TOP LAYER PROPERTIES FOR PLAYABILITY OF GRASS FOOTBALL FIELDS: SAMPLING STRATEGY

摘要

As no general agreement exists about the number of soil samples to be taken on a football fieldto obtain a statistically reliable value of a soil physical or soil mechanical characteristic, a studywas carried out on 77 undisturbed soil samples from the top 5cm layer of a football field ofGhent University, Belgium. Another 77 disturbed soil samples were taken at the same spots butat a depth of 5-10 cm. Soil characteristics determined were: the particle size distribution (texture), organic matter content, moisture content at time of sampling, bulk density, total porevolume, moisture content at field capacity and at wilting point, available water percentage, freedrainage (%), penetration resistance determined with 4 different probes. It was found that with a small number of samples the highest level of accuracy was obtained when determining sand content and the density. Moisture content and especially the penetration resistance determination required a large number of samples. With exception for the penetration resistance, 7 samples taken at spots in extensively played areas were sufficient to obtain more than 80% level of accuracy for the other soil characteristics.