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The context of processes and characteristics of soil erosion and land degradation in Mediterranean lands is outlined. The concept of connectivity is explained. The remainder of the chapter demonstrates development of methods of mapping, analysis and modelling of connectivity to produce a spatial framework for development of strategies of use of vegetation to reduce soil erosion and land degradation. The approach is applied in a range of typical land use types and at a hierarchy of scale from land unit to catchment. Patterns of connectivity and factors influencing the location and intensity of processes are identified, including the influence of topography, structures such as agricultural terraces and check dams, and past land uses. Functioning of connectivity pathways in various rainstorms is assessed. Modes of terrace construction and extent of maintenance, as well as presence of tracks and steep gradients are found to be of importance. A method of connectivity modelling that incorporates effects of structure and vegetation was developed and has been widely applied subsequently.

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The Cabeza de Vaca eruption is the most recent, damaging, and long-term eruption since historical records at La Palma. We analyzed geophysical parameters (seismicity, surface deformation, thermal anomalies, volcanic activity) with the aim to reconstruct the temporal development of the magma plumbing system. The seismic sequence (>9000 events, mbLg ≤5.0) can be grouped into nine distinct phases, which correspond to well-separated spatial clusters and distinct earthquake regimes. A strong premonitory thermal anomaly was calculated on July 2021 at the South of La Palma. The source of the magmas (40-20 km depth) storage withing the upper mantle. The second source (<15 km depth) indicated a short-term stagnation of alkaline magma within the lower crust, near the Moho. These earthquakes outline delineating the magma pathway. Just before and immediately after the eruption (phases 2 and 3), the high-frequency seismicity in the mantle disappears completely, reappearing ten days after the eruption started. The pattern of deformation began before the eruption with a breakpoint around September 11, after which, deformation accelerated sharply followed by a stabilization in phase 3 and a decrease in following phases. The level of deformation suggested that a shallow magma intrusion was stablished. Based in the historical eruptive pattern, it could be dilucidated that: a) the volcano could enter in a prolonged phase of tranquility or, b) that a new eruption occurs between ca . 2045 and 2065 with a duration slightly lower than the recent one. Therefore, assuming a pessimistic scenario, an adequate territorial planning is meritorious.