1. International Conference of Agricultural Engineering XXXVII Congresso Brasileiro de Engenharia Agrícola ASABE ILES VIII Iguassu Falls City – Brazil – August 31 to September 04, 2008 VALTER BEZERRA DANTAS 1, RICARDO H. HERNÁNDEZ 2, JOAQUIM ODILON PEREIRA 3, IRDES MARIA SARTURI 4, DINARA SIMÃO DE ARAUJO 3 BEHAVIOUR PHYSIC OF A RED LATOSSOLO DISTROFÉRRICO ON DIFFERENT RATIO OF APPLICATION OF STRAW OAT 2Undergraduate student, UNIOESTE/Cascavel – PR.- Brazil e-mail: rhhe@utfpr.edu.br 4 Student graduate DQ/UNIOESTE/Toledo - PR – Brazil. 1 Prof M.Sc. DCA/UFERSA/Mossoró RN – Brazil. e-mail: valter.fisic@hotmail.com 3 Prof. Dr. DCA/UFERSA/Mossoró- RN – Brazil e-mail: jodilon@ufersa.edu.br 5 Student of Agricultural Engineering and Environmental DCA/UFERSA/Mossoró – Brazil. ABSTRACT: The physical, chemistry and biological degradation of soil increase by the intensive use of tractors and agricultural implements, associated with exposure of the soil to the weather, as well as, sunstroke and the impact of the rain drops, This study had the objective of evaluating the effect of the application of four dosages of oat straw (Avena sativa) on the soil, in the proportion of 2, 3, 4 and 6 t/ha.The soil submitted to the study is classified like Latossolo Vermelho distroferric, plane relief and of loamy texture. The experiment was accomplished in the period of August 19 from 2005 to 15 of November 2006 and is located in the Experimenta Nucleus of Agricultural Engineering (NEEA), belonging to the State University of the West of Paraná, UNIOESTE. The sampling places were chosen to obtain the contrasting effect among the straw oats dosages and of the structural and organic state of the soil. They were appraised the organic matter content, the density of particles, the density of the soil and the total porosity. The obtained data demonstrate the increase of the density of particles and the soil porosity in the portions with larger application tax of oats straw. KEYWORDS: oats straw, organic matter, total porosity However, regarding the plots T3 and T4 an increase took place significantly, proving the effect of the organic matter content in the biggest taxes of application of straw in the soil. Table 1. Organic matter content (g.cm-3) for the plots and witness in function of the depth. Legend T1 = treatment without straw addition = T2 treatment with 2 kg/m 2 of maize straw = T3 treatment with 3 kg/m 2 of maize straw = T4 treatment with 6kg/m2 of Straw of maize =T5 treatment with 8 kg/m 2 of maize straw. Figure 2. Effect of quantity of straw in the particle density in function of the depth. The plots (T3 and T4) with bigger quantity of straw incorporated to the soil presented increased in the total porosity, principally, in the superficial layer of the soil, when a decrease is taking place with the depth (Figure 3). Such results can have been favored by the reduction of the superficial drainage, of the increase of the respiratory metabolism and of other biochemical parallel processes, reduction of the temperature of the soil, in the reserve of nutritious ones in compounds vegetables moulds in the action of the nutritious ones immobilized in the metabolic vital cycles of the micro and macrobiotic of the soil and in the action of the nutritious ones immobilized in the metabolic vital cycles of the micro and macrobiotic of the soil. RESULTS AND DISCUSSION: In the Table 1 presented the middle values of organic matter content in all plot and in the witness. The results indicate that small difference took place between the plots T1 and T2 regarding witness. METHODOLOGY: The experiment was carried out from 19 of August of 2005 to 15 of November 2006 in the Experimental Nucleus of Agricultural Engineering (NEEA), of the State University West Parana - UNIOESTE, Cascavel - PR - Brazil, (24°54S and 53°31W.), altitude of 760 m. The soil is classified like Latossolo Vermelho distroférrico with flat relief and of clay texture. The climate is seasoned mesotérmico and super wet according to classification of Köppen. The middle temperature is 21 ºC with middle annual haste of 1.940mm and relative moisture of the annual air of 75 %mThe treatments were constituted by five pieces, including the witness, measuring 2m x 1m, isolatedwith wooden planks; four plots had applications of straw oat in the reasons of 2,0 t/ha; 3,0 t/ha; 4,0 t/ha and 6,0 t/ha, constituting the plots T1, T2, T3 and T4, respectively and one withoutapplication.