1. Introduction
Today, there is growing interest in assessing the sustainability of agriculture. Sustainability has become a high priority, both in scientific research and in policy agendas [
1]. Despite the existence of many studies examining particular dimensions, the need for an integrated assessment of sustainability at the farm level has been widely recognized in scholarly research [
2,
3,
4,
5,
6,
7,
8,
9]. This realization is a result of the sustainability concerns of citizens, as well as frequent policy changes, which create new information needs for all sustainability dimensions at the farm scale [
10,
11]. In the concurrent consideration of the multifaceted nature of sustainability at the farm level, diverse methods for the measurement of indicators and the aggregation of scores have been used [
12,
13]. The most frequently used methods include tools, frameworks, and indices based on indicators. These are followed by multi-criteria methods, including the analytical hierarchy process (AHP) [
9,
14,
15,
16,
17,
18].
However, the above task is hampered by the complexity of the sustainability concept and the heterogeneity of agricultural systems [
19], as well as the limited availability of data, which could possibly allow the calculation of meaningful and relevant indicators [
20]. Besides the lack of data at the farm level, recent research has pointed out the need to broaden the scope and complement well-established monitoring tools, such as farm accountancy data networks (FADN) [
10,
20]. Also, any effort for the assessment of sustainability involves various controversial issues, including the process of computing composite indicators, which encompass much information from multiple indices [
6,
9,
11].
The sustainability assessment of Greek agriculture is crucial and could provide vital information for an appropriate strategy that will support its improvement. Greek agriculture features a high degree of sectorial and spatial heterogeneity, as well as a prevailing small-scale structure. In addition, various farming systems of crucial importance are extensive. For example, the average density in olive orchards is 139 trees per hectare (ha), which is much lower than the threshold of intensive systems (more than 180 trees per ha) [
21,
22]. Similarly, the extensive production system is dominant in sheep rearing, with 78% of the Greek sheep flocks being reared in low-input production systems [
23]. On the other hand, Greek agriculture presents some noteworthy distinctive features compared to the majority of EU countries, such as the highest share of permanent crops (tree cultivations and vineyards) in the total utilized agricultural area (UAA) among EU countries [
24], as well as large numbers for sheep and goat rearing, mainly for the production of dairy products rather than meat.
As a part of the broader Mediterranean region, Greek agriculture is facing a series of challenges with clear sustainability implications, such as fragile social structures, the intensive exploitation of natural resources, increasing risks of droughts and biodiversity loss, decrease in crop yields, and rising demand for water [
25,
26]. At the same time, the long-term viability of farms is in jeopardy, all the more so because most of them are small and are less powerful actors in a rapidly consolidating agri-food system. All these challenges undoubtedly imply a necessity for a multidimensional sustainability assessment at the level of farms. It has to be noted that, with a few exceptions [
27,
28,
29], the literature on this critical issue is scant in regard to Greek agriculture.
This study aims to conduct a comparative assessment of the sustainability performance of various agricultural sectors by using an AHP method to aggregate sets of economic, social, and environmental sustainability indicators. To this end, we use data from different sources, including farm-level data from FADN, complemented with additional data from the EU FLINT project (Farm Level Indicators for New Topics in policy evaluation), along with expert opinions and stakeholder views. This synthetic approach is applied across the professional farms of four typical farming systems in Greece, i.e., arable crops, olive trees, permanent crops, and livestock. All these sectors account for nearly half of the total output of Greek agriculture [
30], while they are vital for many rural areas of the country. In addition, these systems are characteristic not only for Greece but also for many other Mediterranean countries.
The paper is organized as follows. Firstly, the applied methodology and the data used in the study are described. Secondly, the empirical application is then presented, followed by the discussion of the results. Finally, the paper concludes by reporting the main findings.
4. Discussion
This study contributes to filling a gap in the integrated assessment of farm-level sustainability for some critical Greek farming systems. It is worth mentioning that two of the examined systems concern permanent crops, for which only a few sustainability assessment methods have been applied so far [
57]. A series of methodological and empirical issues emerge from the preceding analysis.
