, Volume 98, Issue 1, pp 23–31 | Cite as

Spatial variability on slopes of Mediterranean grasslands: structural discontinuities in strongly contrasting topographic gradients

  • A. Puerto
  • M. Rico


Two grassland slopes showing a markedly different degree of homogeneity were investigated. In the classic sector sequence of exportation, transport and sedimentation diversity decreases from the highest to the lowest locations. The exportation sector is relatively homogeneous, while the transport sector is more heterogeneous but only under specific circumstances and over short distances (local level). By contrast, the sedimentation sector appears heterogeneous only over greater distances (regional level).

The sedimentation sector can be subdivided into two subsectors: wet and relatively dry. Between these, a third subsector can be observed, forming a transition band with intra- and inter-annual fluctuations of the ground water level, leading to very high diversity and moderate or low heterogeneity. As small changes in the availability of soil water can determine the spatial movement or disappearance of some of these subsectors, it is not surprising that the lower parts of the slopes show great variation in structure, which may explain frequent contradictions in the literature.


Diversity Heterogeneity Mediterranean grassland Slope Topographic gradient 


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Copyright information

© Kluwer Academic Publishers 1992

Authors and Affiliations

  • A. Puerto
    • 1
  • M. Rico
    • 2
  1. 1.Departamento de Ecología, Facultad de BiologíaUniversidad de SalamancaSalamancaSpain
  2. 2.Instituto de Recursos Naturales y Agrobiología (C.S.I.C.)SalamancaSpain

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