Alpeorujo’s compost improves the properties of low-rainfall saline land

Spanish researchers have proved that the combined use of the compost of the waste obtained from olive grinding (alpeorujo) and manure improve agricultural land properties with a high salt content.

The improvement is especially interesting for those soils irrigated with poor quality water in low-rainfall areas, such as the Mediterranean coast.

Researchers of the Centre of Pedology and Applied Biology of Segura (CSIC, Murcia – Spain) have confirmed that the use of compost of alpeorujo, the waste obtained from grinded olives, and manure, improve the properties of agricultural land with a high salt content. This fact is a consequence of the poor quality of irrigation water in low-rainfall areas, like those of the Mediterranean ecosystems.

The work has revealed that the use of organic matter in saline soils prevents the entry of sodium in the soil change complex, at the same time that the organic emendations “improve the ionic balance of the plants, boosting their development and production”, as CSIC researcher María del Pilar Bernal Calderón has informed Oleociencia (www.oleociencia.es). To this respect, the study has showed the double benefit of the application of organic compost: On the one hand, enriching and recovering land and, on the other hand, re-establishing the ionic balance, which gives rise to an improvement of plants’ mineral nutrition.

Likewise, Bernal has emphasized the importance of the selection of the vegetable species grown in land with a high saline content. In the study, the species which show a better tolerance to salinity, such as Swiss chard and cabbage, “respond clearly to the treatment with organic matter and, therefore, their cultivation is more recommendable than other species less tolerant to salts, such as tomato”, he asserts.

Applied research work

The research work, titled “Bioremediation with detox plants of saline and metal-polluted soils”, has been led by CSIC scientists María del Pilar Bernal and David J. Walter.

The research work has an immediate practical application as it has established the benefits of the use of organic matter in agricultural land with salinity problems, providing scientific reasons for soil and plants improvement.

On the other hand, this research has set the standard for the conservation of the natural resources through sustainable organic waste recycling and the recovery of polluted soils. These soils are usually located in low-rainfall areas, a fact that, combined with high evapotranspiration rates due to the high temperatures, gives rise to an important water shortage.

The results of Bernal and Walter’s research works have been published by scientific journals such as the Journal of Environmental Quality, Environmental Pollution, Ecosistemas, Ecotoxicology and Envionmental Safety, Chemosphere o Water & Pollution.