不同菌渣肥施用量对柑橘果园土壤有机碳矿化的影响

Effect on the Turnover of Soil Organic Carbon in Citrus Orchard Soils by Adding different Edible Fungus Residues

为阐明不同菌渣肥施用量对柑橘果园有机碳矿化的影响，对定位试验柑橘果园单施化肥、单施有机肥、有机无机肥配施、不施肥处理的土样进行室内培养，定期测定土壤CO2释放量。结果表明，整个培养过程，土壤有机碳矿化速率前期迅速下降，培养中期缓慢下降，培养后期趋于稳定状态。相关分析表明有机碳矿化速率与土壤C／N具有显著相关性。与不施肥和单纯施用化肥相比，施人有机肥的土壤具有更高的微生物活性，从而引起土壤平均有机碳矿化速率提高5．2％～104．6％；但随着有机肥施用量的增加，土壤潜在可矿化C量占总有机碳的比例并没有显著增加，说明通过施用有机肥可以增加果园土壤有机碳的积累。

The CO2 release in Citrus orchard soil samples respectively applied with organic fertilizer, chemical fertilizer, chemical and organic fertilizer were analyzed during their incubation period to study the effects of different edible fungus residues on organic carbon mineralization in orchard soils. The results showed that the rate of SOC mineralization decreased quickly at the beginning, then decreased slowly during the middle incubation time, and kept relatively stable during the later incubation time. Correlation analysis showed that there was a significant correlation between the mineralization rate of SOC and C/N. Compared with the treatments of no-fertilizer and chemical fertilizer, organic fertilizer application in the soil could improve soil microbial activity, and average mineralization rates of the soils increased by 5.2%- 104.6%. But there was no significant increase of potential carbon mineralization in the ratio of total organic carbon with the increasing of the amount of organic fertilizer in citrus orchard with the increase of organic fertilizer, indicated that mixed application of inorganic and organic fertilizer on soil could increase the accumulation of soil organic carbon.