Penultimate Glacial

The last Glacial

Holocene -Transition from open vegetation to deciduous forest -Transformation of forest to open land (heath, shrubs, etc.) by early man (burning, grazing, cutting) -From approx BC: agriculture and intensified forest degradation -Late Middle Ages: gradual collapse of agricultural system and degradation (drift sand) -Reforestation from late 19th Century onward (introduction of fertilizers) -Trans

Distribution of driftsands

The genesis of ‘forten’ and blow-outs

Drift sand over Podzol in Coversand

Fortresses

Geology of the Hoge Veluwe Push moraine Ice melt water fan Snow meltwater valleys Snow meltwater fans Cover sands of eolian origin Snow meltwater fans with thin cover sand layer and later lakes due to water stagnation Driftsand with low relief Driftsand with strong dune relief Active driftsand Road Build-up area

The disappearance of drift sands between 1954 and 1960

Wind directions and speeds in the NPHV

Vegetation types of driftsands and their successional stages

Vegetation types of drift sands

Regeneration and conservation of drift sands Increase wind speed Remove vegetation Remove litter layer and topsoil Adequate source of sand that can be deflated Low level of atmospheric N-deposition Re

The Deelense veld Drift sand over Podzol: stagnation and fens

Deelense veld -Accumulative area (drift sand) -Drift sand layer over cover sand and fluvioglacial -Irregular relief with thinner (E) and thicker (W) drift sand over stagnative Placic horizon/Podzol- B horizon -To the West, Podzol eroded and thus infiltration -To the East, no drift sand and thus permeable Podzol at surface

Current situation -Strong decline of plant species characteristic for slightly buffered aquatic fen systems -Eutrophication (N) of the fens -Grass encroachment (Molinia) of the moist heath lands Causes Combination of: -No atmospheric input of fine mineral material -No buffering of acidity + increased nutrient level (P, K, etc.) -Atmospheric N-deposition - No atmospheric input es

Nature management NPHV - Wildlife and forest development - Fences and zones - Conservation/management at landscape scale - Historical landscapes - Biodiversity and management

Excursion 1.The Pollen: regenerated drift sands and their succession 2.Otterlose zand: old drift sand with early successional phases 3.The Deelense veld: fens and wet heathlands through stagnation on Podzol/placic horizon