Data from: The drivers of respiration shift from soil nutrients to water with the increase in temperature

The underlying mechanisms by which different levels of warming affect
respiration are likely to vary. Identifying the drivers of respiration
across varying levels of warming is essential for more accurately
predicting changes in carbon processes under future warming
scenarios.  This study conducted a long-term warming experiment
in an alpine meadow ecosystem to investigate diurnal respiration dynamics.
We analyzed diurnal and nocturnal ecosystem respiration changes under five
warming gradients and investigated the mechanisms behind these
changes.  Our results show that warming significantly decreased
diurnal respiration. Moreover, with increasing warming intensity, the
limiting factor for respiration transitioned from nutrient to water
scarcity. Low-level warming decreases soil respiration, mainly by reducing
soil nutrient pools. High-level warming mainly reduces soil respiration by
decreasing soil moisture. Warming significantly reduces aboveground
biomass, leading to a corresponding decrease in respiration. We also
observed that nocturnal respiration exhibited a pronounced and more
complicated response compared to daytime respiration under warming
conditions. Our results emphasize the critical roles of nutrients and
water in modulating CO2 emission flux under climate warming. Therefore,
soil resource management is crucial for enhancing carbon sequestration in
alpine grasslands.