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Investigation on release of nitrogen and phosphorus from the sediments of different depth in Lake Suwa [Japan]
1987
Kono, Y. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Terasawa, J. | Harada, T. | Nasu, Y. | Kugimoto, M.
For the purpose of determining the effect of dredging on nutrients releasing from the sediment at the bottom of Lake Suwa after some of its sediment has been dredged, an experiment was performed to find out how much ammonium and phosphate would release from different depths of the sediment. Lake Suwa's sediment contains a lot of nitrogen and phoshorus down to its lower layers. The results of the experiment were as follows: The speed at which ammonium released from was faster as the depth of sediment increased. The speed at which ammonium was generated in the sediment showed the highest of 2.58N micro g/g dry sediment d in a 0-10cm layer. However, ammonium showed a generation speed of 1.3-1.4N micro g/g dry sediment-d at the depth of 10cm and more, indicating that ammonium easy to release from is generated even in lower layers. The speed at which phosphorus released from was 1.3-1.7Pmg/square m d in a 0-20cm deep layer, and 0.14-0.31Pmg/square m d at the depth of 20cm and more. The speed of Phosphorus releasing from lower layers of the sediment decreased to 1/4-1/10 of that in upper layers, and it was indicated that very little phosphorus flows out of the sediment at the depth of 20cm and more.
Show more [+] Less [-]Eutrophication in lakes and the trophic state index
1981
Kawamura, M. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Higuchi, S.
The analytical method for chlorophyll degradation products in sediment and an investigation of Lake Suwa [Nagano, Japan]
1981
Seki, H. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Akaoka, T. | Kono, Y. | Ogihara, K.
The release of phosphate from the sediment in Lake Suwa [Nagano, Japan]: The comparison of the release between the surface sediment and lower one
1981
Kono, Y. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Katsuno, T. | Nagase, K.
Evaluation of the eutrophication in precipitation based on an algal assay procedure
1981
Sasaki, K. (Nagano-ken. Research Inst. for Health and Pollution (Japan))
