In the present study, lichen(Parmelia sp.) extract showed insecticidal activity against Aedes albopictus, and the effect of growth inhibiting activity was investigated.
Acetone and methanol extracts of the lichen against larvae of Aedes albopictus were showed high insecticidal activities in low lethal concentration.
50% lethal concentration of the acetone extractof the lichen is 0.13% and the 50% lethal concentration of methanol extract of lichen is 0.15% respectively. This experiment that used acetone and methanol extracts of the lichen were observed for 24, 48 and 72 hours. As a result, the higher concentration and the longer exposure time is increased mortality against Aedes albopictus.
Pupation time took more time as the higher concentration of acetone extract of lichen. Consequently, the lichen extract is effect in inhibiting the growth of Aedes albopictus larvae.
In this experiment indicates that lichen extract has activity against Aedes albopictus and is available as the natural insecticide.
This study conducted a laboratory simulation using artificial and natural rainfall in order to investigate the runoff characteristics of livestock resources through the analysis of the surface runoff water and infiltration water by rainfall intensity and fertilization level. Cattle manure and pig liquid fertilizer was used as livestock resource.
As a result of this study, it was observed that the surface runoff occurred over 32 mm/hr rainfall intensity, and flow rate of the surface runoff water and the runoff ratio of contaminant parameters from livestock resource was increased, as rainfall intensity was stronger. With doubled fertilization level, T-N increased in compost and the amount of CODMn runoff also considerably increased in liquefied fertilizer. In the case of natural rainfall, the runoff ratio of T-P clearly increased in compost and the T-N of final surface runoff ratio in compost and liquefied fertilizer was ranged from 0.13047 to 0.13623 with stronger rainfall intensity.
Design approach of Upflow Anaerobic Sludge Blanket(UASB) process based on the biological kinetic parameters are known to be very difficult since the characteristics of the granular sludge depends on the type of wastewater and size distribution of the granular sludge also depends on the upflow velocity in the UASB reactors. Furthermore, industrial wastewater containing toxic substances has been treated by UASB process without the clear knowledge of toxic effects on the granular sludge. Hence, the present research was aimed on the intensive evaluation of biological kinetic parameters of the granular sludge in UASB reactor with and without toxic substance of 2,4-dichlorophenol in order to present the basic design measures for UASB process design. The results could be summarized as follows. The biological kinetic parameters(k and Ks) considerably varied with the granular size of the sludge. Generally, the k and ks values of the granular sludge increased with the particle size of the granule. The biological kinetic parameters(k and Ks) of the granular sludge obtained from batch test were not applicable to design purpose of UASB process due to substrate diffusional limitation into the granular sludge in the completely mixed UASB reactors. The toxic effects on k and Ks greatly varied with the granular size. And as the toxicant concentration increased, the k value decreased while the Ks value increased. Inhibition constant(ki) for k with the toxicant of 2,4-dichlorophenol varied from 0.5 to 2.3 depending on the granular sizes while the inhibition constant(Ki) for Ks varied from 20.7 to 80.1, showing the mixed inhibition.