Land evaluation schemes
Land evaluation is about estimating the potential of land for alternative land uses.
The main land evaluation methods that have been used in Queensland are:
- land suitability
- land capability
- agricultural land classification (ALC)
- versatile cropping land (VCL)
- good quality agricultural land (GQAL).
Land suitability
Land suitability classification assesses the potential of land for a specific land use e.g. is the land suitable for furrow irrigated cotton, dryland maize, trickle irrigated apples. The specific land use is assessed against a range of limitations e.g. soil water availability, soil moisture, rockiness, slope, flooding.
Five land suitability classes are defined for use in Queensland, with land suitability decreasing progressively from class 1 to class 5. Classes 1 to 3 are suitable for agricultural production.
Class 1 land is highly productive, requiring only simple management practices to maintain economic production, with minimal degradation to the land resource. Class 5 land has extreme limitations that preclude the possibility of successful sustained use of the land in the proposed manner.
Land suitability is described in the Guidelines for Agricultural Land Evaluation in Queensland.
| Class | Description |
|---|---|
| 1 | Suitable land with negligible limitations |
| 2 | Suitable land with minor limitations |
| 3 | Suitable land with moderate limitations |
| 4 | Unsuitable land with severe limitations |
| 5 | Unsuitable land with extreme limitations |
Land capability
Land capability classification evaluates the potential of land for broadly defined land uses, e.g. cropping, pastoral, non-agricultural. In Queensland, it is generally only used for broad scale assessment of land.
The system uses eight classes, with limitations and hazards to agricultural and pastoral use becoming progressively greater from class I to class VIII, accompanied by a decreasing adaptability and choice of use. Lower-numbered classes (Classes I to III) are suited to more intense uses while higher-numbered classes are suited only to low-intensity agricultural use or conservation. Class VIII is unsuited to agricultural use.
Land capability is described in the Guidelines for Agricultural Land Evaluation in Queensland.
| Class | Description |
|---|---|
| I | Land suitable for all agricultural and pastoral uses |
| II | Land suitable for all agricultural uses but with slight restrictions for cultivation |
| III | Land suitable for all agricultural uses but with moderate restrictions for cultivation |
| IV | Land primarily suited to pastoral use but which may be safely used for occasional cultivation with careful management |
| V | Land that in all other characteristics would be arable but has limitations that make cultivation impractical and/or uneconomic |
| VI | Land that is not suitable for cultivation but is well suited to pastoral use |
| VII | Land that is not suitable for cultivation but on which pastoral use is possible only with careful management |
| VIII | Land that has such severe limitations that it is unsuited for either cultivation or grazing |
Agricultural land classification
Agricultural land classification (ALC) is a hierarchical scheme based on interpreted land evaluation information. It is used to assess the location and extent of agricultural land that can be used sustainably for a wide range of land uses, with minimal land degradation.
There are four classes (A, B, C and D). The classes imply a decreasing range of land use choice and an increase in the severity of land use limitations and/or land degradation hazard. Class A land has the greatest potential for producing the widest array of crops, while Class D land is unsuitable for any agricultural land use.
The ALC data is used to inform local government planning schemes and regional plans as required for the agriculture state interest provisions of the State Planning Policy. The dataset is also used in the Agricultural Land Audit, to formulate the Trigger Map for Strategic Cropping Land.
The ALC scheme is displayed spatially in the state-wide ALC dataset. The latest version is available for download from the Queensland Spatial Catalogue and can be viewed on the Queensland Globe.
Agricultural land classification is described in the Guidelines for Agricultural Land Evaluation in Queensland.
| Class | Description |
|---|---|
| A – Crop land Land that is suitable for a wide range1 of current and potential crops with nil to moderate limitations to production. | |
| A1 | Suitable for a wide range of current and potential broadacre and horticultural crops2. |
| A2 | Suitable for a wide range of current and potential horticultural crops only. |
| B – Limited crop land Land that is suitable for a narrow range3 of crops. The land is suitable for sown pastures and may be suitable for a wider range of crops with changes to knowledge, economics or technology. | |
| C – Pasture land Land that is suitable only for improved or native pastures due to limitations that preclude continuous cultivation for crop production. Some areas may tolerate a short period of ground disturbance for pasture establishment. | |
| C1 | Suitable for grazing sown pastures requiring ground disturbance for establishment; or native pastures on higher fertility soils. |
| C2 | Suitable for grazing native pastures, with or without the introduction of pasture, and with lower fertility soils than C1. |
| C3 | Suitable for light grazing of native pastures in accessible areas, and includes steep land more suited to forestry or catchment protection. |
| D – Non-agricultural land4 Land not suitable for agricultural use, including land alienated from agricultural use. | |
| Complex codes (A/C, A/D, B/C, C/D) Land that is a complex of class A, B, C or D land where it is not possible to delineate the land class at the map scale. The dominant class is the first code in the sequence and is assumed to be >50% of the area, but <70%5. | |
1 A wide range of crops is four or more existing crops of local commercial significance.
2 Horticulture includes intensively grown small crops (e.g. vegetables) as well as tree crops (e.g. grown for nuts, seeds or fruit). Silviculture (plantation forestry) is not included.
3 A narrow range of crops is three or fewer crop types (broadacre or horticulture) of local commercial significance. Silviculture (plantation forestry) may be included. Crops with similar agronomic requirements e.g. maize and grain sorghum, peaches and nectarines are not generally regarded as different crop types. Different management regimes (including irrigation strategies) for the same crop do not increase the number of crops.
4 Non-agricultural land includes land that cannot be placed in any of the other land classes and includes land such as urban areas and stream channels.
5 In cases where two or more land classes are equally dominant and none are greater than 50%, judgement is used to identify the most appropriate agricultural land class/es for the unit.
Versatile cropping land
Versatile cropping land is a 2-class system in which land is considered either versatile cropping land or not.
It is assessed based on the combination of crop requirements and the physical limitations of the soil type.
Where the soil properties meet a crop requirement, the crop is deemed suitable. The greater the number of suitable crops, the more versatile the land. If the land is suitable for four or more crops it is considered to be versatile cropping land (similar to an Agricultural Land Classification of Class A).
Good quality agricultural land
This was a 2-class system in which land was considered either good quality agricultural land (GQAL) or not. It was used in the planning framework associated with the now repealed State Planning Policy 1/92: Development and the Conservation of Agricultural Land.
GQAL was identified using the agricultural land classification classes. Class A land in all areas of Queensland was considered to be GQAL. See the State Planning Policy for more information on the current mechanisms to protect agricultural land in Queensland.
More information
Note: The information above is general information only and does not prescribe mandatory standards or practices.
Read more about this topic in the Guidelines for Agricultural Land Evaluation in Queensland.