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以25年生的杉木人工林为对象,研究了间伐对杉木1～5级根的生物量、形态和氮含量的影响.结果表明:随着根序的增加,杉木细根的生物量、直径和组织密度(RTD)显著增加,而比根长(SRL)、根长密度(RLD)和根数(RN)显著降低.间伐显著提高了1～2级根的生物量、RLD和RN,以及1级和3～5级根的RTD,而对细根的SRL和氮含量无影响;1级和3～4级根的直径显著减小;表层(0～10cm)土壤中的2级根直径明显小于亚表层(10～20cm)土壤,而1～3级根的RLD和1～2级根的RN和氮含量均大于亚表层土壤.间伐和土层的相互作用仅使1～2级根的直径减小.杉木细根的变化主要与间伐后的植被生长及更新密切相关.
The effects of thinning on the biomass, morphology and nitrogen content of Chinese fir (Cunninghamia lanceolata) 1 ~ 5 roots were studied in a 25-year-old Chinese fir plantation. The results showed that the biomass, diameter and Tissue density (RTD) increased significantly, but root length (SRL), root length density (RLD) and root number (RN) decreased significantly. Thinning significantly increased the biomass of roots 1-2, RLD and RN, And 3 ~ 5 root RTDs, but had no effect on the SRL and nitrogen contents of fine roots. The diameters of roots of grade 1 and grade 3 ~ 4 were significantly reduced. The diameter of the grade 2 roots in surface soil (0 ~ 10cm) (10 ~ 20cm) soil, while the RN and nitrogen contents of RLDs and 1 ~ 2 roots of roots 1-3 were greater than that of subsurface soil. The diameter decreases.The changes of fine roots in the fir are mainly closely related to the growth and regeneration of the thinned vegetation.