Variations in Plant Diversity and Carbon Storages among Subtype Communities in a Dry Dipterocarp Community Forest of Mae Tha Sub-district, Mae On District, Chiang Mai Province

Abstract

          Variations of plant diversity and carbon storages among subtype communities in a dry dipterocarp forest were investigated in the Mae Tha sub-district community forest, Mae On district, Chiang Mai province, in 2014. Fifteen sampling plots, each of size 40 x 40 m, were used for vegetation survey and arranged randomly over the forest. The plant data in these plots were collected by measuring stem girths at 1.3 m above ground and tree heights, and then calculated for plant species diversity, biomass and carbon storages. The DDF could be divided into five subtype communities based on dominant tree species: Teng (Shorea obtusa) (DDF-1), Rang (S. siamensis) (DDF-2), Hiang (Dipterocarpus obtusifolius) (DDF-3), Pluang (D. tuberculatus) (DDF-4), and two-needle pine (Pinus merkusii, P-DDF). A total of 83 plant species (69 genera, 42 families) with an average tree density of 2,266 trees ha^-1 was found. These five communities had different quantitative features: species richness, 181, 181, 219, 129 and 213; tree densities,  2,723, 2,115, 2,544, 1,857 and 1,596 trees ha^-1; stem basal areas, 23, 30, 26, 19 and 12 m² ha^-1; species diversity index (SWI), 3.25, 2.97, 3.55, 3.43 and 3.92, and forest condition index (FCI), 3.73, 4.80, 5.87, 6.23 and 3.28, respectively. The biomass amounts of these forest communities were estimated as the following order: 135, 159, 146, 109 and 62 Mg ha^-1, and were calculated to be carbon amounts at 67, 79, 72, 54 and 31 Mg ha^-1, respectively. The average values of plant biomass and stored carbon amounts were calculated at 125±55 and 62±31 Mg ha^-1, respectively. These are basic informations for zoning community forest management by the Mae Tha Sub-district Administrative Organization in order to increasing forest conditions as well as the carbon storage potentials to mitigating the global warming.

Keywords: Carbon Storage, Community Forest, Dry Dipterocarp Forest, Plant Diversity