Benjawan Kaewderm, Phimphan Tansakul, and Saowapa Angsupanich

pp. 451 - 465

Abstract

Species diversity of soil algae and environmental relationship were studied from undisturbed and
disturbed forests at Ton Ngachang Wildlife Sanctuary and nearby reserved forests. Soil samples were
collected in both dry and rainy seasons, in May and October 1999 respectively. Soil algal density was estimated by the dilution-culture method, using NSIII medium. The cultures were incubated at 25ºC and room
temperature. Twenty-two genera of soil algae in Cyanophyta, Chlorophyta and Bacillariophyta divisions
were identified: 17 genera from undisturbed forests, 16 genera from disturbed forests and 17 genera from
reserved forests. Cyanophyta showed live highest. Comparison of soil algae from 3 sites and 2 seasons were
analyzed using multivariate analysis of variance (MANOVA). The results indicated no significant difference
between sites and seasons. A detrend correspondence analysis (DCA) ordination of sites and seasons revealed no distinct cluster. Environmental variables were related to the species composition of soil algae by mean of
canonical correspondence analysis (CCA). The significant factors that showed a relationship with the soil
algae were pH, organic matter, available P, total N, exchangeable K, Ca and Mg, moisture content, light
intensity and soil temperature. However, percent variance explained by CCA ordination was very low.