life cycle assessments that consider all emissions over the entire or part of the life cycle of rice production. Thus, 68 papers were reviewed and grouped into 13 field management categories. The management practices were evaluated in terms of yield, area-scaled greenhouse gas (GHG) emissions, and yield-scaled GHG emissions against base management practices. The yield increase of these field management practices was between -6 % and 12 %, with some exceptions. It was only nonpuddling that simultaneously increased the yield and reduced both the area-scaled GHG and yield-scaled GHG emissions with respect to the base category. Water management, including alternate wetting and drying or single and multiple drainage and no-tillage, performed well in reducing the average area-scaled GHG and yield-scaled GHG emissions, although the average yield was reduced slightly. For the remaining many management practices, the increase in area-scaled GHG emissions was larger than the change in yield, so the yield change had little impact on yield-scaled GHG emissions. The higher increase in area-scaled GHG emissions than the change in yield requires innovative and new approaches, such as implementing alternative management together with water management, of which the effect was observed in some of the papers reviewed in this study. Therefore, this study recommends selecting nonpuddling, water management or no-tillage as climate mitigation management options. The evaluation of field management will be more robust if more impact categories are considered, including missing aspects (i.e., soil fertility).

Energy budget, carbon and water footprint in perennial agro and natural ecosystems inside a Natura 2000 site as provisioning and regulating ecosystem services

Energy flows in perennial agro and natural ecosystems are essential and could be related to greenhouse gas emissions and increasing water demands. Energy indices and carbon and water footprint are useful tools in assessing the interaction between production systems and environmental impact inside Natura 2000 sites and enhancing ecosystem services. The main aims of this study were to determine and compare energy indices, carbon and water footprint of olive groves, orange and kiwi orchards, and grasslands within and between 2 years, located in a Natura 2000 site, using an adjusted life cycle assessment (LCA) method; and to illustrate the importance of farming systems to ecosystem services. Proportional stratified sampling was used to select 36 farm types (12 olive groves, 12 oranges, and 12 kiwi orchards) and 12 grasslands from the municipality of Amfilochia, western Greece, during 2018 and 2019. Descriptive data analysis, correlational analysis, ANOVA, and hierarchical cluster analysis (HCA) were used to summarize and analyze the data. The main energy contributors for the three farm types were fertilizers and fuel consumption. The only input for the grasslands was animal manure. Energy efficiency showed the highest performance in olive groves followed in descending order by kiwi orchards, grasslands, and orange orchards. Concerning carbon-footprint, the values were the highest for orange orchards, followed in descending order by kiwi orchards, olive groves, and grasslands. Total water footprint values were the highest for grasslands and the lowest for olive groves. For both years, regarding HCA, each cluster consisted of the same ecosystems. According to the abovementioned indices, olive groves and grasslands are the most environmental friendly ecosystems. They could contribute in the environmental protection of the Amvrakikos Gulf, a Natura 2000 site. Kiwi orchards, although they are intensive along with the orange ones, seem to be more friendly to the environment than them and their cultivation in this Natura 2000 area is recommended. Energy indices and carbon and water footprint could be used, in order to highlight the related ecosystem (dis)services.