The Central Plain of Mallorca called "Es Pla" is an extensive area located between Tramuntana Range and Llevant Range. We can find several geomorphology domains in the Central Plain: on one hand the plains of Palma, Inca-Sa Pobla, and Campos-Manacor, and on the other hand the low and central relieves with an altitude always minor of 300 meters.

Relieve, climate and soils have conditioned the agricultural settlement. The Central Plain constitutes an agricultural landscape, which is the result of the transformation of natural environment. This agricultural landscape is mainly concentrated in the soils more productive and fertile of the island.

Dry lands represent the main crop of Mallorca. The average surface of properties is of 4 hectares. Walls of dry stones often close these properties. These lands are dedicated to a crop system with herbaceous and woody species. The Mediterranean trilogy: cereals, olive trees and vineyards fit perfectly to physical characteristics of the island. Other important crops are fig trees (Ficus carica), carob trees (Ceratonia siliqua) and almond trees (Prunus dulcis).

Irrigated lands represent a minor extension, although their economic weight is quite important. Irrigated lands are basically concentrated in three irrigated traditional regions: the plain of Sa Pobla-Muro (at the North-East), Campos (at the South) and the plain of Sant Jordi (at the west). The crops more important for their extension are forages. Their existence is connected to the cattle raising and it is mainly concentrated in the area of Campos. Vegetables and tubercles are the second important crops and are concentrated in the plain of Sa Pobla-Muro and, in minor quantity, in the plain of Sant Jordi.

Since ancient times agriculture has been the economical and food base of the population of the island. More than fifty per cent of the population of the island worked in the agricultural sector.

From the sixties, with the mass tourism, there was a progressive migration of labour from primary to tertiary sector, from agriculture to the tourist sector. This economic change in the objects of labour mainly among the rural population led to a profound change in the use of agricultural land. The first change on the land surface was the recession of the cultivated lands due to the increase of the building-up area for tourist and urban activities. On the other hand there was a process of recession of the dry extensive agriculture with an increase of irrigated intensive agriculture, which grows as answer to the urban and tourist demand.

In the nineties, the disappearance of agriculture activities is a fact, the only alternative is the hobby agriculture. Nowadays, in some rural areas, there is an increase of the residential use for local people and also for foreigners. Also, in the last years, there is a new process of tourist development, another kind of tourism as alternative of the mass tourism: the rural tourism and the agro-tourism. All those reasons have changed the traditional agricultural landscape.

While unirrigated crops are in a process of slump and degradation, the situation on irrigated crops is quite different. There are some rural traditional spaces in the interior of the island in a subsistence situation. These spaces are in a North-South corridor at the east of Mallorca, from the plain of Sa Pobla-Muro to the plain of Campos. In these spaces the agriculture has experienced a process of modernisation, mechanisation and intensification. However, this process has generated some environmental impacts.

One of the most important impacts of the intensive agriculture is the high demand of water. Irrigated crops are the mean consumers of water in Mallorca with a 65 per cent of the global hydrological consumption. Thus, in traditional irrigated areas as the plain of Sant Jordi and Campos, the practice of the irrigation has high consumption because of high salt contents in the water. This produces an overexploitation of aquifers and phenomenons of sea intrusion. Another environmental impact is produced by the use of fertilizers and insecticides. This kind of contamination is very important in the plain of Sant Jordi, in the plain of Campos and mainly in the plain of Sa Pobla-Muro because these contaminants substances infiltrate into the subsoil and affect to the Natural Park of S’Albufera.

Bibliography.

AAVV (1989-1998). Gran Enciclopèdia de Mallorca. Promomallorca S.A.Inca. Spain.

BINIMELIS SEBASTIÁN, J (1993): "La urbanització del camp". In Geografia General dels Països Catalans. Gran Enciclopèdia Catalana., VI. Barcelona. Spain.

PICORNELL.C.; SEGUÍ, J. M. (1989): Geografía humana de las Islas Baleares. Oikos-Tau. Barcelona. Spain.

SALVÀ TOMÀS, P (1987). "Els efectes del turisme en els sector econòmics". In Llibre Blanc del Turisme a les Illes Balears. Universitat de les Illes Balears. Conselleria de Turisme (Govern Balear) - Sa Nostra. Palma. Spain.

SALVÀ TOMÀS, P. (1985): "La estructura agraria de las Islas Baleares", El Campo, 100. Pag.19-27. Banco de Bilbao. Bilbao, Spain.