because ΔDO D ¼ À1.26 and δDO D ¼ 0.60, these values may be substituted for
expressions (6.6), (6.7), and (6.4), and R, Pn, and P can be calculated as follows:
R ¼ À2 Â ΔDO D À δDO D
ð
Þ ¼ À 2 Â À1:26 À 0:60
ð
Þ¼3:72 mg=L=day
Pn ¼ ΔDO L À δDO L ¼ 1:34 À À1:86
ð
Þ¼3:2 mg=L=day
P ¼ Pn þ 1=2
ð
ÞR ¼ 3:2 þ 3:72 Â 1=2
ð
Þ ¼ 5:06 mg=L=day
6.3 Endpoint of the Microcosm N-System
It may be said that the endpoint of the toxicity test in the environmental impact
assessment is an index for expressing the negative influence that a chemical substance generally has on an organism. The endpoints of this assessment using the
microcosm N-system are production (P) and respiration (R), which allow for the
influence of chemical substances (i.e., test materials) to be easily and appropriately
determined. The biomass or chlorophyll a or b are measured secondarily and not as
endpoints. Namely, a functional parameter (i.e., P, R, or P/R ratio) is defined as the
Fig. 6.1 Enter data to MS Excel sheet
50
K. Kakazu et al.
expressions (6.6), (6.7), and (6.4), and R, Pn, and P can be calculated as follows:
R ¼ À2 Â ΔDO D À δDO D
ð
Þ ¼ À 2 Â À1:26 À 0:60
ð
Þ¼3:72 mg=L=day
Pn ¼ ΔDO L À δDO L ¼ 1:34 À À1:86
ð
Þ¼3:2 mg=L=day
P ¼ Pn þ 1=2
ð
ÞR ¼ 3:2 þ 3:72 Â 1=2
ð
Þ ¼ 5:06 mg=L=day
6.3 Endpoint of the Microcosm N-System
It may be said that the endpoint of the toxicity test in the environmental impact
assessment is an index for expressing the negative influence that a chemical substance generally has on an organism. The endpoints of this assessment using the
microcosm N-system are production (P) and respiration (R), which allow for the
influence of chemical substances (i.e., test materials) to be easily and appropriately
determined. The biomass or chlorophyll a or b are measured secondarily and not as
endpoints. Namely, a functional parameter (i.e., P, R, or P/R ratio) is defined as the
Fig. 6.1 Enter data to MS Excel sheet
50
K. Kakazu et al.