GROWING MORE FOOD WITH LESS WATER.
WATER
Expectations for the population to grow by 40 per cent to more than 9 billion by the year 2050 have raised the global question of how to grow more food with less water. With agriculture responsible for 70 per cent of all freshwater withdrawals, efficient and sustainable water use is needed for our own generation and future generations.
With our global water crisis in mind, we have created this resource to provide factual water news and information.
- Plant dry land crops that require less water
- Increase moisture-holding capacity of dryland
soils
- Use mulches and cover cropping
- Employ minimum tillage practices
- Increase soil organic matter
- Decrease evaporation by planting windbreaks
- Increase water-use efficiency on irrigated land
DRIP IRRIGATION FACTS
-
Micro-Irrigation: Trickle, Drip, or Spray
- Benefits
- More than 90% efficient
- Can be used on hilly land
- Can use relatively saline water
- Programmable
- Concerns
- Expensive to install and maintain
- Clogging of water emitters if water quality is poor
- Can cause localized salinity at edge of wetting zone
DRIP IRRIGATION
In a world that is experiencing droughts, floods and variable climatic conditions, the careful use of water resources is becoming more and more important.
Globally, 71 per cent of withdrawn freshwater is used for irrigation and in order to irrigate some areas, rivers are dammed to collect the water displacing people and destroying wildlife habitat.
Irrigation depletes rivers and aquifers and it also degrades water, soil, and wildlife habitat.
Governments and environmental organisations around the world are now encouraging a more sustainable use of water and encouraging sustainable irrigation.
The advice urges only the amount of water that can be replenished through recharge should be extracted and the water should be applied efficiently to minimise losses during delivery to site and application to crops.
Only the amount of water the crop needs should be applied and to minimise downstream environmental damage the water quality needs to be protected to protect irrigation water.
However, water is essential for crop production and where rainfall does not occur naturally, or in the right amount at the right time, farmers must irrigate.
They are being forced to look at ways of conserving water and nutrients, avoiding unnecessary run-off and at the same time maximising crop yields.
To achieve these aims requires careful use of the water available and systems to get the water to the crops to maximise the effects of the water and nutrients are becoming more and more important.
The use of irrigation systems has been part and parcel of agriculture around the world for centuries but now farmers are looking for systems that make the most of the resources available.
To this end, drip irrigation systems can offer the benefits of improved profit by increasing crop yields while reducing costs and water usage.
They can also help to reduce other costs such as labour and also chemical use by delivering water and nutrients to where they are most effective.
Drip irrigation has been developed and developing for decades provides systems that deliver water and nutrients to the plants' roots avoiding unnecessary wetting of the plants' leaves.
Drip irrigation is different from gravity or sprinkler irrigation and is set up to suit specific situations. It is increasingly becoming popular with organic farming operations.
Drip irrigation (sometimes called trickle irrigation) works by applying water slowly, directly to the soil. The high efficiency of drip irrigation allows the water to soak into the soil before it can evaporate or run off and the water is only applied where it is needed, (at the plant's roots) rather than sprayed everywhere.
DRIP IRRIGATION MAINTENENCE |
|
Clogging Problem | Maintenence Treatment |
Suspended materials | Filter water with 200 mesh filter |
Chemical precipitation of bicarbonates and iron | Add acid to irrigation line |
Biological Growth | Add chlorine to irrigation line |
Drip systems are simple and also forgiving of errors in design and installation.
The application of water through drip irrigations is more uniform than other systems and there is less loss of water than in other systems such as through wind on sprinkler systems.
While sprinkler systems are considered to be between 75 and 85 per cent efficient, drip irrigation systems are said to be 90 per cent efficient or more.
Because application is more uniform and constant to the areas where it is needed there is also less loss through run-off or percolation and it does not flow onto non-targeted areas, where it is wasted. It is also highly adaptable to the environment and location – whether the land is hilly or oddly shaped.