Response of Main Soil Hydrological Properties to Measuring Techniques and Organic Matter Types and Levels.
Ali Fares1, Farhat Abbas2, Mohammad Safeeq1, Amjad Ahmad1, and Jonathan Deenik2. (1) University of Hawaii at Manoa, Dept of Natural Res and Envi. Management, 1910 East West Road, Honolulu, HI 96822, (2) NREM, University of Hawaii, 1910 East West Road, Honolulu, HI 96822
Organic matter (OM) affects several soil hydrological properties i.e. infiltration rate, (q) saturated hydraulic conductivity (Ksat). The objectives of this study were 1) to study the effect of OM types (chicken, dairy and swine manures) and levels (168, 336, and 672 kg/ha equivalent Nitrogen) on q and Ksat; 2) to quantify the effect of measuring instruments on Ksat. Steady state infiltration rates were measured using tension infiltrometer (TI) and double ring infiltrometer (DR) to calculate Ksat. Statistical analysis showed that Ksat values measured with DR were 1.14 to 2.19 times larger than those measured with TI at lower levels of applications whereas; the values calculated from TI were 1.07 to 1.24 times greater at higher levels of applications. For both techniques, the calculated Ksat increased with increase in OM contents for chicken manure (CM) and dairy manure (DM) treatments. However, the opposite occurred for swine manure (SM) treatment where Ksat decreased as SM level increased. The effect of OM level was not significant in SM treatment.