Suitable sources of disturbance include landslips, wind and salt blast on sea cliffs, sand accretion on sand dunes and small-scale poaching by grazing animals. Disturbance as a result of direct human activity can also produce good habitat, both in semi-natural situations (such as footpaths and tracks on heathlands) and in brownfield contexts, although much depends on the scale and frequency of such human-caused disturbance (small-scale, patchy disturbance is more likely to produce good invertebrate habitat than large-scale and more homogeneous disturbance).
Habitat continuity is often associated with nutrient-deficient soils or exposure regimes that deflect ecological succession. Semi-natural biotopes supporting important examples of this assemblage type include sea cliffs, sand dunes, heathland and chalk downland. Arable land on nutrient-poor and freely-draining soils can also support interesting examples as can recently disused quarries and post-industrial and urban brownfield sites.