Sustainability assessment is not an easy task, especially when it is conducted across all pillars and through composite indicators. Composite indicators are easy to interpret, while they convey and summarize valuable information in complex, multi-dimensional issues. On the other hand, their interpretation could be ambiguous, because they can send misleading policy messages [
58]. Two further problems are the subjectivity of the process of assigning weights to individual indicators, which, along with their aggregation, is the essential stage in the process of constructing composite indicators [
59]. This ambiguity is mitigated by the fact that the opinions of experts reflect, at least to some degree, the “preferences” of the society on the debated and multi-faceted issue of sustainability. Therefore, future research could broaden the pool of experts (whose opinions are used to assign weights to separate indicators) with other stakeholders from the agri-food system, such as policymakers, farmers, cooperative members, etc. Additionally, future research should include small farms, which make up the backbone of Greek agriculture.
Taking into account the appeal for broadening the datasets of the established monitoring tools [
20], we have shown that the enrichment of FADN data with a series of farm-level information from the FLINT project, concerning environmental and social aspects of farm functioning, provides a meaningful set of indicators that enable a thorough sustainability assessment.
Assessing sustainability at the farm level is a powerful tool that can be used for a variety of purposes, such as the improvement in the governance of the agricultural sector [
59] and the facilitation of the marketing of food products [
60]. It can also support farmers to carry out detailed diagnoses to find the strengths and weaknesses of farms, thus contributing to the construction of a viable farm development plan. Also, the findings of this study can prove useful in identifying the actions needed to ensure the long-term sustainability of the examined systems, as well as in the formation of strategies for sustainable development in both sectoral and spatial terms.
A significant finding of this research is that although arable crop farms have received relatively more financial support over time, mainly in the form of direct payments, they have not been able to reduce the gap in the criterion of economic performance significantly. Similarly, while the agri-environmental measures in Greece were applied primarily to arable crops, our analysis shows that arable crop farms lag behind other sectors in terms of environmental performance criteria.
Moreover, Prosperi et al. [
61] claimed that the high sustainability performance of agri-food systems implies an enhanced ability to withstand shocks and stressors of various kinds, i.e., it renders these systems less vulnerable. Consequently, the findings of this study assume significant importance in view of all challenges faced by Greek (and more generally the Mediterranean) agriculture, especially climate change, economic crises, and other stressors. Furthermore, the sustainability performance variation of the farming systems under consideration can be investigated in the light of future changes, such as climate change. In particular, foresight scenarios can be used for crop yields and prices based on the Fifth Intergovernmental Panel on Climate Change (IPCC) report, which takes into account the possible global climate and socio-economic changes. We should not forget that the dual entity farm firm/farm household is a system that is part of a broader hierarchy of agriculture-related systems. Therefore, a systemic approach is needed, whereby sustainability is seen as an emergent property, related to particular levels within the hierarchy. As Webster [
62] rightly points out, “its operational definition at the farm level thus may not apply at other levels in the hierarchy.”
The proposed methodology has enabled us to identify both intra- and inter-agricultural system heterogeneity with regard to the sustainability performance of different farms across the sub-criteria in each of the three dimensions (pillars). In the social dimension, this variation is more pronounced. Nevertheless, the picture is much clearer when the overall sustainability assessment is conducted. Interestingly, it seems that three “typical” Mediterranean farming systems, as practiced by professional farms in Greece (permanent crops, olive trees, and sheep), are more sustainable than arable crops. In the case of professional sheep farms, the high sustainability performance confirms previous findings in the literature [
63,
64]. This study could support the role of specific agricultural sectors and consequently farmers through compensating them according to their significant contribution to more sustainable farming practices. Given the multi-dimensional nature of any sustainability assessment, some room should be given for flexibility in the use of sustainability performance indicators.
