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In the temperate grasslands of northern China, there exists a large range of soil texture. However, previous studies have mainly focused on the effect of climate water deficit on plant traits and have paid little attention to the effect of soil water deficit because grasses tend to use rainfall water directly. We measured eight drought‐related plant traits of 12 widely distributed perennial species in the temperate grassland in northern China and examined drought‐related plant traits under different aridity index ([ET0 − P]/ET0) and soil sand/clay ratio. The 12 species were categorized into three functional groups: fibrous‐rooted C4 species, fibrous‐rooted C3 species, and tap‐rooted C3 species. Our results showed that increasing climate drought had influence on all selected functional groups, and the influence on aboveground biomass and height was especially large on fibrous‐rooted C3 species. Coarse soil led to increased root length of fibrous‐rooted C3 and tap‐rooted C3 species. Our results imply that root system can be important to plant responses under drought, and soil texture can have influence on plant, though most of the traits show resistance to coarser soil. [ABSTRACT FROM AUTHOR]

• Drought responses were measured for grass species on loamy and sandy soils. • Sandy soil is beneficial for plant growth but harmful for plant drought resistance. • Fibrous-rooted species might provide a buffer against drought in loamy soil. • Degraded grasslands with coarser soil might be more sensitive to drought. Grassland degradation is often accompanied by coarsened soil, which could change water and nutrient uptake by plant roots. Studying the effects of soil coarsening on species performance with different root systems under manipulated irrigation has important practical significance in grassland restoration under changing climate. We conducted a common garden experiment with three water treatments (control, drought stressed and water addition) and two soil texture (loamy soil which is fine and sandy soil which is coarse) under a rainout shelter to explore the effects of degradation on the growth and drought response of tap-rooted species and fibrous-rooted species. Three fibrous-rooted species (Setaira viridis , Cleistogenes squarrosa and Leymus chinensis) and three tap-rooted species (Medicago ruthenica , Artemisia frigida and Potentilla bifurca) were used in the study (P. bifurca failed to germinate). The results showed that three of the five selected species tended to have higher aboveground biomass, greater belowground biomass, larger height and longer root length in sandy soil than in loamy soil. For fibrous-rooted species, drought had negative influence on several plant traits in sandy soil, and had no influence on plant traits in loamy soil. For tap-rooted species, drought had negative influence on plant traits both in loamy soil and in sandy soil, and the influence was larger in loamy soil than in sandy soil. The results showed that loamy soil might provide a buffer against drought for fibrous-rooted species, but make tap-rooted species more sensitive to drought. Our results implied that degraded grasslands with coarsened soil might change community composition in the grassland, making tap-rooted species take the place of fibrous-rooted species. Thus, soil coarsening is an important factor in predicting drought resistance as well as composition of the community, and should be given more attention under future climate changes. [ABSTRACT FROM AUTHOR]