SportsTurf provides current, practical and technical content on issues relevant to sports turf managers, including facilities managers. Most readers are athletic field managers from the professional level through parks and recreation, universities.
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14 SportsTurf | September 2016 www.sportsturfonline.com Phosphorus. Similar to the cations, P availability in the sands treated with paint was comparable to the control for the fi rst three months. However, in months four and fi ve, P levels generally exceeded those in the untreated control. The P level found in sand treated with PSR #2 in month four was higher than the other two treatments. In month fi ve, the acrylic and PSR #2 measurements were 12.6 ppm and 14.8 ppm and the PSR #1 was 0.7 ppm (data not shown). Sulfur. Like P, the release of S from the treated sands began in month four. There were no differences in extracted S among paint treatments for four out of the six months of the experiment. There was a difference in the S levels in the fourth month between sand treated with PSR #2 measuring 374.2 ppm compared to sand treated with PSR #1 and acrylic with 209.6 ppm and 167.8 ppm respectively. In the sixth month, PSR #2 was also higher than PSR #1 and acrylic (data not shown). Saturated Hydraulic Conductivity. The Ks results are measured in centimeters per second (cm/sec). Each treatment was adjusted for the control by corresponding dates. The values show a range from -0.01 to 0.04 cm/sec. When a value is negative, the movement of water through the profi le is slower in the paint treatment than it was in the untreated control. When a value is positive, the movement of water through the profi le is faster in the paint treatment than it was in the untreated control. The Ks values (Figure 3) demonstrate a trend just opposite of the chemical variables. There were no differences in Ks among paint treatments for fi ve of the six months of the experiment. In the second month, sand treated with acrylic paint and with PSR #1 were both faster than the sand treated with PSR #2. The average Ks in sand treated with acrylic paint and PSR #1 was 0.04 cm/sec and 0.04 cm/sec respectively compared to PSR #2 at 0.02 cm/sec. Saturated hydraulic conductivity levels did vary by month. Rates were accelerated in months one and two. By month three and four, the Ks began to decrease but it was still faster than the untreated control. This is the opposite result of what was expected. It was anticipated that the presence of paint would slow infi ltration. It is likely that the paint coated the sand particles and this coating repelled water resulting in an FIELD SCIENCE increased Ks. By the fi fth month, the paint had degraded to the point where Ks was similar to the untreated control. CONCLUSIONS The paint evidently coated the sand particles, thereby reducing CEC and the release of cations for the fi rst four months of the experiment. By the fi fth month, the paint had degraded to the extent that CEC sites were exposed and cations were released into the soil solution. The anions, P and S, showed an increase by month four, thirty days before the cations were released. The reason for this is unclear, although it may be due to other unknown components in the paints. This is also the case for Ks. The acrylic paint does appear to speed up water movement, followed by PSR #1 and then PSR #2. In all paint treatments, the fi rst three months the Ks is quicker than the untreated control. By the fourth month, the paint begins to degrade and as a result the Ks gets slower. Then in the fi fth month, all treatments are slower than the untreated control. This substantiates the hypothesis that the paint was coating the sand particles and degraded over a four to fi ve month period. It cannot be determined from the chemical or physical results that one of the paints broke down quicker than the other two. The paints did affect each treatment, but it took six months for each of them to break down chemically. The same is true for the Ks results. Although the PSR #2 had less of an effect on the Ks over the fi rst four months, the difference between the three treatments is very minimal. Then by month fi ve, all three treatments show no differences compared to the control. Further research on the effects of paint on the chemical and physical properties of the soil should include an expanded number of paints, including those commonly used on sports fi elds. The number of physical tests performed on the samples should also include particle size analysis (PSA) and physical performance evaluation (PE), which would include information about infi ltration rate, porosity, bulk density, particle density, and organic matter. Josh Lenz is a graduate student at Iowa State University; Nick Christians, PhD is a professor in the Department of Horticulture at Iowa State. .05 .04 .03 .02 .01 0 -.01 -.02 Ks (cm/sec) Month 0 1 2 1 2 3 4 6 5 Figure 3. Saturated hydraulic conductivity rates in the soil adjusted for the control 0=acrylic, 1=PSR#1, 2=PSR#2. Soil profile showing paint build-up Painted area at Jack Trice Stadium