2010 Volume 1 Issue 2 Pages 33-37
Eucalyptus has been introduced to the farmer and extensively grown in Thailand for paper pulp production and giving high income to the farmer. However, the long term impact of eucalyptus plantation on soil ecosystem has been less studied. Therefore, the aim of this study was to investigate the influence of eucalyptus plantation on the soil ecosystem under different soil series in Northeast Thailand. The study site was located at Amphur Nam Pong, Khon Kaen, Northeast of Thailand. The biological, physical and chemical soil properties in Eucalyptus plantation (more than 3 years) were analyzed compared with the dry dipterocarp forest nearby. Moreover, impacts of eucalyptus on soil biota (Earthworm) under different soil series (Pimai and Nampong soil series) were evaluated in the laboratory. The results indicated that microbial activity such as soil respiration, microbial biomass nitrogen and microbial biomass carbon in Eucalyptus plantation were less than in the dry dipterocarp forest significantly from 3.950 to 5.916 mg C/day for microbial activity and 15.811 and 108.620 µg N/g soil for microbial biomass nitrogen and 102.24 to 244.25 µg C/g for soil microbial biomass carbon (p<0.01), respectively. For the 50% avoidance of the earthworm to eucalyptus leave in Pimai (Pm) and Nampong (Ng) soil series were 17.35 and 19.44 g/kg soil, respectively. The result showed that eucalyptus plantation has adverse effect on soil microbial activity in soil ecosystem and differ in each soil series. The result of this study is useful as decision making in appropriate land use management. The impact of eucalyptus plantation should be considering of site specific location and find out the suitable place to grow eucalyptus.
