MORATORIUM FIRE AND LOGGING INCREASE ABOVE GROUND CARBON STOCK: A CASE STUDY IN BURNT PEAT AREA OF EX-MEGA RICE PROJECT, CENTRAL KALIMANTAN, INDONESIA

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1 MORATORIUM FIRE AND LOGGING INCREASE ABOVE GROUND CARBON STOCK: A CASE STUDY IN BURNT PEAT AREA OF EX-MEGA RICE PROJECT, CENTRAL KALIMANTAN, INDONESIA Bambang Hero Saharjo Forest Fire Laboratory, Division of Forest Protection, Department of Silviculture, Faculty of Forestry, Bogor Agricultural University (IPB), Kampus IPB Darmaga, Bogor 16680, West Java, Indonesia. Telp.(62251) , Fax.(62251)( ), bhsaharjo@gmail.com Abstract Forest fire drastically changed the structure and composition of vegetation following burning. Research done in the secondary peat swamp forest located at ex-mega rice project in Central Kalimantan shown that repeated secondary peat swamp forest burned reduced the number of tree species and shrub which left only 12 species compared to 15-years undisturbed secondary peat swamp forest burned which have 17 species of trees, 24 species of pole, 33 species of sapling, 31 species of seedling and 16 species of understorey. Repeated burned site above ground carbon stock only 6.49 ton/ha, while 15-years undisturbed secondary peat swamp forest burned carbon stock ton/ha. This facts shown that moratorium fire and logging will give better environment to vegetation to grow up which increased above ground carbon stock due to the increasing of above ground biomass. Keywords: Moratorium, Forest Fire, Logging, Carbon stock, Biomass, Peat INTRODUCTION Biomass burning is the burning of the world s living and dead vegetation, including grasslands, forests and agricultural lands following the harvest for land clearing and land-use change. Biomass burning is considered a major source of trace gas species and aerosol particles (Logan et al., 1981) which play a vital role in tropospheric chemistry and climate (Crutzen and Andreae, 1996). When an ecosystem such as a tropical rain forest is burnt it can no longer act as a sink for atmospheric CO 2. The CO 2 released is not reincorporated, since the rain forest is not replaced. This affects the global carbon cycle in two ways (Kambis and Levine, 1996): 1. The carbon once stored in forest structure material must now be redistributed within the reservoirs of the global carbon cycle, 2. An area once acting as a sink for atmospheric CO 2 no longer does so. Overall, forest ecosystems store 20 to 100 times more carbon per unit area than croplands and play a critical role in reduction ambient CO 2 levels by sequestering atmospheric carbon in the growth of woody biomass through the processes of

2 photosynthesis (Andrasko, 1990). Fire can therefore be considered one of the local points of the multiple relationships between humans and the environmental changes in fire patterns can be taken as indicator of change in land-use patterns and overall environmental conditions (Malingreau and Gregorie, 1996). RESEARCH METODOLOGY A. Research Site The research conducted at ex-mega rice project located in Taruna and Hampagan site in Central Kalimantan Province at repeated secondary peat swamp forest burned (Figure 1) and 15-years undisturbed secondary peat swamp forest burned (Figure 2). B. Instruments and Laboratory analysis Instruments used to conduct the research divided into laboratory and field instruments. Laboratory instruments such as oven. Field instruments such as knifes, GPS, digital camera, lap top, scale, etc. C. Methode 1. Plot establishment Four (4) plot of 0.1 ha at each burned site was established then in each plot of 2 m x 2 m sub-plot submitted for understorey measurement through destructive sampling. 2. Vegetation Analysis In order to know the vegetation structure and composition changing then 400 m 2 (20 m x 20 m), 100 m 2 (10 m x 10 m), 25 m 2 (5 m x 5 m) and 4 m 2 (2 m x 2 m) sub-plot was established in the plot of 400 m 2 each. In these sub-plots, all seedling, sapling, pole and trees and also under growth vegetation was calculated its species and number. Criteria used for seedling, sapling, pole and trees (Soerianegara and Indrawan 1998) was as follows: Seedling means vegetation that has 1.5-m height, Sapling means vegetation that has 1.5-m height until seedling with 10-cm diameter, Pole means vegetation that has cm diameter, Trees means vegetation that has > 20-cm diameter. At 15-years secondary undisturbed peat swamp forest burned, all seedling, sapling, pole and trees found in the plot was recorded its species and diameter and calculated also its number and diameter.

3 Important Value Index (IVI) Vegetation analysis is the way to study species composition and vegetation structure in one ecosystem (Soerianegara and Indrawan, 1998). In the vegetation analysis it was calculating Important Value Index. According to Odum (1971), IVI was numbering density relative (DR), frequency relative (FR) and dominance relative (DR). 2. Above ground biomass a. Field measurement In oder to measure the biomass through destructive sampling at both side, for trees, pole, sapling, was cut by using group diameter, while seedling and understoreys (shrubs, grass and litter) were directly cut and cleaned, separated according to morphological compartments, weighed and recorded. For each samples a 200 gr. of fresh sample was taken for analysis in the laboratory, to determine the basic characters, similar to the method used for tree morphological compartments. b. Moisture Content About 2 gram of test sample was weighed (B0 x ), and oven dried with temperature of 105 ± 3 C for 24 hours to determine the dry weight (DW x ). Water contents of each test sample (WC x ) were calculated. c. Biomass Biomass of vegetation found in the plot were calculated by using the following equation: Bx = (TDW x 100)/A, Where, Bx is the biomass of each type of vegetation (kg), TDW is the total dry weight of each vegetation (kg) and A is the plot area (m 2 ). 3. Carbon stock Carbon of the biomass found in the site was calculated at dry weight base multiple by 0.5. RESULT AND DISCUSSION Vegetation Structure and Composition Based on the vegetation analysis done in the primary peat swamp forest, it had been found 32 species of trees with density 25,840 /ha, 18 species of pole with density 6,840/ha,

