Link between the aboveground and belowground biomass allocation with growing of Tamarix sp. seedlings in the hinterland of Taklimakan Desert, China

Abstract

The morphological characteristics and biomass allocation can reflect plant adaptive strategies to the environment. Tamarix sp. is an excellent shrub species used for windbreaks and fixing sand in the desert of northwest China. The successful establishment of Tamarix sp. seedlings and their growth into mature individuals require their adaptation to various environmental conditions, which is the key to naturally regenerating the Tamarix population. To clarify the root morphological characteristics, leaf structural characters, and biomass allocation of Tamarix sp. seedlings in response to drought conditions, we took the Tamarix sp. seedlings at the Daryaboyi oasis in the hinterland of Taklimakan Desert as the object of study, analyzed rooting depth, root dry weight (RDW), specific root length (SRL), root surface area (RA), specific root area (SRA), leaf area (LA), specific leaf area (SLA) and root: shoot ratio (R:S ratio). The gravimetric soil water content varied from 5.80% to 25.84% in this study area. The taproots of Tamarix sp seedlings with small basal stem diameters were shallower and had few lateral root branches and Tamarix sp. seedlings with large basal stem diameters had more obvious taproots and lateral roots. With the growth of Tamarix sp. seedlings, the taproot deepened, and the values ranged from 4.5 cm to 108.0 cm; the SRL, SRA, and SLA decreased, and the ranges of the values were 28.92–478.79 cm·g-1, 1.07–458.50 cm2·g-1, and 24.48–50.7 cm2·g-1; the RDW, RA, and LA increased, the ranges of the values were 0.16–21.34 g, 3.42–328.04 cm2, and 2.41–694.45 cm2; the more biomass was allocated to the aboveground parts, and the mean R: S ratio was 0.76. In better soil water conditions, the root growth rate decreased as Tamarix sp. seedlings grew, and more biomass was allocated to the aboveground. This further showed that stable surface water is highly significant to the biomass allocation strategy of Tamarix sp. seedlings.

Evaluation of Soil Quality and Analysis of Barriers of Protection Forests along Tarim Desert Highway Based on a Minimum Data Set

“…Furthermore, soil quality fluctuations can ultimately be attributed to changes in external material energy inputs [3,[36][37][38]. The soil quality environment of arid zone soils after plant colonization is highly enhanced compared to the original bare soil [39][40][41][42]. A preliminary analysis of the physical, chemical, and biological indicators of soil in the protection forest has helped to clarify the current state of soil quality along the Tarim Desert Highway.…”