Sains Malaysiana 49(3)(2020): 471-481

http://dx.doi.org/10.17576/jsm-2020-4903-02

Characterization and Impact of Peat Fires on Stabilization of Tropical Lowland Peats in Banting, Selangor, Malaysia

(Pencirian dan Impak Kebakaran Gambut kepada Penstabilan Gambut Tropika di Banting, Selangor, Malaysia)

AZLAN SHAH NERWAN SHAH¹*, KHAIRUL AZLAN MUSTAPHA¹ & ROSLAN HASHIM²

¹Department of Geology, Faculty of Science, University of Malaya, 50600 Kuala Lumpur, Federal Territory, Malaysia

²Department of Civil Engineering, Faculty of Engineering, University of Malaya, 50600 Kuala Lumpur, Federal Territory, Malaysia

Diserahkan: 17 April 2019/Diterima: 23 November 2019

ABSTRACT

Peat soil is a representative material of soil and well known as rich in organic matters, high compressibility, high porosity and low shear strength. During dry seasons, peat lands will lose lots of water and potentially turn into a tinderbox bringing in fires. When peat forest fires happen, it prompts degradation of humic-rich organic matter eventually reduce the stability of peat soil. The impacts of peat fire on peat soil from degraded area in Banting, Selangor, Peninsular Malaysia, were investigated through the field identification, physical and engineering properties through burnt peat site. The Unconfined Compressive Strength (UCS) result shows the burnt peat soil gained in strength that strongly related to the binder and filler dosage, moisture content of peat and curing time. The value of UCS strength increased with the gain of moisture content of peat samples but the strength tends to decrease when the moisture content exceeds certain point. The organic material changed its physical and chemical structure resulting from the fire event, thus, the capability of the soil to hold water particles is reducing and yielded higher UCS strength of cement-peat-stabilization. The most important geotechnical aspects of peat that have effect on stabilization process are natural water content, humification grade, ash content, and pH value. The results also suggested that lateral variation within the peat basin indirectly affects the strength of cement-peat-stabilization. The strength of burnt peat can be considerably improved by stabilization and support the concept of Air Curing Technique.

Keywords: Air Curing Technique; cement-peat-stabilization; lateral variation; peat fires, Unconfined Compressive Strength

ABSTRAK

Tanah gambut adalah bahan wakil untuk tanah dan dikenali sebagai tanah yang mempunyai kandungan organik yang tinggi, kebolehmampatan tinggi, keporosan yang tinggi dan kekuatan ricih yang rendah. Ketika musim kemarau atau kering berlaku, tanah gambut akan kehilangan banyak kandungan air dan boleh menjadi ‘bom masa’ yang membawa kepada kebakaran. Ketika kebakaran hutan gambut berlaku, ia segera mendegradasi humik kaya bahan organik yang akhirnya mengurangkan kestabilan tanah. Kesan kebakaran gambut di tanah gambut dari kawasan terdegradasi di Banting, Selangor, Semenanjung Malaysia telah dikaji melalui pencirian lapangan, sifat fiziko-kimia dan kejuruteraan melalui kawasan tapak gambut terbakar. Hasil ujian Mampatan Tidak Terkurung (UCS) menunjukkan kekuatan sampel tanah gambut adalah saling berkaitan dengan pengikat dan dos pengisi, kandungan kelembapan gambut dan masa pengawetan. Nilai kekuatan UCS meningkat dengan peningkatan kandungan kelembapan sampel gambut tetapi kekuatannya mulai menurun apabila kandungan kelembapan melebihi titik tertentu. Struktur fizikal dan kimia bahan organik telah berubah akibat daripada kejadian kebakaran, justeru, keupayaan tanah untuk memegang zarah air berkurang dan menghasilkan kekuatan UCS yang lebih tinggi dalam penstabilan simen-gambut. Aspek geoteknikal yang paling penting dalam memberi kesan kepada proses penstabilan adalah kandungan air semula jadi, gred humifikasi, kandungan abu dan nilai pH. Hasil keputusan juga mencadangkan bahawa variasi mendatar dalam lembangan gambut secara tidak langsung mempengaruhi kekuatan penstabilan-simen-gambut. Kekuatan sampel tanah gambut terbakar dapat dikuatkan dengan kaedah penstabilan dan menyokong konsep Teknik Pengawetan Kering.

