毛竹向杉木林扩展过程中细根适应策略

毛竹向周边系统扩展的能力很强,研究毛竹扩展过程中细根的适应策略,可以为毛竹林扩展调控提供科学依掘。本研究以毛竹-杉木林扩展界面为对象,分析了毛竹不同扩展阶段细根生物量,根长密度、比根长及细根养分含量和比值的变化。结果表明:随着毛竹扩展,细根生物量和根长密度增加,比根长﹑细根N和Р含量降低;与扩展前期相比,扩展后期细根生物量,根长密度分别是扩展前期的7.03,1.57倍,分别为1683.04±188.17 g · m2和6483.14±846.82 m · m*;比根长从扩展前期的2.61±0.20 m · g'降低到到扩展后期的0.70±0.06 m ·g'.扩展前期是扩展后期的3.73倍:细根N含量从扩展前期的5.06 g· kg '降低到扩展后期的2.98 g·kg ',降低了41.11%;P含量从扩展前期的0.30 g·kg'降低到扩展后期的0.17g · kg -,降低了43.33%。

Moso bamboo exhibits a strong capacity to expand into adjacent ecosystems. Investigating the adaptive strategies of fine roots during its expansion process can provide scientific underpinnings for the regulation of Moso bamboo forest expansion. This study selected the expansion boundary between Moso bamboo and Chinese fir forests as the research target, and analyzed the variations in fine root biomass, root length density, specific root length, fine root nutrient concentrations and their ratios across different expansion stages of Moso bamboo. The results demonstrated that with the progression of Moso bamboo expansion, fine root biomass and root length density increased, while specific root length, fine root nitrogen (N) and phosphorus (P) concentrations decreased. Compared with the early expansion stage, the fine root biomass and root length density in the late expansion stage were 7.03-fold and 1.57-fold of those in the early stage, respectively, reaching 1683.04 ± 188.17 g·m⁻² and 6483.14 ± 846.82 m·m⁻². The specific root length decreased from 2.61 ± 0.20 m·g⁻¹ in the early expansion stage to 0.70 ± 0.06 m·g⁻¹ in the late stage, with the early stage being 3.73 times that of the late stage. The fine root N concentration decreased from 5.06 g·kg⁻¹ in the early expansion stage to 2.98 g·kg⁻¹ in the late stage, representing a 41.11% reduction; the P concentration decreased from 0.30 g·kg⁻¹ to 0.17 g·kg⁻¹, corresponding to a 43.33% reduction.