Understanding soils
Soil is the thin layer of material covering the earths surface and is formed from the weathering of rocks. It is made up mainly of mineral particles, organic materials, air, water and living organisms—all of which slowly yet constantly interact.
Most plants get their nutrients from the soil and in turn, are the main source of food for humans, animals and birds. Therefore, most living things on land depend on soil for their very existence.
Soil is a valuable resource that needs to be carfeully managed as it is easily damaged or washed or blown away. If we understand soil and manage it properly, we will avoid destroying one of the essential building blocks of our envrionment and our food security.
Soil degradation
Soil can be subjected to various forms of degradation that affects its productive potential. Some forms of degradation can be reversed while others can be difficult or uneconomic to treat.
Prevention is far better than cure and all land managers need to understand what forms of degradation are most likely to affect individual soils and landscapes. An important concept is using land in accordance with its capability.
Soils and land-use
A productive healthy soil that will support healthy plants has several characteristics. It needs to be deep, well structured, fertile, well drained and biologically active with a pH of 6 to 8. The combination of these features provides an environment that is ideal for plant growth.
A soil that is prized for its agricultural value may be less suitable for other uses. For example, some of our best cropping soils are cracking clays, but their capacity to shrink when dry and expand when wet creates problems for buildings and roads.
To assist land managers in determining land use options for their soil, a series of Soil Maps, Land Resource Bulletins and Land Management Manuals have been prepared for many parts of Queensland. In addition to information on soil types and soil properties, these resources may provide a regional overview of the land resources, climate, vegetation, and land management issues.
To access land resource and soil maps and reports, go to soil publications.
Further information
- Fact sheet L1—Understanding soil (PDF, 271K)*
- Fact sheet L40—Soil limitations to water entry (PDF, 61K)*
- Fact sheet L47—Understanding soil pH (PDF, 147K)*
- Paddock guide to determining soil texture (PDF, 113K)*
- Soil colour (PDF, 128K)*
- Understanding soil ecosystem relationships (USER)
* Requires Adobe Reader
Last reviewed 10 April 2012
Last updated 24 February 2010