Kata kunci: Kebakaran gambut; mampatan tidak terkurung; penstabilan-simen-gambut; variasi mendatar; Teknik Pengawetan Kering

RUJUKAN

Alwi, A. 2008. Ground improvement of Malaysian peat soils using stabilized peat-column techniques. PhD Thesis. University of Malaya (Unpublished).

Anderson, J.A.R. 1964. The structure and development of the peat swamps of Sarawak and Brunei. J. Trop. Geogr. 18: 7-16.

Andriesse, J.P. 1988. Nature and Management of Tropical Peat Soils. 1st ed. Rome: FAO.

ASTM. 2007. Standard Test Methods for Moisture, Ash, and Organic Matter of Peat and Other Organic Soils. American Society for Testing and Material. ASTM Standard D2974 - 07a.

Axellson, K., Johansson, S.E. & Andersson, R. 2002. Stabilization of Organic Soils by Cement and Puzzolanic Reactions. Feasibility Study, Linkoping (Sweden). 3rd report of Swedish Deep Stabilization Research Centre.

Bragazza, L., Buttler, A., Siegenthaler, A. & Mitchell, E.A.D. 2008. Plant litter decomposition and nutrient release in peatlands. In Carbon Cycling in Northern Peatlands, edited by Baird, A., Belyea, L., Comas, X., Reeve, A.S. & Slater, L.D. Geophysical Monograph Series 184: 99-110.

BS 1377: Part 2. 1990. Methods of Test for Soils for Civil Engineering Purposes, Classification Tests. British Standard Institute.

BS 1377: Part 7. 1990. Methods of Test for Soils for Civil Engineering Purposes. Shear Strength Tests Total Stress. British Standard Institute.

Duraisamy, Y., Huat, B.B.K. & Aziz, A.A. 2007. Compressibility behaviour of tropical peat reinforced with cement columns. Am. J. Appl. Sci. 4(10): 786-791.

Huat, B.B.K. 2004. Organic and Peat Soil Engineering. Serdang: Universiti Putra Malaysia Press.

Huat, B.B.K., Kazemian, S., Prasad, A. & Barghchi, M. 2011. State of an art review of peat: General perspective. International Journal of the Physical Sciences 6(8): 1988-1996.

Janz, M. & Johansson, S.E. 2002. The Function of Different Binding Agents in Deep Stabilization. Linkoping (Sweden): 9th Report of Swedish Deep Stabilization Research Centre.

Jinming, H. & Xuehui, M. 2009. Physical and chemical properties of peat. In Coal, Oil, Shale, Natural Bitumen, Heavy Oil and Peat (Vol II), Encyclopedia of Life Support Systems. EOLSS Publications. pp. 309-327.

Kalantari, B. & Huat, B.B.K. 2008. Peat soil stabilization, using ordinary Portland cement, porypropylene fibers, and air curing technique. Electronic Journal of Geotechnical Engineering 13: 1-13.

Kazemian, S., Huat, B.B.K., Thamer, A., Ahmad, A. & Farah, N.A.A. 2010. The acidic and alkaline peat nature effect on cementation and pozzolanic reactions in cement column. 3rd International Conference on Problematic Soils, April 7-9, Adelaide, Australia. pp. 191-196.

Kon, T.W., Bong, C.F.J., King, J.H.P. & Leong, C.T.S. 2012. Biodiversity oftermite (Insecta: Isoptera) in tropical peat land cultivated with oil palms. Pak. J. Biol. Sci. 15: 108-120.

Melling, L. 2016. Peatland in Malaysia. In Tropical Peatland Ecosystem, edited by Mitsuru, O. & Nobuyuki, T. Sapporo, Japan: Springer. pp. 59-70.

