Characteristics of Total Carbon Release in the Early Stage of Mixed Leaf Litter Decomposition of Three Native Tree Species in Burned Area of Alpine Forest in Northwest Sichuan
[Objective]The aim of this study is to reveal the release characteristics of total carbon during the decomposition process of leaf litter in burned areas,thereby providing a foundation for selecting ap-propriate tree species for the restoration of extensively distributed forest burned areas in northwest Sichuan.[Method]This research focused on the leaf litter of native tree species,specifically Pinus densata(P),Quercus semicarpifolia(Q)and Abies fabri(A).These species were combined into 17 treatments(P、Q、A、PQ3∶1、PQ1∶1、PQ1∶3、PA3∶1、PA1∶1、PA1∶3、QA3∶1、QA1∶1、QA1∶3、PQA2∶2∶1、PQA2∶1∶1、PQA1∶1∶1、PQA1∶1∶2 and PQA1∶2∶2)based on varying species combinations and mass ratios,fol-lowed by field decomposition experiments conduction.[Result]①During the 8-month decomposition process,different treatments of leaf litter in the burned area showed an enrichment of total carbon.Specifi-cally,the total carbon content of leaf litter for treatments P,A,PQ3∶1,QA3∶1,QA1∶1,PA1∶1,PQA2∶2∶1,PQA1∶1∶2 and PQA1∶2∶2 showed an initial increase(0-4 months),followed by a decrease(4-8 months)as decomposition progressed.In contrast,the total carbon content for treatments Q,PQ1∶1,PQ 1∶3,QA1∶3,PA3∶1,PA1∶3,PQA2∶1∶1 and PQA1∶1∶1 showed a continuous increase throughout the entire decomposition period.②After 4 months of decomposition,the total carbon release rate of the major-ity of mixed leaf litter(85.71％,calculated as observed value-expected value)was greater than 0,with PQ 1∶1 and QA3∶1 exhibiting a synergistic effect.Conversely,after 8 months of decomposition,the total carbon release rate of mixed leaf litter(50％,calculated as observed value-expected value)was less than 0,and predominantly observed in the PA and certain PQA combinations(2∶2∶1,2∶1∶1,and 1∶1∶1),with PQA1∶1∶1 showing an antagonistic effect.③PLS regression analysis showed that the initial content of C,N,P,cellulose,total phenols and the ratios of C and N,N and P,C and P,cellulose and N,lig-nin and N,lignin and P were significantly correlated with the mixed effect of carbon release from leaf lit-ter.[Conclusion]The synergistic effect of leaf litter decomposition is enhanced when Q.semicarpifolia(Q)is mixed with either P.densata(P)or A.fabri(A),thereby facilitating greater release of total carbon.
万方数据
维普
