**5. General conclusions**

This work aimed to illustrate how GIS-based models can be used as tools for environmental studies through three case studies in the south of mainland Portugal. The first dealt with the problem of geo-form classification in the Ria Formosa estuary. The second focused on using DEM/DTM-based climate models to obtain and analyze isohyetal maps and to identify rainfall distribution influence on water erosion at the Serra de Grândola. In the third application, GIS-based models were used to determine hydrological regional parameters for urban flood mapping purposes (this last application focused in the Séqua/Gilão River and the city of Tavira). The applications allowed demonstrating the versatility and usefulness of GIS-based models when used to solve environmental issues.

### **Author details**

Jorge M. G. P. Isidoro *IMAR – Marine and Environmental Research Centre, Department of Civil Engineering, University of Algarve, Campus da Penha, Faro, Portugal* 

Helena M. N. P. V. Fernandez and Fernando M. G. Martins *Department of Civil Engineering, University of Algarve, Campus da Penha, Faro, Portugal*  GIS-Based Models as Tools for Environmental Issues: Applications in the South of Portugal 273

Cerdan O, Govers G, Le Bissonais Y, Van Oost K, Poesen J, Saby N, Gobin A, Vacca A, Quinton J, Auerswald K, Klik A, Kwaad F, Raclot D, Ionita I, Rejman J, Rousseva S, Muxart T, Roxo MJ, Dostal T. (2012). Rates and spatial variations of soil erosion in

Europe: A study based on erosion plot data. *Geomorphology,* 122(1-2), pp. 167-177. CORINE-CEC (1992). *CORINE soil erosion risk and important land resources. An assessment to evaluate and map the distribution of land quality and soil erosion risk*. Office for official

CORINE-CLC (2006). *Cartografia CORINE Land Cover 2006 para Portugal Continental*. Instituto

DGM (1984). *Carta Geológica à escala 1:50,000*. Direcção-Geral de Minas e Serviços Geológicos.

de Lima JLMP (2010) (ed.). *Hidrologia Urbana: Conceitos Básicos*. ERSAR - Entidade

Díez-Herrero A, Gómez JL, Pérez IG, Azcárate JA, Moral SS, Jiménez JCC (2006). Análisis de la insolación directa potencial como factor de degradación de los conjuntos pictóricos rupestres de Villar del Humo (cuenca). *Proceedings of the IX Reunión Nacional de Geomorfología: Geomorfología y territorio*, Santiago de Compostela, 13-15 September 2006,

Dikau R (1989). The application of a digital relief model to landform analysis in geomorphology, In: Raper J, ed. *Three dimensional applications in Geographical Information* 

Dikau R, Brabb EE, Mark R (1991). *Landform classification of New Mexico by computer*. US

Drãgut L, Blaschke T (2006). Automated Classification of Landform Elements Using Object-

Eswaran H, Reich P, Beinroth F (2001). Global desertification tension zones, In: Stott DE, Mohtar RH, Steinhardt GC, eds. 2001. *Sustaining the global farm. Selected papers from the 10th International Soil Conservation Organization Meeting*, 24-29 May 1999, Purdue, pp. 24-

FAO (1989). Role of forestry in combating desertification. *FAO Conservation Guide No. 21,* Forest Conservation and Wildlands Branch, Forest Resources Division, Forestry

Favis-Mortlock DT, Guerra AJT (1999). The implications of general circulation model estimate of rainfall for future erosion: A case study from Brazil. *Catena*, 37, pp. 329-354. Favis-Mortlock DT, Savabi MR (1996). Shifts in rates and spatial distributions of soil erosion and deposition under climate changes, In: Anderson MG, Brooks SM, eds. *Advances in* 

Felicísimo AM (1999). La utilización de los MDT en los estudios del medio físico. *150 aniversario de la creación del Instituto Tecnológico Geominero de España*, Universidad de

Geográfico do Exército, Grupo de Detecção Remota, Lisbon (in Portuguese).

Chow VT, Mays L, Maidment D (1988). *Applied Hydrology,* New York, McGraw-Hill.

Reguladora de Serviços de Água e Resíduos, Lisbon (in Portuguese).

publications of the European Communities, City of Luxemburg.

Chow VT (1959). *Open Channel Hydraulics*, New York, McGraw-Hill.

Lisboa.

28.

Department, Rome.

pp. 903-1008 (in Spanish).

*Systems*, Taylor & Francis, London, pp. 51-77.

Geological Survey, Open File Report 91/634.

*Hillslope Processes*, Vol. 1, Chichester, Wiley.

Oviedo, Oviedo (in Spanish).

Based Image Analysis. *Geomorphology*, 81(3-4), pp. 330-344. Eastman JR (2009). IDRISI Taiga, Worcester, Clark University.

João L. M. P. de Lima *IMAR – Marine and Environmental Research Centre, Department of Civil Engineering, University of Coimbra, Rua Luís Reis Santos, Campus II – University of Coimbra, Coimbra, Portugal* 
