The Response Of Fine Root Morphology And Anatomy Of Dominant Shrubs In Natural Secondary Forest To Nitrogen Deposition

The experiment of this research in the growing season,in July 2018 to Changbai mountain 12 years nitrogen?N?settlement control simulation test sample mountain in northeast of the Philadelphus schrenkii Rupr.,Acanthopanax senticosus?Rupr.Maxim.?Harms.,Syringa reticulata?Blume?h.Hara.three advantages shrub root sampling,The response of root morphological characteristics and anatomical structure to the addition of different gradient N was studied by using the root sequence method,aiming to explore the potential ecological relationship between the roots of three dominant shrubs.Three N additive gradients were set in this experiment,which were the control(CK,0 g N m^-2·a^-1),low N treatment(T_L,2.5 g N m^-2·a^-1)and high N treatment(T_H,5.0g N m^-2·a^-1).The research results are as follows:Exogenous N application significantly changed the TN and TP contents of the first five grades of the three dominant shrubs,but had no significant effect on the TOC content.In this experiment,the cortical thickness and column diameter of the first three orders of fine roots?absorbing roots?of the three shrubs decreased and increased with the addition of N.The relationship between the subcortical thickness and the number of cortical layers and cortical cell diameter was consistent when N was applied to the first three fine roots of Philadelphus schrenkii Rupr.The cortical thickness of Acanthopanax senticosus?Rupr.Maxim.?Harms.and Syringa reticulata?Blume?H.Hara.may only be due to the number of layers.We can think that the drought tolerance of the three shrubs has a gradient relationship,which can be expressed as Philadelphus schrenkii Rupr.<Acanthopanax senticosus?Rupr.Maxim.?Harms.<Syringa reticulata?Blume?H.Hara.The results showed that the fine roots of plants could make corresponding morphological and anatomical changes in order to optimize their physiological functions.There is a close relationship between the morphology and anatomy of plant fine roots,which is mainly reflected by the differences of physiological functions.Stoichiometry can explain the morphological and anatomical changes of the fine roots.