No industry relies on water more than agriculture. In fact, farming uses more of the world’s freshwater than any other endeavor. Any shortage of this critical natural resource puts farmers' livelihood in jeopardy, and farmers have created vast irrigation systems to ensure a steady supply. Without water, farmers could not feed the world's growing population.
Perhaps the most fundamental need farmers have for water is to water crops, or irrigation. An irrigation system allows farmers to regulate the amount and frequency of water application. There are a number of different irrigation methods employed throughout the world, including sprinkler and drip systems, controlled flooding, furrowing, subterranean irrigation and surface irrigation. Farmers must be especially intuitive when rainfall levels do not meet the desired or necessary quota for a particular season.
Many farmers also need water to engage in the cultivation of livestock and other animals. Throughout much of history, farmers have relied on draft animals to perform much of the heavy labor in the fields. This is particularly the case with regard to plowing, where oxen or other animals did all the pulling. In order to keep these animals healthy and hydrated, farmers must have significant access to fresh water. In indoor situations, watering is done through the use of a water trough. Outdoors, it may also be done with troughs or with watercourses.
On occasion, a bad drought can spell disaster for many aspects of the farmer's livelihood. Crops can dry up and disappear before harvest time. Droughts can also produce immense dust storms, which threaten the farm's livestock. These events are not rare but are part of normal climactic conditions in most regions. It is imperative that farmers amass water stores and reserves in times of plentiful water.
Even the most arid climates in the world have been successfully irrigated. In the medieval era, some of the most innovative and widely applied irrigation technologies emerged out of the Muslim/ Arab world. These included advances in wells (qanats), field terracing and dams. Because many of the Muslim rulers in Spain during this period hailed from Syria, they found their irrigation methods especially suited to the similar landscape of southern Iberia.