Nunniong (Ng)

A study of the land in the Catchment of Gippsland Lakes - Vol 2 - land system Nunniong- geo

Area: 98 sq. km (0.5%)

The Older Volcanic flows were mainly valley fills but subsequent erosion has often removed the softer surrounding sediments and left the basalts as cappings on ridges. Such cappings in alpine or subalpine tracts are mapped in Nunniong land system. These areas, which have a relatively flat to gently undulating topography and rocky outcrop at breaks of slope, are usually flanked by the steep slopes and cliffs of the ridge-and-ravine terrain. Concave, treeless plains with central bogs and some small lakes are common, having formed under earlier lacustrine and paludal conditions before competent drainage developed on the lava flows.

A cold climate and high rainfall have combined to produce friable, acidic soils with a high concentration of organic matter in the topsoil and with little textural change down the profile. Soils are generally shallow and basalt floaters are common. Nutrient status is presumed to be moderately high because of the basaltic parent materials.

The dominant vegetation is grassy or shrubby woodland I with tussock grassland on plains of lacustrine origin. Heath and sedgeland occur in seepage areas and, along with Sphagnum, spp. in bogs.

A study of the land in the Catchment of Gippsland Lakes - Vol 2 - land system Nunniong- image

Wooded, gentle slopes adjacent to a prior lake bed

CLIMATE Rainfall, mean (mm) Temperature, mean (°C) Seasonal growth limitations	Annual 900 - 1600; lowest January or February (70 - 100), highest August or September (150 - 180) Annual 4 - 8; lowest July (-2 - 0), highest February (11 - 13) Temperature <10°C (av.): April - October Rainfall < potential evapotranspiration: February; frequent winter snow
GEOLOGY Age, lithology	Tertiary basalts (Older Volcanics)
PHYSIOGRAPHY Landscape Elevation range (m) Relative relief (m) Drainage pattern Drainage density (km/km²)	Gently undulating plains on residual interfluve basalt cappings 1040 - 1700 40 - 160 Dendritic 0.4
PRESENT LAND USE	Uncleared: summer bush grazing of cattle; apiculture (limited); recreation — bushwalking and skiing; small areas in Bogong National Park

A study of the land in the Catchment of Gippsland Lakes - Vol 2 - land system Nunniong- cs

A study of the land in the Catchment of Gippsland Lakes - Vol 2 - land system Nunniong- graph

LAND COMPONENT Percentage of land system Diagnostic features	1 65 Gentle slopes, rises and flat areas	2 20 Treeless grassy lower slopes bordering depressions, often of prior lakes	3 10 Stony hills, scarps and ravines	4 5 Small lakes; peat bogs, often drained by small streams; seepage areas
PHYSIOGRAPHY Slope %, typical and (range) Slope shape	5, (0 - 10) Various; uneven	5, (0 - 15) Concave	20 - 25, (10 - 40) Straight or convex	1, (0 - 2) Straight or concave
SOIL
Parent material	Basalt
Description	Black loam to clay loam merging into brown loam to clay loam; shallow	Black organic loam to clay loam merging into brown loam to clay; mostly shallow	Black loam to clay loam merging into brown loam to clay loam; shallow	Organic remains and alluvium Shallow black fibrous peat or muck overlying mineral soil or bedrock
Classification	Lithosols/Brown Earths/Alpine Humus Soils Um5.51, Um6.12, Um6.41, Gn4.31, Um6.21, Um6.24		Brown Earths/Alpine Humus Soils Um6.21, Um6.12	Humic Gleys, Acid Peats -
Surface texture	Loam to clay loam		Loam to clay loam	-
Surface consistence	Soft to slightly hard		Soft to slightly hard	-
Depth (m)	0.2-0.5	0.3-0.9	0- 0.4	1.0-2.0
Nutrient status	Moderate	Moderate	Moderate	Low
Available soil water capacity	Moderate to high	Moderate to high	Moderate to high	High
Perviousness to water	Moderate to rapid	Moderate to rapid	Moderate to rapid	Moderate to rapid
Drainage	Moderately good to good	Moderately good to good	Good	Very poor to poor
Exposed stone (%)	Very variable; 1 - 75	0 - 15	30 - 80	0 - 15
Sampled profile number	-	6	-	-
NATIVE VEGETATION Structure of vegetation and characteristic species of dominant stratum (+ Predominant species)	Grassy or shrubby woodland I, occasionally open forest I or II: E. pauciflora generally predominant, sometimes with E. stellulata or E. rubida; E. nitens occasionally predominant	Tussock grassland: Poa spp.	Tussock grassland: Poa spp. Shrubby woodland I: E. pauciflora Shrubby open forest II: E. rubida	Tussock grassland Bogs with Sphagnum sp., Epacris paludosa and/or Carex gaudichaudiana and other Cyperaceae and Juncaceae

Disturbance	Affected process and trend	Primary resultant deterioration			Casual activities	Primary off-site process
Disturbance	Affected process and trend	Form	Susceptibility of components	Incidence with components	Casual activities	Primary off-site process
Alteration of vegetation: — reduction in leaf area, rooting depth and/or perenniality	Reduced transpiration, resulting in: a) increased deep percolation b) decreased fog drip c) increased rate of snow melt	Nutrient loss - -	Not determined - -	Not determined - -	Removal of trees Removal of trees and understorey Removal of trees and understorey	Increased movement of water to groundwater; increased base-flow of streams Decreased base-flow of streams Increased spring and decreased summer stream flow
Increased exposure of surface soil	Increased overland flow and soil detachment Increased frost heave and soil detachment	Sheet and rill erosion Wind, sheet and rill erosion	1,2,3; low 1,2,3; low	Uncommon: locally severe Uncommon	Road, dam building and other earth-moving activities, trafficking by stock and vehicles. Removal of vegetative ground cover	Increased flash flows and sediment load Increased flash flows and sediment load
Increased physical pressure on soil	Increased compaction With Reduced infiltration	Structure decline Sheet and rill erosion	1,2,4; high 3; moderate 1,2,3; low	Uncommon Uncommon; locally severe	Increased trafficking, export of organic matter As for sheet and rill erosion above	- Increased flash flows
Increased soil disruption	Increased soil break-up	Gully erosion Streambank erosion	1,2; moderate 4; low – moderate 4; moderate	Uncommon Uncommon	As for sheet and rill erosion above As for sheet and rill erosion above	Increased sediment load Increased sediment load
Comments: Regeneration of vegetative cover is slow and difficult because of the unfavourable climate.

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