典型复垦地的SOC和δ13C分布特征及与土壤理化特性的关系

Distribution of SOC and δ13C in Typical Reclaimed Land and Relation with Soil Physicochemical Properties

在济宁市采煤矿区中,选取充填复垦(M1)、非充填复垦(M2)和预复垦(M3)的地块研究土壤有机碳(SOC)和稳定性碳同位素(δ^13C)的空间特征并筛选敏感理化指标,分析 SOC 和δ^13C 与土壤理化特性的关系,比较不同复垦方式的恢复效果。研究表明:(1)3 种复垦方式中,M2 的 SOC 含量已恢复到正常耕地的水平,M1 和 M3的 SOC 含量与各自对照相比仍有一定的差距。M1 的δ^13C 在数值和变化趋势上和 CK1 相比有较大差异,M2 的δ^13C值在表层(0~20 cm)与 CK2 有微小差异,M3 的δ^13C 值在 0~60 cm 土层间均有微小差异。(2)通过与筛选出的敏感理化指标进行相关性分析,发现 SOC 受敏感化学指标的影响较大,δ^13C 值受敏感物理指标的影响较大。(3)非充填复垦方式中 SOC 恢复效果最好,对土壤层次损伤最小,土壤理化指标的副敏感最轻,因而建议济宁矿区优先使用非充填复垦方式进行矿区塌陷地治理。

In Jining coal mining area, the spatial characteristics of soil organic carbon (SOC) and stable carbon isotope (δ^13C) and the sensitive physical and chemical indexes were studied and screened by the three different reclamation modes: filling reclamation (M1), non-filling reclamation (M2) and pre-reclamation (M3). The relation between SOC,δ 13C and soil physical and chemical properties was analyzed in order to compare the recovery effect of different reclamation methods. The result shows that:(1) Among the three reclamation methods, the SOC content of M2 has returned to the level of normal cultivated land, and the SOC content of M1 and M3 is still different from that of each respective control group. The value and variation trend ofδ13C of M1 are significantly different from that of CK1,δ13C of M2 is slightly different from that of CK2 in the surface layer (0-20cm), and there is a slight difference of the δ^13C value of M3 between 0-60 cm soil layers.(2)Correlation analysis with the selected sensitive physical and chemical indicators shows that SOC is greatly affected by sensitive chemical indicators, while delta 13C value is greatly affected by sensitive physical indicators.(3) In the non-filling reclamation method, SOC has the best recovery effect, the least damage to soil layers and the less sensitivity to soil physical and chemical indexesTherefore, The non-filling reclamation method is preferred to be used for subsidence treatment Jining mining area.