Microbiological Sources of Ammonia in Freshwater Lake Sediments

Abstract

During summer stratification ammonia is released from the profundal sediments of Blelham Tarn (English Lake District). The quantity of ammonia released exceeds the consumption of nitrate in the hypolimnion. Nitrate dissimilation may be a component in the generation of ammonia, but only during early summer when nitrate is still available. The remainder of the ammonia arises largely from the deamination of proteins, amino acids and urea. Population estimates of bacteria which produced ammonia from nitrate, amino acids and urea were of the same order of magnitude. Numbers of bacteria which produced ammonia from nitrate increased with sediment depth, and urea decomposers were more numerous in the profundal (deep water) sediments. While nitrate was available in the water column, surface sediments converted nitrate almost exclusively to nitrogen gas. After depletion of the nitrate, the release of ammonia from washed sediment particles was largely microbiological, whereas there was a significant chemical component to the release from intact sediment cores. Chemical binding of ammonia by the sediments was demonstrated and this hindered calculations of inorganic nitrogen metabolism based on changes in water chemistry. Trace additions of l4C-labe1led protein, amino acids and urea to sediments showed that urea was turned over the most rapidly, but more reliable estimates of available protein in the sediments are required before decomposition rates can be treated with confidence.

Sediment bacteria and archaea community analysis and nutrient fluxes in a sub-tropical polymictic reservoir

“…Decomposition of phytoplankton in the sediments generates ammonia primarily from the deamination of amino acids and urea (Jones et al 1982). Ammonia is converted to nitrate in a 2-step process termed 'nitrification', which is performed by 2 distinct groups of aerobic chemolithoautotrophic microbes.…”

The Chemistry of Phosphate and Nitrogen Compounds in Sediments

“…They showed that half the org-N arriving at the lake bottom was released as NH + 4 and the other half accumulated as org-N sed , but some more experimental data are needed to obtain a complete picture. Further studies by Jones et al (1982) showed a long turn-over time for added proteins, a shorter one for amino acids and a still shorter one for urea. Jones & Simon (1980 and Jones et al (1982) examined the release of NH + 4 in the sediment of Blelham Tarn (Lake District, UK), paying attention to the turn-over rate of org-N.…”

“…Jones & Simon (1980 and Jones et al (1982) examined the release of NH + 4 in the sediment of Blelham Tarn (Lake District, UK), paying attention to the turn-over rate of org-N. Jones et al (1982) argued that estimates of available protein are required before the decomposition rate can be truly estimated. Accounting for the relative surface areas of the profundal and littoral sediment, methanogenesis and SO 2− 4 reduction were more important in the former ones, while NO − 3 reduction and aerobic respiration were greater in the littoral zone.…”

Seasonal and spatial distribution pattern of nitrogen fixing bacteria in fish ponds under different management systems

“…Although there has been a great deal of interest in the study of nitrogen fixing microorganisms in temperate waters (Brezonik, 1972;Keeney, 1973;Stewart, 1975;Stewart et al, 1977;Dierbey & Brezonik, 1981;Jones et al, 1982;Allen et al, 1983), nitrogen fixation has seldom been measured in tropical water bodies, especially in fish farming ponds where the nitrogen input differs depending upon the management systems. In the present investigation, we examined spatial and seasonal distribution patterns of heterotrophic nitrogen fixing bacteria in six ponds farmed as monoculture, polyculture, and traditional systems.…”