Wind erosion prevention characteristics and key influencing factors of bryophytic soil crusts

Abstract

Aims Biological soil crusts (BSCs) are generally considered to reduce wind erosion, however, the extent of reductions is highly dependent on the vegetation type, soil moisture status, and their interactions in the field. The interrelationships between these factors or their combined effects are relatively unknown. The objectives of this study were to evaluate the contributions of the crust coverage (CC), associated with the soil moisture content (SMC), and the vegetation coverage (VC) to reduce wind-erosion and to provide a basis for the effective management of BSCs.Methods We used an orthogonal design and large-scale wind tunnel simulations to determine the erosionresistance characteristics of BSCs, and the effects of soil moisture content (SMC), vegetation coverage (VC) and crust coverage (CC) on its wind erosion reductions. Results Our results showed that 1) the medium SMC+ low CC+high VC were the most effective contributors in decreasing the wind erosion modulus; 2) the high SMC+medium CC+low VC primarily reduced the sand-transport rate; 3) the medium SMC+high CC+ low VC, with the smallest aeolian sand-flow structure index, resulted in the lowest level of aeolian sand-flow saturation; 4) the high SMC+high CC+medium VC exhibited the highest threshold wind velocity; and 5) the VC and CC were found to have significant effects on the surface roughness, but the SMC did not. Conclusions BSCs should be strongly protected during dry and windy seasons in the spring and winter because of their value in reducing wind erosion. The BSC may be moderately disturbed during wet and weak wind seasons in the summer or autumn to ameliorate soil moisture conditions, especially in the sites with high vegetation coverage, without exacerbating wind erosion. Management that carefully considers the timing and disturbance of BSCs will help to determine the sustainable balance between the Bprotection^and Bdestruction^of BSCs and their effective use in reducing wind erosion.

Interactive effects of wind speed, vegetation coverage and soil moisture in controlling wind erosion in a temperate desert steppe, Inner Mongolia of China

“…Soil moisture generates tension between soil particles, reinforcing the cohesive force between particles and lowering the erodibility of the soil by wind, ultimately enhancing the resistance of soil surface to wind erosion (Han et al, 2012;Nourzadeh et al, 2013;Bu et al, 2015;Bergametti et al, 2016). Furthermore, with increasing water content, the critical friction speed increased in increments proportional to the soil moisture.…”

“…Research on wind erosion has been done by scholars at home and abroad. Factors that influence wind erosion can be summed up as vegetation status/coverage (Mendez and Buschiazzo, 2015), soil conditions (Bu et al, 2015;Bergametti et al, 2016) and wind speed (Kang et al, 2012;He et al, 2013).…”

Evaluation of wind erosion control practices at a photovoltaic power station within a sandy area of northwest, China

“…The wind erosion resistance exhibited by biocrusts is closely related to the crust development stage and the type and nature of surface conditions (Bu et al, 2015; Kheirfam & Asadzadeh,2020). The moss‐crust was in its final successional stage for this study and would have had higher photosynthesis rates, exopolysaccharide production, biological diversity, increased soil water contents, and nutrient contents (Guo, Zhao, Zhao, Zuo, & Li, ; Housman, Powers, Collins, & Belnap, 2006; Zhang et al, 2018).…”

“…Under specific wind speed conditions, the coverage and density of vegetation were negatively correlated with wind erosion such that when the vegetation coverage was less than 20%, there was substantially greater wind erosion (Li, Okin, Alvarez, & Epstein, 2007; Zhao, Zheng, & He, 2005; Dong, Fryrear, & Gao, 2000; Dong, Gao, & Fryrear, 2000). As an alternative method of wind erosion control, the rapid cultivation of biocrusts has been proven to be feasible and may be used as a practice for the short‐term restoration of impaired ecosystems (Antoninka, Bowker, Reed, & Doherty, 2016; Bu et al, 2015; Bu, Wu, Yang, & Zheng, 2014; Doherty, Antoninka, Bowker, Ayuso, & Johnson, 2015; Maestre et al, 2016). Undisturbed biocrusts were shown to inhibit wind erosion at wind speeds of 25–30 m s −1 (Wang, Zhang, Zhang, & Han, 2004).…”

Characterization of Surface Runoff Pathways and Erosion Using Hydrological Attributes Under Simulated Rainfall

“…Surface roughness is a dynamic feature that affects soil surface runoff and erosion processes (Zhao et al, 2014). It has an important effect on the way of surface runoff generation, characteristics, infiltration processes, and erosion and sediment production processes (Bu et al, 2015;Modeste et al, 2017).…”