Drip irrigation makes it possible to utilize saline water by eliminating direct contact between the water and the leaves, thus avoiding burns. Elephant concepts imports Israeli drip irrigation systems.

It also allows the use of grey-water because the water is delivered directly to the ground, minimizing health risks. While desalination and drip irrigation are more mature water areas with established revenue streams that are growing, Israel's water industry is also becoming known for having "the world's highest reused wastewater rate," and "the world's most advanced national water management system."

With Israel's continued focus on becoming the "Silicon Valley" of water technology title, several Israeli companies in these areas are starting to get heightened attention from both the media and investors. Israel recycles 75% of its water. The second largest water recycler is Spain, with 12% recycling.

The irrigation industry in Israel was a pioneer in developing innovative technologies and accessories like drip irrigation, automatic valves and controllers, media and automatic filtration, low discharge sprayers and mini- sprinklers, compensated drippers and sprinklers. The Computer – controlled drip irrigation saves huge quantities of water and enables the supply of fertilizers with the irrigation (fertigation). One of the principles of good agricultural practice is to provide developing plants with an adequate water supply - i.e., to avoid excess standing water and to prevent exposure to water shortage. Excessive amounts of water can cause poor aeration of the root system leading to inhibition of plant development, or wasteful percolation through the soil beyond the volume of the root system, or both. A water deficit places the plant under stress and interferes with its normal development. Avoiding water stress is particularly important in arid regions, where high solar radiation and low humidity enhance evapotranspiration (the process of loss of water from the ground surface and plant canopy). Efficient use of water is crucially dependent on advanced irrigation technologies, and nowhere more so than in arid-land farming.

Until about 50 years ago, crops in Israel were irrigated by surface (flood and furrow) irrigation. Surface irrigation is possible only when the ground is leveled and the soil type enables slow or moderate percolation of the water. Under arid conditions, surface methods of irrigation lead to severe loss of water by evaporation and by percolation beyond the developed root system, especially in the stages of germination and early development; moreover, between irrigation sessions the plants are exposed to stress. Another negative aspect of surface irrigation under arid and semiarid conditions is the process of soil salinization. The prevailing high temperatures and low humidity cause intense evaporation from the ground accompanied by accumulation of salts in the upper layers of the soil. The soil gradually becomes unfit for cultivation, both because of the destruction of the soil and due to the direct effect of the high concentration of salt on the plants. Vast areas in arid and semiarid regions of many countries affected by salinization have indeed had to be abandoned. Pressurized irrigation with sprinklers, introduced about 50 years ago, contributed much to modernizing agriculture and increasing water use efficiency. However, from the standpoint of agriculture in arid and semiarid regions, the most important development has been the introduction of drip irrigation.

Drip irrigation was developed in Israel and introduced into Israeli agriculture less than 35 years ago. Since then it has been disseminated all over the world with great success. Advantages of Drip irrigation Water is discharged uniformly along the lateral (pipe fitted with drippers) even on moderately sloping terrain. The invention of compensated drippers enables uniform irrigation of steeper slopes and long distances. Fertilizers can be supplied to the plant via the drippers together with the water (fertigation). Water and fertilizers are delivered directly to the root system rather than to the total area of the field, thereby economizing on both water and fertilizers. Drip irrigation causes salts to be continuously washed away from the root system, avoiding salt accumulation in the immediate vicinity of the roots when irrigating salinized soils or irrigating with saline water. High-quality drip irrigation equipment can last for fifteen to twenty years if handled properly.

A new, modified drip irrigation system has recently been developed for small-time farmers. Known as the "family drip system" or the "gravitation drip system", it is designed for use where both the water supply and the financial means are very limited. A simple container - such as a barrel or a hand-built container coated with a plastic layer - is filled with water and positioned about one meter above the ground. By opening a valve, the water flows by gravitation into the drip system. The container can be refilled using a manual pump, and fertilizer may be added to the water, as in the conventional drip system. Water use efficiency , is the ratio between the amount of water taken up by the plant and the total amount of water applied. Studies show that while it is about 45% in surface irrigation, in drip irrigation water use efficiency is doubled to about 95%. In soilless media culture, the typical leaching fraction applied in Israel to remove accumulated salt is between 3- and 50%. As a result, one third to one-half of the applied water drains out, carrying 130 mg/l nitrogen, 2- mg/l phosphorus, and 140 mg/l potassium as well as natural salts.

Approximately 1,000 kg of nitrogen, 1,600 kg of chloride and 800 kg of sodium are leached from one hectare of substrates, which are a potential polluting factor of more than 100 million sq.mr. of groundwater. In the last few years, around 25% of greenhouses with soiless substrates shifted from open to closed irrigation systems. This shift is even more impressive in rose production, where drainage water is recycled in over 50% of the greenhouses.

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