As we have seen, the relative ranking of the examined farming systems seems to be consistent across four different policy priorities. This finding implies that even under diverse prioritization concerning the three pillars of sustainability, permanent crops, olive trees, and sheep will be expected to outperform arable crops. Hence, the proposed varied prioritization of the three pillars can aid policymakers to have a clear picture of the expected sustainability performance of each farming system.
In addition, this analysis can support policy advice and improve the applied institutional framework under the new CAP (2021–2027), where the pursuit of a sustainable agricultural sector is much more explicit than before, through three general and nine specific objectives [
65]. The proposed methodology can support a more ‘holistic’ approach to the new architecture of the CAP, i.e., a view that can transcend the individual specific objectives of the new CAP. In addition, mandatory sector-specific interventions are envisaged in the CAP strategic plan to be developed by each country. More concretely, a thorough justification will be required for the choice of the sectors to be targeted, as well as for the various interventions which will be specific to each of these sectors. Additional requirements for sectoral and spatial specifications are foreseen for both the nine specific objectives of the new CAP and the needs, which after their identification, will have to be prioritized and ranked.
In this context, the findings of this study could prove very useful. For example, three out of four economic indicators we have used in our study are directly related to all impact indicators of the first specific objective of the new CAP; similar matches exist for some of our social and environmental indicators (see
Appendix A Table A3 for details). Likewise, the other economic indicator we have used (total output/total input) is related to total factor productivity (TFP), which is a ‘context indicator’ proposed for the assessment of the second specific objective of the new CAP. Also, TFP can be improved with new investments, whose effectiveness can be enhanced through better targeting and design. Our analysis can support such an endeavour. Indicatively, the following investment priorities for the sectors considered may be mentioned: (a) the adoption and planting of new citrus varieties, i.e., a reorganization of the system through new investments, for opening new export markets; (b) investments for the promotion of the specific identities of various extra virgin olive oils, based on the valuation of positive externalities provided by this system; (c) collective action initiatives, including investments, for the substantiation of the unique identity of dairy products produced by sheep milk, such as ‘feta’ cheese, which has been a designated geographical indication status.
Finally, we have to highlight that this pilot research indicates some limitations due to the small sample size and the use of one-year data. The sample of farmers may have a selection bias as it was not a real random one. Furthermore, in some cases, the variables may have been influenced by specific conditions such as weather that affect either yield conditions or price fluctuations for the referring year. Other limitations may be referred to, including either missing data or incomplete information from the farmers’ side, as a few of them record their data. Available data for all farm types and more years will support the learning effects to better explain the factors that contribute to the sustainability and elucidate the cause–effort relationships for better decision management at the farm and institutional level.
5. Conclusions
The objective of this paper was to conduct a comparative assessment of the sustainability performance of four typical farming systems in Greece using an AHP method to aggregate sets of economic, social, and environmental sustainability indicators. The preceding analysis has yielded some interesting results, from both a methodological and an empirical point of view.
Despite the large amount of data needed, the concurrent consideration of all pillars of sustainability through AHP at the farm level, based on an enriched database of FADN, can provide a meaningful set of indicators that enable a thorough sustainability assessment. By applying the proposed methodology, we have identified significant intra- and inter-agricultural system heterogeneity in regard to the sustainability performance of different farms, as well as a clear ranking of the relative performance of the examined systems. At least two of the studied farming systems were found to be both extensive and sustainable in economic, social, and environmental terms. In addition, three “typical” Mediterranean farming systems, as practiced by professional farms in Greece (permanent crops, olive trees, and sheep), were observed to be more sustainable than arable crops.
Far from being “neutral” or “objective”, composite indicators for each of the pillars of sustainability facilitate the relative ranking of the examined systems. Moreover, the proposed methodology enables the inclusion of sustainability assessment into policy formation by assigning the three pillars of sustainability different weights. We have seen that the relative ranking holds under some possible varied priorities of policymakers. Future research efforts could focus on developing approaches to assess the sustainability performance to provide insights for recommendations and improvement for the long-term sustainability of farms.