Elevated CO_2 and total biomass of woody plants
Meta-analysis on effects of elevated CO_2 on total biomass of woody plants
This dataset has been used as an example in Hedges et al. (1999) to describe methods for the meta-analysis of response ratios. The complete dataset with 102 observations and 26 variables is available online as a supplement. Here only a subset of 10 variables is provided and used in the examples.
A data frame with the following columns:
| obsno | observation number |
| papno | database paper number |
| treat | treatment code |
| level | treatment level |
| n.elev | number of observations in experimental group (elevated CO_2-level) |
| mean.elev | estimated mean in experimental group |
| sd.elev | standard deviation in experimental group |
| n.amb | number of observations in control group (ambient CO_2-level) |
| mean.amb | estimated mean in control group |
| sd.amb | standard deviation in control group |
Hedges LV, Gurevitch J, Curtis PS (1999): The meta-analysis of response ratios in experimental ecology. Ecology, 80, 1150–6
data(woodyplants)
# Meta-analysis of response ratios (Hedges et al., 1999)
#
m1 <- metacont(n.elev, mean.elev, sd.elev,
n.amb, mean.amb, sd.amb,
data = woodyplants, sm = "ROM",
studlab = paste(obsno, papno, sep = " / "))
summary(m1, prediction = TRUE)
# Meta-analysis for plants grown with low soil fertility treatment
#
m2 <- update(m1, subset = (treat == "fert" & level == "low"))
summary(m2, prediction = TRUE)
# Meta-analysis for plants grown under low light conditions
#
m3 <- update(m1, subset = (treat == "light" & level == "low"))
summary(m3, prediction = TRUE)Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.