Roles of Montane Forest inside National Park in Northern Thailand on Carbon and Macronutrient Storages -
Kittsak Lumsonjitt, Soontorn Khamyong, Niwat Anongrak, and Panida Kachina
The potential of carbon and macronutrient storages in a recovery montane forest (MF) inside the Doi Suthep-Pui National Park, Thailand, was assessed after 60 years of establishing the national park. Plant community analysis was carried out for studying the structure, species diversity and biomass production. Fifteen sampling plots, each of size 40 x 40 m2, were arranged using a stratified random technique across an altitudinal range between 1,200 and 1,597 m above mean sea level (m. s. l.). Three 2 m soil pits were used for soil study. Biomass amounts of existing 171 plant species (129 genera and 70 families) were calculated using allometric equations and found that the total biomass of this forest was high as 438.78 megagrams per hectare (Mg/ha). Amounts of carbon (C), nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) stored in the biomass were measured as the following order: 216.81 Mg/ha, 1,959.82, 273.55, 927.82, 3,895.57, and 580.72 kg/ha. Botanical names are referred to Smitinand (2014). Castanopsis acuminatissima had the highest amounts of biomass, carbon, and macronutrients, followed by Schima wallichii, Pinus kesiya, Castanopsis diversifolia, Syzygium sp., Magnolia floribunda, respectively. The species in Fagaceae family contributed to the highest value, 28.47%, followed by Theaceae, Lauraceae, Myrtaceae, respectively. Amounts of C, N, available P, extractable K, Ca, and Mg in Ao layers were estimated at 12.99 Mg/ha, 637.16, 36.37, 146.17, 483.49 and 66.34 kg/ha, respectively while those in the soil were 492.56 Mg/ha, 3,188.37, 71.53, 4,622.26, 5,123.67 and 373.36 kg/ha. Thus, their ecosystem storages were determined as fellow: 722.36 Mg/ha, 5,785.34, 345.46, 5,741.24, 9,502.72 and 1,020.39 kg/ha. The nutrient stocks in the Ao layers and soil were excess for the annual uptake of tree species in the MF.