An indicator-based framework for the assessment of sustainability in paddy rice farms

A sustainability assessment is an evaluation of farm management in relation to defined objectives within the multi-faceted sustainability concept. The assessment requires i) a defined framework of themes (e.g. economic issues, environmental impact, resource consumption/maintenance…); ii) a list of specific indicators within each theme (e.g. yield, nutrient use efficiency, GHG emissions…); iii) defined methodologies to calculate indicators (e.g. IPCC guidelines, scientifically-proven estimators, e.g for NUE, N leaching, soil erosion…); iv) a calculation method that combines information into an overall judgement. Pooling all information into a single score inevitably causes a loss of detail and an inner compensation among contrasting trends. Nevertheless, a single concise final score can be used to compare various farms, and serve as a showcase for food chains where performance assessment is an added value. The variability of farm approaches to sustainability poses problems in setting the assessment framework. For instance, large intensive farms have different strategies from small extensive farms in marginal areas, but a comprehensive system should acknowledge efforts of both. Therefore, the choice of indicators, methodologies and weights are crucial aspects. In the context of a regional Operational Group that involved 10 farms, a sustainability assessment framework was developed for the evaluation of paddy rice farms. Three sustainability themes were included: environmental, territorial, and social. The first theme included indicators on agri-ecological value, biodiversity, pesticide use, gas emissions, and nutrients. The territorial theme included indicators on landscape elements, infrastructures, territorial protection, erosion and flood protection. Finally, the social theme included indicators evaluating local food chains, social function, tourism, culture and economic function. The above indicators were valued in a 0-1 scale. Some of these were numerical, and their values were scored according to specific criteria; e.g. N surplus was scored 1 if its value was within ±20 kg ha-1 yr-1, and 0 in all other cases, N2O emission was 1 if <2.5 kg ha-1 yr-1 and 0 if above. Other indicators were categorical, as adopting (1) or non-adopting (0) a good practice, e.g. maintenance of wetlands, invasive species control, hedges, historical buildings. The sum of (weighed) single indicator values was then standardized and expressed in a 1-4 scale, and summed up (weighed) to an overall farm score, expressed on four classes (A-D) and three sub-classes (+, 0, -) coupled to a colour, similar to the EU energy label. Specific weights can be assigned to indicators within groups and to groups within the final score, thus allowing also a different importance of themes in contributing to the final score. The assignment of weights includes political issues and will be defined at a later stage. In practice, the framework is a web platform where farmers can insert productive and management data, and obtain the final score. The framework can be used as a basis for a production specification document and a certification system. The system also allows a traceability of farm operations and practices, as well as tracing and monitoring the change of indicator values or score with and without the adoption of each practice.