Potential Turnover Differences In Soil Amino Acids From Forests Typical Of Maoer Mountain

Amino acids are an important component of nitrogen conversion and migration in soil.The study of the influence of forest type and soil layer on amino acid turnover is rare,and the turnover difference of different nature amino acids in soil is still very unclear.In the context of global change,the nitrogen cycle system cannot be fully constructed.Therefore,this study adopts the method of indoor culture,in Heilongjiang province shangzhi,northeast forestry university Maoer mountain forest ecosystem positioning station selected 5 in different woodland: Larix olgensis,Pinus koraiensis,Betula platyphylla,Quercus mongolica,Betula platyphylla + Pinus koraiensis +Acer mono,to the soil add acid,neutral,alkaline three kinds of amino acid,research forest,soil layer and amino acid properties of soil amino acid turnover,reveals the potential variation and characteristics,to improve the forest ecosystem soil amino acid turnover,improve the utilization rate of forest nitrogen to provide certain reference.The study results are as follows:(1)The amino acid turnover rate was fast,and the content was decreased with the extension of time.Different amino acid turnover rate is different,and have different embodiment in different forest types,the soil layer also affects the turnover rate of amino acids to different degrees.In different forests with the same amino acid and the same soil layer,the turnover rate of broad-leaved forest is faster than that of coniferous forest,and the turnover rate of needle and broad-leaved mixed forest tends to be between the two.The turnover rate of the same amino acids in different soil layers of the same forest type shows that surface soil is better than deep soil.In the same soil layer of the same forest type,glutamate turns the fastest,followed by alanine,and lysine is at a disadvantage.(2)Amino acids are involved in amination and nitrification in soil and are mineralized to ammonium and nitrate.The increase in ammonium content was higher than that in nitrate.After the addition of amino acids of different properties,the content of soil ammonium nitrogen and nitrate nitrogen increased greatly,and the increase amount was different due to the different forest type and soil layer.In different forest types,broad-leaved forest soil has the strongest effect of promoting amino acid conversion to ammonium nitrogen and nitrate nitrogen,and then broad-leaved mixed forest is better than coniferous forest.Under the treatment of different amino acids in the same forest type,the increase of ammonium nitrogen was manifested as acidic amino acids > neutral amino acids > basic amino acids.However,the increase of nitrate nitrogen content and the increase of ammonium nitrogen showed the opposite trend,that is,the increase of nitrate nitrogen content increased successively after the addition of acidic,neutral to basic amino acids.(3)In different forest types and soil layers,the net amination and nitrification rates of amino acids were first increased,then slowly decreased,and both were positive.The maximum rate of net ammonification and nitrification of different forest types showed consistent patterns in the three soil layers,which were broad-leaved forest > mixed forest > coniferous forest.