Key Factors Shaping Spanish Agriculture
Current Panorama of Spanish Agriculture:
Factors Influencing Farming: Farming is determined by a combination of physical and socioeconomic factors. Physical factors include soil and climate, while socioeconomic factors encompass the active population and land ownership structure.
Physical Factors
Extension of Agricultural Land: Of Spain’s 50.5 million hectares, a breakdown for agricultural purposes includes unproductive land, untilled land, and the Utilized Agricultural Area (UAA). The UAA constitutes 53% of the total land. Discounting land devoted to permanent pasture, the actively worked land represents only 33%. The relatively low soil tilth in Spain is due to several factors, including altitude, erosion, soil quality, and dryness.
- Altitude of Farmland: The optimal altitude for agriculture is between 0 and 200 meters. Only 12% of Spanish soil meets these conditions. In both Castillas, virtually no ground falls within this range.
- Erosion of Farmland: Slope is a major cause of erosion, potentially leading to agricultural land degradation. 12% of Spanish soil has a slope exceeding 5%, the maximum for proper land maintenance and easy mechanization. The area affected by erosion is slightly larger than the UAA.
- Soil Quality: Soil pH is crucial. Soil with acidity below 5 or basicity above 8 is difficult to cultivate. Highly leached silicon soils tend toward acidity, while limestone with low humidity tends toward basicity. In summary, of the 26.3 million hectares making up the UAA, only about 17 million hectares of farmland are suitable for cultivation; the rest is devoted to pastures, wasteland, and fallow pasture.
Climate and Agriculture
- Water Resources: Water resources are very unevenly distributed. From a rainfall perspective, the Iberian Peninsula is divided into wet and dry regions. Dry Iberia represents 77.5% of Spanish land, and its main challenge is not just rainfall shortage but also the irregularity of rainfall. There are frequent periods of low rainfall, precisely during the warmer months. Erratic rainfall can cause harvest loss in a short time. Wet Iberia receives more precipitation, and it is more regular. As 68% of available water is spent on agriculture, there is a great asymmetry between the two Iberias. Numerous dams and canals, such as the Tajo-Segura, have been built to address this.
- Temperature: There is a thermal asymmetry between the interior and the periphery of the Peninsula. The periphery, influenced by the sea, experiences little temperature fluctuation, and the risk of frost is minimal. The interior experiences the opposite: large thermal amplitude, harsh and long winters with hot summers, and a risk of frost that may extend to eight or nine months. Each plant needs a minimum temperature for germination and development; without these temperatures, crop growth is impossible.
- Evapotranspiration: Potential evapotranspiration is highest in summer when water resources are lowest. The difference between rainfall and evapotranspiration is negative in inland Spain. Excessive heat can jeopardize many crops due to lack of water in the soil.
- Aridity: Aridity is the deficit of water for plant and animal life. It is related to both water resources and temperature, being greater in regions of high temperatures.