Bacterial decomposition of vascular plant detritus in coastal wetlands results in the conversion of particulate organic matter to dissolved form and causes the release of humic substances into the bulk dissolved organic carbon (DOC) pool. WC found that 34% of the DOC accumulating during degradation of salt marsh grass (Spartina alternif7oru) from coastal wetlands of the southeastern U.S. fits t...

Huniic substances (fulvic and humic acids) are the decomposition products of plant material and constitute a major part of the earth's organic carbon [ 11. Their presence in aquatic ecosystems is important because of their binding capacity for protons. metal ions (geocycling) and organic micropollutants such as pesticides and herbicides [2]. The characterisation of humic substances in ternis of...

The Windermere humic aqueous model (WHAM) initially designed to model metal cation binding on humic substances were applied in predictive ecotoxicology [2]. For terrestrial higher plants, a recent investigation showed that WHAM was able to satisfactorily model cadmium (Cd), nickel (Ni), and zinc (Zn) concentrations in pea (Pisum sativum L.) roots, but that it overestimated the Cu concentration ...

The Paenibacillus sp. strain PAMC 26794 was isolated from the tundra grasslands in Alaska for its high ability to degrade humic acids. We sequenced the PAMC 26794 genome to discover the degradative genes for natural humic substances and we propose the degradation pathway(s) of an abundant bacterial group (genus Paenibacillus) that inhabits cold environments.

The effect of humic substances from different sources on the performance and selected biochemical indicators was studied in 150 one-day-old broiler chickens (Ross 308) divided into control (C) and two tested groups (n = 50). Chickens of tested groups were fed diets supplemented with natural humic compounds (group HS) and sodium humate (group HNa) at amounts of 5 g·kg-1 of feeds in phase 1 and 7...

Plug-flow biofilm reactors colonized by microorganisms in streamwater were used to measure the concentration and composition of biodegradable dissolved organic C (BDOC) in White Clay Creek. During the 4-month study period, DOC ranged from 0.8 to 10.4 mg C liter-’ and was, on average, composed of 75% humic substances, 13% carbohydrates, 2% amino acids, and 18% > 100 kDa. The carbohydrates were p...

Analytical pyrolysis is a technique currently used for investigating structural features of complex macromolecular materials. However, pitfalls appear to be widespread in pyrolysis studies of humic substances, and serious limitations can be experienced during the analytical procedure due to thermal reactions and configuration of the pyrolysis units and chromatographic systems. Pyrolysis present...

The study aimed at evaluating the humic substances (HSs) content from municipal solid waste incinerator (MSWI) bottom ash and its variation with time and the effect of temperature on HSs formation. The process suggested by IHSS was applied to extract HSs from two different bottom ash samples, and the extracted efficiency with NaOH and Na4P2O7 was compared. MSWI bottom ash samples were incubated...

Humic substances, such as those listed in the above title, play a vital role in soil fertility and plant nutrition. Plants grown on soils which contain adequate humin, humic adds (HAs), and fulvic adds (FAs) are less subject to stress, are healthier, produce higher yields; and the nutritional quality of harvested foods and feeds are superior. The value of humic substances in soil fertility and ...