Geoenvironment, Institute of Geography, Earth Science Department, Graduate School of Science, Tohoku University, Sendai, Japan.
PLoS One. 2013 Jul 30;8(7):e70323. doi: 10.1371/journal.pone.0070323. Print 2013.
Increasing prices and demand for biofuel and cooking oil from importer countries have caused a remarkable expansion of oil palm plantations in Indonesia. In this paper, we attempt to monitor the expansion of oil palm plantations on peat land and in tropical forests. We measure the GHG emissions from the land conversion activities at provincial scale. Using Landsat images from three different periods (1990s, 2000s and 2012), we classified LULC of the Riau Province, which is the largest oil palm producing region in Indonesia. A hybrid method of integration, generated by combining automatic processing and manual analysis, yields the best results. We found that the tropical rainforest cover decreased from ∼63% in the 1990s to ∼37% in the 2000s. By 2012, the remaining tropical rainforest cover was only ∼22%. From the 1990s to the 2000s, conversion of forests and peat lands was the primary source of emissions, total CO2 emitted to the atmosphere was estimated at ∼26.6 million tCO2.y(-1), with 40.62% and 59.38% of the emissions from conversion of peat lands and forests, respectively. Between 2000 and 2012, the total CO2 emitted to the atmosphere was estimated at ∼5.2 million tCO2. y(-1), with 69.94% and 27.62% of the emissions from converted peat lands and converted forests, respectively. The results show that in the Riau Province, the oil palm industry boomed in the period from 1990 to 2000, with transformation of tropical forest and peat land as the primary source of emissions. The decrease of CO2 emissions in the period from 2000 to 2012 is possibly due to the enforcement of a moratorium on deforestation.
随着进口国生物燃料和食用油需求的增加，印度尼西亚的油棕种植园显著扩张。本文旨在监测油棕种植园在泥炭地和热带森林中的扩张情况。我们在省级尺度上衡量了土地转换活动产生的温室气体排放。利用三个不同时期（1990 年代、2000 年代和 2012 年）的 Landsat 图像，对印度尼西亚最大的油棕生产区廖内省的土地利用/土地覆盖变化进行分类。通过自动处理和手动分析相结合的混合方法，得到了最佳结果。结果表明，热带雨林的覆盖面积从 1990 年代的约 63%减少到 2000 年代的约 37%。到 2012 年，剩余的热带雨林覆盖面积仅为约 22%。1990 年代至 2000 年代期间，森林和泥炭地的转换是排放的主要来源，估计向大气排放的总二氧化碳量约为 2660 万吨 CO2.y(-1)，其中来自泥炭地和森林转换的排放量分别为 40.62%和 59.38%。2000 年至 2012 年期间，向大气排放的总二氧化碳量估计约为 520 万吨 CO2.y(-1)，其中来自转换泥炭地和转换森林的排放量分别为 69.94%和 27.62%。结果表明，在廖内省，1990 年至 2000 年期间油棕产业蓬勃发展，热带森林和泥炭地的转化是排放的主要来源。2000 年至 2012 年期间二氧化碳排放量的减少可能是由于停止砍伐森林的禁令生效。
