Canadian Forest Service Publications
The effects of drainage on substrate water content at several forested Alberta peatlands. 1996. Rothwell, R.L.; Silins, U.; Hillman, G.R. Canadian Journal of Forest Research 26(1): 53-62.
Available from: Northern Forestry Centre
Catalog ID: 18931
Hydrologic drainage criteria that describe the position of the water table between adjacent ditches are commonly used to assess the initial effectiveness of peatland drainage projects for tree growth improvement. However, these criteria do not reflect the soil conditions that regulate tree growth and performance after drainage. The effect of three drainage ditch spacings (30, 40, and 50 m) on the spatial variability of soil water conditions at three drained boreal Alberta peatlands was studied. Soil water content (0–30 cm depth) was found to be insensitive (p = 0.686) to drainage ditch spacing several years after drainage. Greater variation was observed between different sampling locations (p = 0.024) relative to the position of the ditch edge within similar ditch spacings. Spatial distribution of soil water in the unsaturated zone was found to be inversely related to the degree of water table lowering. Spatial patterns of soil water content were strongly associated with changes to substrate bulk density resulting from post-drainage peatland subsidence.