Data from: Shock and stabilisation following long-term drought in tropical forest from 15 years of litterfall dynamics

Litterfall dynamics in tropical forests are a good indicator of overall
tropical forest function, indicative of carbon invested in both
photosynthesising tissues and reproductive organs such as flowers and
fruits. These dynamics are sensitive to changes in climate, such as
drought, but little is known about the long-term responses of tropical
forest litterfall dynamics to extended drought stress. We present a
15-year dataset of litterfall (leaf, flower and fruit, and twigs) from the
world's only long-running drought experiment in tropical forest. This
dataset comprises one of the longest published litterfall time series in
natural forest, which allows the long-term effects of drought on forest
reproduction and canopy investment to be explored. Over the first 4 years
of the experiment, the experimental soil moisture deficit created only a
small decline in total litterfall and leaf fall (12% and 13%,
respectively), but a very strong initial decline in reproductive
litterfall (flowers and fruits) of 54%. This loss of flowering and
fruiting was accompanied by a de-coupling of all litterfall patterns from
seasonal climate variables. However, following >10 years of the
experimental drought, flower and fruiting re-stabilised at levels greater
than in the control plot, despite high tree mortality in the drought plot.
Litterfall relationships with atmospheric drivers were re-established
alongside a strong new apparent trade-off between litterfall and tree
growth. Synthesis. We demonstrate that this tropical forest went through
an initial shock response during the first 4 years of intense drought,
where reproductive effort was arrested and seasonal litterfall patterns
were lost. However, following >10 years of experimental drought,
this system appears to be re-stabilising at a new functional state where
reproduction is substantially elevated on a per tree basis; and there is a
new strong trade-off between investment in canopy production and wood
production.