短期放牧对昭苏草甸草原土壤活性有机碳组分的影响

采用小区控制放牧试验,在昭苏草甸草原上研究了短期放牧对土壤有机碳含量、土壤易氧化碳含量及其分配比例、土壤颗粒组分比例、土壤轻组组分比例的影响。结果表明,与对照相比,短期放牧地可以降低0-10 cm土层土壤有机碳含量,但差异不显著(P0.05),增加0-10 cm的土壤易氧化碳分配比例、颗粒组分比例。放牧强度对土壤易氧化碳分配比例、颗粒组分比例的影响波动性较大,而对土壤有机碳、易氧化碳与轻组组分比例的影响不显著(P0.05);初步认为10-20 cm土层易氧化碳、易氧化碳分配比例与颗粒组分比例,尤其是易氧化碳分配比例,可作为昭苏草甸草原土壤有机碳动态的敏感性指标。

Effects of short-period grazing on soil active organic carbon fractions in Zhaosu meadow steppe

The influence of grazing on soil organic carbon content, soil readily oxidizable carbon and its distribution ratio, soil particulate component ratio, soil light fraction component ratio in Zhaosu meadow steppe were studied in grazing experiment plot with short period. The result showed that there was no significant effects of short-period grazing on soil organic carbon content although which decreased compared with CK at 0-10 cm soil layer (P0.05). The readily oxidizable carbon distribution ratio and particulate component ratio of 0-10 cm soil layer increased after grazing. There was no significant effects of different grazing intensity on soil organic carbon, readily oxidizable carbon and light fraction component ratio (P0.05). However, there were great fluctuations on the readily oxidizable carbon distribution ratio and particulate component ratio. Soil readily oxidizable carbon, readily oxidizable carbon distribution ratio, soil particulate component ratio of 10-20 cm soil layer, especially readily oxidizable carbon distribution ratio, could be used as sensitive indicators of soil organic carbon dynamics in the study region.