Enhancing diversification of cropping systems to minimize agri-environmental problems: Results of stakeholders' consultation in Italy

1 Introduction Since the late 1950s, the advances in agronomy, genetics, and chemistry significantly increased crop yields worldwide. However, the strong simplification and intensification of conventional farming systems, through a growing use of chemical inputs, water, fossil fuel energy, and agrochemical products (fertilizers, pesticides), have caused significant environmental impacts (Wezel et al., 2018). These impacts include groundwater pollution, greenhouse gas emissions, soil erosion, loss of biodiversity, and reduction of agroecosystem services – such as loss of soil fertility and soil degradation. Collectively, these impacts have implications for long-term farming system sustainability and environmental quality. Therefore, the adoption of crop diversification strategies (e.g. rotation, intercropping, and multiple cropping) and alternative management practices (e.g. reducing tillage intensity, organic and mixed fertilization, crop residue management, and optimizing water use efficiency for irrigated systems) allows to achieve sustainable systems and food production with lower inputs, and minimizing the environmental and social impacts of agricultural practices without compromising crop yields and incomes. In this context, the five-year Horizon 2020 Diverfarming project (www.diverfarming.eu) aims to define sustainable, diversified cropping systems with low-input farming practices, adopting a multi-disciplinary approach across Europe. In the Mediterranean Basin, arable agricultural systems are highly specialized and characterized by a few improved high-yielding species, mostly oriented on cereal-based intensive cropping systems under rainfed or irrigated conditions as monoculture, or short rotations such as wheat-summer irrigated crops, or mixed succession with bare fallow (Di Bene et al., 2016; Francaviglia and Di Bene, 2019). The region is extremely vulnerable to environmental or anthropogenic pressures and increasing the diversification of cropping systems can stabilize agroecosystem productivity more than conventional agriculture (monoculture, intensive tillage, and higher external inputs), enhancing resilience to environmental stress. To achieve this, more attention should be given to the specific local knowledge of soil and land management, involving local stakeholders from the beginning of research activities with participatory methods (Bampa et al., 2019). Therefore, this study directly engaged stakeholders by public consultations to capture their practical knowledge of current farmer practices for promoting suitable diversified cropping system in Italy. In particular, both rainfed-cereal and irrigated-cereal cropping systems were addressed. The consultations also aimed to investigate the interest of stakeholders on potential crop associations and alternative low-input farming strategies for decreasing external inputs and minimizing agri-environmental and socioeconomic problems. 2 Materials and Methods The consultation was based on a questionnaire organized in five parts: 1) general interview information; 2) identification and assessment of the most relevant agri-environmental problems in the study area; 3) selection of measures to tackle the identified problems; 4) selection of diversification alternatives; and 5) management strategies to reduce the impact of conventional cropping systems. The questionnaire, developed by the University of Cartagena (Spain), was implemented online and designed to be easily compiled using laptop, tablet or smartphone. Between 20 and 30 representative stakeholders were intended to be consulted with the following distribution: 1) farmers and technical agricultural advisors (n=12-15); 2) field technical officers from public agricultural administrations (n=3-5); 3) technical experts from NGOs with experience on farming practices (n=2-5); and 4) researchers in agriculture (n=3-5). With the involvement of Italian farmers associations, agricultural cooperatives, and companies a total of 50 stakeholders were selected and directly invited to fill the questionnaire. 3 Results The main outcomes were grouped by rainfed-cereal and irrigated-cereal cropping systems. We got 40 completed questionnaires: 1) farmers and technical agricultural advisors (n=25); 2) field technical officers from public agricultural administrations (n=7); 3) technical experts from NGOs with experience on farming practices (n=1); and 4) researchers in agriculture (n=7). The answers were downloaded in an Excel format template for validation and analysis. In the rainfed-cereal systems, crop rotation, intercropping and multi-cropping were proposed as management alternatives, with crop rotation reaching 85% of the preferences. Faba bean, alfalfa and mixed legumescereals cropping systems were identified as the most feasible crop diversification strategy, accounting for 78% of preferences. In rainfed systems, organic matter inputs, conservation tillage (no-tillage and reduced tillage) and cover crops were preferred as soil conservation and weed management strategies, while integrated management was preferred for pest control. In the irrigated-cereal systems, crop rotation, intercropping and multi-cropping were proposed as management alternatives, with crop rotation reaching 67% of the preferences. In these systems, limited irrigation strategies are frequently adopted in horticultural crops (e.g. tomato). Moreover, precision agriculture was indicated to optimize fertilization, while organic matter inputs, cover crops, and conservation tillage were chosen as soil conservation and weed management strategies. 4 Discussion and Conclusions The results presented allowed to identify relevant strengths and drawbacks for the implementation of diversified cropping systems under low-input agricultural practices. A major strength is that the crop alternatives selected for the diversification are already cultivated as monocultures and are adapted to the local pedoclimatic conditions. So, farmers just need to learn how to use them in combination as rotations, multiple cropping or intercropping. On the other hand, a major weakness is that few farmers are experts in crop diversification. Thus, providing adequate training for public officers and agricultural technical advisors is crucial for successfully implementing diversified cropping systems among farmers. Additionally, the identified low-input farming practices are easy to implement, are not costly, do not require major investments in new machinery nor great farming skills to learn them. This suggests a further significant potential for their implementation at the technical level