Vertical patterns of fine root biomass, morphology and nitrogen concentration in a subalpine fir-wave forest

Abstract

To clarify the nutrient acquisition strategies for below-ground resources in a subalpine Abies forest with shallow soils, we examined the vertical patterns of fine root biomass, morphology, nitrogen concentration of fine root tissue and soil chemical characteristics in nine quadrats of sapling, young and mature stands in a subalpine fir-wave forest, central Japan. The community characteristics changed with stand development, but stand development did not influence the vertical pattern of fine root characteristics. Fine root biomass decreased with soil depth. Specific root length did not differ among soil depths, and neither average diameter nor tissue density of fine roots changed vertically. The nitrogen concentration of fine roots differed significantly among soil depths, and was higher in surface soils than in deeper soils. Moreover, soil pH, soil electrical conductivity and soil nitrogen concentration were higher in surface layers than deeper layers. Therefore, we suggest that the subalpine Abies community has a nutrient acquisition strategy that allows uptake of more nutrients near the surface in shallow soils due to the larger investment in biomass and more active metabolism, but not due to phenotypic plasticity in fine root morphology. In addition, we observed that fine root biomass changed with stand development, where specific root length was greater in sapling stands than in older stands.

Effect of Stand Age on Fine Root Biomass, Production and Morphology in Chinese Fir Plantations in Subtropical China

“…In the Chinese fir plantation, the SRL remained relatively stable. In contrast, root tissue density, which was considered as an indicator for root functional status [48], showed high variations. The root tissue density increased consistently with stand age.…”

Dynamic characteristics of soil properties in a Robinia pseudoacacia vegetation and coastal eco-restoration

“…In this paper, soil nutrient decreased with the increase of soil depth. High nutrient availability made fine roots concentrate in the soil surface layer (Ugawa et al, 2010), which would impact enzyme activities and microorganism distribution pattern in the soil.…”

Temporal variations of biomass, carbon and nitrogen of roots under different tree species

“…As also mentioned in the root carbon section, fine roots have fresh and young matter with less lignin, and less carbon content can be decomposed easily by increasing the C/N ratio. Similarly, Dicus and Dean (1999) and Ugawa et al (2010) indicated the importance of the nitrogen concentration of fine roots. Interestingly, Ugawa et al (2010) and Noguchi et al (2005) reported that the nitrogen concentration of fine roots and root biomass was higher in surface soils than deep soil layers.…”

“…Similarly, Dicus and Dean (1999) and Ugawa et al (2010) indicated the importance of the nitrogen concentration of fine roots. Interestingly, Ugawa et al (2010) and Noguchi et al (2005) reported that the nitrogen concentration of fine roots and root biomass was higher in surface soils than deep soil layers. We detected the similar result as Ugawa et al (2010) and Noguchi et al (2005) reported, respectively.…”