根系分隔对杉木木荷幼苗生长与生物量的影响OA

[Objective]This study aimed to explore the interspecific underground interaction and ecological adaptation strategy in mixed plantations of Cunninghamia lanceolata and Schima superba.[Method]Based on Cunninghamia lanceolata and Schima superba,five root separation treatments were estab-lished to systematically examine the effects of root interactions on seedling growth,root development,leaf functional traits,and biomass allocation strategies of the two species.[Results](1)Compared with mono-culture,the three root separation treatments significantly increased the seedling height and basal diameter of both Cunninghamia lanceolata and Schima superba.For Cunninghamia lanceolate,seedling height in-creased by 74.40％under plastic film separation,while basal diameter increased significantly by 10.71％under the no-separation treatment.For Schima superba,seedling height and basal diameter increased by 76.94％and 29.35％,respectively,under nylon membrane separation treatment.(2)In terms of root growth,the different separation treatments significantly increased total root length,root surface area and root volume of the two tree species.Among them,the greatest increase in total root length was observed in Schima superba under nylon membrane separation,reaching 108.78％.(3)In terms of leaf functional traits,there was no significant difference in leaf length,leaf width,leaf area,leaf circumference and leaf length-width ratio of Cunninghamia lanceolata under different separation treatments,but the specific leaf area was significantly increased by 57.79％under plastic film separation treatment(P＜0.05).In Schima superba,leaf trait indices were significantly increased under plastic film separation treatment,and the leaf tissue density was the highest under monoculture in both species.(4)The three separation treatments in-creased the total biomass and organ biomass of Cunninghamia lanceolata to varying degrees.Plastic film separation treatment notably increased stem biomass and total biomass,while the non-separation treat-ment increased root biomass and leaf biomass by 33.33％and 34.04％,respectively.For Schima superba,total biomass and organ biomass followed the order:nylon membrane separation＞plastic membrane sep-aration＞root non-separation.The leaf biomass ratio of Cunninghamia lanceolate,as well as the root-shoot ratio and root biomass ratio of Schima superba,did not significantly increase under the three separa-tion treatments.(5)The interaction intensity analysis showed that when Schima superba was mixed with Cunninghamia lanceolate,the relative interaction intensity(RII)values for aboveground biomass,below-ground biomass,and total biomass were all greater than 0,indicating a facilitative effect.In contrast,for Cunninghamia lanceolata,the RII values of aboveground biomass,belowground biomass,and total bio-mass were less than 0 only under plastic film separation,indicating an inhibitory effect.Moreover,under this treatment,the RII value for belowground biomass was higher than those for aboveground biomass and total biomass.[Conclusion]Nylon mesh separation was the most effective treatment for achieving mutual benefit between Cunninghamia lanceolata and Schima superba,as it maintained the normal growth of Cunninghamia lanceolata while promoting the growth of Schima superba.In terms of ecological adapta-tion strategies,Cunninghamia lanceolata tends to be conservative,while Schima superba tends to be ac-quisitive.These findings provide a theoretical basis and material basis for the construction of mixed forests,which is of great significance for the scientific management of Cunninghamia lanceolata mixed forests.