Studies on microbiological remediation in closed bay
Grant-in-Aid for Scientific Research (C)
|Allocation Type||Single-year Grants|
|Research Institution||Mie University|
SUGAHARA Isao Mie University, Faculty of Bioresources, Professor, 生物資源学部, 教授 (80024826)
KIMURA Toshio Mie University, Faculty of Bioresources, Research Assistant, 生物資源学部, 助手 (50024831)
|Project Period (FY)
1995 – 1997
Completed(Fiscal Year 1997)
|Budget Amount *help
¥2,200,000 (Direct Cost : ¥2,200,000)
Fiscal Year 1997 : ¥600,000 (Direct Cost : ¥600,000)
Fiscal Year 1996 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 1995 : ¥1,100,000 (Direct Cost : ¥1,100,000)
|Keywords||bioremediation / microbial function / environment inprovement / dnitrification / closed bay / 微生物開発・利用 / バイオリメデイエーション / バイオリメティエーション|
1.In order to improve coastal environment (closed bay etc.), it is necessary to decrease in organic matter level and inorganic nutrients (nitrogen or phosphorus) level. In this study, we set up microbial system containing denitrifying bacteria, ammonia-oxidizing bacteria and micro-algae. All microorganisms were tried to isolate from polleted bottom mud.
2.The optimum temperature and pH for denitrification activity of immobilized denitrifying bacteria strain Sc51 were 30ﾟC and pH7-8, respectively. The maximum denitrifying activity (Vmax) of strain C8-2 was 3.74 mumol/hr, and NO_3^- affinity of denitrifying activity was 40.0mumol/l.
The discharged water from waste treatment facility was treated with denitrifying bacteria strain Sc51. Strain Sc51 effectively removed nitrate and/or nitrite. The eliminating activity was 55 mumol/hr.
Useful micro-algae strains capable of strongly producing oxygen under low light condition, and weakly cosuming oxygen under dark condition were selected. The addit
ion of microalgae strain P-1 to mixture of in situ seawater and bottom mud was able to improve oxygen poor environment.
An attempt to utilize useful marine microorganisms was carried out for the improving polleted environment. Ceramic grains with high porosity (porous beads) were used as microbial carrier. Denitrifying bacteria were attached on and into the beads. Ammonia-oxidizing bacteria mixpopulation and micro-algae were also attached on the surface of the beads. The beads prepared were spread on the bottom mud of polluted closed bay on January and July. The results obtained were as follows :
a)The beads recovered from the bottom mud contained denitrifying bacteria and ammonia-oxidizing bacteria.
b)When several types of bacterial numbers in bottom mud were compared, no significant difference could be obseved
c)The organic matter content and total nitrogen content of bottom mud markedly decreased after the beads spread.
d)The in situ eliminating activities of organic matter and nirtrogen were high in summer. However, about 1/2-1/3 of the summer activities were observed in winter.
6.Environment improvement or control by useful microbial functions will be expected to practical use in the fields of fisheries and environmental science. Less
Research Output (17results)