zone. The general trend was a decrease in salinity from the upper to 
lower zone, regardless of depth. 
In the upper zone,a decrease in salinity occurred with depth 
(Table 10). In contrast, soil salinity increased slightly from the 
surface to the 6-inch depth in both the middle and lower zones. Water 
salinity in May ranged from 3,200 to 8,000 ppm between blocks. 
Soil salinity in Block I, disregarding depth and zone, was lower 
(4,509 ppm) than in the other blocks in February (Table 11). The 
highest salinity was in Block IV, the protected ditch. By May, soil 
salinity had increased in all blocks with Blocks II and IV the lowest 
and Block I the highest (9,485 ppm). These data indicate a variation 
not only within blocks, but also between dates. For example, Block I 
had the lowest salinity in February and the highest in May while Block 
IV had the lowest in May and the highest in February. 
Soil salinity was considerably higher on both dates than water 
salinity. Following the relatively dry month of April, both soil and 
water salinity values were higher than during February. This indicates 
that following below normal precipitation both soil and water salinities 
increase and could present a problem in vegetation establishment, par- 
ticularly of the less tolerant plant species. 
3. Soil pH and Extractable Cations. 
Data on soil pH and extractable cations were collected in February 
and May 1974 (Tables 8 and 9). Two collection dates provided data 
for comparison of values over time of these normally stable soil 
characteristics. 
In February, disregarding study blocks and zones, soil pH decreased 
slightly with increasing depth (Table 12). The range was narrow, 
fluctuating around a neutral pH. When soil depth and blocks were dis- 
regarded, soil pH increased slightly from the upper zone to the lower 
zone (Table 13). Again the mean pH values were near neutral. 
Extractable cations, calcium (Ca), potassium (K), magnesium (Mg), 
and sodium (Na) in February fluctuated in quantity with changes in soil 
depth and between zones (Tables 12 and 13). However, there was no 
significant difference between study blocks. 
Maximum Ca concentration was in the surface 2 inches of soil with 
a decrease in the 2- to 4-inch layer. A corresponding increase was 
recorded in the 4- to 6-inch layer. In contrast, K increased in con- 
centration from the soil surface to 6 inches. Both Ca and K occurred 
in similar quantities, but Mg occurred in larger quantities. The trend 
was a decrease in Mg concentration from the soil surface to 4 inches and 
an increase to the maximum in the 4- to 6-inch layer. Sodium concentra- 
tion was high, regardless of soil depth. The range was from a low of 
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