Carbon and nitrogen allocation shifts in plants and soils along aridity and fertility gradients in grasslands of China

Abstract

Plant carbon (C) and nitrogen (N) stoichiometry play an important role in the maintenance of ecosystem structure and function. To decipher the influence of changing environment on plant C and N stoichiometry at the subcontinental scale, we studied the shoot and root C and N stoichiometry in two widely distributed and dominant genera along a 2,200‐km climatic gradient in China's grasslands. Relationships between C and N concentrations and soil climatic variables factors were studied. In contrast to previous theory, plant C concentration and C:N ratios in both shoots and roots increased with increasing soil fertility and decreased with increasing aridity. Relative N allocation shifted from soils to plants and from roots to shoots with increasing aridity. Changes in the C:N ratio were associated with changes in N concentration. Dynamics of plant C concentration and C:N ratios were mainly caused by biomass reallocation and a nutrient dilution effect in the plant‐soil system. Our results suggest that the shifted allocation of C and N to different ecosystem compartments under a changing environment may change the overall use of these elements by the plant‐soil system.

The ecological stoichiometry and interrelationship between litter and soil under seasonal snowfall in Tianshan Mountain

“…, Luo et al. ). As plants grow and develop, organic matter is produced through photosynthesis and nutrients return to the soil via litter decomposition and root exudation (Ndagurwa et al.…”

“…In terrestrial ecosystems, interactions between plants and the soil play an important role in regulating ecosystem stability (Bauer et al 2017, Luo et al 2017. As plants grow and develop, organic matter is produced through photosynthesis and nutrients return to the soil via litter decomposition and root exudation (Ndagurwa et al 2015).…”

Trait correlation network analysis identifies biomass allocation traits and stem specific length as hub traits in herbaceous perennial plants

“…Plant organs perform different functions: roots take up resources from the soil and anchor the plants, rhizomes ensure resource storage and vegetative regeneration, stems provide support and hydraulic pathways, leaves gain carbon via photosynthesis, and seeds provide generative reproduction. Plants adjust allocation of carbon and nutrients between their organs so that these functions ensure the persistence of the species in their particular habitat (Luo et al, ; Minden & Kleyer, ). Plant traits such as organ mass, form, density, surface area, volume, and chemical composition, among others, may reflect this coordinated allocation (Kleyer & Minden, ; Kramer‐Walter & Laughlin, ).…”

Untitled

“…Plant C and soil organic carbon are in active exchange with the atmosphere and small changes in soil organic C stocks could have severe impacts on the global C cycle (Knops et al, 2009;Wen-Jie et al, 2011;Cong et al, 2014;Walter et al, 2016;Luo et al, 2017). In general, only a few features have been considered, such as the microbiological contribution to the carbon cycle (Egli et al, 2006;Bardgett et al, 2007;He & Tang, 2008;Mavris et al, 2010;Dümig et al, 2011;Guelland et al, 2012;Kabala & Zapart, 2012;Chae et al, 2016).…”

“…In scenario 1, we hypothesize that soil evolution is more relevant for the fluxes than vegetation characteristics. Plant C and soil organic C are in active exchange with the atmosphere and small changes in soil organic C stocks could have severe impacts on the global C cycle (Knops et al, 2009;Wen-Jie et al, 2011;Cong et al, 2014;Walter et al, 2016;Luo et al, 2017). In addition, documented evidences revealed that the amount of nitrogen present in the soil and in the vegetation is strongly linked to ecosystem fluxes (Field & Mooney, 1983;Reich et al, 2006;Xia et al, 2009;Huff et al, 2015;Wang et al, 2015;Peng et al, 2017;Song et al, 2017;Tanga et al, 2018).…”