Vineyards irrigation

Land use in the Ebro River basin has been traditionally based on agricultural crops, such as vineyards, orchards, and maize. Up to 783,948 Ha are dedicated to agriculture, and mainly in the mid and lower Ebro sections, are irrigated. Nowadays, industry is a relevant activity at the most important cities (e.g., Zaragoza, Pamplona). Hydroelectric energy production uses about 8,297 m3/s in 340 hydroelectric plants at the Ebro River basin. Water of the Ebro River is also used for cooling nuclear and thermic plants. Urban water demand is 5% of that used for agriculture. 

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. 

Rill, or furrow irrigation, is being used less and less as new vineyards are established. The solid-set overhead sprinkler is the most widely accepted system in V. vinifera vineyards today. The newer systems are on a forty-eight by fifty-foot diamond pattern. A 9/64 orifice operating at 40-60 psig is used almost ubiquitously. An exception is the end sprinkler on the upwind edges of vineyards, where larger orifices often are used. 

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. 

In hot weather, evaporation pans lose up to one-half inch of water per day. Vineyards with cover crops lose up to 75 percent of evaporation pan losses. Up to 25 percent of the irrigation water can be lost through wind drift and evaporation. This results in a situation that is within 4 percent of a theoretical break-even input and output. To accomplish this break-even situation requires constant, twenty-four hour a day irrigation. While this concern is yet to be tested, past history with other crops has proved eminently successful. In 1978, 500 acres of V. vinifera grapes were planted under center-pivot irrigation. Since that time, an additional 1500 acres have been planted under center-pivot systems, so that today 2000 of the state s estimated 4500 acres of V. vinifera are utilizing center-pivot irrigation. 

In the past, it was considered necessary to apply thirty inches of water to a vineyard each year. Today, these requirements range as low as twenty-four to twenty-six inches per year. It has been only in the past few years that the grape growing community has begun to incorporate the data from evaporation pans, hygrothermographs, anemometers, and soil moisture measurements into its irrigation decisions. 

Figure 23 Comparison of reconstructed irrigation water tritium input (left panel), immobile vadose-zone water tritium (center panel), and measured tritium (right panel), all as a function of depth. Study site is an irrigated vineyard in the Negev Desert, Israel (source Gvirtzman and Magaritz, 1986).

The content of mobile copper form (extracted by acetate-ammonium buffer with pH 4.8) in all soil types varies from 0.05 to 0.41 ppm, being less than 1% from total content. However, it increases sharply in polluted soils of orchards and vineyards until 2.4-12.5 ppm. Some increase occurs also in rice soils, up to 0.26-0.94 ppm. It is clear that this increase is connected with application of irrigation and fungicides. The comparison of Cu content with maximum permissible levels for soils (55 ppm for total and 5 ppm for mobile forms) allowed the researchers to conclude that about 5% of agroecosystem soils are polluted by copper. 

Last week, shortly after we developed computers and landed the first man on the moon, we learnt how to clone DNA and engineer the genetic blueprint of any living cell. Only yesterday, a worldwide Internet - supported by search engines - allowed us to explore terabytes of information at the touch of a button on our newly developed laptop computers, wireless hand-held devices and smart phones. Thanks to these devices, irrigation of vineyards and the operation of large, complex wineries can now be controlled remotely by sophisticated computer networks, artificial intelligence and robotics. 

Generally, non-pressurized pipes contain carbon black (CB) as a pigment. However, CB may have a negative effect on the thermo-oxidation of polyolefins. The influence of CB on the long term thermal behavior of irrigation pipes (for vineyards in Cap Province, South Africa) based on LLDPE/LDPE recyclate is shown in Figure 21. 

While water deficit does not prevent grapes from ripening satisfactorily in terms of their sugar and acid content, excessive water delays the ripening process and alters the chemical composition of the grapes to a considerable extent. In vineyards where irrigation is used, it should be reduced to a minimum after viraison to maintain a moderate water deficit. 

Ningxia Grape production in this region started in the 1980s. The wine industry has been expanding rapidly since the 1990s of the last century. Many vineyards have been established east of Helan Mountain, a semiarid to arid area where there is usually ample water for irrigation. 

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