油松、栓皮栎幼苗种内和种间竞争对根系结构与非结构性碳水化合物的影响OA

[Objective]This study aims to compare the plasticity of root system structure and the seasonal variations of non-structure carbon in interspecific and intraspecific competition between Q.variabilis and P.tabuliformis,and elucidate the competitive mechanism in forest succession,so as to provide theoretical basis for the efficient cultivation of oak-pine mixed forests.[Method]Two-year-old seedlings of Q.variabilis and P.tabuliformis were used as research objects,and three competition scenarios of P.tabuliformis–P.tabuliformis,P.tabuliformis–Q.variabilis,and Q.variabilis–Q.variabilis were set up.Root system structural traits and non-structure carbon were measured,and the two-factor analysis of variance was used to explore the effects of competition scenarios and seasons on root system structure and non-structure carbon were explored using.[Result]Compared with intraspecific competition,the interspecific competition of P.tabuliformis–Q.variabilis inhibited the root length,root surface area,fine roots,and total root volume of P.tabuliformis seedlings,while the interspecific competition promoted the coarse root volume of Q.variabilis seedlings.The soluble sugar,starch and non-structural carbohydrate contents in fine roots and whole plant of P.tabuliformis seedlings under the P.tabuliformis–Q.variabilis interspecific competition were significantly lower than those in the P.tabuliformis intraspecific competition,while the above-mentioned indicators of Q.variabilis seedlings in the interspecific competition were basically higher than those in the Q.variabilis intraspecific competition,and the differences were even more pronounced at the end of August.[Conclusion]Q.variabilis seedlings shows stronger adaptability and competitive advantage in P.tabuliformis–Q.variabilis interspecific competition.Both species can adjust their root system structure and non-structure carbon levels seasonally to optimize their competitive strategies.These findings help to understand the succession process of P.tabuliformis–Q.variabilis mixed forests and provide theoretic basis for efficient cultivation of P.tabuliformis–Q.variabilis mixed forests.