FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / As tortas resultantes da extraÃÃo do Ãleo das sementes de PinhÃo manso e Mamona constituem-se excelentes fontes de matÃria orgÃnica, ricas em nitrogÃnio, fÃsforo, potÃssio e outros nutrientes. No entanto, o problema està relacionado ao direcionamento dado a esses resÃduos vegetais, quando gerados em grande escala, pois a destinaÃÃo inadequada desses subprodutos pode limitar a eficiÃncia da produÃÃo e a preservaÃÃo do ambiente. Nesse sentido, buscou-se atravÃs deste trabalho, conhecer os efeitos da aplicaÃÃo desses subprodutos no solo de duas Ãreas: uma sobrepastejo e, outra de exclusÃo de sobrepastejo, ambas localizadas na regiÃo de IrauÃuba-CE, sobretudo nos parÃmetros quÃmicos e biolÃgicos que quantificam a qualidade do solo. O experimento foi conduzido em casa de vegetaÃÃo do Departamento de CiÃncias do Solo da Universidade Federal do CearÃ, Campus do Pici, em Fortaleza-CE e analisado, considerando-se cada torta individualmente dentro de cada Ãrea, utilizando-se um delineamento inteiramente casualizado em esquema fatorial 2 x 3 (2 Ãreas e 3 doses de torta), com seis tratamentos e quatro repetiÃÃes, totalizando 24 parcelas experimentais para cada torta, sendo cada parcela constituÃda por um vaso contendo duas plantas. ApÃs 45 dias da incorporaÃÃo das tortas ao solo dos vasos, semeiou-se feijÃo caupi [Vigna unguiculata (L.)] e, ao final de 30 dias de cultivo, foram determinados os valores de pH da soluÃÃo do solo, teores de NPK no solo e na planta, Carbono OrgÃnico Total (COT), densidade de esporos de FMA no solo, Carbono da Biomassa Microbiana (CBM), RespiraÃÃo Basal do Solo (RBS) e os quocientes metabÃlico (qCO2) e microbiano (qMIC). Os resultados demonstraram que a Ãrea sobrepastejo (Ãrea 1) foi a mais favorecida pela aplicaÃÃo das tortas de mamona e pinhÃo manso, especialmente na dose 5% (D2) e a que teve os maiores valores de qCO2, enquanto que a Ãrea de exclusÃo (Ãrea 2) apresentou os maiores valores de CBM do solo. A adiÃÃo das tortas de pinhÃo manso e mamona elevaram os teores de COT e de NPK no solo e nas plantas, indicando que a aplicaÃÃo dessas tortas pode ser uma alternativa na reabilitaÃÃo de Ãreas degradadas. / The residue resulting from the oil extraction of jatropha and castor seeds is considered an excellent source of organic matter, which is rich in nitrogen, phosphorus, potassium and other nutrients. However, the problem is concerned to the fate given to this seed residue, as generated in large scale, since the improper disposal of it may limit the efficiency of production and the environment conservation. In this sense, it was set a research with the objective to evaluate the effects of the application of these seed residues in the soil collected from two areas: an overgrazing site and other conserved as exclusion site, both located in IrauÃuba county of Ceara State, Brazil. The study focused especially on chemical and biological parameters which are related to the soil quality. The experiment was conducted under greenhouse conditions belonging to the Department of Soil Science, Federal University of CearÃ, Campus do Pici, Fortaleza-CE. Plant and soil were analyzed considering each site that received the seed residue. The experimental design was a completely randomized blocks in a 2 x 3 factorial (two areas and three doses of pie), with six treatments and four replicates, totalizing 24 experimental units for each seed residue; each unit consisted of a pot containing two plants. After 45 days of the seed residue application, the pots were sown with cowpea [Vigna unguiculata (L.)] and, after a 30 days growing period, it was determined the pH of the soil solution, the soil and plant NPK contents, Total Organic Carbon (TOC), density of spores in the soil microbial biomass carbon (MBC), soil basal respiration (SBR) and both metabolic (qCO2) and microbial (qMIC) quotients. The results showed that the overgrazing of the area (area 1) was favored by the application of the castor bean and jatropha seed residues, especially at the rate of 5% (D2) which had the highest values of qCO2, while the exclusion area (Ãrea 2) showed the highest values of soil MBC. The addition of jatropha and castor seed residues, at both rates, reduced the density of spores of the soil in both areas, but increased the TOC and NPK soil and plants contents, indicating that the application of these seed residues can be an alternative for rehabilitating degraded soil areas.