According to some European Institutions (European Environment Agency, Commission of the European Communities), Environmental Impact Assessment (EIA) could be a better tool to assist natural resource protection in the context of land use planning than when used only for assessing specific projects. Environmental assessment of planning instruments allows the comparison of different alternatives and to scope the analysis and evaluation of relevant impacts when developing projects in the alternatives selected. This paper develops a minimum indicator set useful to evaluate natural resources quality at municipality level as a basis for assessing environmental impacts derived from land use planning instruments and from specific projects in the Valencian region, a representative area of the European Mediterranean Region. Using Principal Component Analysis (PCA), a minimum set of 12 indicators which referred to relevant natural resources (air, water, soil and biodiversity) was defined and used to assess the resources quality of different municipalities of the Valencian region, following a value-function based approach. The results obtained were very similar to those obtained in another study done in the same area that applied a broader set of indicators. These results and the potential reduction in costs estimated show the usefulness of the minimum set of indicators defined in this work for evaluating resources quality. As a demonstration exercise, the indicator set was applied to three municipalities representative of the different land use conflicts and environmental problems of the Valencian region, in order to assess the environmental impacts on natural resources that could be produced from the implementation of a hypothetic urban-industrial expansion plan, a usual land use pattern that has occurred in the European Mediterranean Region in the lasts decades. The results obtained show that coastal municipalities are better alternatives to implement an urban-industrial expansion than inland and intermediate municipalities in terms of environmental impacts although the loss of high productivity soils must be avoided. Given that the environmental issues considered are representative of the European Mediterranean Region, it follows that the approach developed in this work can be useful to predict environmental impacts on natural resources from planning instruments in the whole region. [ABSTRACT FROM AUTHOR]