A comparison of micronutrients (Mn, Zn, Cu, Mo, Ni, Na) within rocks, soils, and leaves, from fallow agricultural lands and natural laurel forest areas (Tenerife, Canary Islands, Spain)

• We analyzed the micronutrient contents of rocks, soils and leaves.
• Samples originate from fallow agricultural areas and natural laurel forest parts.
• Results were compared with each other and with published geochemical backgrounds.

The laurel forest in Tenerife is an important ecosystem and the habitation of several sensitive and endangered endemic species. Its mountainous areas at the border of the laurel forest vegetation zone, with suitable climatic conditions, have been intensively influenced, over the last decades, by logging and harnessing of agricultural areas. Many areas which were formerly used for agriculture have been abandoned for many decades and can be seen as potential areas for a natural resettlement of laurel forest. In order to classify these fallow areas, total nutrient element contents of rocks, soils and leaves were compared with published geochemical backgrounds, natural laurel forest results and with sufficient nutrient amounts for plant growth. The method determined whether a fallow agricultural sample site contains sufficient, insufficient or excessive micronutrient concentrations. The method indicated that the fallow agricultural sample sites contain Mn, Zn, Cu and Na in the normal range for a sufficient growth of Laurus novocanariensis. Whether agricultural or natural, Mo is mostly below and Ni significantly above the sufficient amount. In any case, the micronutrient results have determined that abandoned agricultural areas near the border of the laurel forest vegetation zone are comparable to the laurel forest and suitable for a resettlement of L. novocanariensis.