CSPs: LAI and PAR Gutianshan 2009

Usage Rights

This data is Private.

Dataset Abstract

Measuring light interception is important for understanding the conditions at the surface. Questions which had to be answered: How much of the light is reaching the ground and how much is hitting leaf material in the canopy? How efficient were the trees in filtering the light? This is important for having optimal photosynthetic performance.

Dataset Design

Digital hemispherical photographs (Canon EOS 350 fitted with Sigma 8 mm fisheye objective) were taken at the central points of each subplot (n=9), horizontally leveled at 1.3 m height above ground in summer 2009. Auto Exposure Bracketing (AEB) at +/- 2 stops. The photos were analyzed with the software Hemisfer from P. Schleppi et al (2005). LAI was calculated on plot level including 9 pictures. Correction is applied for slope, non-linearity and clumping. Measurement of Photosynthetically Active Radiation (PAR) above and below canopy. PAR is between 400 and 700 nm wavelength. Term used: LI = (PAR above canopy - PAR below canopy) / (PAR above canopy). LI was calculated on plot level including 9 pairs of measurements. PAR is measured as photon flux density (μ mol m-2 s-1).

Spatial Extent

Comparative study sites of the BEF-China Experiment.

Data Analysis

As plants are thought to compete for light, LAI gives a measure on how well the plot can exploit the resource light.

Paper proposal submissions

Published

2017

2016

Data columns available in the raw data part of this dataset

CSP
name of the CSP in the Nature ReserveBEF research plot nameReasearch plots of the Biodiversity - Ecosystem functioning experiment (BEF-China). There are three main sites for research plots in the BEF Experiment: Comparative Study Plots (CSP) in the Gutianshan Nature Reserve, having a size of 30x30m^2, measured on the ground.
Data group: BEF research plot name
Keywords: CSP
Values
CSP05
CSP02
CSP04
CSP01
CSP03
LAI
leaf area index (LAI)
Unit: dimensionless (m2 / m2)
Data group: Leaf Area Index (LAI)
Keywords: LAI, light
Values
1.69
1.72
1.95
1.48
1.64
LI
light interception (LI)
Unit: μ mol m-2 s-1
Data group: Photosynthetically active radiation (PAR)
Keywords: light
Values
0.755406143
0.726016542
0.679125793
0.653601658
0.779712715