Europe PMC · 2026-03-10
Desert plants in China's Kalamaili Nature Reserve don't respond gradually to water — there's a hidden tipping point at roughly 28% soil moisture where plant productivity suddenly surges. Below that threshold, extra water barely helps; above it, soil nitrogen kicks in to boost plant height and biomass dramatically.
A nonlinear threshold exists near 28% soil water content — below it, biomass response to moisture is weak; above it, productivity increases sharply.
Soil nitrogen mediates the water-to-biomass pathway indirectly by enabling greater community-level plant height, not just by direct nutrient supply.
The value of plant height as a productivity driver decreases under extreme drought, and its interaction with soil moisture flips from synergistic in dry conditions to antagonistic in wetter conditions.