Biological soil crusts increase stability and invasion resistance of desert revegetation communities in northern China

Abstract

Biological soil crusts (BSCs) in arid region provide critical ecosystem services. However, most previous studies on BSC–plant topic have had a narrow spatiotemporal and taxonomic focus, so context dependency concerning exotic plant responses to BSCs remains poorly understood. In this study, using a series of manipulative experiments under greenhouse conditions, we investigated the influence of BSCs in the Tengger Desert in northern China on seed germination and seedling growth of an exotic grass species, Stipa glareosa P. Smirn., with or without two native plants species, Eragrostis poaeoides Beauv. and Artemisia capillaris Thunb., both of whose ontogeny differs from that of the exotic species. BSC treatments included intact crusts, disturbed crusts, and bare soil. Compared to bare soil, the presence of BSCs reduced the germination of E. poaeoides and A. capillaris by 78% and 74%, respectively. For the exotic species, BSCs reduced the germination percentage by as much as 90%. With gradual increases in soil nutrients such as organic carbon, available phosphorus, and available nitrogen, the shoot biomass of the three plants increased along the sequence from bare soil to lichens and mosses. Shoot biomass of the two native plant species was reduced by the exotic species S. glareosa. The percent germination and shoot biomass of S. glareosa on the disturbed crusts were greater than those on the intact crusts and bare soils. Overall, the presence of BSCs on stabilized sand dunes can reduce the germination of these three plant species, but compared with native plant species, BSCs have a stronger inhibitory effect on the seed germination of the exotic plant species. However, the disturbance may weaken the inhibition of the seed germination of the exotic grass S. glareosa and may provide more nutrients for the exotic grass S. glareosa to establish a revegetation region. We concluded that compared with the absence of BSCs, BSCs in this desert ecosystem can provide more nutrients and a suitable environment for native vascular plants and exert an inhibitory effect on the exotic plants.

Effects of Biological Crust on Soil Properties under Different Karst Rocky Desertification Habitats

“…5). Previous studies have shown that there are differences in the ecological functions and ecological benefits of different types of BSCs because of the differentiated morphological functions and varied components [17]. In this study, the total nitrogen, available nitrogen, total phosphorus, available phosphorus, available potassium, soil organic carbon, soil bulk density, soil field water holding capacity and soil porosity under the coverage of BSCs manifest as moss crust>mixed crust>lichen crust>algae crust (P<0.05) (Fig.…”

Dynamics of phoD- and gcd-Harboring Microbial Communities Across an Age Sequence of Biological Soil Crusts Under Sand-Fixation Plantation

“…Given that P adsorption in arid or semiarid soils is generally slow, most of the retained or residual-P, which are insoluble in chemical extractors such as HCl, NaOH, H 2 O, or NaHCO 3 , also accounted for high proportions. The formation and development of BSCs on surface soil inevitably alters soil microenvironments, thereby increasing the number of soil organisms (Song et al, 2020). Some studies have used phoD and/or gcd as major molecular markers of P-transformation microbes, and the variations in their abundance can represent the tendency of soil P-transformation (Chen et al, 2017;Luo et al, 2017;Li et al, 2019b;Hu et al, 2020).…”

“…The development of BSC in these regions is affected mainly by vegetation cover, soil properties, and the interaction between organisms and soil (Hawkes, 2003). BSCs have important roles in desert ecosystems, such as in stabilizing the sand surface (Song et al, 2020), mitigating wind erosion (Zhao et al, 2011), facilitating water infiltration (Guan et al, 2019(Guan et al, , 2021, enhancing soil fertility by fixing carbon and nitrogen, increasing the availability of nutrients for vascular plants (Zhang et al, 2014a;Morillas and Gallardo, 2015), and promoting the stabilization of sand dunes (Zhao et al, 2020a). In recent years, the nutrient cycling functions of microbes in BSCs have received much research attention (Zhang et al, 2014b;Morillas and Gallardo, 2015;Zhao et al, 2020b).…”

The Role of Cryptogams in Soil Property Regulation and Vascular Plant Regeneration: A Review

“…This involves the influence of cryptogam on non-rainfall water input, evaporation, soil infiltration capacity, water-holding capacity, water diffusion capacity, and water absorption capacity. In most cases, soils covered with cryptogams have higher fertility, such as OM [14,15], TOC [16,17], TN [18,19], TP [20,21], and TK [22,23], not to mention higher nutrient availability [24][25][26][27]. However, it has also been found that lichen leads to a decrease in soil OM content [28], moss reduces the availability of soil N [29], and moss crust leads to a reduction in phosphorus available [14].…”

“…The allelopathy of cryptogam plants refers to the effect of their secondary metabolites on seed germination and seedling growth in vascular plants [36]. Soil water content, nutrient content, and soil temperature have important effects on seed germination and seedling growth of vascular plants [26,37]. However, cryptogam often leads to changes in soil moisture [10], nutrient [17] content, and soil temperature [38], indirectly affecting the regeneration of vascular plants.…”