Mineral and Geoscience Department. 2007. Guideline for Engineering Geological Investigation in Peat and Soft Soils by the Engineering Geology Working Group. Mineral and Geoscience Department of Malaysia.

Moore, T.R., Trofymow, J.A. & Prescott, S.M. 2005. Patterns of decomposition and carbon, nitrogen and phosphorus dynamics of litter in upland forest and peatland sites in Central Canada. Can. J. For. Res. 35(1): 133-142.

Moayedi, H. & Mosallanezhad, M. 2017. Physico-chemical and shrinkage properties of highly organic soil treated with non-traditional additives. Geotech. Geol. Eng. 35: 1-11.

Murtedza, M., Padmanabhan, E., Mei, B.L.H. & Siong, W.B. 2002. The peat soils of Sarawak. University Malaysia Sarawak, Sarawak, Malaysia. Individual partner report. In STRAPEAT (Strategies for Implementing Sustainable Management of Peatlands in Borneo) Status Report (March 2002). p. 16.

Murayama, S. & Zahari, A.B. 1996. Decomposition of tropical peat soils. JARQ 30: 45-151.

Nuruddin, A., Leng, H.M. & Basaruddin, F. 2006. Peat moisture and water level relationship in tropical peat swamp forest. J. Appl. Sci. 6: 2517-2519.

Page, S.E., Rieley, J.O., Shotyk, O.W. & Weiss, D. 1999. Interdependence of peat and vegetation in a tropical peat swamp forest. Phil. Trans. R. Soc. Lond. B. 354: 1885-1897.

Paramananthan, S. 2011. Keys to Identification of Malaysian Soils using Parent Materials (Mimeo). 2nd ed. Param Agricultural Soil Survey (M) Sdn. Bhd.

Paramananthan, S., Zauyah, S., Lim, C.P., Chan, Y.K. & Boaklan, D. 1984. Proposals for a unified classification of organic soils in Malaysia. Proc. Workshop on Classification and Management of Peat in Malaysia, MSSS.

Rein, G., Cleaver, N., Ashton, C., Pironi, P. & Torero, J.L. 2008. The severity of smouldering peat fires and damage to the forest soil. Catena 74: 304-309.

Tie, Y.L. & Kueh, H.S. 1979. A review of lowland organic soils of Sarawak. Technical paper No. 4 Sarawak, Malaysia, Research Branch, Department of Agriculture.

Usup, A., Hashimoto, Y., Takahashi, H. & Hayasaka, H. 2004. Combustion and thermal characteristics of peat fire in tropical peatland in Central Kalimantan, Indonesia. Tropics 14: 1-19.

Von Post, L. 1922. Sveriges geologiska undersoknings torvinventering och nagre av dess hittills vunna resultat. Sr. Mosskulturfor. Tidskr 1: 1-27.

Wong, L.S. 2010. Stabilization of peat by chemical binders and siliceous sand. PhD Thesis, University of Malaya (Unpublished).

Wood, S.W. & Balfour, V.N. 2010. The effects of soil texture and ash thickness on the post-fire hydrological response from ash-covered soils. Journal of Hydrology 392(3-4): 14-23.

Xintu, L. 2009. Condition of peat formation. Encyclopedia of Life Support Systems. pp. 298-308.

Yule, C.M. 2010. Loss of biodiversity and ecosystem functioning in Indo-Malayan peat swamp forests. Biodivers. Conserv. 19: 393-409.

Zulkifley, M.T.M. 2014. Peat stabilization, organic geochemistry and related palynological characteristics of a tropical lowland peat basin in the Kota Samarahan-Asajaya Area, West Sarawak, Malaysia. Ph.D. Thesis. University of Malaya (Unpublished).

Zulkifley, M.T.M., Fatt, N.T., Raj, J.K., Hashim, R. & Ashraf, M.A. 2014. The effects of lateral variation in vegetation and basin dome shape on tropical lowland peat stabilization in the Kota Samarahan-Asajaya area, West Sarawak, Malaysia. Acta Geologica Sinica 88(3): 894-914.

*Corresponding author; email: azlansnerwans92@gmail.com