Tài liệu ABOVEGROUND CARBON STOCK ESTIMATES OF RUBBER (Hevea brasiliensis) PLANTATION AT MAKILING FOREST RESERVE doc

* Associate Professor, Institute of Renewable Natural Resources (IRNR), College of Forestry and Natural Resources (CFNR), University of the Philippines Los Banos **Assistant Professor, Department of Forestry and Environmental Science, College of Agriculture and Forestry, Bohol Island State University (BISU), Bilar, Bohol ABOVEGROUND CARBON STOCK ESTIMATES OF RUBBER (Hevea brasiliensis) PLANTATION AT MAKILING FOREST RESERVE ARTURO SA. CASTILLO* and TOMAS D. REYES, JR.** INTRODUCTION Climate change is one of the primary concerns of humanity today (Lasco et al. 2002). The World’s forest is shrinking by 0.38% and converted to other land uses every year. In fact, according to FAO (2003), 23,260 km 2 of forests are destroyed per year in Southeast Asia. Problems leading to poverty rise are even exacerbated by human-aggravated natural disasters. Plantations intended, not for timber but, for other purposes such as fruits and seed sources, and other non-timber products (one of which is latex production) have valuable role in relation to climate change. Similar with the forests, plantations can be sources and sinks of carbon. Its non-use value, carbon sequestration for instance, sometimes outweighs natural forests. Much of the carbon sequestration, according to Lasco and Pulhin (2003), is attributed to the existence of tree plantations with a sequestration rate of up to 15 t ha -1 yr -1 . This study was conducted to determine the immense potential of rubber plantations in sequestering carbon in the MFR aside from the very purpose of establishing this plantation for latex and other uses. Specifically, it provided calculation of the amount of aboveground (tree) carbon based on recent available secondary data, and the assessment of the condition of the site. A nation-wide study is recommended to determine, quantify and value the potential environmental-social contributions and benefits of existing rubber plantations in the Philippines to mitigate climate change. METHODOLOGY Study Site Rubber (Hevea brasiliensis) plantation in Mt. Makiling was established in 1961. Located in Zone 6 of Makiling Forest Reserve (MFR) 14.08 hectares (Almazan et al. 2000), which now totaled to 16 hectares after a series of replanting and expansion Type 1 climate, annual rainfall ranges from 2,481 to 2,681 mm (MBG Monitoring Station 2000), mean annual temperature ranges from 25.5 C to 27.5 C. [...]... vis-àvis carbon stored, it is also imperative to determine C sequestration rates, the period at which C sequestration rates are at maximum; age, and the C pools and fluxes in terms of species and locality Investigate how to maximize the rate of accumulation of atmospheric carbon in rubber plantation in terms of effects of silvicultural treatments/practices like cultivation, weeding, fertilization, thinning,... are composed of trees of much bigger stature Results of the study further showed that rubber plantation exhibited lower tree carbon content compared to a natural forest, a secondary forest, and some fast growing plantations based on previous studies conducted in the country (Lasco and Pulhin 2003) Plantation Assessment Only about 20.16% of rubber trees was found in good quality state Most of them were... above result shows that there is a greater possibility that a plantation forest can attain or even surpass the capacity of a natural forest to store carbon and more than the other forest ecosystems Factors can be attributed to this are good site conditions, proper silvicultural treatments, level of utilization, and human disturbance The same can be attributed to allowing that stand to attain its optimum... Hevea plantation, this estimated aboveground (tree) biomass per hectare computed was a bit below the estimated biomass of Swietenia-dominated plantations (Racelis 2000, Lasco et al 2001), dipterocarps (Racelis 2000), and tree legumes (Lasco et al 2001) in Mt Makiling This could be because the plantations mentioned were established a couple of years earlier than the rubber plantation, and these plantations... Carbon Estimates (in tons) Estimated total aboveground biomass production for the whole plantation was 7,030.51 tons That was about 502.18 tons per hectare Its carbon content per hectare basis, following the conservative estimate of about 45% (Lasco, et al 2003), was calculated to be 225.98 tons, giving a total carbon of about 3,163.73 tons Over thirty-five per cent (35.92%) of the total computed carbon. .. Norhayati, 1992 cited by Chung 2004) The relatively high aboveground (tree) carbon content in the study site (MFR Rubber Plantation) is due to the fact that Hevea, and perhaps Swietenia, are very efficient in converting solar energy into dry matter This holds the same observation with the work of Chung (2004) According to Templeton (1969) cited by Chung (2004), the rate of dry matter production of 5... The density of rubber per hectare was computed 258, while mahogany had 158 individuals Other tree species were counted not more than 50 individuals per hectare each Huge crown of mahogany also restricted solar radiation to reach the forest floor which limits the germination of seeds and the growth of rubber seedlings Table 3 Summary of the plantation assessment in the MFR Rubber Plantation Common... its full maturity (Racelis, 2000) RECOMMENDATIONS Examined some gray areas Include the bio-measurements of other carbon pools which were not considered in this study Specific allometric equations should also be generated following the guidelines Adequate number of permanent plots within the plantation should be established Determine the effectiveness of tree plantations in sequestering carbon, aside... production of 5 ¼ and 6 ¾ years stand of Hevea was 35.5 tons h-1 yr-1, a relatively high value among tree species He also added that at this rate of dry matter production, the efficiency of utilization of solar radiation in a stand of Hevea trees with a closed canopy was calculated to be about 2.8% Naimah, Zainol and Yoon (1992) cited by Chung (2004) also reported that Hevea trees have the highest photosynthetic... the whole plantation was computed to be 6,486.14 m3 This value came from the 231.65 m3 of biomass which was calculated from the 50 plots (100 m2 each) systematically laid in the plantation Tree species which contributed much biomass in the plantation were rubber (Hevea brasiliensis) and mahogany (Swietenia macrophylla) with 166.40 m3 (35.92%) and 129.50 m3 (27.95%), respectively Table 1 List of trees . (BISU), Bilar, Bohol ABOVEGROUND CARBON STOCK ESTIMATES OF RUBBER (Hevea brasiliensis) PLANTATION AT MAKILING FOREST RESERVE ARTURO SA. CASTILLO* and. and benefits of existing rubber plantations in the Philippines to mitigate climate change. METHODOLOGY Study Site Rubber (Hevea brasiliensis) plantation in Mt. Makiling