71
p=0.29>0.05, respectively). The vertical system to 40 cm water level was the most efficient in
COD removal, 21 g/m
2
d.
Regarding removal of total coliforms and
E. coli
, no significant difference between the mean of
the obtained data were found (p=0.133>0.05), therefore there was no incidence of different water
level applied laminar removing pathogens.
In VSSF – CW systems, Oxygen Transfer Rate (OTR) was calculated to 0 cm water level an
approximately value of 80 g/m
2
d, followed by 47 g/m
2
d was found at 40 cm water level and 45
g/m
2
d to 65 cm water level. It can be said that most vertical wetlands Oxygen Transfer Rate was
0 cm water level. The oxygen consumption rate (OCR) in wetlands was 59 g/m
2
d to 0 cm water
level, 36 g/m
2
d to 40 cm water level and 41 g/m
2
d to 65 cm. It can be inferred that the rate of
oxygen consumption in the vertical system at 0 cm height was laminar unit was the highest.
Water level is a factor that is not taken into consideration in design and operation of constructed
wetland, which could affect the performance efficiency of contaminant removal such as
ammonia, contaminant that occurs in high concentrations in water domestic waste.
