Soil sampling: Dona Morta Dalt

Soil sampling: Dona Morta Dalt

The soil in this garden that lies on a ridge in the middle of a light forest is very shallow and shows a depth of around 44 cm. It is covered with plant and tree debris like leaves, pine needles and small parts of dead wood. The O-horizon has a thickness of around 2 cm. The characterization of the other soil horizons seemed to be more difficult. The A-horizon has a depth of around 25 cm, followed by a B-horizon of 20 cm.

Soil profile of Dona Morta Dalt © Chair of Being Alive, 2022.

Overall, the soil color ranges from very dark brown on the upper part of the profile to brown in the lower parts. There are large flecks of white in the C-horizon close to the bedrock. The soil texture reads from silt loam to silty clay from top to down.

Comparing these results with the data from the soil literature, the soil at Dona Morta Dalt is best characterized as a “Morull” soil. Morull type soils are shallow, well drained and of medium texture, with some coarse ele­ments. The main difference to the description is that the soil at the garden has a much higher content of organic matter. This might be due to the fact that the plot lies in a forest. Over time, organic matter accumulated in the soil.

In addition to the soil profile made by the team, a local soil scientist did a lab analysis. For this, 100 grams of the soil sample was taken from the A-horizon in a depth of 10 cm.

The analytical results indicate that the soil is basic, with very high calcareous levels, not saline, with a low content of nitrogen and phosphorus macronutrients and an optimal potassium value. The content of organic matter is very high (10.06%) and presents medium or low levels of micronutrients, except for magnesium and calcium that are high. As for the physical characteristics of the soil, it has a Loam-silt texture.

The analytical results indicate that the soil is basic, with very high calcareous levels, not saline, with a low content of nitrogen and phosphorus macronutrients and an optimal potassium value. The content of organic matter is very high (10.06%) and presents medium or low levels of micronutrients, except for magnesium and calcium that are high. As for the physical characteristics of the soil, it has a Loam-silt texture.

Analytical values of Dona Morta Dalt © Chair of Being Alive, 2021.

As a synthesis of the different soil analysis methods, the team developed a drawing of the soil profile using the soil language of the Chair of Being Alive. This drawing combines quantitative data from laboratory analysis and qualitative data from fieldwork. Following this logic, the data for the A-horizon comes from the laboratory analysis and the data for all other horizons comes from the field methods. Since these two approaches are inherently different, this explains possible inconsistencies in the drawing.

Drawing of the soil profile at Dona Morta Dalt. Source: Chair of Being Alive, 2022.