ABSTRACT

Fine root is a significant component in carbon (C) and nitrogen (N) dynamics in temperate forests. Winter processes affect plant growth and nutrient concentration, however, the effect of reduced snowpack on fine root remains unclear. Here, we conducted snow removal manipulation and investigated the fine root biomass and necromass, dynamics (production, mortality and disappearance) and the C and N concentrations of Quercus crispula (oak) and Sasa nipponica (Sasa), in mineral topsoil (0–10 cm) throughout 1 year. The effect of snow removal on the fine root biomass and necromass was insignificant. The effect of snow removal on the production, mortality and disappearance of fine root, and on total C and N concentrations of fine root biomass and necromass were insignificant. The fine root biomass of oak was significantly greater than that of Sasa, although the fine root necromass of Sasa was significantly greater than that of oak. Fine root necromass showed clear seasonal change, although a seasonal change of fine root biomass was unclear. Total C concentration in the fine root biomass and necromass of oak was significantly higher than that of Sasa. Total N concentration in the fine root necromass in May 2015, when after the snow removal, of Sasa was significantly higher than that of oak, in both snow removal and control plots. Our results showed that the fine root necromass of Sasa supplies more N than that of oak in spring, regardless of snowpack depth.

摘要

细根是温带森林中碳（C）和氮（N）动态的重要组成部分。冬季过程会影响植物生长和养分含量，但是，减少积雪对细根的影响尚不清楚。在这里，我们进行了除雪操作，并研究了细根生物量和坏死，动态（产量，死亡率和消失量）以及栎栎和Sasa nipponica的碳和氮浓度（Sasa），在1年的矿物表土（0-10 cm）中。除雪对细根生物量和坏死的影响微不足道。除雪对细根的产生，死亡和消失以及细根生物量和坏死总碳和氮浓度的影响均不显着。橡木的细根生物量显着大于Sasa的细根生物量，尽管Sasa的细根坏死生物量显着大于橡木。细根坏死呈明显的季节变化，尽管细根生物量的季节变化尚不清楚。橡木的细根生物量和坏死中的总C浓度显着高于Sasa。2015年5月，除雪后，Sasa的细根坏死生物中的总N浓度显着高于橡木，在除雪区和控制区中。我们的结果表明，无论雪堆的深度如何，春季萨沙的细根坏死神经都比橡木提供更多的氮。