# Water-Use Characteristics and Physiological Response of Moso Bamboo to Flash Droughs
## 2 Materials and Methods
### Meteorological and ET Measurements  
A 38 m tall flux tower was built in the center of the study area in 2010. An eddy covariance system was mounted on the tower at a height of 38 m and used to obtain 3 years of continuous measurements from 2012-2014. The eddy covariance system included a three-dimensional sonic anemometer (CSAT3; Campbell Scientific Inc., Logan, UT, USA) to measure wind velocities and an open-path infrared gas analyzer (Li-7500; LI-COR Biosciences, Inc., Lincoln, NE, USA) to measure the densities of CO\({}_{2}\) and H\({}_{2}\)O. The raw data were sampled at a frequency of 10 Hz and 30 min mean values were recorded using an EC100 electronics module (Campbell Scientific Inc., Logan, UT, USA) and then transmitted to a data logger (CR1000; Campbell Scientific Inc., Logan, UT, USA). The results of carbon flux, water flux, and friction wind speed were calculated on-line over a 30 min interval. For detailed information regarding the Eddy covariance system see [PERSON] et al. [(6)].  
Micrometeorological instruments, wind speed anemometers (010C, MetOne Instruments, Grant Pass, OR, USA), and air temperature and humidity instruments (HMP45C, Vaisala, Helsinki, Finland) were mounted 1, 7, 11, 17, 23, 30, and 38 m above ground. The air temperature (Ta) and the relative humidity (RH) at 17 m was used to calculate the vapor pressure deficit (VPD). A net radiation sensor (CNR4, Kipp & Zonen, Delft, the Netherlands) was mounted at 38 m above the ground. Infrared temperature radiometers (SI-111, Apogee Inc., Logan, UT, USA) were installed at 1.5 and 5 m above the ground to record surface and canopy temperatures, respectively. Precipitation measurements were obtained from a meteorological station 150 m from the study site. Soil volumetric water content (SWC, m\({}^{3}\cdot\)m\({}^{-3}\)) was monitored at 5, 50, and 100 cm depths using three CS-109 probes (Campbell Scientific Inc., Logan, UT, USA) and three CS-616 probes (Campbell Scientific Inc, Logan, UT, USA). Sensible heat fluxes were measured with HFP-01 flux plates (Hukseflux, Delft, the Netherlands) buried 3 and 5 cm below the ground. Latent heat flux was calculated based on the difference between the measured water vapor flux and the storage change of water vapor flux in the canopy-air space using the EC system. All 30 min data were recorded with a CR1000 data logger (Campbell Scientific Inc., Logan, UT, USA)  
Leaf area index (LAI, m\({}^{2}\cdot\)m\({}^{-2}\)), i.e., the MODIS 8 day 1 km LAI product (MOD15A2) was obtained from NASA's website (Atmosphere Archive and Distribution System Distributed Active Archive Center, LAADS DAA, [[https://ladsweb.nascom.nasa.gov/data/](https://ladsweb.nascom.nasa.gov/data/)]([https://ladsweb.nascom.nasa.gov/data/](https://ladsweb.nascom.nasa.gov/data/))) with an online subset output of a \(1\times 1\) km  
Figure 1: Location of the study site in Anji County, Zhejiang Province, China.  
pixel subset centered on the flux site. The LAI time-series of the flux site was extracted using ENVI5.1 software (Exelis Visual Information Solutions, Inc., Herndon, VA, USA). Annual daily leaf area index was estimated by the linear interpolation method.