USO DE COPRODUTOS DA EXTRAÇÃO DE VERMICULITA NA PRODUÇÃO DE MUDAS DE FAVELEIRA (Cnidoscolus quercifolius Pohl.).

The extraction of vermiculite generates by-products (BP-vermiculite) that are dumped off in the mine surroundings causing water and visual pollution, and silting up of rivers and reservoirs. These residues have physical and chemical attributes that enable them to replace alluvial soil in the composition of the substrate used to produce tree seedlings.The use of such residues means less environmental pollution, the production of seedlings that can be used for reforestation of degraded areas and the preservation of the sites from which the alluvial soil would be extracted. This paper evaluated the use of the balanced mixture (1:1 v/v) of the fine and ultrafine by-products of the vermiculite extraction as substrate in the production of faveleira (Cnidoscolus quercifolius Pohl.) seedlings and determined the amount of cattle manure necessary to be added to that mixture. The experiment was carried out from April 2013 to February 2014 in a screened shed at the UFCG/CSTRUAEF forest nursery facilities, in Patos, PB - Brazil, according to a completely randomized design with.6 treatments (BP-vermiculite with 0, 5, 10 and 20% cattle manure addition, and alluvial soil with 0 and 33% cattle manure addition) and 5 replications. BP-vermiculite can be used in the production of faveleira seedlings when 10 to 20% manure addition is applied, resulting in seedlings with the same (or higher) height, basal diameter and sprouting vigor observed in seedlings produced with the conventional substrate (alluvial soil and cattle manure). The use of BP-vermiculite to produce favela seedlings is viable, and implies in the reductionof the environmental impacts caused by their deposition in the environment and by the extraction of soil from alluvial sites normally used to produce seedlings. [ABSTRACT FROM AUTHOR]