Emission of Pollution to the Environment Using as Substrates Almond Shell and Rockwool in Soilless Culture

The majority of the horticulture production systems in soilless culture are open systems in which the nutritive solution of leaching is thrown away on soil, and it is pollute. Several authors point out that the use of organic substrates as culture media, reduce considerably the emission of nitrates and phosphates on soil, in comparison to the inorganic substrates. For this reason, during the years 2001 to 2003, it was determined at the University of Almeria, Spain, the effect of the substrates almond shell and rock-wool in the incorporation of ions to the substrate-plant system, as well as the emission of pollution and soilless. For this, it was used as witness culture melon and tomato plants, both were evaluated in two experiments. The results showed that in the eight elements determinated, there were no significant differences between substrates for the incorporation of ions to the substrate-plant system except the potassium, which in the rock-wool substrate included more of 15% ions to the system than the almond shell. In the emission of nitrates and phosphates on soil as the main pollution, there were significant differences between substrates, in melon and tomato in which the use of almond shell reduced in a 50% the emission to the environment in comparison to the rock-wool. It was concluded that the environmental pollution will be a very important reason for decide the utilization of almond shell as a vegetable soilless culture media in comparison to the rockwool.