Contrasting response of coexisting plant's water-use patterns to experimental precipitation manipulation in an alpine grassland community of Qinghai Lake watershed, China

• Published in: PloS one 2018-04, Vol.13 (4), p.e0194242-e0194242
• Main Authors: Wu, Huawu, Li, Jing, Li, Xiao-Yan, He, Bin, Liu, Jinzhao, Jiang, Zhiyun, Zhang, Cicheng
• Format: Article
• Language: English
• Subjects: Allium - growth & development; Allium - metabolism; Alpine climates; Alpine environments; Biodiversity; Biology and Life Sciences; China; Climate; Climate change; Communities; Deuterium - analysis; Drought; Droughts; Earth Sciences; Ecology; Ecology and Environmental Sciences; Ecosystem biology; Ecosystems; Environmental changes; Flowers & plants; Future climates; Geography; Grassland; Grasslands; Irrigation; Laboratories; Lakes; Leaf water potential; Leaves; Limnology; Moisture content; Oxygen Isotopes - analysis; Physiological aspects; Plant growth; Plant Leaves - chemistry; Poaceae - growth & development; Poaceae - metabolism; Precipitation; Rain; Rainfall; Seasonal variations; Seasons; Soil - chemistry; Soil layers; Soil moisture; Soil water; Studies; Summer; Tourism; Vegetation; Water - chemistry; Water - metabolism; Water content; Water depth; Water potential; Water use; Watersheds
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0194242

Understanding species-specific changes in water-use patterns under recent climate scenarios is necessary to predict accurately the responses of seasonally dry ecosystems to future climate. In this study, we conducted a precipitation manipulation experiment to investigate the changes in water-use patterns of two coexisting species (Achnatherum splendens and Allium tanguticum) to alterations in soil water content (SWC) resulting from increased and decreased rainfall treatments. The results showed that the leaf water potential (Ψ) of A. splendens and A. tanguticum responded to changes in shallow and middle SWC at both the control and treatment plots. However, A. splendens proportionally extracted water from the shallow soil layer (0-10cm) when it was available but shifted to absorbing deep soil water (30-60 cm) during drought. By contrast, the A. tanguticum did not differ significantly in uptake depth between treatment and control plots but entirely depended on water from shallow soil layers. The flexible water-use patterns of A.splendens may be a key factor facilitating its dominance and it better acclimates the recent climate change in the alpine grassland community around Qinghai Lake.