Research On Potential Effects Of Repeated Eucalyptusplanting On Soil Organic Carbon Storage And Spectrum Characteristic

Eucalyptus owns the advantages of fast-growth,yielding ability,barren-tolerance and better trunk.Its wood is big and hard,with strong corrosion resistance,and can widely be used for construction,furniture,matches,carbon materials,etc,with the high use value and economic value.In this paper,the method of sampling is successive planting.we analyzed the growth rhythm of eucalyptus plantation,soil organic carbon,physical and chemical composition of soil organic carbon,spectral characteristics of soil organic carbon,etc.The results showed:(1)Effects of repeated eucalyptus planting on soil organic carbon storage.For 0-20cm Soil organic carbon contents,first-generation eucalyptus>second-generation eucalyptus.The first-generation eucalyptus differs by 2.56g·kg-1 from the second.In terms of the 20-100cm oil organic carbon contents of all layers,second-generation eucalyptus>first-generation eucalyptus.The second-generation eucalyptus differs by 2.56g·kg-1 from the first.Although eucalyptus has some carbon sequestration capacity,due to the short rotation of eucalyptus,the deciduous leaf fails to convert the organic matter in the soil in time.Besides cleaning leaves of second generation of eucalyptus is using the method of slash buring in order that The deciduous leaves can convert into C02.Therefore with the increase generation of Eucalyptus,the content of organic carbon in soil deceases.(2)Effects of repeated eucalyptus planting on physical chemical composition of soil organic carbon.Organic carbon content in light group and heavy group of different planting generation of eucalyptus plantation and Chinese fir forest all gradually reduced along with the deepening of soil layers.Soil organic carbon content of soil aggregate gradually reduced along with the deepening of layers.The changes of active organic carbon,chronic organic carbon,inert organic carbon content are characterized by decreasing gradually with the deepening of the soil layers.(3)Effects of repeated eucalyptus planting on spectrum characteristics of soil organic carbon.The ratio of soil aliphatic carbon/aromatic carbon of different planted forests ranked in the order:cedarwood>the second generation eucalyptus,cedarwood>the first generation eucalyptus;the sequence of alkyl carbon/oxygen alkane carbon ratio was:the second generation eucalyptus>eucalyptus,the first generation eucalyptus = cedarwood;the ratio of ice carbon/hydrophilic carbon ranked in the order:the second generation eucalyptus>cedamood,the first generation eucalyptus>cedarwood.Infrared spectroscopy of four layers of soil is similar.