Spanish Vegetation and Flora

Formations

Vegetation and flora encompass the plant species within a vast territory. Floral kingdoms are subdivided into regions. The Iberian Peninsula belongs to the Holarctic kingdom, encompassing landmasses north of the Tropic of Cancer. It features three floral regions:

1. Boreoalpine Region: High-altitude areas of the Pyrenees and Cantabrian Mountains.
2. Eurosiberian Region: Northern Iberian Peninsula, parts of the Central System, and Iberian Mountains.
3. Mediterranean Region: Remaining areas of the Peninsula.

Key factors influencing vegetation include:

Weather

Weather is a crucial determinant of plant development. Xerophytic vegetation thrives in drought conditions, hygrophilous vegetation in wetlands, shade-tolerant vegetation in low-light areas, thermophilic vegetation in warm temperatures, and cryobiontic vegetation in cold climates.

Light

Light influences climate and vegetation. Lower altitudes experience higher temperatures and less rainfall compared to mountains, resulting in distinct vegetation patterns. Mountain slopes also exhibit variations: sunny, south-facing slopes are typically warm and dry, while shady, north-facing slopes are cooler and wetter.

Soil

Soil properties affect vegetation types. Some species prefer siliceous soils, while others thrive in limestone soils.

Human Activities

Human activities have significantly altered vegetation through centuries of forest exploitation, reforestation with non-native species, and land use changes. Wild species develop naturally without human intervention, while endemic species are unique to a specific territory. Spain boasts numerous endemic species, particularly in the Canary Islands and Andalusia. Its diverse vegetation (around 6,000 species) reflects its varied physical features, bridging continental and island environments.

Vegetation is categorized by size and appearance into forests, scrubland, and grassland. These can be climax formations (naturally occurring) or secondary formations (resulting from human activity). Plant communities within a given area constitute its overall vegetation. Climate significantly influences vegetation, leading to the study of plant landscapes based on climatic zones.

Oceanic Climate Vegetation

Deciduous forests in this climate consist of tall trees with smooth, straight trunks and large leaves. Oak and beech are dominant species, while chestnut, ash, linden, elm, hazel, birch, and maple play secondary roles. Ferns thrive in the humid understory.

Beech

Beech tolerates both heat and cold, requiring high humidity. It thrives in mountainous terrain, adapting to calcareous and siliceous soils but preferring the former. Its fast-growing, high-quality hardwood is used for furniture and utensils. Beech forests can be pure or mixed with oak, primarily found in the Cantabrian Mountains and Navarre Pyrenees.

Oak

Oak cannot withstand hot summers, tolerates less cold than beech, and requires less moisture, growing at lower altitudes. Its slow-growing hardwood is used in construction, furniture, and shipbuilding. Oak forests, now reduced in size, are mainly found in Galicia and the Cantabrian Mountains.

The oceanic climate also features marcescent forests with rebollo and gall oaks, smaller trees that retain their leaves until new buds emerge. Over-exploitation and reforestation with fast-growing pines and eucalyptus have significantly reduced deciduous forests. These reforestation efforts have been criticized for soil impoverishment and increased fire risk.

Heath and Grasslands

Heath is dense shrub vegetation dominated by heather, gorse, brambles, boxwood, wild roses, and broom. It appears in degraded deciduous forests or at elevations between 1,600 and 2,000 meters. Grasslands occupy large areas in oceanic regions, providing abundant herbaceous vegetation and pastures.

Mediterranean Climate Vegetation

Evergreen forests and scrubland (maquis, garrigue, and steppe) characterize this climate, adapted to summer drought. Evergreen forests comprise medium-height trees with irregular trunks, thick bark, and globular crowns that shade the ground, reducing evaporation. Holm oak and cork oak are the most characteristic species.

Holm Oak

Holm oak is the most widespread tree in the Mediterranean climate, resistant to drought and adaptable to various soils. Its durable wood and acorns (used for livestock feed) are valuable resources. Well-preserved holm oak forests exist in Sierra Morena, Extremadura, and Sierra de Guadarrama.

Cork Oak

Cork oak requires mild winters, some moisture, and siliceous soils, found in Extremadura, parts of the Guadalquivir depression, and Catalonia. Its bark provides cork.

Pine

Pine is a secondary formation adapted to various conditions and soils. Human activity has expanded its range due to its fast growth and economic value (resin and wood). Its conical shape, needle-like leaves, and sparse undergrowth (due to needle acidity) are distinctive features.

Over-exploitation, fires, and human intervention have reduced evergreen forests. The dehesa system, combining clarified oak and cork oak forests with fruit, wood, agriculture, and grazing, is a common practice.

Mediterranean scrubland results from forest degradation. Three types exist:

1. Maquis: Dense shrubland over two meters tall, composed of species like rockrose, heather, mastic, and broom.
2. Garrigue: Low-lying shrubs and bushes with exposed rock, featuring thyme, rosemary, and lavender.
3. Steppe: Found in semi-arid southeastern Spain, characterized by low grasses and scattered thorny bushes, with species like palmetto, thyme, esparto grass, and asparagus.

Riparian Vegetation

Vegetation along riverbanks adapts to moisture and water retention, forming diverse strips of plants. Key characteristics include humidity adaptation and symmetrical bands. Species include birch, elm, poplar, cottonwood, ash, laurel, wild rose, blackberry, and ivy. Riparian vegetation is declining due to agricultural land use.

Canary Islands Vegetation

The Canary Islands possess rich vegetation. Their proximity to Africa, volcanic origin, and subtropical climate contribute to numerous endemic species, such as the dragon tree. Vegetation is stratified:

• Lower elevations: Desert scrub species like cacti and tabaiba due to dryness.
• Up to 800 meters: Varying temperature and rainfall support dragon trees, juniper, and Canary Island palms.
• 800 to 1,200 meters: Laurel forests thrive due to fog, cooler temperatures, and less sunlight. Ferns occupy ravines, and myrtle and heather appear in degraded laurel forests.
• Up to 2,200 meters: Coniferous forests dominated by Canary Island pine.
• Above 2,200 meters: Sparse broom vegetation due to cold, but rich in endemic species.

Lanzarote and Fuerteventura, with lower elevations, lack high-mountain vegetation due to the trade winds preventing cloud formation.

Mountain Vegetation

Altitude creates vegetation belts, known as cliseries. Precipitation, temperature, and slope orientation influence vegetation changes. Alpine and Pyrenean mountains exhibit the following belts:

1. Subalpine level (1,200-2,400 m): Conifers like fir, black pine, and Scots pine. Fir forests may mix with beech.
2. Alpine level (2,400-3,000 m): Low temperatures prevent tree growth. Alpine meadows, broom, bare rock, and small rock-dwelling plants dominate.
3. Nival level (above 3,000 m): Permanent snow cover prevents vegetation. Small plants like mosses and lichens may appear when snow melts.