Soil water repellency causes at least temporal changes in the hydrological properties of a soil which result in, among other things, suboptimal growing conditions and increased irrigation requirements. Water repellency in soil is more widespread than previously thought and has been identified in many soil types under a wide array of climatic conditions worldwide. Consequences of soil water repellency include loss of wettability, increased runoff and preferential flow, reduced access to water for plants, reduced irrigation efficiency, increased requirement for water and other inputs, and increased potential for non-point source pollution. Research indicates that certain soil surfactants can be used to manage soil water repellency by modifying the flow dynamics of water and restoring soil wettability. This results in improved hydrological behavior of those soils. Consequently, the plant growth environment is also improved and significant water conservation is possible through more efficient functioning of the soil. Vodoodpudivosť pôdy spôsobuje prinajmenšom dočasné zmeny v hydrologických vlastnostiach pôdy, ktoré okrem iného môžu viesť k suboptimálnym podmienkam rastu rastlín a k zvýšenej potrebe závlah. Vodoodpudivosť pôdy je rozšírenejší jav, ako sa pôvodne predpokladalo; bola identifikovaná v mnohých pôdnych typoch a klimatických podmienkach na celom svete. Dôsledkom vodoodpudivosti pôdy je strata zmáčavosti, zvýšený povrchový odtok a preferenčné prúdenie, znížená dostupnosť vody a iných vstupov pre rastliny, znížený účinok závlah, zvýšené požiadavky na vodu a iné vstupy, ako aj zvýšené riziko plošného znečistenia. Výskum naznačuje, že niektoré povrchovo aktívne látky (soil surfactants) môžu upraviť vodoodpudivosť pôdy obnovením omáčania a modifikáciou dynamiky vody. Výsledkom je zlepšenie hydrologických vlastností pôdy. Podobne, výsledkom je zlepšenie prostredia pre rast rastlín, zvýšenie retencie vody v pôde a teda aj efektívnejšia funkcia pôdy.KĽÚČOVÉ SLOVÁ: vodoodpudivosť pôdy, efektívnosť závlahy, povrchovo aktívne látky, preferované prúdenie, retencia pôdy.

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Alkyl phenol ethoxylate (APE) surfactants are used in horticultural substrates but are considered nonbiodegradable, whereas others such as alkyl polyglucoside (APG) are derived from biodegradable sugar compounds. APE reduced total porosity (TP), container capacity (CC), and aeration porosity (AP) whereas APG with polyalkylene oxide block copolymer surfactant (APG/BLK) increased TP, CC, and AP for some substrates but other substrates remained unaffected by either surfactant. We determined substrate leaching fraction (LF) and wettability rating (WR) after drenches of 0.003 to 0.2 mL·L−1 APG/BLK for six bark substrates for three wetting cycles. After the third wetting cycle, five substrates had reduced LF and increased WR. Drenches of 0.2 mL·L−1 APE or APG/BLK for three wetting cycles indicated that APE was more efficacious than APG/BLK for reducing LF or increasing WR. APE was determined to be an effective surfactant for difficult-to-wet substrates, but drenching sometimes reduced TP. No reductions in TP were noted when using APG/BLK. Drenching rates of 0.003–0.2 mL·L−1 APG/BLK for three successive wetting cycles reduced LF and increased WR for most substrates, indicating potential usage for some horticultural applications.

Recommendations for golf course green construction have been for rootzone mixes with at least 90% sand while the remainder is typically peat or other organic material. This type of construction mix initially facilitates water movement through the profile but provides an environment conducive to soil hydrophobicity. Several factors such as sand texture, frequent wet to dry cycles, and accumulation of organic matter and thatch contribute to the development of soil water repellency in golf course greens. In research studies conducted over the past fifteen years in several locations across the United States, water drop penetration tests (WDPT) on golf greens have shown slightly and strongly water repellent soil is prevalently found at 0 and 1 cm depths. In the majority of locations, as the depth of profile increased, soil hydrophobicity decreased and was mostly non‐existent at the 6 cm depth. These results suggest that despite soil texture and management practices, soil hydrophobicity in a managed turfgrass area is most severe in the thatch and mat area of the profile. While the knowledge of what contributes to water repellency is critical for alleviating symptoms associated with hydrophobic coatings, management practices may be more successful if the focus was on the depth of the repellency.