Drip Irrigation Systems

The basic system consists of LDPE, HDPE, or PVC hose or tube in which the emitters are installed as per spacing provided during manufacturing. Fertilizers and sanitation agents are kept in specified vessels. 

The circnlafing mains consist of 20- to 25-mm plastic pipe extending from fertilizer vessels and run past every in field valve and then vessel. Also passing through every in-field valve in the system in conjunction with fertilizer mains in a high-pressure clear water main connected to a pressure system, which does not circulate. Injection of fertilizer can be done as per requirement of crop in the field, at a single point as well as at multiple points. The advantages of the system can be summarized as follows  

Saving of Water Due to localized application of water to the root of the plant, surface evaporation is reduced, runoff is decreased, and deep percolation loss is avoided resulting in up to 60% saving in water used in conventional irrigation. 

Better Field of Crop Increase in root length as well as crop yield has been experienced due to slow and frequent supply of water for example, a 12% increase in strawberries in California. 

Saving in Labor and Energy Scientific design of the system using principles of hydraulics would require labor only to start and stop the operation and less energy for pumping less water at lesser pressure than open-field system. 

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A.S. Felsot, R.G. Evans, and J.R. Ruppert, Field studies of imidacloprid distribution following application to soil through a drip irrigation system , in Terrestrial Field Dissipation Studies Design, Interpretation and Purpose, ed. E.L. Arthur, V.E. Clay, and A. Barefoot, ACS Symposium Series No. 842, American Chemical Society, Washington, DC (2003). 

Ajwa, H. A., Trout, T., and Mueller, J. (2002). Application of alternative fumigants through drip irrigation systems. Phytopathology 92,1349-1355. 

Beneficial and Harmful Effects. At low levels, sulfur dioxide in the atmosphere is not harmful to crops, but damage can occur at excessive levels (305—309). Crops differ gready in their sensitivity. Forest damage attributed to acid rain is often cited but the observed symptoms seem to have multiple causes and the contribution of sulfur acids is unspecified. The sulfur in precipitation is, up to a point, beneficial to plant growth because sulfur is an essential nutrient. Lessening the sulfur content of the atmosphere requires that supplementary sulfur be provided in fertilizer to some crops some crops already require supplementary sulfur. Sulfur dioxide itself has been found useful in drip irrigation systems (310,311) and in calcareous soils (308). Small field generators have been developed for this purpose. 

Some vineyardists are installing drip irrigation systems. Insufficient data exist to assess their utility. One major vineyard is investigating the possible use of a combination of solid-set sprinkler and drip system. The solid set would be used to maintain a cover crop and for applications of waterborne pesticides, herbicides, and nutrients. The drip system would be employed for deep irrigation of the grape vines. Such a combination system is not yet installed in a vineyard. 

Water use can be reduced by up to 66% without compromising yields by substituting drip irrigation systems for furrows (Siddalingaswamy et al., 2007). This will have additional benefits, reducing electricity to run the pumps. A number of silk-producing areas of India (e.g. Kolar district) are under severe water stress and electricity subsidies pose a large fiscal burden (Kimmich, 2013 World Bank, 2010). 

Use drip- and soaker-hose irrigation systems (see pp.64-65) rather than overhead sprinklers. 

The microirrigation method known as drip irrigation delivers water through long, narrow strips of punctured plastic tubing. These farmers are placing tubing in a soon-to-be-planted field. Once installed, the system will provide only as much water as the plants need. 

There are three potential solutions for annual and perennial weed problems with drip irrigation. One is the use of preemergence herbicides that have residual weed control properties, particularly under continuous moisture. Another is the use of contact herbicides on the emerged weeds in the wet spot or persistent herbicides with contact activity. A third approach is the use of herbicides through the drip system when allowed by the product label (i.e., the use of herbicides capable of killing weeds as they germinate). With all three approaches it is essential that perennial weeds... 

The low levels of rainfall in south-central Washington make irrigation a necessity. Rill, solid-set overhead sprinkler, drip, and center-pivot irrigation systems are all being used to some extent in the vineyards of the Northwest. 

Don t use sprinklers automatic irrigation systems, such as sub-soil drip pipes that allow water to drip into the soil, make great alternatives to sprinklers, and use far less water. They are especially useful for times when you are out of town. 

Irrigation systems are categorized as flooding, soil surface spraying or sprinkling, and drip irrigation, which are all referred to in detail in the following ... 

Potable water (as distinct from seawater) has become a valuable commodity which is generally used in homes and industry that include irrigation. It has recently been shown that over 70% of fresh water is usually used to irrigate our food sources. Much of this water is supplied by either surface drip or sprays as well as by subsurface drip. All such sources require appropriate knowledge of the plants requirements as well as rainwater deliveries. The water on demand plant watering system using the microporous hydrophilic membranes was developed by Dr. Lue Errede at 3M in Minnesota. 

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