Climate and shrubs at different scales jointly drive the changing pattern of moss crust soil multifunctionality in a temperate desert

Background and aims

In desert ecosystems, moss crusts, along with shrubs, often form mosaic spatial patterns. However, it is unclear how microhabitats formed by shrubs and the regional climate will affect soil multifunctionality (i.e., the capacity of soils to conduct multiple functions such as carbon sequestration and nutrient conversion; SMF) and what the key factors influencing it are.

Methods

Moss crust soils were collected from under shrubs canopy and in exposed areas along a climatic gradient in the Gurbantungut Desert. We carefully analyzed the variation patterns of the moss crust SMF across different scales by measuring soil nutrients and enzyme activities. Meanwhile, we explored the carbon-related SMF(C-SMF), nitrogen-related SMF(N-SMF), and phosphorus-related SMF(P-SMF).

Results

At the microhabitat scale, shrubs increased the C-SMF, N-SMF, and SMF of moss crusts. Meanwhile, at the regional scale, with increases in precipitation or decreases in temperature, the C-SMF, N-SMF, P-SMF, and SMF of moss crusts under shrubs showed a decreasing trend, whereas the change in exposed areas was smoother. Decreases in precipitation had a positive effect on SMF and enhanced the “shrub effect”. Hierarchical partitioning analysis showed that climate was relatively more important for moss crust SMF, accounting for 68.10% of the total contribution rate, while the effect of shrub accounted for 19.40%.

Conclusions

There are close relationships between climatic factors, shrubs, and moss crust SMFs, and it is important to consider driving factors at different scales simultaneously when exploring the mechanisms of changes in ecosystem functions.