1 - Understanding your natural resources.
The arid zone is defined as areas which receive an average rainfall of 250mm or less.
The soils on your property will have different textures, rates of water infiltration, drainage and water holding capacity, and organic and nutrient levels. Soil type is closely linked to vegetation type and some plants are very specific about what soils they will grow on. For example, pearl bluebush only occurs on soils with high levels of lime and pH. Other plants however, may be more adaptable and grow on range of soil types.
The main mineral components of all soils are sand, silt and clay. Soil types are often described by the major mineral component and this description helps to explain the main characteristics of that soil. For example:
- Sands have large particle sizes and therefore large gaps between particles, allowing for rapid infiltration and drainage of water. Sands do not retain organic matter or dissolved nutrients well.
- Clays have very small particle sizes. These particles have strong bonds between each other and so will become sticky when wet but clod together when dry. As there is little space between the particles, water moves through the soil profile slowly, making these soils prone to water logging. However the strong particle bonds means that dissolved nutrients and organic matter are not easily washed away, meaning these soils have high fertility.
- Loams have roughly equal parts of sand and clay. This means loams combine the good characteristics of sand and clay, in that they readily drain water but have good water holding capacity and nutrient levels.
Another important descriptor for soils is pH. This describes if the soil acidic, neutral or alkaline and at either end of the pH scale, the availability of nutrients for plant growth can be limited.
Vegetation is usually described in terms of vegetation ‘communities’, each classified by the dominant plant(s), as well as the density and structure of the community, for example a bladder saltbush shrub land.
Soil and vegetation interact in a number of ways to produce the different land types. Management of vegetation is most important for sustaining production and soil protection. It is important to remember that many factors affect the health of vegetation including:
- grazing by domestic livestock
- grazing by other animals including feral (rabbits, goats, pigs) and native animals (kangaroos). Total grazing pressure is the sum of these animals and domestic livestock
- competition from weed species
- climatic conditions (including past and present trends)
- previous management
Your grazing management decisions will affect the vegetation on your property and its condition.
Water includes surface and underground supplies. It is not only quantity of water that can affect your production system but also quality. Domestic livestock have a low tolerance to poor quality water, especially when grazing plants that have a high salt content, such as saltbush.
Good management of water resources includes choosing the number and appropriate placement of watering points, controlling access to water points and adequate monitoring of supply and quality. It is important that each water point can adequately supply the number of cattle that are expected to drink there at any one point. This is means matching pumping and storage capacity to demand.
It is also important to consider what are the most efficient pumping and storage options (if applicable) for that particular water point. On sandy soils, it makes sense to use tanks rather than dams or ground tanks. You should also consider if it is possible to use solar pumping rather than windmills or generators.
What are the sources of water (water point types) and quality of water on your property? Have any of these water resources been mapped? Could the storage and pumping facilities be improved? Could the placement of water points be improved? Are they monitored, if so, how and how regularly?
Remotely monitoring watering points using telemetry systems can allow for increased management of watering points while saving money. Telemetry is a technology that allows data to be gathered and recorded without having to be at the location. Information is instead transmitted from measuring devices (such as flow meters) using radio or cellular phone technology.
Telemetry systems are currently capable of:
- switching pumps or irrigation systems on and off
- starting generators and monitoring pressure, temperature, voltage, etc
- monitoring dam or tank levels
- recording rainfall
- real time monitoring of security devices with an instant alarm if break-in occurs
- monitoring and controlling operation of electric fences
- remote reading of instruments such as weather and water flow gauges
- monitoring the status of gates at remote locations
- medicating water
- GPS vehicle tracking.
- remotely accessing digital cameras or a closed circuit television camera
Telemetry can be used to:
- reduce travel costs
- save time and labour
- reduce wear and tear on vehicles
- manage infrastructure that is hard to get to (due to, for example, wet season inaccessibility)
- create more security for remote infrastructure
The process of enquiring about a telemetry system involves:
- deciding which water points are to be monitored (either now or in the future)
- collecting GPS coordinates for each water point (taking information from maps or Google if suitable)
- prioritising the order of installation
In Australia, intricate relationships have developed over hundreds of thousands of years between the plants, animals and other organisms present in soil, water and environment in which they all live. Together they are called an ecosystem: a biological community of interacting species and their physical environment.
Biodiversity is therefore the degree of variation in life and in ecosystems. Species biodiversity is defined in terms of the number and type of different species, the individual uniqueness within the same species and a range in ages. To survive and cope with everyday living but also major change, it is important that not every plant and animal is the same age and type. For example, if a disease were to strike a plant or animal population and if it were all the same, it could potentially wipe out the lot.
An ecosystem which has a variety of species with mixed genetic makeup is considered healthier and more resilient to natural disasters and disease than systems with low diversity. This equates to a better chance of survival and also the ability to adapt to change.
If a key species is removed from within a community, one that is vital as a key source of food, then its removal or extinction will vastly affect the workings of the whole system. Do you know of any examples on your property where this has happened?