Drought decreases carbon flux but not transport speed of newly fixed carbon from leaves to sinks in a giant bamboo forest

Carbon (C) allocation among different plant tissues is crucial for maintaining the C balance in forest ecosystems, especially under changing climate conditions. The partitioning of newly assimilated C among plant tissues, interconnected ramets, and soil in forests dominated by giant clonal plants, such as moso bamboo (Phyllostachys edulis), and the influence of drought on this partitioning remains poorly understood. In August 2019, we performed in situ labeling of the entire crown of R0 (ramets that emerged in 2019) of moso bamboo with 13CO2 in plots subjected to a 5–year drought or left untreated (ambient control) in subtropical China. We then traced the 13C signatures in the leaves, twigs, and fine roots of R0, R1 (ramets that emerged in 2018 and are connected with R0), and R2 (ramets that emerged in 2017 and are connected with R1), as well as in soil organic C (SOC) and soil respiration over the course of one year post–labeling. Drought reduced leaf 13C assimilati..., Experimental design and sampling
In July 2014, three bamboo forests with similar slopes and altitudes were selected (Table S1). In each forest, two 12 m × 12 m plots were established, separated by a 10–m–wide buffer zone (Fig. S2). One plot out of them was randomly selected to be subjected to drought (i.e., throughfall exclusion), while the other served as a control (natural rainfall) (hereafter referred to as ‘drought’ and ‘control’, respectively). For the drought treatment, we set up transparent PVC waterproof boards suspended at about 1.5 m above the ground surface to exclude 70–80% of precipitation. A trench measuring 12 m in length, 40 cm in width, and 60 cm in depth (with roots concentrated in the 20–40 cm soil depth) was dug to prevent water from flowing into the drought treatment area from the surrounding soil and to restrict root access to areas outside the throughfall exclusion treatment area. PVC waterproof boards were inserted into the trench before the soil was refilled. Th..., # Drought Decreases Carbon Flux but Not Transport Speed of Newly Fixed Carbon from Leaves to Sinks in a Giant Bamboo Forest

Dataset DOI: [10.5061/dryad.5tb2rbpfh](10.5061/dryad.5tb2rbpfh)

## Description of the data and file structure

In 2019, we conducted an experiment in China using stable carbon isotopes to track their movement in young bamboo plants and among their older, interconnected neighbors. The experiment was carried out under both long-term dry conditions (a five-year drought) and normal conditions. We monitored the labeled carbon signals for a year, examining leaves, branches, roots, soil, and the carbon released from the soil.

### Files and variables

File: Data_Dryad_Drought_Decreases_Carbon_Flux_but_Not_Transport_Speed_of_Newly_Fixed_Carbon_from_Leaves_to_Sinks_in_a_Giant_Bamboo_Forest.xlsx

Description: The unit and full name of the abbreviations in the headline are:

Ramets includes: R0 (ramets that emerged in 2019); R1 (ramets that emerged in 2018 and are connected...,