【摘要】 对甘肃省定西市黄土丘陵区不同植被恢复方式下的土壤水分、pH、有机碳(SOC)、全氮(TN)、碱解氮(AN)、全磷(TP)、速效磷(AP)、速效钾(AK)及微生物生物量、呼吸速率、呼吸熵(qCO2)以及微生物熵(qMB)进行了测定与分析。结果表明:不同植被恢复方式下,土壤pH值变化差异不显著(p>0.05);0~20cm土壤的SOC、TN、AN、TP、AP、微生物量碳(SMBC)、微生物量氮(SMBN)含量及微生物呼吸速率(MR)均为天然植被(CL)下最高,AK为自然恢复(Q)方式下最高,qCO2与qMB在人工重建+自然恢复(RZ)方式下最高;20~40cm土壤的SOC、TN、AN、TP、AP含量变化同0~20cm,AK、SMBC、SMBN、qMB及MR在RZ方式下最高;40~60cm土壤的SOC、TN、AN、AP及TP含量在CL方式下最高,SMBC、SMBN、qMB及MR在RZ方式下最高,AK、qCO2在Q方式下最高。相同植被恢复方式下,随土层深度增加,SOC、TN、AN、TP、AP、AK、SMBC、SMBN含量及qMB、MR均逐渐降低,但qCO2逐渐升高(除RZ方式)。不同植被恢复方式,SOC、TN、AN、SMBC、SMBN、qMB、MR及qCO2之间存在不同程度的相关性。更多还原

【Abstract】 Soil physical-chemistry(soil water content,pH,organic total carbon,total nitrogen,available nitrogen,total phosphorus,available phosphorus and available potassium)and microbial characteristics(soil microbial biomass,microbial respiration,metabolic quotient,microbial quotient)of different vegetation restoration modes were determined and analyzed in Dingxi loess hilly region.The results showed there was no significant difference of soil pH between different vegetation restoration modes.In0-20 cm soil layer,pure plantation(CL)restoration mode had the highest content of soil organic total carbon(SOC),total nitrogen(TN),available nitrogen(AN),total phosphorus(TP),available phosphorus(AP),soil microbial biomass carbon(SMBC),soil microbial biomass nitrogen(SMBN)and microbial respiration(MR),natural(Q)restoration mode had the highest available potassium(AK),while artificial+natural(RZ)had the highest metabolic quotient(qCO2)and microbial quotient(qMB);In20-40 cm soil layer,the highest content of SOC,TN,AN,TPand AP were consistent with 0-20 cm soil layer,AK,SMBC,SMBN,qMBand MRof RZ restoration mode was the highest among the restoration modes while the highest of qCO2was in the restoration modes of Q.In 40-60 cm,the highest content of SOC,TN,AN,APand TPappeared at CL restoration mode while SMBC,SMBNand qMB,MR were at the RZ restoration mode,and AK and qCO2was the restoration modes of Q restoration mode.With the increase of soil depth,the content of SOC,TN,AN,TP,AP,AK,SMBC,SMBN,qMBand MRreduced gradually,but qCO2rose gradually under the same vegetation restoration mode,which except for RZ restoration mode.Meanwhile,the result of correlation analysis indicated that there were significant correlations among SOC,TN,AN,SMBC,SMBN,qMB,MR and qCO2.更多还原