The Ribera forest in Santa Maria d'Oló

The Oló stream presents a variable flow depending on the time of year, becoming practically dry in some summer moments. Water penetrates the soils on both sides of the stream and underground water is present in the subsoil. The waters carry sediments, which are deposited and give mineral nutrients to the soil. The humidity and the richness of nutrients in the soil are elements that confer productivity and biodiversity in the stream area.

In the space flooded by the stream we find heliophilic, herbaceous communities that have their roots and the base of the stem covered with water, unlike the rest of the plant that is in an aerial position. We also find hydrophilic plants, which can appear both in the flooded space of the stream where the halophytes grow, and in very humid soils not necessarily flooded.

On the banks of the Oló stream we find riparian vegetation that, in some sections, has reached an advanced stage, giving riparian forest. Along some sections, especially in the headwater area, we find the community of the sauceda with sarga, located on the first line of the stream edge, and the alameda with vinca, located on the second line. In some places at the head of the stream the presence of a beautiful protected lily, the red martagon, has been detected .

In the aquatic environment, two native fish are characteristic, the catfish and the red-tailed barbel. At the top of the stream is the presence of some specimen of crayfish, an invertebrate that has been greatly reduced in number of individuals. We also find a great diversity of aquatic insects such as the Elizabethan butterfly or the dragonfly. Among the amphibians, the common toad or the green frog stand out. Some of these amphibians are captured by the water snake and the heron pesacaire. The presence of an otter, a protected mammal in danger of extinction, has also been detected.

Source: Santa Maria de Oló Town Hall