million hectares). Recent Soils are not restricted to particular
parent materials or climate zones, but occur on young land
surfaces, including alluvial flood plains, fans, sand dunes,
unstable hill and mountain slopes, and surfaces mantled by
young tephra deposits. Recent Soils occupy sites where
erosion or deposition occurs at rates low enough, or with
only thin deposits, to allow time for well-developed topsoils
to form. Recent Soils may also occur on sites with shallow
rock where the slow rate of rock weathering retards soil
profile development.
14.1.3 Variation Within the Recent Soil Order
Recent Soils comprise six soil groups (Fig. 14.3) with 15
subgroups. The six soil groups are;
Fig. 14.2 Distribution of Recent
Soils in New Zealand. The main
areas are mainly associated with
river flood plains
14.1 Important Features of Recent Soils
217
parent materials or climate zones, but occur on young land
surfaces, including alluvial flood plains, fans, sand dunes,
unstable hill and mountain slopes, and surfaces mantled by
young tephra deposits. Recent Soils occupy sites where
erosion or deposition occurs at rates low enough, or with
only thin deposits, to allow time for well-developed topsoils
to form. Recent Soils may also occur on sites with shallow
rock where the slow rate of rock weathering retards soil
profile development.
14.1.3 Variation Within the Recent Soil Order
Recent Soils comprise six soil groups (Fig. 14.3) with 15
subgroups. The six soil groups are;
Fig. 14.2 Distribution of Recent
Soils in New Zealand. The main
areas are mainly associated with
river flood plains
14.1 Important Features of Recent Soils
217