Data from: A synthesis of ecosystem aboveground productivity and its process variables under simulated drought stress

1. Projected increases in drought duration and intensity under climate
change considerably affect aboveground productivity (ANPP) and associated
process variables (photosynthesis rates (Pn), stomatal conductance (gs),
soil respiration (Rs), and soil water content (SWC)). 2. Although ANPP has
been extensively studied across the ecosystems, there is little consensus
on how the spatiotemporal patterns of ANPP will be altered with increasing
drought stress. Here, we present a global meta-analysis of ANPP and the
four variables (610 observations from 78 studies) for drought duration,
intensity, and their combination. 3. Forest-ANPP had stronger negative
responses to long-term drought (34.44%; ≥ 4 yrs) than short-term drought
(10.78%; ≤ 1 yr), and decreased more in Mediterranean forests than in
tropical forests. Decreases in Pn and gs were strongest under long-term
moderate drought. In the short term, Rs increased by 5.66% under light
drought, but decreased by 14.12% and 28.43% under moderate and severe
droughts. Grass-ANPP showed a nonlinear decrease with extended duration,
and the rate slowed. Within light to severe intensities, ANPP decreased
linearly, but became stable under extreme condition. In the short term,
ANPP reduced more seriously with increasing drought intensity
(12.01-30.34%). With aggravation of drought stress, the reductions in Rs
and SWC increased. There was significant heterogeneity in grassland
responses to drought stress. The greatest decreases in ANPP, Pn, and gs
were observed in North America, and the reductions in Rs and SWC were
greater in Western Europe. Shrub-ANPP showed stronger negative responses
to long-term moderate drought (12.59%). Pn and gs declined significantly
with increasing drought intensity. Variations in Rs to drought duration,
intensity, and their combination were more complex, either showing
positive or negative responses (dominated). 4. Synthesis. Forest-ANPP
shows high sensitivity to long-term moderate drought, whereas grass-ANPP
is more responsive to short-term drought. Compared to forests and
grasslands, shrub-ANPP exhibits less sensitivity to droughts. Different
responses of ecosystems were predominantly driven by physiological
mechanisms or species differences in turnover time, community
architecture, and drought adaptation strategies. Given these findings,
future studies should focus on nonlinear patterns, response thresholds,
and adaptation mechanisms when predicting and modelling feedback between
ecosystems and climate change.