RESUMO A fruticultura irrigada no Vale do São Francisco vem se destacando na região Nordeste do Brasil e o manejo incorreto da adubação tem proporcionado problemas de degradação física e/ou química do solo. O trabalho teve como objetivo avaliar a variabilidade espacial dos atributos químicos de um Latossolo Vermelho -Amarelo cultivado com banana (Musa spp). O estudo foi realizado no perímetro irrigado de Nupeba em Riachão das Neves/BA. Em uma área cultivada por 18 anos com banana prata fertirrigada por microaspersão. Em abril de 2017 coletou-se amostras simples de solo nas profundidades de 0-0,20 m e de 0,20-0,40 m, a partir de uma malha experimental constituída de 40 pontos georreferenciados e distanciados a cada 10 metros. Nas amostras de solo foram determinados: pH (H2O); Carbono orgânico; Fósforo (P); Potássio (K+); Cálcio (Ca2+); Magnésio (Mg2+) e Acidez potencial (H+Al) e calculados a soma de bases (SB), capacidade de troca catiônica (CTC) e saturação por bases (V%). Os resultados das análises foram avaliados por meio da estatística descritiva e a técnica da geoestatistica. A análise descritiva identificou a normalidade dos dados. A variabilidade espacial foi confirmada, permitindo a confecção de mapas. A área analisada possui baixa fertilidade (V<55%) e o manejo inadequado de correção e adubação do solo podem reduzir a disponibilidade dos nutrientes para a cultura implantada, tornando o solo passível de degradação com o uso da irrigação. Os mapas de distribuição permitem a visualização da área, possibilitando a aplicação de insumos com taxa variada, visando à homogeneização da fertilidade do solo.

ABSTRACT Irrigated fruit growing in the São Francisco Valley has been standing out in the Northeast region of Brazil and the incorrect management of fertilization has caused problems of physical and / or chemical degradation of the soil. The work aimed to evaluate the spatial variability of the chemical attributes of a Latossolo Vermelho-Amarelo (Oxisol) grown with banana (Musa spp). The study was carried out in the irrigated perimeter of Nupeba in Riachão das Neves / BA. In an area cultivated for 18 years with silver banana fertigated by micro sprinkling. In April 2017 simple soil samples were collected at depths of 0 -0.20 m and 0.20 -0.40 m, from an experimental grid consisting of 40 georeferenced points and spaced every 10 meters. The soil samples determined: pH (H2O); Organic carbon; Phosphorus (P); Potassium (K+); Calcium (Ca2+); Magnesium (Mg2+) and Potential acidity (H + Al) and the sum of bases (BS), cation exchange capacity (CEC) and base saturation (V%) were calculated. The results of the analyses were evaluated using descriptive statistics and the geostatistics technique. The descriptive analysis identified the normality of the data. The spatial variability was confirmed, allowing the making of maps. The analyzed area has low fertility (V <55%) and the inadequate management of soil correction and fertilization can reduce the availability of nutrients for the implanted crop, making the soil susceptible to degradation with the use of irrigation. The distribution maps allow the visualization of the area, allowing the application of inputs with varying rates, aiming at homogenizing the soil fertility.

ABSTRACT The implementation of integrated agricultural production systems is considered a promising strategy for sustainable agricultural intensification in Brazil. This study aimed to evaluate the effects of different monoculture and integrated production systems on the microbiological attributes and organic carbon of soil from the Cerrado region in Piauí, Brazil. Soil samples were collected from the 0.0-0.10-m layer in the following systems: no-tillage (PD), pasture (PAS), exclusive eucalyptus cultivation (CEE), integrated livestock-forest system (IPF) and a native Cerrado (CN) area, which was used as reference. Total organic carbon (TOC) and nitrogen (NT) contents, microbial biomass carbon (CMIC), microbial respiration (MR), microbial quotient (qMIC), metabolic quotient (qCO2), as well as the activities of the hydrolysis of fluorescein diacetate (FDA), acid phosphatase, β-glucosidase and urease enzymes were evaluated. High TOC contents were found in the CEE, IPF and PAS systems, and high CMIC and qMIC values were found in the CN and CEE systems. The variables MR, qCO2 and enzymatic activity varied as a function of the management systems. The IPF and CEE systems caused improvements in the soil attributes, with increases in organic carbon and microbial biomass. The IPF integrated production system promoted improvements in the microbiological indicators of soil quality and was considered an environmentally sustainable agricultural production system. The transition from CN to agricultural areas caused changes in the soil microbiological indicators, which were perceived several years after anthropogenic intervention, indicating that even with the adoption of conservation systems, it was not possible to reestablish the soil microbial biomass.