ABSTRACT The present study aimed to evaluate the accumulation and distribution of Cu and Zn fractions in the profile of an Inceptisol by application of fungicides with a previous history of apple cultivation in southern Brazil. Stratified soil samples (0.0 – 0.025 m, 0.025 –0.050 m, 0.05 – 0.10 m, 0.10 – 0.15 m, 0.15 – 0.20 m and 0.20 – 0.40 m depth) were collected in two apple orchards (8 years old and 18 years old), and in a native pasture area adjacent to the orchards. The soil was subjected to analysis of physical and chemical properties and to chemical fractionation of Cu and Zn. The fractions of soluble, exchangeable, organic, residual and total Cu and Zn accumulated in the topsoil (0.0 – 0.025 m) of the orchards, being higher in the orchard cultivated for 18 years. Most Cu, especially in the topsoil of the 18 years old orchard, accumulated in the less stable organic fraction, which can potentiate toxicity to plants and transfer Cu e Zn to ground water. In deeper layers, Cu was also distributed in the residual and mineral fractions, which are more stable. Most Zn in the soil of the apple orchards was distributed in the mineral and residual fractions, which have low mobility and low potential toxicity to plants.

ABSTRACT Phosphorus (P) applications at dosages higher than the necessary may cause P buildup in the soil labile fractions and, consequently, pollution of water sources. This study aimed to assess accumulation of P fractions as well as the parameters of adsorption isotherms in soil profiles having a history of application of phosphate fertilizers and cultivated with apple trees. Soil samples were collected from an area with no history of cultivation and 2 apple orchards cultivated for 8 (P8) and 18 (P18) years, in the city of Urubici, Santa Catarina, southern Brazil. Soil samples were air dried, sieved in a 2-mm mesh, and subjected to chemical analyses (P adsorption) besides P chemical fractionation. Applications of phosphate fertilizers to the orchards, particularly P18, increased the inorganic and organic concentrations of P in all fractions. The distribution of P in organic and inorganic forms in the planted soils was similar to the distribution observed for the native vegetation soil. The highest inorganic labile P fraction, the lowest maximum P adsorption capacity, and the highest equilibrium concentration values at P18 are indicators of a higher environmental pollution risk of the orchards soils compared to the native soil.

A aplicação de fontes de nitrogênio (N) em pomar de macieira pode incrementar o teor do nutriente no solo ao longo do ciclo, afetar o estado nutricional e a produção, mas parte do N pode ser perdido por lixiviação. O trabalho objetivou avaliar o teor de N total em folhas, a produção e o fluxo de N no solo e na solução, em um pomar de macieira com a aplicação de distintas fontes de N, em um experimento em Urubici (SC). Plantas foram selecionadas, receberam a aplicação de ureia (U), ureia peletizada (UP) e cama sobreposta de suínos (CS); além de um tratamento sem adubação (SA). Nas safras 2011/2012 e 2012/2013 foram analisados teores de N em folhas completas e mensurados o crescimento das plantas e a produção de frutos. Foram coletadas amostras de solo e de solução, e analisados os teores de N-NH4 + e N-NO3 - ao longo da segunda safra. Aplicações de U, UP e CS aumentaram o rendimento da macieira no segundo ano, mas o teor de N em folhas não foi afetado nas duas safras. A aplicação de N afetou o fluxo de formas do nutriente no solo e na solução ao longo do ciclo da cultura, com pequenos incrementos nos teores do solo e da solução em períodos próximos à aplicação das diferentes fontes de N

The application of nitrogen (N), from different sources, in apple orchard can increase soil N content, affecting the plant's nutritional status and yield, but part of the N can be lost by leaching. With the aim of assessing plant nutritional status and yield, and N flow in the soil and solution an experiment was carried out in in an apple orchard in Southern Brazil, applying different N source. Selected plants received the following treatments: application of urea, pelletized urea or pig deep litter, besides a control without fertilization. In the 2011/2012 and 2012/2013 crop seasons, N contents in whole leaves were analyzed and plant growth and fruit yield parameters were measured. Soil and soil solution samples were collected and the NH4 +-N and NO3 --N contents were analyzed during the second crop season. Application of pig deep litter, urea and pelletized urea increased apple yield in the second crop season, with no differences among treatments in leaf total N content at any time period. The application of N to the soil affected the flow of nutrient forms in the soil and in the solution throughout the apple crop cycle, with small increases in soil and in solution contents in periods near the application of the different N sources to the soil