%. After 453 days of application of the straw the collects of soil were carried out, in three depths (0-5 cm, 5-10 cm and 10-20 cm), with rings of 24 mm of height by 74 mm of diameter when four repetitions are used for depth and for treatment for determination of the bulk density (ρs). Samples of soil were collected to determiner particle density (ρp) and organic matter content. The organic matter was determined at laboratories of the Companhia de Desenvovimento Tecnológico de Cascavel (CODETEC), following the methodology of Walkey Black (KIEHL, 1979). The particle density was measured using a method of pycnometer with water on four replicates per plot. The total porosity was calculated by Pt =1- (ρs/ρp) (1) where ρs is the bulk density and ρp the particle density.The obtained data were tabulated in electronic spreadsheet (Excel), when printers made from the averages of the plots with the organic matter, density of particles and total porosity (Pt) in function of the depth. INTRODUCTION: The soil microbiota - great number of small lively beings as ants, beetles, larvae, slugs, snails, worms, funguses and seaweeds - acts in the formation and in the aggregates stability and in the ciclagem of nutritious ones, being an indicator of the quality of the ground, being fed of the organic matter originating from the remains of cultures or remains of animals. The incidence of rays of the sun on the ground without covering increasing to temperature of his surface in more than 50 ºC causes destructions of the microorganisms (MAZUCHOWSKI & DERPSCH, 1995). In the State of the Paraná the intensive mechanization and his preparation in unsuitable conditions, has been altering his physical characteristics in variable degrees. The principal alterations are shown up by modifications in the values of bulk density, total porosity, distribution of the diameter of the pores and structural porosity, storage and availability of water to the plants, aggregation and organic matter (LEITE, 1996; KLEIN et al., 1998; LONGO, 1999; MELLO IVO et al. 1999). This study had the objective to value the effect of the application of straw of oat incorporated to the ground at the reasons of 2,0 t/ha plot (T1), 3,0 t/ha plot (T2), 4,0 t/ha plot (T3) and 6,0 t/ha plot (T4), at the structural state and organic of the soil. CONCLUSION: The biggest quantity of application of straw of oat promote the reduction of the density, increase of the total porosity, which are indicative of improvement in the physical and chemical properties of the soil. REFERENCES: MAZUCHOWSKI,J.Z; DERPSCH, R. Guia de preparo do solo para culturas anuais mecanizadas.Curitiba, Acarpa, 68p 1995 LEITE, J.A. Influência dos sistemas de manejo sobre os atributos físicos e físico-hídricos de um Latossolo Amarelo (Typic Haplortox). 37 f. Tese de Livre- Docência em Manejo e Conservação do Solo e da Água, Universidade do Amazonas, Manaus. 1996. KLEIN, V.A.; LIBARDI, P.L.; SILVA, A.P. Resistência mecânica do solo à penetração sob diferentes condições de densidade e teor de água. Engenharia Agrícola, Jaboticabal, v.18, n.2, p.45-54. 1998. LONGO, R.M. Modificações em parâmetros físicos e químicos de Latossolos argilosos decorrentes da substituição da Floresta Amazônica e do Cerrado por pastagens. 102 f. Tese de Doutorado, Curso de Pós-Graduação em Engenharia Agrícola, Universidade Estadual de Campinas, Campinas. 1999. MELLO IVO, W.M.P.; MIELNICZUK, J. Influência da estrutura do solo na distribuição e na morfologia do sistema radicular do milho sob três métodos de preparo. Revista Brasileira de Ciência do Solo, Viçosa, v.23, n.1, p.135-14. 1999. KIEHL, E. J. Manual de edafologia: relações solo planta. 22. ed. Piracicaba: Agronômica Ceres Ltda., cap. 1, 264 p. 1979 Particle of added Hypothetically with minerals and organic substance The conditions physical of the ground and improved with increment of oats straws MINISTÉRIO DA EDUCAÇÃO UNIVERSIDADE FEDERAL RURAL DO SEMI- ÁRIDO