Relationships between Artemisia ordosica communities and environmental factors following sand-dune stabilization in the Mu Us desert, northwest China

Abstract

Artemisia ordosica is an excellent sand-fixing shrub for sand stabilization in northwestern China. Sand dune stabilization, a critically important process, leads changes in abiotic factors, such as soil structure and nutrient contents. However, the effects of factors on an A. ordosica community following sand stabilization remain unclear. In this study, we used canonical correspondence analysis (CCA) to examine the relationships between A. ordosica communities and environmental factors at three habitats: semi-fixed dune (SF), fixed dune with low-coverage biological soil crust (F), and fixed dune with highcoverage biological soil crust (FC) in Mu Us desert. The mean height and coverage of plants increased with sand stabilization, while species diversity and richness increased initially and then reduced significantly. Correlation analysis and CCA revealed that slope, soil organic carbon, and nutrient contents, proportion of fine soil particles, soil moisture, and thickness of biological soil crust were all highly correlated with vegetation characteristics. These environmental factors could explain 40.42 % of the vegetation-environment relationships at the three habitats. The distribution of plant species was positively related to soil moisture in the SF dune. Soil moisture, soil nutrient, and fine-particle contents mainly affected plants distribution in the F dune. In the FC dune, distribution of plant species was positively and negatively correlated with the thickness of biological soil crust and soil moisture at a depth 0-20 cm, respectively. The dominance value of typical steppe species increased significantly following sand-dune stabilization and relations between species and samples in CCA ordination bi-plots showed that perennial grasses could invade the A. ordosica community on FC, indicating A. ordosica communities had a tendency to change into typical steppe vegetation with the further fixation. We conclude that the significant differentiation not only occurred in community characteristics, but also in the relationships between vegetation and environmental factors among the three stages of dune fixation. So, restoration of degraded dune ecosystems should be based on habitat conditions and ecological needs.

Benefactor facilitation and beneficiary feedback effects drive shrub‐dominated community succession in a semi‐arid dune ecosystem

“…In the most disturbed conditions, A. ordosica is likely efficient for shelter from wind erosion and for sand fixation (Fan et al. ). At this stage, A. ordosica prefers to quickly increase its shrub canopy coverage (Li et al., ).…”

Biochar and compost amendments alter the structure of the soil fungal network in a karst mountainous area

“…Soil pH was determined in a soil suspension at a soil:water ratio of 1:2.5 (w/v) using a pH meter (Metro-pH 320; Mettler-Toledo Instruments Ltd., Shanghai, China). Soil organic carbon (SOC) was measured by the potassium dichromate oxidation-external heating method (Fan et al, 2017). Soil available nitrogen (AN) was measured by the alkali solution diffusion method (Webster, 2008).…”

Sand dune stabilization changes the vegetation characteristics and soil seed bank and their correlations with environmental factors

“…Sand dune mobility in desert ecosystems reflects the underlying ecological processes, including biotic interactions, seed dispersal, vegetation succession, and environmental change (Fan et al, 2017;Hao et al, 2017). Population pattern in sand dunes is a result of long term interactions between living vegetation and seed bank as well as their relationships with the environment (Zhang et al, 2015).…”