Soils of Florida and the Caribbean: LRRs U and Z

Abstract

Soils across peninsular Florida (LRR U) and the Caribbean Islands of the US Virgin Islands and Puerto Rico (LRR Z) reflect the environmental conditions under which they formed. In LRR U, the majority of the soils have formed in sandy marine sediments although other types of parent materials including organic materials are important in parts of the region. The region is warm and humid, has low relief, especially near the coasts, and, because of the relief and abundance of depressions, has appreciable areas of poorly and very poorly drained soils with aquic moisture regimes. Soils across the region are commonly acid, moderately permeable, and have thin A horizons with relatively low contents of organic C. They are dominantly sandy Entisols and Spodosols although in areas with underlain by loamy sediments Ultisols are common. Soils in low relief and depressional areas are commonly Histosols . Across the islands comprising LRR Z, elevation ranges from sea level to more than 1220 m and local relief often results in steep terrain with soils subject to erosion and landslides. Soils across the region have developed in a very wide range of parent materials including volcanic materials such as ash and basalt , limestone, and coastal beach and dunal sediments. Rainfall varies widely across the islands. The range in topography , precipitation, and parent materials has resulted in soils with widely varying properties that include Ultisols, Oxisols, Inceptisols, Mollisols, Alfisols, Entisols, and Histosols. Soils in both LRRs are fragile and subject to degradation without proper management, and both regions have a common threat, rapid population growth, and urban development.