Chemical and physical attributes of five Oxisols as predictors of shoot dry mass of white oats

ABSTRACT In no-tillage systems, oats are one of the species most used as a cover crop in the subtropical region of Brazil. This study aims is to determine a set of chemical and physical properties of five Oxisols after surface liming, and to determine whether these properties are related to the shoot dry mass production of white oat (Avena sativa L.) variety IPR Aphrodite, in order to establish a model to predict its yield.. For this purpose, a field experiment was conducted during 2015 and 2016 in Londrina County in the State of Paraná with samples of B horizon collected from five Oxisols with clay content ranging from 15-80 dag kg-1 arranged in microplots since 2004. Soil pH in CaCl2, calcium, magnesium, potassium, potential cation exchange capacity (CEC), base saturation, microporosity, total porosity, field capacity, permanent wilting point, clay and sand of the Oxisols were the parameters that most influenced the dry mass production of white oats. Oxisol extrinsic factors such as values pH and base saturation, as well as the calcium and magnesium contents, positively altered with surface liming, boosting the production of oat dry mass production.

摘要 在免耕系统中，燕麦是巴西亚热带地区最常用的覆盖作物之一。本研究旨在明确5种氧化土（Oxisols）经地表撒施石灰后的一系列化学与物理性质，并探究这些性质与白燕麦（Avena sativa L.）品种IPR Aphrodite的地上部干物质产量之间的关联，从而建立可预测其产量的模型。为此，2015年至2016年在巴拉那州隆德里纳县开展了田间试验，供试土壤为自2004年起设置的微区试验中采自5种黏粒含量范围为15~80 dag kg⁻¹的氧化土B层样品。本研究测定的氧化土参数包括以氯化钙（CaCl2）浸提的土壤pH值、钙、镁、钾含量、潜在阳离子交换量（CEC）、盐基饱和度、微孔隙度、总孔隙度、田间持水量、永久萎蔫点、黏粒与砂粒含量，上述参数均对白燕麦地上部干物质产量具有显著影响。氧化土的外在影响因素如pH值、盐基饱和度以及钙、镁含量，会因地表撒施石灰而正向提升，进而促进燕麦地上部干物质量的积累。