Regional-scale variability of soil properties in Western Cuba

- Clay content and SOM have low impact on the variability of the involved macroaggregate size classes.
- Calcium is crucial for the functioning of Cuban soils from Mayabeque and Artemisa.
- Increasing pH and compaction are in progress due to soil mismanagement.

The soils of Artemisa and Mayabeque provinces, in western Cuba, have a historical importance in Cuban agricultural productivity and have been subject to production- oriented practices and fragile protection from degradation. Very few contemporary studies about these soils are available. As a support to near-future management decisions, the objectives of this work are: i) to characterize the variability of some physical and chemical properties in the main agricultural lands of the Cuban provinces of Mayabeque and Artemisa, and ii) to identify relevant features associated to soil property changes and their possible impacts on near future decision making. Soil samples were taken in a 116 data point stratified-random-unaligned grid at two depths: 10-15 cm and 35-40 cm. The measured properties were: sand (Sa), silt (Si) and clay (Cl) content, organic matter content (SOM), bulk density (ρb), particle density (ρs), exchangeable cation content (Na+, K+, Ca2+, and Mg2+), pH, and the macroaggregate size distribution. An exploratory analysis illustrates the most outstanding issues of the variable distribution, their dependence on the involved soil depths and types, and the correlation between measurements. Some relevant spatial features associated to the behavior of the properties are identified with kriging spatial interpolation. Calcium content is shown to be a key property in soil functioning, mainly for its effect on macroaggregation. In contrast, Cl and SOM did not affect the soil structure patterns. Analyses suggest that Cuba's most productive soils are subject to severe degradation mainly from increasing pH and compaction, and therefore the adoption of conservation practices is crucial for their sustainability on the medium and long term.