4 43 species of sapling with density 1,510/ha, 23 species of seedling with density 380/ha and 6 species of understorey with density 120/ha. At the 15-years undisturbed secondary peat swamp forest burned, 17 species of trees with density 8,330/ha, 24 species of pole with density 18,960/ha, 33 species of sapling with density 10,000/ha, 31 species of seedling with density 1,010/ha and 16 species of understorey with density 1,260/ha. Repeated burning site just left 12 species of trees and understorey which dominated by Kelakai (Stenochlaena palustris) for % and Lampasau (Nephrolepis radicans) for %. Repeated burning occurred at the same place trend to clean the vegetation which leads to have the land with lower number and quality of species left (Saharjo and Nurhayati, 2006). The effect of fire depends on the fire regime and a change in the fire regime can change the prospect of the communities (Bond and Wilgen, 1996). Damaging in peat swamp forest has decreased diversity of tree species and their regeneration (Istomo et al., 2009), while the severity of fire damage in the burned stands was related to the intensity of logging: the higher the previous logging intensity the heavier the damage by the fire (Matius et al., 2000). Above Ground Carbon Stock Above ground biomass found at the 15-years undisturbed secondary peat swamp forest burned totally was ton/ha, that dominated by stem ton/ha (77.9%) followed by branches 27.2 ton/ha (5.9%), twigs 23.0 ton/ha (4.9%), leaves 22.1 ton/ha (4.7%), necromass 14.2 ton/ha (3.0 %), fresh litter 11.2 ton/ha (2.4%), and old litter 5.4 ton/ha (1.2 %). Meanwhile above ground carbon stock at the 15-years undisturbed secondary peat swamp forest burned totally was ton/ha, that dominated by stem ton/ha (80.5%), followed by branches 15.9 ton/ha (6.0%), twigs 13.5 ton/ha (5.1%), leaves 8.0 ton/ha (3.0%), necromass 8.3 ton/ha (3.1 %), fresh litter 4.0 ton/ha (1.5%), and old litter 1.9 ton/ha (0.8%). Above ground biomass found at repeated secondary peat swamp forest burned was 12.9 ton/ha or equal to 6.49 ton/ha of carbon stock. One of the important information needed following this biomass burning is how long the burnt forest or land can be recovered, and how worst the changing occurred. The tropical forests are often describes as the "green lungs" of the earth by the popular trees. The underlying implications of this characterization is that these forest absorbs more carbon dioxide (CO 2 ) during the daytime in the processes of photosynthesis than they emit at night through respiration. This is true for healthy, growing trees but not necessarily for a forest a

5 whole. Forests with net growth are capable of net absorption of CO 2, whereas mature forests with little growth hold carbon stocks but are unable to absorb additional CO 2. Forests that experience a net loss of biomass volume through mortality due to over maturity, disease or fire become net emitters of CO 2 (Kyrklund, 1990). CONCLUSION Research done in the seconday peat swamp forest shown that repeated burning decrease the number of tree species and understorey which left only 12 species, and also reduce the above ground carbon stock to be only 6.49 ton/ha, while the 15-years undisturbed secondary peat swamp forest burned have 17 species of trees, 24 species of pole, 33 species of sapling, 31 species of seedling and 16 species of understorey, and produce above ground carbon stock ton/ha. This fact shown that moratorium of fire and logging increased the number of tree species, pole, sapling, seedling, understorey and above ground carbon stock. Acknowledgment Author thanks to JST/JICA and Ministry of National Education who support the research through funding assiastance. REFERENCES Andrasko, A Global warming and forests: an overview of current knowledge. Unasylva 163(41): 1-9 Bond, W.J and B.W. van Wilgen Fire and Plants. New York: Chapman and Hall. Crutzen, P.J and M.O. Andreae Biomass burning in the tropics: Impact on atmospheric chemistry and biogeochemical cycles. Science 250: Istomo, Wibowo C, and Wibisono ITC Plant diversity and biomass content in relation with wise use of tropical peatland. Kambis, A.D and J.S.Levine Biomass production of carbon dioxide: A numerical study. In: Levine, J.S (eds.). Biomass burning and global change. Vol.1. The MIT press. P: Kyrklund B (1990) The potential of forests and forest industry in reducing excesses atmospheric carbon dioxide. Unasylva 41: Malingreau, J.P and J.M. Gregorie Developing a global vegetation fire monitoring system for global change studies; A frame work. In: Levine, J.S (eds.). Biomass burning and global change. Vol.1. The MIT press.pp: 14-24

6 Matius P, Toma T and Sutisna M (2000) Tree species composition of a burned lowland dipterocarp forest in Bukit Soeharto, East Kalimantan. Ecological Studies, Vol.40: Spriger-Verlag Tokyo Mori, T Effects of droughts and forest fires on dipterocarp forest in East Kalimantan. Ecological Studies, Vol.40: Spriger-Verlag Tokyo. Odum EP (1971) Fundamentals of Ecology. W.B. Sanders Co. Philadelphia. 574 pp. Saharjo, B,H and Nurhayati, A,D Domination and composition structure change at hemic peat natural regeneration following burning: A case study in Pelalawan, Riau Province. Biodiversitas 7 (2): Soerianegara I and Indrawan A (1998) Ekologi Hutan Indonesia. Laboratorium Ekologi, Fakultas Kehutanan IPB. Bogor.

7 Figure 1. Vegetation found at repeated secondary peat swamp forest burned Figure 1. Vegetation found at 15-years undisturbed secondary peat swamp forest burned