Keywords :
plant silica, vegetation changes, tropical seasonal forest
บทคัดย่อ :
Tropical seasonal forest, widely distributed in Thailand and
neighbouring countries, has been exposed to human impact
since the early settlers started to use the forest. Vegetation
changes in the region are important in considering the
influence of global warming and human activities. This study
applied on-site analysis of plant silica in seasonally dry forests
to estimate past vegetation.
Three sites were selected in different forests in Sakaerat,
northeast Thailand: deciduous dipterocarp forest (DDF);
mixed deciduous forest (MDF); and dry evergreen forest
(DEF). On each site, soil samples were collected every 10 cm
down to a depth of one meter. Charcoal pieces in the soil
layers were also collected for radio carbon dating. Many Dipterocarpaceae species characteristic of dry forests,
such as Hopea ferrea, Shorea roxburghii and S. siamensis
produced silica in their leaves. Arundinaria pusilla, a typical
bamboo species in DDF, also produced distinguishable silica.
From one pit in DDF (SD1), carbon dating of charcoal pieces
collected from 40 cm and 20 cm depths were dated as 1157
เอกสารอ้างอิง :
Eguchi, S., Okada, N., Siripatanadilok, S., & Veenin, T. (2009). Opal phytolith fossils in the soil of tropical seasonal forest in Sakaerat, northeast Thailand. Proceedings of the FORTROPII: Tropical Forestry Change in a Changing World, 5, 149-156.
