| Apart from being competitive, agriculture must comply with the requirements of multifunctionality, food safety and sustainability, as a reduction in aid is foreseen.;Therefore, the new century coincides with a drastic need to introduce new orientations in the fruit and vegetable sector. Farmers must plan their activities regardless of subventions. However, now, to the traditional economic objectives that motivated the decisions of farmers, we must add others of a social and environmental nature that are equally important.;The objective of the present doctoral thesis is to establish the degree of viability and competitiveness of three very significant farming systems in the Mediterranean area, taking into account agronomic, technical and socio-economic aspects.;The production systems selected to represent Valencian agriculture are: an irrigation system located on the North-South plain, that includes the cultivation of citrus products and vegetables in the open air; an unirrigated system that represents the inland areas where farming is based on vines, olives and almonds; a third system, which is very closed and characteristic, has also been included, located in the bagged grape growing area of Vinalopo (Alicante).;The main methodology selected has been a Mathematical Programming system. For the Vinalopo farming system, a classic Linear Programming has been applied while for the unirrigated-woody system a Multi-objective Programming has been used as well as a Compromise Programming, both belonging to the multi-criteria paradigm. Finally, for the irrigation system, a multi-criteria technique was used called the Multi-attribute Utility Function.;Four types of farm have been considered for the Vinalopo and unirrigated systems, and one management unit associated to the irrigation system, which represents the future orientation of Valencian agricultural farms.;For each farming system, different scenarios concerning the adoption of technology have been proposed. The analysis of multiple objectives has provided solutions for each system on farm viability or management unit, effects of intensification and economic, social and environmental effects of the level of use of production factors. |
