The effect of pH, ionic strength, and cation in solution on the binding of phenanthrene by a soil humic acid in the aqueous phase was determined using fluorescence quenching. The phenanthrene binding coefficient with the dissolved soil humic, Koc, decreased with increasing ionic strength and solution cation valence. At low values of ionic strength, Koc values for this soil humic acid increased ...

Increasingly, products containing humic substances are appearing in the turf industry market claiming to reduce water and fertilizer use by increasing soil moisture and nutrient availability. Humic acid is the most common humic substance that has been studied, but results have been highly variable (Cooper et al.; 1998).The response of humic acid is difficult to interpret due to confounding effe...

Humic substances are routinely applied to creeping bentgrass putting greens during times of stress to improve turf health. Confounding effects of added nutrients and other ingredients make it difficult to separate the effects caused by the organic material from additional effects of the supplemental ingredients. Claims made in advertising and marketing of the effectiveness of humic substance pr...

To evaluate which microorganisms might be responsible for microbial reduction of humic substances in sedimentary environments, humic-reducing bacteria were isolated from a variety of sediment types. These included lake sediments, pristine and contaminated wetland sediments, and marine sediments. In each of the sediment types, all of the humic reducers recovered with acetate as the electron dono...

Pulsed column experiments using Co, fulvic acid and porous sediment packing, along with up/down-flooding experiments using Eu, humic acid and intact sandstone blocks have been performed. The elution of metal and humic and their distribution along the sandstone columns have been measured. A mixed equilibrium and kinetic coupled chemical transport model has been used to simulate the results. In b...

In this study, the ultrafiltration membrane for humic substance removal was prepared by blending polysulfone with a high concentration of PEG400 as additives. The influences of the additive to the fouling resistance capability and humic substances rejection of the polysulfone membrane were investigated. The addition of 35%wt of PEG400 concentration improved the pure water flux up to 200, but re...

humic acid as an organic substance can bound heavy metals. it is a best way of decreasing the hazardous effect of heavy metals on plants and thereby on humans. a factorial experiment was conducted in a completely randomized design of seven replications. the treatments consisted of three cadmium levels (0, 2 and 4 mgl-1), and three humic acid levels (0, 100, 1000 mgl-1) added to nutrient solutio...

We discuss the problems with and the real possibilities of determining oil pollution in situ in coastal marine waters with fluorescence spectroscopy and of using artificial neural networks for data interpretation. In general, the fluorescence bands of oil and aquatic humic substance overlap. At oil concentrations in water from a few to tens of micrograms per liter, the intensity of oil fluoresc...

Many studies tested different feed additives, among these additives, humic substances (HS) have been used in livestock and poultry diets. Humic substances commonly present in nature as they are created from the organic matter decomposition, and are normally found in the soil and natural water. Active components of HS consist of humic acid (HA), humus, ulmic acid, fulvic acid, humin and certain ...

to study the effects of mycorrhiza fungi and humic substances on yield and yield components of corn (zea mays l. var. s.c. 704) under limited irrigation condition, an experiment was conducted in split plot arrangement based on rcbd in four replications at the research farm of university of tehran (karaj-iran) in 2011. the main factor consisted of three irrigation levels i.e. normal (irrigation ...