Cotton production systems in the Brazilian Cerrado: The impact of soil attributes on field-scale yield

The objective of this study was to assess the impact of different cotton (Gossipium hirsutum)-based management systems in the Brazilian Cerrado on soil's physical and chemical quality, using multivariate analysis techniques. The experiment was conducted in areas of cotton production in the state of Mato Grosso, located in the Cerrado biome and Cerrado/Amazon ecotone. Soil samples were obtained from 1162 plots of 10 ha each to evaluate the effects of cotton production systems. These plots were distributed in the main production sub region of the state of Mato Grosso. Soil samples were obtained in the 0 - 20 cm layer to evaluate chemical quality, carbon and nitrogen content, texture and bulk density. Seed cotton yield was estimated by harvesting 4 rows, each of 5 m length. Clay contents varied from a low of 54 to a high of 778 g kg(-1). Six cotton production clusters were established by means of a dendrogram. Principal component analysis explained almost 77% of all data variability, highlighting the effect of the evaluated soil attributes and altitude on cotton yields. The highest soil carbon (59.0 Mg ha(-1)) and nitrogen (3.5 Mg ha(-1)) stocks were observed in the clusters that used conservation agriculture practices. Clusters characterized by a high productivity were observed in regions with altitude of > 600 m, but without any common soil parameters. Cotton production areas with the longest cultivation periods were characterized by having the highest soil fertility. The highest yields (4195 kg ha(-1)) of cotton in the state of Mato Grosso were obtained in regions with higher alludes, associated with the use of conservation practices.