High nutrient uptake efficiency and high water use efficiency facilitate the spread of Stellera chamaejasme L. in degraded grasslands

Abstract

BackgroundStellera chamaejasme L. is a poisonous plant widely distributes in degraded grasslands in China. The mechanism underlying its spread remains unknown. In some degraded grasslands, S. chamaejasme has gradually replaced previous dominant species, such as Leymus chinensis, Stipa krylovii, Artemisia eriopoda on typical steppes. Apart from its unpalatability by livestock, we hypothesized that the survival strategy (nutrient uptake and water use efficiency) of S. chamaejasme in degraded grasslands could be distinct from other coexisting species in the community. Recently, ecological stoichiometry has been suggested as a new approach for studying the demand for natural resources of plants in a changing world, and the leaf carbon isotopic composition (δ13C leaf) as a rapid and effective high throughput phenotyping method for water use efficiency (WUE), both of which can reveal the survival and adaptive strategies of plants. Therefore, in this study we aimed to fill the knowledge gap concerning ecological stoichiometry in the leaf, stem, and root of S. chamaejasme and its surrounding soil on grasslands with different degrees of degradation, and comparing the leaf nutrient content and δ13C of S. chamaejasme with the coexisting species (L. chinensis, S. krylovii, A. eriopoda) in the communities. Toward this goal, we conducted a field survey in which plants and soils were sampled from four different degraded grasslands on typical steppes in China.ResultsOur results showed that there is no significant difference of carbon content (C%) and nitrogen content (N%) in leaves of S. chamaejasme in different degraded grasslands, and all element contents and element ratios in stems did not differ significantly. Meanwhile, ecological stoichiometry of S. chamaejasme is distinct from the coexisting species, with low C%, high N% and phosphorus content (P%) in the leaf, indicating high nutrient uptake efficiency of S. chamaejasme in nutrient-poor environments like degraded grasslands. Additionally, S. chamaejasme showed significant higher WUE than other species.ConclusionsOur results indicated that high nutrient uptake efficiency and high WUE of S. chamaejasme might together contribute to the spread of S. chamaejasme in degraded grasslands.

Leaf Elemental Stoichiometry of Stellera Chamaejasme L. in Response to Environmental Factors in Degraded Grasslands Across Northern China

“…Generally, it is not uncommon that using N:P ratios of plant biomass as indicators of N or P limitation in various studies (Koerselman and Meuleman 1996;Tessier and Raynal 2003). The low N/P ratio in S. chamaejasme might imply that its growth is restricted by N, which was consistent with the results reported by Guo et al (2019).…”

“…Indeed, the stoichiometric homeostasis of plants varied with species, growth stages, and element types (Peng et al 2016;Yan et al 2016;Yu et al 2011Yu et al , 2015. Stellera chamaejasme L., a toxic perennial weed, has been established and is now abundant in the alpine meadow on the eastern Tibetan Plateau and typical steppe on eastern Inner Mongolia Plateau of China (Sun et al 2009; Guo et al 2019). It has become one of the most serious weeds threatening a wide range of grasslands (Liu et al 2004).…”

“…It has become one of the most serious weeds threatening a wide range of grasslands (Liu et al 2004). Much attention has been given to S. chamaejasme because of its potential hazards on the grassland ecological safety and its impact on animal husbandry sustainability Jin et al 2018;Guo et al 2019;He et al 2019;Ma et al 2020). Despite this, no similar phylogeographical study had ever been conducted on S. chamaejasme.…”

“…Despite this, no similar phylogeographical study had ever been conducted on S. chamaejasme. Plant nutrient and stoichiometry are key foliar traits with great ecological importance, but existing publications provide limited insight into biogeographic leaf nutrient and stoichiometry patterns for S. chamaejasme (Guo et al 2019;Sun et al 2009). As habitat heterogeneity tends to increase with geographical distance, wide-ranging species can usually use a wide array of resources and tolerate broad environmental conditions or physiological stresses and ourish over a larger area (Geng et al 2011;Zhang et al 2013).…”

Soil Microbial Differences under Unpalatable Stellera Chamaejasme and Neighboring Palatable Elymus Nutans in Alpine Meadows

“…The differences in soil properties (Table 2 and Fig. 2), litter decomposition (Hobbie, 2015), together with different quantity and quality of root exudations (Sun et al, 2009;Guo et al, 2019;Brunel et al, 2019) are likely the reasons for the different soil microbial community found in Stellera patches. The alpha diversity indices and the rarefaction analysis (Fig.…”