Evaluation on the decomposability of tropical forest peat soils after conversion to an oil palm plantation
Evaluation on the decomposability of tropical forest peat soils after conversion to an oil palm plantation
复制标题
热带森林泥炭土转为油棕种植园后的可分解性评价
DOI：
10.1016/j.scitotenv.2017.02.165
复制
发表时间：
2017
期刊：
影响因子：
--
通讯作者：
Watanabe A.
中科院分区：
文献类型：
--
作者：
Sangok FE;Maie N;Melling L;Watanabe A.
为了了解热带泥炭土在油棕种植园毁林后分解能力的变化，在马来西亚沙捞越进行了一项田间孵化试验。从混合泥炭沼泽（MPS;Gonystylus-Dactylocladus-Neoscrotechiniaassociation）、Alan Batu （ABt;Shorea albida-Gonstylus-Strenonurusassociation）和Alan Bunga （ABg;Shorea albidaassociation）三种原生林中收集的泥炭土装在聚氯乙烯管中，并安装在油棕种植园中。连续3年每月测量土壤中二氧化碳（CO2）和甲烷（CH4）通量。环境变量包括土壤温度、土壤含水量和地下水位也被监测。3种土壤的pH值、燃失量和总碳(C)含量基本一致，而全氮含量在MPS土壤中高于ABg土壤。基于13c核磁共振（NMR）谱分析，MPS和ABg土壤中C分别以烷基C和反烷基C的形式存在的比例最大。ABt土壤的碳组成介于MPS和ABg土壤之间。3种土壤的co2通量范围为78 ~ 625 mg cm - 2h - 1，与地下水位呈负相关。ch4通量范围为- 67 ~ 653 μ C m−2h−1。co2和ch4总通量在ABg > ABt > MPS量级均较大（P< 0.05）。根据累积碳损失估算的泥炭年分解速率相差2倍，指数衰减模型中MPS土壤的速率常数为0.033 y−1，ABg土壤的速率常数为0.066 y−1。三种森林泥炭土的田间培养结果似乎反映了以多糖为代表的活性有机质含量的差异。
To understand the variations in the decomposability of tropical peat soil following deforestation for an oil palm plantation, a field incubation experiment was conducted in Sarawak, Malaysia. Peat soils collected from three types of primary forest, namely Mixed Peat Swamp (MPS;Gonystylus-Dactylocladus-Neoscrotechiniaassociation), Alan Batu (ABt;Shorea albida-Gonstylus-Strenonurusassociation), and Alan Bunga (ABg;Shorea albidaassociation), were packed in polyvinyl chloride pipes and installed in an oil palm plantation. Carbon dioxide (CO2) and methane (CH4) fluxes from soil were monthly measured for 3 years. Environmental variables including soil temperature, soil moisture content, and groundwater table were also monitored. The pH, loss on ignition, and total carbon (C) content were similar among the three soils, while total N content was larger in the MPS than in the ABg soils. Based on13C nuclear magnetic resonance (NMR) spectroscopy, C composition of the MPS and ABg soils was characterized by the largest proportion of C present as alkyl C andO-alkyl C, respectively. The C composition of the ABt soil was intermediate between the MPS and ABg soils. The CO2fluxes from the three soils ranged from 78 to 625 mg C m− 2h− 1with a negative correlation to groundwater level. The CH4fluxes ranged from − 67 to 653 μg C m− 2h− 1. Both total CO2and CH4fluxes were larger in the order ABg > ABt > MPS (P< 0.05). Annual rate of peat decomposition as was estimated from cumulative C loss differed up to 2 times, and the rate constant in exponential decay model was 0.033 y− 1for the MPS soil and 0.066 y− 1for the ABg soil. The field incubation results of the three forest peat soils seem to reflect the difference in the labile organic matter content, represented by polysaccharides.