Changes in soil organic carbon stocks after conversion from forest to oil palm plantations in Malaysian Borneo
Changes in soil organic carbon stocks after conversion from forest to oil palm plantations in Malaysian Borneo
复制标题
马来西亚婆罗洲从森林转变为油棕种植园后土壤有机碳储量的变化
DOI：
10.1088/1748-9326/aade0f
复制
发表时间：
2018
影响因子：
6.7
通讯作者：
T. B. Bruun
中科院分区：
文献类型：
--
作者：
N. Rahman;A. de Neergaard;J. Magid;Gerrie W. J. van de Ven;K. Giller;T. B. Bruun
全球对棕榈油需求的持续增长导致了工业油棕种植园的大规模扩张——主要是以原始和次生林为代价的。这些转换对环境的潜在负面影响已经引起了更密切的关注。然而，关于森林向工业油棕人工林转化对土壤有机碳储量影响的实证数据缺乏且不完整。在马来西亚婆罗洲沙捞越，我们评估了热带森林转化为油棕种植园后，在第一次和第二次轮作期间碳储量的变化。土壤样本采集自3个年龄层的油棕人工林（分别为49年、39年和29年前），以3个复制样地和4个相邻原生林样地为参考。在每个油棕样地，分别对杂草圈（WC）、叶堆（FS）和棕榈间（BP）三个管理区进行采样。所有土壤样品采集于5个土层（0-5、5-15、15-30、30-50和50-70 cm）。分析样品的有机碳浓度、土壤容重、pH值和土壤质地。结果表明，转换29年、39年和49年后，SOC储量分别下降42%、24%和18%。油棕人工林不同经营区土壤碳储量存在显著差异，各年龄层土壤碳储量变化趋势相似：FS > WC b> BP，表明在评价土壤碳储量时考虑人工林内变异的必要性。参考林与转化人工林有机碳储量差异最大的是表层土壤（0 ~ 15 cm），而底土（0 ~ 30 cm）也存在差异。我们的研究结果将有助于未来的建模和生命周期核算，以计算森林转化为油棕种植园的碳债。
The continuous rise in the global demand for palm oil has resulted in large-scale expansion of industrial oil palm plantations—largely at the expense of primary and secondary forests. The potentially negative environmental impacts of these conversions have given rise to closer scrutiny. However, empirical data on the effects of conversion of forests to industrial oil palm plantations on soil organic carbon (SOC) stocks is scarce and patchy. We evaluated the changes in SOC stocks after conversion of tropical forest into oil palm plantations over the first and second rotation period in Sarawak, Malaysian Borneo. Soil samples were collected from three age classes of oil palm plantations converted from forest (49, 39 and 29 years ago respectively) with three replicate sites and four adjacent primary forest sites as reference. In each site under oil palm, the three management zones, namely weeded circle (WC), frond stacks (FS), and between palm (BP), were sampled separately. All soil samples were collected from five soil layers (0–5, 5–15, 15–30, 30–50 and 50–70 cm). Samples were analysed for SOC concentration, soil bulk density, pH and soil texture. Results showed SOC stocks declined by 42%, 24% and 18% after 29, 39 and 49 years of conversion respectively. Significant differences in SOC stocks were found among different management zones in the oil palm plantations, and the trend was similar for all age classes: FS > WC > BP, demonstrating the necessity of considering within-plantation variability when assessing soil C stocks. The largest differences between SOC stocks of the reference forest and converted plantations were found in the topsoil (0–15 cm depth) but differences were also found in the subsoil (>30 cm). Our results will contribute towards future modelling and life cycle accounting to calculate the carbon debt from the conversion of forest to oil palm plantations.