【摘要】 以宁夏盐池县退化荒漠草原为对象,实施深翻耕+补播（SR）、浅翻耕+补播（QR）和禁牧封育（F）恢复措施,同时以传统放牧为对照（CK）,研究不同恢复措施草地0～10 cm、10～20 cm、20～30 cm和30～40 cm土层土壤总有机碳（SOC）、全氮（TN）及颗粒有机碳（POC）、易氧化有机碳（ROC）、微生物量碳（MBC）、硝态氮（NO₃^--N）、铵态氮（NH₄⁺-N）和微生物量氮（MBN）的变化特征,以探讨不同恢复措施对荒漠草原土壤碳氮及其组分的影响。结果表明:与其他处理相比,QR处理草地的土壤SOC含量(5.50～9.93 g·kg^-1)、土壤TN含量(0.17～0.23 g·kg^-1)、土壤ROC含量(0.53～0.99 g·kg^-1)及土壤MBN含量(62.82～73.20 mg·kg^-1)总体较高;土壤MBC含量(386.00～481.80 mg·kg^-1)及碳、氮各组分占SOC和TN的比例总体以F处理的草地较高;不同恢复措施草地各土层土壤POC、NH₄⁺-N和NO₃^--N含量较CK均有所下降。相关分析表明:SOC含量分别与TN、ROC含量呈极显著正相关（P<0.01）,与MBC含量呈显著负相关（P<0.05）。基于土壤碳、氮固存,在所有的处理中,浅翻耕+补播是退化荒漠草原恢复较为有效的措施。更多还原

【Abstract】 This research investigated the impact of three restorative measures on soil carbon and nitrogen fractions in historically overgrazed desert steppe grassland in Yanchi County,Ningxia.The restorative measures investigated were deep tillage+reseeding（SR）,shallow tillage+reseeding（QR）and grazing exclusion（i.e.enclosure）（F）.Traditional grazing was taken as the control（CK）.Measurements made included soil organic carbon（SOC）,total nitrogen（TN）,particulate organic carbon（POC）,readily oxidizable organic carbon（ROC）,microbial biomass carbon（MBC）,nitrate nitrogen（NO₃^--N）,ammonium nitrogen（NH₄⁺-N） and microbial biomass nitrogen（MBN）for the 0^-10 cm,10-20 cm,20-30 cm and 30-40 cm soil layers.It was found that:1)For the QR treatment,soil SOC content(5.50-9.93 g·kg^-1),soil TN content(0.17-0.23 g·kg^-1),soil ROC content(0.53-0.99 g·kg^<sup>-1) and soil MBN content(62.82-73.20 mg·kg^-1) were generally higher than in other treatments.2)Soil MBC content(386.00-481.80 mg·kg^-1)and the proportions of each component of carbon and nitrogen in SOC and TN were generally higher in the F treatment.3)Soil POC,NH₄⁺-N and NO₃^–-N contents were decreased under the various restorative treatments compared with the CK treatment.4)The contents of POC,NH₄⁺-N and NO₃^--N in each soil horizon were also decreased under the various restorative measures,compared with the CK treatment.Correlation analysis showed that SOC content was significantly positively correlated with TN and ROC content（P<0.01）,and significantly negatively correlated with MBC content（P<0.05）.Based on soil carbon and nitrogen fixation and preservation data,shallow tillage+reseeding was the most effective restorative measure for the degraded desert steppes in this study.更多还原