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Wind erodibility is the inherent propensity of soil to be entrained and transported by wind. Wind erodibility is independent of site conditions such as climate, vegetative cover or surface roughness. Wind erodibility is measured using a nine-class soil classification, based on the soil's resistance to wind erosion in cultivated areas (USDA 1993). Wind erodibility group allocation is based on soil texture, organic matter, calcium carbonate content, rock content and aggregate stability.

Wind erodibility is high at 13% (3710 profiles) and moderate at 46% (13031 profiles) of the profiles recorded in SALIS. This indicates that there is a potential for large-scale loss of topsoil through wind erosion in NSW.

There are many places in NSW where there is no formal record of measured soil attributes. This can be seen in the large blank areas shown on the map. Knowledge of the condition of our soils is far from complete, but the NSW Soil Landscape mapping program continues to fill in the blanks. Data from over 31,000 profiles in SALIS was used to produce this map for the SoE 2000 report.

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Inherent Sheet Erosion Risk (ISER) is the long-term susceptibility of a parcel of land to sheet erosion if the soil is left bare and no erosion control management is employed. ISER is a function of the intrinsic attributes of the land that contribute to potential soil loss (in tonnes of soil per hectare per year) including rainfall erosivity, topsoil soil erodibility and slope gradient, if there is no protective vegetation (Rosewell & Edwards 1988).

Soil loss through sheet erosion of over 100 tonnes/hectare/year is predicted at 31% (5139 profiles) of the sites in SALIS. Such erosion would result in large-scale removal of topsoils and sedimentation of streams.

There are many places in NSW where there is no formal record of measured soil attributes. This can be seen in the large blank areas shown on the map. Knowledge of the condition of our soils is far from complete, but the NSW Soil Landscape mapping program continues to fill in the blanks. Data from over 31,000 profiles in SALIS was used to produce this map for the SoE 2000 report.

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pH is a measure of acidity and alkalinity. Technically, it is the negative log of the concentration of hydrogen ions in a solution. Acid soils are often leached of many soluble ions and are commonly deficient in major plant nutrients such as calcium, magnesium, nitrogen, phosphorus and molybdenum. Metal ions may also be soluble in toxic concentrations. Excessive soil alkalinity reduces the availability of some essential plant nutrients such as iron, manganese, copper, cobalt and zinc.

Soil sample test results for surface soils that have both field and laboratory pH measurements were regressed and the relationship between Raupach, 1:5 soil:water and 1:5 0.1mol CaCl₂ was established.

The pH results in SALIS show that 90% (22484 profiles) of the sites are acidic (pH < 6.5) and 2% (473 profiles) are alkaline (pH > 7.5). Acidity and alkalinity may both result in a reduction of plant growth due to trace element deficiencies and toxicities.

There are many places in NSW where there is no formal record of measured soil attributes. This can be seen in the large blank areas shown on the map. Knowledge of the condition of our soils is far from complete, but the NSW Soil Landscape mapping program continues to fill in the blanks. Data from over 31,000 profiles in SALIS was used to produce this map for the SoE 2000 report.

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Surface soil acidification hazard is the amount of acid that needs to be added to bring soil pH to critical level. Critical soil pH is considered to be 5.5 in 1:5 soil:water because below this pH level aluminium becomes increasingly soluble and toxic to plants (Isbell 1996). An equation using clay percent, organic carbon content and pH 1:5 soil:water (Bui 1998) was used to calculate acidification hazard.

Of the profiles recorded in SALIS 35% (8688 profiles) are below the critical level of 5.5 and 33% (8153 profiles) are at a high or very high risk of reaching the critical level. Making their management important to avoid reaching the critical level and subsequently limiting plant growth.

There are many places in NSW where there is no formal record of measured soil attributes. This can be seen in the large blank areas shown on the map. Knowledge of the condition of our soils is far from complete, but the NSW Soil Landscape mapping program continues to fill in the blanks. Data from over 31,000 profiles in SALIS was used to produce this map for the SoE 2000 report.

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A sodic soil contains sufficient exchangeable sodium to adversely affect plant growth and soil stability. Many sodic soils are sodic because they have been saline (Houghton et al. 1986). As the salt leached away some sodium remained attached to cation exchange sites on negatively charged soil particle surfaces. Today the sodium remains and these previously saline soils are still sodic.

Sodic soils are prone to dispersion, are often highly erodible and have low wet bearing strength. Sodic soils are also relatively impermeable to water, reducing productivity and increasing run-off and erosion problems.

When dry, sodic soils are often dense and set hard. As sodic soils collapse when wet, surface seals and crusts often inhibit seedling emergence. Sodic soils are prone to soil structure decline and require careful management.

Exchangeable sodium percentages where calculated were laboratory test results were available. Great Soil Groups were also used to identify sodic soils.

The results in SALIS show that 15% (1130 profiles) of the sites recorded with sodicity are strongly or very strongly sodic making them highly susceptible to dispersion, highly erodible, low wet bearing strength, impermeable to water, reducing productivity and increasing run-off and erosion problems.

There are many places in NSW where there is no formal record of measured soil attributes. This can be seen in the large blank areas shown on the map. Knowledge of the condition of our soils is far from complete, but the NSW Soil Landscape mapping program continues to fill in the blanks. Data from over 31,000 profiles in SALIS was used to produce this map for the SoE 2000 report.