Effects of Tree Species on Moso Bamboo (Phyllostachys edulis (Carriere) J. Houzeau) Fine Root Morphology, Biomass, and Soil Properties in Bamboo–Broadleaf Mixed Forests

Abstract

Understanding fine root characteristics in relation to soil properties of bamboo–broadleaf mixed forests may help optimize belowground production management and ecological functions in mixed-forest ecosystems. In this study, we compared four different bamboo–broadleaf mixed forests: Castanopsis chinensis (Sprengel) Hance with moso bamboo (CCB), Alniphyllum fortunei (Hemsl.) Makino with moso bamboo (AFB), Choerospondias axillaris (Roxb.) Burtt and Hill with moso bamboo (CAB), and Castanopsis fargesii Franch with moso bamboo (CFB), and analyzed their effects on the traits of fine roots of moso bamboo, soil nutrient contents, and enzyme activities. In January 2022, fine root and soil samples from four different mixed bamboo–broadleaf forests were collected from a subtropical region of Fujian Province, China. Results showed that CAB significantly increased fine root biomass (FRB) and root length density (RLD); however, specific root length (SRL) was only in the 0–20 cm soil layer. Specific surface area (SSA) was significantly reduced in the CCB in the 0–20 cm and 20–40 cm soil layers. The total phosphorous (TP) and total potassium (TK) contents of AFB and CAB were significantly increased (p < 0.05), and the alkali-hydrolyzable nitrogen (AN) content was significantly increased by CCB in the 0–20 cm soil layer (p < 0.05). Additionally, CFB increased the activities of acid phosphatase (ACP) and catalase (CAT) but decreased the activity of sucrase (SC). Principal component analysis showed that fine root traits (FRB, RLD, SRL, and SSA) were not only positively associated with soil organic carbon (SOC), total nitrogen (TN) and available potassium (AK) but also associated with urease (UE) and CAT. Therefore, belowground interactions between different species have a significant impact on the characteristics of fine roots and soil in bamboo–broadleaf mixed forests.

The Effect of Balanced N, P and K Fertilization on Fine Root Traits and Soil Properties in Sapindus mukorossi

“…And the fine root morphology all showed strong correlation with soil nutrients. It is suggested that the morpho-plasticity is largely affected by soil nutrient heterogeneity, which is the same as the related research results of many scholars [4,9,70,71]. This study thus clarifies that for subtropical woody plants, soil AP is the main factor driving root trait variation.…”

“…In this study, it was found that FRB, RLD and RAD under different fertilization treatments showed a decreasing pattern with the increase in soil depth, and the fine root biomass of Sapindus mukorossi was significantly reduced by 25.39%-63.01% in the soil layer of 20-40 cm, compared to 0-20 cm. It indicates that the fine roots of Sapindus mukorossi were mainly distributed in the top soil layer and, similarly, other tree species such as poplar (Populus), moso bamboo (Phyllostachys edulis) and pomelo (Citrus maxima) have similar results [4,14,32]. The topsoil layer is the main provider of nutrients for plant roots [10].…”

“…And then, we oven-dried the roots at 65 • C to a constant weight to calculate fine roots dry mass (RDM, g). Specific root length (FSRL, cm.g −1 ), root length density (RLD, cm.cm −3 ), fine root biomass (FRB, mg.cm −3 ) and average diameter (RAD, mm) were calculated using the following formulas [4,32]:…”

“…Plants can take up soil nutrients via fine roots and adjust their nutrient uptake strategies accordingly, especially when there is below-ground competition between species for soil resources. Fine root traits determine a plant's ability to absorb nutrients, such as adaptation to the environment through changes in the allocation and morphology of fine root biomass, which are key indicators of plant growth to ensure survival [4]. FRB, SRL, RAD, RLD and other indicators reflect both the morphological structure of the root system and the role of roots in nutrient uptake, transportation and other functions [5][6][7].…”

Comparative study of urea-15N fate in pure bamboo and bamboo-broadleaf mixed forests

“…For example, research indicated that when the intercropping ratio of moso bamboo and broadleaved trees was in the range of 20-30%, optimal soil nutrients were achieved, leading to the best growth performance of moso bamboo (Zhang et al, 2020a). Similarly, The intercropping of Q. tumidinoda with other tree species had a certain impact on the growth of the bamboo forest, and the extent of this impact depended on the choice of tree species (Zhou et al, 2016).…”