Avaliação do risco de salinização e sodificação do solo para cultivo de Cannabis sp.

Abstract

Cannabis sp. L. (1753), also called hemp or marijuana, is a genus of the Cannabaceae family, widely used throughout the planet as food, fiber and medicine for at least 12000 years. 104 phytocannabinoids have already been described in the literature as molecules of interest, the main ones being tetrahydrocannabinol (THC), cannabidiol (CBD) and cannabinol (CBN). In view of the application of persecution policies, the culture was becoming scientifically obsolete, but decades followed with persistent results in research and today it is no longer taboo. In Brazil today, ABRACE Esperança works, the first institution in the country authorized by the Justice to cultivate marijuana for medicinal purposes, and it supplies the demand of at least 25 thousand patients who need the medicine. The plant requires minimal agronomic requirements for its development, but there are still few published research papers on nutrient demands. One cause to be investigated as a limiting factor is the process of salinization and/or sodification of the soil in regions under arid and semiarid climate that occurs due to natural causes. The morphological, physical and chemical attributes of a soil and the physical-chemical attributes of the irrigation water in an area authorized for the cultivation of Cannabis sp. were evaluated, with the objective of determining the risk of salinization and/or sodification of the soil and consequently its productivity. The work was carried out in the agricultural production area of ABRACE Esperança, site II “Lucas Alexandre”, in the municipality of Campina Grande. Morphological description of the soil profile, chemical and saturated soil paste analysis, physical analysis and irrigation water were performed. The area's soil is a Natric Planosol, the presence of a Bt (planic) horizon and abrupt textural change cause a very slow percolation of water, with the formation of a suspended sheet. Soils like this present a high risk of salinization and sodification even with the use of better quality water, because the drainage class is imperfect to poorly drained. A management plan for irrigation, fertilization, and mechanical management practices and soil drainage is necessary to improve the arable characteristics for the cultivation of cannabis.