poster - International Conference of Agricultural Engineering

Fig. 2 shows the monitoring results in 2011 and there are not typical differences in the
rice growth and yield components among three sites.
2.2.2. Effect on rice culture and soil characteristics of indirect wastewater reuse
Ponded water depth in the OS and YI sites will be continuously measured by an
automatic float type water level recorder. Two paddy fields will be equipped with an
electronic flow meter with a data logger in the inlet and outlet. Weather data from the Suwon
National Weather Station near the monitoring sites will be collected.
The samples of irrigation and ponded water of each paddy field will be weekly taken to
the laboratory for the growing season and analyzed according to standard methods from
2011 to 2014. The parameters will be analyzed for water quality are pH, EC (electrical
conductivity), DO, TOC, BOD, COD, SS, T-N, T-P, NO 3 -N, NH 4 -N, PO 4 -P, CL - , Cu, SO 4 , Ni,
Ca, Mg, Na, K, Zn, CN, CO 2- 3 , HCO 2- 3 , detergent, total and fecal coliforms and Escherichia
coli.
Soil samples will be taken from each paddy field before and after every crop cycle and
two times during growing season, at depths decreasing from 0 to 0.8 m, every 0.2 m. They
will be analyzed for pH, CEC (cation exchange capacity), EC, TOC, SiO 2 , T-N, T-P, NO 3 -N,
NH 4 -N, P 2 O 5 , Cl - , Cd, Pb, Zn, Cu, Ni, As, Ca, Mg, Na, K, Hg, Mn, Cr 6+ and organic matter
according to the standard method. Fig. 3 shows the analysis results of soil samples for EC
and Na before the crop cycle. Soil samples of the OS and BJ sites irrigated with reclaimed
wastewater contain much more sodium than the YI sites.
FIGURE 3: Soil salinity results of EC and Na at each depth before the crop cycle in 2011
All the collected data are expected to be used as a basic data for assessing crop safety
and environmental impact for agricultural wastewater reuse, and establishing comprehensive
measures for wastewater reclamation and reuse in agriculture.
2.2.3. Guideline of indirect wastewater reuse for agriculture
A guideline of indirect wastewater reuse for agriculture that could minimize adverse
effect on crop safety, agro-ecological environment and human organism will be proposed. In
order to propose the guideline, internal and external water quality standards for agriculture
and wastewater reuse will be extensively reviewed. Furthermore, the effects of wastewater
reuse on the quality of irrigated water will be monitored and simulated through hydrologic and
water quality models. Each monitoring site of indirect wastewater reuse, the OS and BJ, has
10 sampling points, at the pumping station, every 0.5 km down the stream from effluent
outlet to 3.0 km, 4.0 km and 5.0 km. Fig. 4 shows the sampling points for this study.