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Area: 41 km2 | Component and its proportion of land system | ||||
1 15% | 2 10% | 3 60% | 4 10% | 5 5% | |
| CLIMATE Rainfall, mm | Annual: 850 – 1,100, lowest January (40), highest August (120) | ||||
Temperature, 0oC | Annual: 12, lowest July (8), highest February (18) | ||||
Temperature: less than 10oC (av.) June – September | |||||
Precipitation: less than potential evapotranspiration November - March | |||||
GEOLOGY Age, lithology | Paleocene unconsolidated clay, silt and sand | ||||
TOPOGRAPHY Landscape | Rolling hills in the northern upper reaches of the Gellibrand River catchment | ||||
Elevation, m | 75 - 210 | ||||
Local relief, m | 60 | ||||
Drainage pattern | Dendritic with some radial areas | ||||
Drainage density, km/km2 | 2.6 | ||||
| Land form | Hill | Valley floor | |||
| Land form element | Steep slope | Crest, upper slope | Crest, slope | Slope | - |
Slope (and range), % | 20 (10-45) | 12 (3-15) | 9 (1-15) | 13 (6-15) | 1 (0-2) |
Slope shape | Linear | Convex | Convex | Linear | Concave |
NATIVE VEGETATION Structure | Open forest | Woodland | Open forest | Open forest | Low woodland |
Dominant species | E. obliqua, E. radiata, E. viminalis | E. radiata, E. obliqua, E. nitida, E. ovata | E. obliqua, . radiata, E. viminalis; occasionally E. ovata | E. aromaphloia, E. obliqua, E. radiata, occasionally E. ovata | E. ovata, E. radiata, Melaleuca squarrosa |
SOIL Parent material | Clay, silt and sand | Colluvial sand on unconsolidated clay | Clay, silt and sand | Clay, silt and sand | Alluvial clay, sand and silt |
Description | Yellow gradational soils, weak structure | Grey sand soils, structured clay underlay | Mottled yellow and red gradational soils | Yellow-brown gradational soils, coarse structure | Grey gradational soils |
Surface texture | Sandy loam | Sandy loam | Fine sandy loam | Fine sandy loam | Fine sandy loam |
Permeability | High | Low | Moderate | Low | Very low |
Depth, m | >2 | >2 | >2 | >2 | >2 |
| LAND USE | Uncleared areas: Hardwood forestry for sawlogs, posts and poles; softwood plantations; nature conservation; passive recreation; water supply; forest grazing. Cleared areas: Beef cattle and sheep grazing; dairy farming; water supply | ||||
| SOIL DETERIORATION HAZARD Critical land features, processes, forms | Clay subsoils on steep slopes subject to periodic saturation are prone to landslips. Steep slopes are prone to sheet and rill erosion. | Low subsoil permeabilities leads to seasonal waterlogging. Low inherent fertility and permeable surface horizons lead to nutrient decline. | Low inherent fertility and phosphorus fixation lead to nutrient decline. | Dispersible clay subsoils of low permeability are prone to gully erosion. Clay subsoils on steeper slopes subject to periodic saturation are prone to landslips. | Low permeabilities and high water tables lead to seasonal waterlogging. High discharge rates along watercourses lead to some flooding and gully erosion. |