Sustainable agriculture requires using renewable resources as far as possible and non-renewable resources as sparingly as possible. However, sometimes the case is that what should be a renewable resource, if not managed properly, is be counted as a non-renewable resource. One such element is water supply.
We tend to think of water as a perpetually self-replenishing resource. After all, surely the water we use, even the water we waste, goes back into the water-cycle, raining back down to the ground? Statistics are not on our side to support this optimism. By 2025, two thirds of the population will be living in a water-stressed area.
There are several key areas in water conservation, such as protecting the water supply from the chemical runoff of fertilisers, medicines and pesticides, as well as preventing salinisation, which is the accumulation of soluble salts in soil as a result of incorrect irrigation techniques.
One of the areas of water conservation that needs to be given more consideration, however, is the quantity of water being used. While the chemical pollution of water is often given a lot of attention, the simple matter of how much water is being used is sometimes forgotten, perhaps because many still think of water as a renewable resource.
Using Less Water
Some of these measures may require start-up money, and so the case may be that financing strategies have to be thought out, such as applying for personal loans, or looking for investment opportunities.
- Ideally, crops would be grown in areas where there is a large enough rainfall to suit agricultural needs naturally. This is not always practical, however, and so additional irrigation is needed. Nevertheless, choosing to rather plant less ‘thirsty’ crops in lower rainfall areas as far as possible can help.
- Irrigation needs to be customised depending on the type of crop grown, the stage of growth the crop is in, and the current weather, so as to not use more water than is necessary.
- Also important is to check that the irrigation equipment is well-maintained, so that water is not being wasted.
- An online system can be consulted for advice on the quantity of irrigation needed, factoring in temperature, moisture, dew, rainfall, and solar radiation data, collected from weather stations across the cropping area every 15 minutes.
- Rainwater can be collected and stored to boost irrigation supply, such as by building small dams and earth ponds.
- Putting organic matter back into the ground helps soil retain water better.
- A good way to save water is through drip irrigation. Drip systems apply small amounts of at frequent intervals using a network of tubes. This not only saves water, but improves yields and reduces fertiliser and pesticide use. However, drip irrigation can be more expensive.
- Soil erosion can also limit available water, by contaminating the water supply with sediment. There are various ways of preventing this.
Although these methods take change of habit, research, effort and even money, they can prove beneficial in the long run. Even if a loan needs to be paid off in order to implement sustainability, the cost is put into perspective when considering the financial troubles run into should water become too scarce.