Storm Cecilia, Saharan sand and keyline design…
Swales in operation at Joya: AiR
Storm Cecilia, Saharan sand and keyline design… A swale is a ditch built on a contour line. A contour line is a line of equal elevation above sea level. The swale is constructed across a slope and the spoil creates a berm or retaining bank. When it rains, as it just did significantly in this region, the water runs down the slope and is collected in the swale, as you can see in this image. In dry Mediterranean Steppe land like this retaining moisture in the headwaters is an essential design element for restoration agriculture. Rainwater hydrates the clay earth, encouraging plant life who’s roots dig deep below the surface introducing organic matter to the soil. Annuals and perennials grow on this resource, dropping dead leaves year on year creating, spongy, absorbent soils. This creates green growth, improves the soil, draws down carbon, stores water. Shade cools the surface and creates a microclimate.
Storm Cecila brought us this inundation in the form of ‘lluvia de barro’ or mud rain. Sand blown from the Saharan desert was deposited in great sweeps of red and momentarily we became like Mars. The ‘lluvia de barro’ is beneficial as it spreads naturally occurring mineral fertilizer across soils which, in this region, are poor. Now we wait for the sun and the explosion of wildflowers.
