. . . "Fotochemick\u00E9 zm\u011Bny speciace kov\u016F a fosforu v p\u0159\u00EDrodn\u00EDch vod\u00E1ch" . "We propose a research on the poorly understood impact of photochemical transformation of allochthonous dissolved organic matter on in-lake biogeochemical cycles of Al, Fe, and P. What are the reaction products and kinetics of these processes? How important are they in the fresh-water cycling of metals and P? This proposal defines a program of research to answer these not-yet-addressed questions. The answers are very important (as shown by preliminary research) for understanding controls of metal speciation and toxicity in lakes, metal transport to sediments, and bioavailability of phosphorus, the most limiting nutrient in temperate lakes. We hypothesize that: H1: Dissolved organic carbon exported from acidic forest soils contains a substantial portion of weakly bound metals that can be rapidly photo-liberated in surface waters. H2: Photo-liberated Al and Fe, and structurally and quantitatively changed organic carbon form new complexes that include and immobilize P. H3: Aluminum can replace Fe"@en . . "2009-10-22+02:00"^^ . . . "9"^^ . " organic carbon" . "2008-04-25+02:00"^^ . "9"^^ . "http://www.isvav.cz/projectDetail.do?rowId=GA206/06/0410"^^ . . . "2006-01-01+01:00"^^ . . "V hlavn\u00EDch c\u00EDlech projektu %22Fotochemick\u00E9 zm\u011Bny speciace kov\u016F a fosforu v p\u0159\u00EDrodn\u00EDch vod\u00E1ch%22 bylo dosa\u017Eeno n\u00E1sleduj\u00EDc\u00EDch v\u00FDsledk\u016F: (1) Laboratorn\u00ED pokusy prok\u00E1zaly siln\u00FD vliv fotochemick\u00E9 degradace DOC na jeho struktur\u00E1ln\u00ED, komplexotvorn\u00E9 a fluorescen\u010Dn\u00ED"@cs . "Photochemical transformation of metal and phosphorus species in natural waters"@en . "1"^^ . . "2"^^ . "GA206/06/0410" . . "Major results of the project (Photochemical transformation of metal and phosphorus species in natural waters) are as follows: (1) Laboratory experiments showed a strong effect of photochemical degradation of DOC on its structure, aromaticity, fluorescenc"@en . "0"^^ . "phosphorus" . . . . . "Navrhujeme detailn\u00ED v\u00FDzkum vlivu fotochemick\u00FDch zm\u011Bn rozpu\u0161t\u011Bn\u00FDch organick\u00FDch l\u00E1tek z terestrick\u00FDch zdroj\u016F na biochemick\u00E9 cykly Al, Fe a P v povrchov\u00FDch vod\u00E1ch. Jak\u00E9 jsou reak\u010Dn\u00ED produkty a kinetika t\u011Bchto proces\u016F? Jak d\u016Fle\u017Eitou roli hraj\u00ED ve sladkovodn\u00EDch cyklech kov\u016F a fosforu? Navr\u017Een\u00FD projekt p\u0159edkl\u00E1d\u00E1 v\u00FDzkumn\u00FD program s c\u00EDlem zodpov\u011Bd\u011Bt tyto dosud ne\u0159e\u0161en\u00E9 nov\u00E9 ot\u00E1zky. Odpov\u011Bdi na n\u011B jsou d\u016Fle\u017Eit\u00E9 (jak nazna\u010Duj\u00ED p\u0159edb\u011B\u017En\u00E9 v\u00FDsledky) pro pochopen\u00ED proces\u016F zodpov\u011Bdn\u00FDch za speciaci a toxicitu kov\u016F v povrchov\u00FDch vod\u00E1ch, jejich transport do sediment\u016F a biologickou dostupnost P, tj. \u017Eiviny prim\u00E1rn\u011B limituj\u00EDc\u00ED produktivitu sladkovodn\u00EDch ekosyst\u00E9m\u016F. Na\u0161e hypot\u00E9zy jsou: H1: Rozpu\u0161t\u011Bn\u00FD organick\u00FD uhl\u00EDk (DOC) exportovan\u00FD z kysel\u00FDch lesn\u00EDch p\u016Fd obsahuje v\u00FDznamn\u00E9 mno\u017Estv\u00ED slab\u011B v\u00E1zan\u00FDch kov\u016F, kter\u00E9 se mohou v povrchov\u00FDch vod\u00E1ch uvolnit fotochemick\u00FDmi reakcemi. H2: Fotochemicky uvoln\u011Bn\u00FD Al a Fe a kvalitativn\u011B a kvantitativn\u011B zm\u011Bn\u011Bn\u00FD DOC tvo\u0159\u00ED nov\u00E9 komplexy, kter\u00E9 zahrnuj\u00ED a imobilizuj\u00ED P. H3:" . . . . " iron" . "phosphorus; aluminum; iron; organic carbon; photochemistry"@en . . " aluminum" . "2008-12-31+01:00"^^ . .