Tropical peatland stores a large amount of carbon (C) and is an important C sink. In Malaysia, about 25% of the peatland area has been converted to oil palm plantation where drainage, compaction and groundwater table control are prerequisite. To date, relationship between land compaction and C emission from tropical peatland is scarcely studied. To understand the effect of compaction on soil carbon dioxide (CO2) and methane (CH4) flux from tropical peatland, a laboratory soil column incubation was conducted. Peat soil collected from a Mixed Peat Swamp forest were packed in polyvinyl chloride pipes to three different soil bulk densities (BD); 0.14 g cm–3, 0.18 g cm–3 and 0.22 g cm–3. Soil CO2 and CH4 flux from the soil columns were measured on weekly basis for twelve weeks. Total soil porosity and moisture retention of each soil BD were also determined using another set of peat sample packed into 100 cm3 soil core ring. Soil porosity decreased while soil moisture retention increased proportionally with increasing soil BD. Soil CH4 flux were reduced approximately by 22% with compaction. On contrary, soil CO2 fluxes were greater (P ≤ 0.05) at compacted soil when infiltration and percolation of rainwater become slower with time, until soil moisture becomes limiting factor. This study suggested that compaction affects water movement and gaseous transport in the peat profile, thus influences C emission from peat soil.

中文翻译：

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压实对马来西亚沙捞越热带泥炭地土壤 CO2 和 CH4 通量的影响

热带泥炭地储存了大量的碳（C），是重要的碳汇。在马来西亚，大约 25% 的泥炭地面积已转变为油棕种植园，其中排水、压实和地下水位控制是先决条件。迄今为止，几乎没有研究热带泥炭地土地压实与碳排放之间的关系。为了了解压实对热带泥炭地土壤二氧化碳 (CO2) 和甲烷 (CH4) 通量的影响，进行了实验室土壤柱培养。从混合泥炭沼泽森林收集的泥炭土被装入聚氯乙烯管中，制成三种不同的土壤体积密度 (BD)；0.14 g cm-3、0.18 g cm-3 和 0.22 g cm-3。来自土柱的土壤 CO2 和 CH4 通量每周测量一次，持续 12 周。还使用另一组装入 100 cm3 土壤核心环的泥炭样品测定每个土壤 BD 的总土壤孔隙率和水分保持率。随着土壤 BD 的增加，土壤孔隙度降低，而土壤保水量成比例增加。随着压实，土壤 CH4 通量减少了大约 22%。相反，当雨水的渗透和渗透随时间变慢，直到土壤水分成为限制因素时，压实土壤的土壤 CO2 通量更大（P ≤ 0.05）。该研究表明，压实作用会影响泥炭剖面中的水运动和气体传输，从而影响泥炭土壤中的碳排放。随着压实，土壤 CH4 通量减少了大约 22%。相反，当雨水的渗透和渗透随时间变慢，直到土壤水分成为限制因素时，压实土壤的土壤 CO2 通量更大（P ≤ 0.05）。该研究表明，压实影响泥炭剖面中的水运动和气体传输，从而影响泥炭土壤的碳排放。随着压实，土壤 CH4 通量减少了大约 22%。相反，当雨水的渗透和渗透随时间变慢，直到土壤水分成为限制因素时，压实土壤的土壤 CO2 通量更大（P ≤ 0.05）。该研究表明，压实作用会影响泥炭剖面中的水运动和气体传输，从而影响泥炭土壤中的碳排放。