Download or read book Committee for Inland Fisheries of Africa written by Food & Agriculture Organization of the United Nations and published by Food & Agriculture Org.. This book was released on 1993 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book World Population Prospects written by United Nations. Department of International Economic and Social Affairs and published by New York : United Nations. This book was released on 1986 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Water and Industry in the United States written by and published by . This book was released on 1972 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dissolved Organic Matter in Lacustrine Ecosystems written by K. Salonen and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Concentrations of dissolved organic matter (DOM) in lakes are often an order of magnitude greater than concentrations of particulate organic matter; nevertheless, the biogeochemical analysis of DOM is described in only a few textbooks on limnology (most thoroughly by Wetzel). The orgins of dissolved organic substances are largely photosynthetic; DOM is either autochthonously synthesized by littoral and pelagic flora through secretions and autolysis of cellular contents, or allochthonously generated in terrestrial systems of the drainage basin, composing largely of humic substances refractory to rapid microbial degradation. The role of DOM in lacustrine ecosystems, as energy source and system regulator, however, is still poorly known. The aim of this book is: (1) to present state-of-the-art reviews of the role of dissolved autochthonous and allochthonous organic matter in pelagial and littoral zones; and (2) to focus attention on poorly understood but critical topics and hence to provide direction for future research activity.

Download or read book Dissolved Organic Matter DOM written by Oleg S. Pokrovsky and published by . This book was released on 2017 with total page 339 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Denitrification and Its Relation to Soluble Carbon microform written by Marcia Amelia Monreal and published by National Library of Canada. This book was released on 1983 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Organic matter is necessary as a reductant in denitrification. The supply of readily decomposable organic matter or water soluble organic carbon (WSOC) provides a good index of the soil potential for denitrification. Reports in the literature indicate an important role for the water soluble organic carbon pool, however, they do not demonstrate the controls and mechanisms supplying carbon to the soluble pool. Experiments were performed in samples of Ap horizons from a Black Chernozemic soil (Malmo SiCL) and a Gray Luvisolic soil (Breton L) of the Province of Alberta, to examine some of the mechanisms supplying carbon to the water soluble pool; the relative magnitudes of assimilatory and dissimilatory NOi reduction; the relationship between changes in WSOC content of soil and NO 5 losses in saturated soils; and the effect of high NO 5 or NO 2 concentrations on denitrification. Results indicated that the WSOC contents of the Malmo and Breton soils were significantly different (at the 1% level) and that extraction of the water soluble organic carbon was described by a modified Freundlich isotherm. When air-dried soil samples were incubated at field capacity for seven days, 158 and 45 [microgramme] g[superscript -1] of WSOC were removed from the Malmo and Breton soils, respectively. Microbial immobilization of NO[subscript -3]-[superscript 15]N during 15 days under saturated conditions accounted for only 5% of the NO[subscript -3]-N losses, so that denitrification appears to be the main mechanism of [superscript 15]N losses. The greater denitrification capacity of the Malmo rather than the Breton soil was consistent with its greater supply of WSOC. Denitrification ceased in the Breton soil when WSOC content dropped below 34 [microgrammes] g[superscript -1] soil. When glucose was supplied to the Breton soil high NO[subscript -3]-N losses prevailed. This suggests that the WSOC was limiting denitrification in the Breton soil. Although extensive NO[subscript -e]-N losses occurred in the Malmo soil, these losses ceased when WSOC content dropped below 114 [microgrammes] C g[superscript -1] soil. The addition of a high dose of NO[subscript -3]-N (1500 [microgrammes] N g[superscript -1] soil) to the Malmo soil inhibited denitrification and NO[subscript -2]-N accumulated. In the Breton soil, the application of NO[subscript -3]-N plus NO[subscript -2]-N (over 300 [microgrammes] N[superscript -1] soil) inhibited denitrification as well. C/N ratios calculated with the amount of WSOC consumed per unit N denitrified confirmed expectations that a greater amount of WSOC was consumed when N was in the NO 3 -N form than when it was in the NO[subscript -2]-N form.

Download or read book Light induced Degradation of Dissolved Organic Matter in Water written by Nina Corin and published by . This book was released on 1999 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: