スサビノリPorphyra yezoensis葉体のアンモニア態および硝酸態窒素の取り込みに及ぼす温度の影響

Effects of temperature on the uptake kinetics of ammonia-N and nitrate-N by Porphyra yezoensis thalli.

Yamamoto Tamiji

Takao Masahide

藻類

The uptake kinetics for ammonia-N and nitrate-N by Porphyra yezoensis thalli were examined under various temperatures (4-18°C). The carbon and nitrogen contents of the frond were 341.9±24.8 and 52.5±10.4 mg•g dry wt-1, respectively, and the C/N ratio was 6.80±1.58. The uptake parameter, Ks, for ammonia-N varied from 48.3 to 182.7 µgN•l-1, and Vm was from 0.0033 to 0.0082 h-1. The Ks for nitrate-N varied from 10.1 to 53.9 µgN•l-1, and the Vm was from 0.0005 to 0.0013 h-1. These parameters both for ammonia-N and nitrate-N showed the maxima at 14°C. Comparing the Vm of ammonia-N with that of nitrate-N under the same temperature, ammonia-N was taken 6.3-9.4 times faster than nitrate-N by the frond. These parameters expressed in common logarithms were converted by the quadratic equations to absolute temperatures; for ammonia-N, VA=S × 10-29.642(103/T)2+206.93(103/T)-363.23/(S+10-39.556(103/T)2+ 276.17(103/ T)-479.77) and for nitrate-N, VN = S × 10-32.464(103/T)2+227.45(103/T)-401.36/(S+10-37.051(103/T)2+257.50(103/T)-445.69). These equations consisting of the major factors such as ammonia-N and nitrate-N concentrations and temperature which are controlling the growth of Nori frond are considered to be useful in estimating the production capacity of Nori cultural ground.

ammonia

nitrate

Porphyra

temperature

uptake

Botany [ 470 ]

jpn

日本藻類学会

[ISSN] 0038-1578

[NCID] AN00134842