# Elevated CO_2 and total biomass of woody plants

### Description

Meta-analysis on effects of elevated CO_2 on total biomass of woody plants

### Usage

1 |

### Format

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

### Details

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.

### Source

Website http://www.esapubs.org/archive/ecol/E080/008/

### References

Hedges LV, Gurevitch J, Curtis PS (1999),
The meta-analysis of response ratios in experimental ecology.
*Ecology*,
**80**, 1150–6.

### Examples

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 | ```
data(woodyplants)
# Meta-analysis of response ratios (Hedges et al., 1999)
#
meta8 <- metacont(n.elev, mean.elev, sd.elev,
n.amb, mean.amb, sd.amb,
data=woodyplants, sm="ROM",
studlab=paste(obsno, papno, sep = " / "))
summary(meta8, prediction=TRUE)
# Meta-analysis for plants grown with low soil fertility treatment
#
meta9 <- update(meta8, subset=(treat=="fert"&level=="low"))
summary(meta9, prediction=TRUE)
# Meta-analysis for plants grown under low light conditions
#
meta10 <- update(meta8, subset=(treat=="light"&level=="low"))
summary(meta10, prediction=TRUE)
``` |