Groundwater controls on vegetation composition and patterning in mountain meadows

摘要: [1] Mountain meadows are groundwater-dependent ecosystems that hot spots of biodiversity and productivity. In the Sierra Nevada mountains California, these rely on shallow groundwater to support their vegetation communities during dry summer growing season in region's Mediterranean montane climate. Vegetation composition this environment is influenced by both (1) oxygen stress occurs when portions root zone saturated anaerobic conditions limit respiration (2) water table drops becomes limited. A spatially distributed watershed model explicitly accounts for snowmelt processes was linked a fine-resolution flow Tuolumne Meadows Yosemite National Park, simulate dynamics. This hydrologic calibrated observations from well observation network 2006–2009. survey also conducted at site which three dominant species were identified more than 200 plots across meadow. Nonparametric multiplicative regression performed create select best models predicting dominance basis simulated regime. The niches types representing wet, moist, meadow found be described using sum exceedance value calculated as integral position above depth threshold below stress. vegetative modeling framework advances our ability predict propagation human-induced climatic land use or cover changes through system ecosystem. hydroecologic functioning provides an example extent cascading watershed, hillslope, riparian zones within channels reflected distribution vegetation.