[目的]研究遭受松材线虫Bursaphelenchus xylophilus病危害的马尾松Pinus massoniana林土壤有机碳及其活性组分分布特征，揭示采伐后自然恢复对马尾松次生林土壤碳汇的影响机制，为有机碳库管理提供科学支撑。[方法]2023年3-6月在浙江省杭州市余杭区与临安区，采用空间替代时间调查法，以未遭受危害的马尾松林为对照(ck)，设置4种植被恢复类型:中度采伐恢复5 a(ML5)、中度采伐恢复15 a(ML15)、重度采伐恢复5 a(HL5)和重度采伐恢复15 a(HL15)，比较不同采伐强度采伐后自然恢复下马尾松次生林各土层(0～10、10～20、20～40 cm)土壤有机碳、易氧化碳、颗粒有机碳、微生物生物量碳、水溶性有机碳的变化特征，分析其与土壤理化性质的关系，探究其机制。[结果]①各处理不同土层土壤有机碳及其活性组分质量分数从大到小依次均为土壤有机碳、易氧化碳、颗粒有机碳、微生物生物量碳、水溶性有机碳，且随着土层加深其质量分数相应降低，ML15的0～10 cm 土层中土壤有机碳质量分数最高，为33。53 g·kg-1，ck的20～40 cm 土层中水溶性有机碳质量分数最低，为136。55 mg·kg-1。②相同采伐强度下的马尾松次生林土壤各活性有机碳质量分数均表现为随着其自然恢复年限增加而提高，其中各土层间颗粒有机碳质量分数变化最大，15 a的各土层高于5 a各土层的2。6倍以上;③ML15的0～10cm 土层中各活性有机碳组分质量分数均表现为最高，且均显著高于ck(P＜0。05);④相关性分析表明:土壤中各活性有机碳组分之间及其与硝态氮、铵态氮均呈显著正相关关系(P＜0。05)。[结论]中度采伐对马尾松次生林土壤有机碳及其活性组分具有更显著的促进作用，随自然恢复时间越长越有利于土壤活性有机碳组分质量分数增加，适度采伐马尾松纯林并让其自然恢复可促进土壤碳库积累。图3表3参46
Effects of natural vegetation restoration after logging on soil organic carbon and its active components in Pinus massoniana secondary forests
[Objective]The objective is to study the distribution characteristics of soil organic carbon(SOC)and its active components in Pinus massoniana forest affected by pine wilt disease,so as to reveal the influence mechanism of natural vegetation restoration after logging on soil carbon sink in P.massoniana secondary forest and provide scientific support for organic carbon pool management.[Method]From March to June 2023,in Yuhang District and Lin'an District of Hangzhou City,the undamaged P.massoniana forest was used as the control(ck),four vegetation restoration types were set up by using the space substitution time survey method:moderate logging restoration for 5 a(ML5),moderate logging restoration for 15 a(ML15),heavy logging restoration for 5 a(HL5)and heavy logging restoration for 15 a(HL15)to compare the variation characteristics of SOC,readily oxidizable carbon(ROC),particulate organic carbon(POC),microbial biomass carbon(MBC)and water-soluble organic carbon(WSOC)in different soil layers(0-10,10-20,20-40 cm)of P.massoniana secondary forest under natural recovery after different logging intensities,and their relationship with soil physicochemical properties was analyzed to explore their mechanisms.[Result](1)The content of SOC and its active components in each soil layer ranking from high to low were SOC,ROC,POC,MBC and WSOC,and the content decreased accordingly with the deepening of soil layer.The highest SOC content was 33.53 g·kg-1 in 0-10 cm soil layer of ML15,and the lowest WSOC content was 136.55 mg·kg-1 in 20-40 cm soil layer of ck.(2)Under the same logging intensity,the content of active organic carbon in soil of P.massoniana secondary forest increased with the increase of natural recovery years,among which the content of POC in each soil layer changed the most,and the content of POC in each soil layer of 15 a was over 2.6 times higher than that in each soil layer of 5 a.(3)The content of active organic carbon component in 0-10 cm soil layer of ML15 was the highest,and was significantly higher than that in ck(P＜0.05).(4)The results of correlation analysis showed that there were significant positive correlations among active organic carbon components in soil and between active organic carbon components and NO3--N and NH4+-N(P＜0.05).[Conclusion]Moderate logging has a significant promoting effect on SOC and its active components in P.massoniana secondary forest.The longer the natural recovery time of vegetation,the more favorable it is to increase the content of soil active organic carbon components.Moderate logging of P.massoniana pure forests and their natural recovery can promote soil carbon pool accumulation.[Ch,3 fig.3 tab.46 ref.]
万方数据
维普
