Physico-Chemical Properties, Carbon Dioxide Emissions and Carbon Stock in Peat Soil used for Turmeric Cultivation at Kuala Langat Selatan, Selangor, MALAYSIA


1Environmental Science Program, Faculty of Science and Natural Resources, Universiti Malaysia Sabah, Jalan UMS, 88400, Kota Kinabalu, Sabah

2Center for Earth Sciences and Environment, Faculty of Science and Technology, UKM 43600 Bangi, Selangor

3Climate Change Institute, UKM, 43600 Bangi, Selangor

*Corresponding author:




Measurement of carbon dioxide emissions in peat soil was done in a turmeric cultivation area on August 2009 and January 2010 at Kampung Tumbuk Darat, Kuala Langat Selatan, Selangor. The objective of this research was to determine the quantity of CO2 emissions from peat soil as well as the carbon stock that is stored in the peat soil. Other parameters that were investigated included soil pH, soil temperature, soil bulk density, soil organic carbon, soil fresh water content, organic matter, humic acid and fulvic acid content. A total of 30 carbon dioxide emission sampling points in rectangular grid arrangement was prepared in a survey plot of 1 hectare. The survey plot was further divided into sub-plots of size 20 m x 25 m. Soil samples were randomly taken at the depth of 0-15 cm to 50-65 cm using an auger. Sampling of CO2 emissions was done using the static alkali absorption method (Kirita Method). The organic carbon content was determined using the Walkley-Black method, while the humic and fulvic acid content was determined using the basic molecule isolation method. Other soil properties were determined using standard methods of determination. The surface temperature of peat soil was between 28oC and 30oC. The bulk density of the area was as low as 0.20 g cm-3. On the other hand, the soil fresh water content, soil organic matter, and peat soil humic acid was very high. The minimum quantity of CO2 emissions in the peat soil on August 2009 and January 2010 was 40.92±21.62 t CO2 ha-1 yr-1 (467.10±246.86 mg CO2 m-2 hr-1) and 41.51±13.41 t CO2 ha-1 yr-1 (473.86±153.12 mg CO2 m-2 hr-1), respectively. Carbon stock for the month of August 2009 and January 2010, respectively was 297.70 t ha-1 and 456.60 t ha-1. T test showed that there were significant (p<0.05) differences in many of the soil parameters such as the pH, water content and organic carbon. Correlation analysis showed that CO2 is influenced by the organic matter, water content and temperature.

Keywords: Humic and fulvic acid, CO2 emissions, carbon stock, peat soil, turmeric

Mechanical Performance of Acetate Lacquer from Acacia mangium

Melissa Sharmah Gilbert Jesuet, Ismawati Palle & Liew Kang Chiang

Wood Technology and Industry Program,
Faculty of Science and Natural Resources (Forestry Complex),
Universiti Malaysia Sabah, Jalan UMS, 88400 Kota Kinabalu, Sabah, Malaysia


Cellulose comprise of about 40–50 % of the composition of wood, making it one of the most abundant organic polymers on earth. Cellulose is very versatile in terms of application, with a wide array of products fabricated, including the chemically modified cellulose derivatives. One of the more prominent and multifaceted derivatives is the cellulose acetate, in which have been used predominantly as cigarette filters, membrane filters, and coating. In this study, the intermediate product, Acacia mangium-produced cellulose acetate was modified into lacquer to produce a feasible wood coating product. The lacquer underwent a series of tests such as impact, abrasion, adhesion, and hardness to evaluate its mechanical performance. The results of the coating were compared to a similarly formulated acetate lacquer that was produced using commercial cellulose acetate instead as a control. Based on the result, it is shown that Acacia mangium-produced cellulose acetate lacquer shows a better impact resistance with a rating of 4 as opposed to the commercial cellulose acetate with a rating of 3 with moderate cracking, with an approximate 6% better abrasion resistance and higher hardness rating class. Meanwhile, the commercial cellulose acetate lacquer presents a better adhesion performance with only 5% flaking compared to the 15% flaking of Acacia mangium-produced cellulose acetate lacquer. The Acacia mangium-produced cellulose acetate lacquer indicates a novel benefit from the presence of impurities from the intermediate Acacia mangium-produced cellulose acetate product such as the plasticizing hemicellulose acetate, as well as the hydrophobic lignin.

Keywords: Cellulose acetate, lacquer, wood coating, mechanical properties