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<br />USE OF SALINE DRAINAGE WATER FOR IRRIGATION
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<br />TABLE 6
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<br />Yields of crops in "block" rotation
<br />
<br />Treatment I
<br />
<br />Crop/Year
<br />Cotton/]982' Cotton/]983' Wheat/19843 Alfalfa/]985'
<br />1.47(0.04)' 1.15(0.06) 7.7(0.]) ]7.5(0.9)
<br />1.48(0.03) 1.12(0.05) 7.7(0.]) ]5.7(1.1)
<br />1.55(0.02) 0.74(0.03) 7.6(0.1) ]6.6(0.7)
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<br />Ie = Colorado River water used solely for irrigation; A = Alamo River water used solely for irriga-
<br />tion; cA = Alamo River water used for irrigation after seedling establishment with Colorado River
<br />water for cotton. Wheat and alfalfa irrigated only with Colorado River water.
<br />2Commercial yield of lint, tons per hectare.
<br />3Tons of grain per hectare.
<br />'Tons of dry hay per hectare.
<br />sValue in parentheses is standard error of mean; six replicates.
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<br />Fig. 1. Levels of sOif'aa1inity within the root zone following cotton and during the wheat and alfalfa
<br />production periods 6f the Hblock" rotation.
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<br />alfalfa hay occurred in the "block" rotation associated with the previous use
<br />of drainage water on these same lands, under these conditions in which the
<br />wheat and alfalfa crops were irrigated with Colorado River water.
<br />Crop quality was never inferior and often was superior, when the crops were
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