Soil quality indicators in Vertisols under sugarcane

Maintaining or improving soil quality is crucial for agricultural productivity. This study was undertaken on the north coast of Cuba with the objective to select soil quality indicators to characterise Vertisols. For the selection of soil quality indicators, we have conducted four field experiments where organic fertilisers (sugarcane filter cake, compost) and natural minerals (dolomite, zeolite) were applied. Sugarcane (Saccharum officinarum L.) was used in all experiments. Soil properties were determined such as the amount of water-stable aggregates, permeability, plastic limit, pH in water, pH in KCl, organic matter, P₂O₅ and K₂O. The sugarcane yield components such as cane yield (t ha^?1) and sucrose yield (t ha^?1) were evaluated. Principal components analysis and simple regression analysis were also performed. Both organic matter and water-stable aggregates were closely related to cane yield, with r values of 0.87–0.97. The properties with best responses to treatments over time were permeability, water-stable aggregates, degree of soil aggregation and organic matter; therefore, they can be considered as soil quality indicators for the studied Vertisols.