Preservation of organic matter in soils of a climobiosequence in the Main Range of Peninsular Malaysia

查看全文 作　　者：Amir Hossein JAFARZADEH-[1]HAGHIGHI;Jusop [1]SHAMSHUDDIN;Jol [1]HAMDAN;Norhazlin [2]ZAINUDDIN 机构地区：[1]Department of Land Management, Faculty of Agriculture, Universili Putra Malaysia, 43400 Serdang, Selangor, Malaysia;[2]Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia 出　　处：《Journal of Mountain Science》索引2017年第14卷第9期,共13页 基　　金：Universiti Putra Malaysia (UPM);supported by the Research University Grant Scheme (RUGS) under Grant No. 01-02-12-1700RU (9327000) provided by UPM 摘　　要：Limited information is available about factors of soil organic carbon(SOC) preservation in soils along a climo-biosequence. The objective of this study was to evaluate the role of soil texture and mineralogy on preservation of SOC in the topsoil and subsoil along a climo-biosequence in the Main Range of Peninsular Malaysia. Soil samples from the A and B-horizons of four representative soil profiles were subjected to particle-size fractionation and mineralogical analyses including X-ray diffraction and selective dissolution. The proportion of SOC in the 250-2000 μm fraction(SOC associated with coarse sand) decreased while the proportion of SOC in the <53 μm fraction(SOC associated with clay and silt)increased with depth. This reflected the importance of the fine mineral fractions of the soil matrix for SOC storage in the subsoil. Close relationships between the content of SOC in the <53 μm fraction and the content of poorly crystalline Fe oxides [oxalate-extractable Fe(Fe_o) – pyrophosphate-extractable Fe(Fe_p)] and poorly crystalline inorganic forms of Al [oxalateextractable Al(Al_o) – pyrophosphate-extractable Al(Al_p)] in the B-horizon indicated the importance of poorly crystalline Fe oxides and poorly crystalline aluminosilicates for the preservation of SOC in the Bhorizon. The increasing trend of Fe_o-Fe_p and Al_o-Al_p over elevation suggest that the importance of poorly crystalline Fe oxides and poorly crystalline aluminosilicates for the preservation of SOC in the Bhorizon increased with increasing elevation. This study demonstrates that regardless of differences in climate and vegetation along the studied climobiosequence, preservation of SOC in the subsoil depends on clay mineralogy. 关 键 词：马来西亚半岛 土壤有机质 保存 土壤有机碳储量 X-射线衍射 铝硅酸盐 铁氧化物 SOC