Studies On The Compositions And Seasonal Dynamics Of Soil Soluble Organic Nitrogen In Different Tea Plantations

In this study,the object was based on the subtropical tea ecosystem with the samesoil parent material(granite) and soil type(redsoil) of two different varieties tea plantations(HuangDan and FuYun6) in Fujian. We carried out the soil SON composition andits seasonal dynamic change of the different varieties tea ecosystem in subtropical,aimed to improve on understanding tea ecosystem soil characteristics of SON and revealits importance to tea ecosystem nitrogen ciculation in rats.1The concentrations of soilTFAA in Huandan and Fuyun6on0-15cm layer were higher2.55and3.25mg/kg than the corresponding15-30cm layer;TFAA/SON were higher4.46%and7.69%than15-30cm.,and the concentration of OSON on0-15cm were higher1.67and4.22mg/kg than15-30cm,respectively.T-test results showed that the concentration of TFAA、OSON of Huangdan respectively were no significant difference between two layers.,whileFuyun6were on significant level;Huangdan OSON were no significant difference betweentwo layers,while Fuyun6were highly significant diffrence.2Different varieties of TFAA、TFAA/SON、OSON in0-15cm layer showed Huangdan>Fuyun6,and was higher than Fuyun6above3.49mg/kg、17.53%and3.59%,respect-ively.but OSON/SON of Fuyun6were higher6.53mg/kg than Huangdan,The concent-rations of TFAA between Huangdan and Fuyun6were highly significant difference,but TFAA/SON、SON、OSON/SON between two types of tea garden were all no significant difference.Different varieties of FTAA、TFAA/SON、OSON in15-30cm layeralso showed that Huang Dan>Fuyun6,and the concentrations of TFAA between Huang dan and Fuyun6were highly significant difference,but the concentrations of TFAA/SON、SON、OSON/SON were no significant difference.3Free amino acid in the soil of Huangdan and Fuyun6consisted of neutral amino acid andacidic amino acid. In0-15cm layer of Huangdan and Fuyun6, the neutral amino acid both hadthe highest content,respectively accounting for85.20%and80.54%of total amino acidcontent;Acidic amino acid content was the second one,and then Basic amino acid and sulfuramino acid had the lowest content,and acidic amino acid and basic amino acid didn’t reachsignificant difference level beween two tea genotypes,while the neutral amino acid and sulfuramino acid reached significant or highly significant difference level; In15-30cm soil of Huangdan and Fuyun6, the neutral amino acid also had the highest content,respectivelyaccounting for84.65%and84.05%of total amino acid content;Acidic amino acid content wasalso the second one,and the last were Basic amino acid and sulfur amino acid content, and theacidic, alkaline, neutral and sulfur amino acid between Huangdan and Fuyun6reachedsignificant or highly significant difference level.4SON content in the soil of Huangdan and Fuyun6both showed highest in summer andlowest in spring,and the seasonal dynamics of them basically had an N shape. SON content inthe soil of the two tea gardens reached significant or highly significant difference levelbetween the seasons of spring and summer,and between spring and winter,but there were nosignificant differences between summer and winter,or between spring and autumn. SONcontent in0-15cm layer of Huangdan is much higher than that of Fuyun6,but there were nosignificant differences between the soil of the two tea gardens. SON content in15-30cm layerof Huangdan was higher than that of Fuyun6in all of the four seasons,but there were nosignificant differences between the seasons of the two tea genotypes except for summer andwinter,with highly significant difference level.