Shwmae (hello in welsh), good to have you back for the next enthralling instalment of “Bog” Standard; your friendly information portal for all things peaty!

I thought following my rather abstract musings in the first post and generally showing off my hippy credentials a bit too much, it might be a good idea to try and pin down some basic definitions and relationships which are essential to understanding peatlands and their distribution.

Peatlands are inherently unbalanced systems! This “unbalance” is due to the rate of organic matter produced not being matched by that being respired and decomposed. This net productivity results in a surplus of organic material which accumulates into deposits called peat (Figure 1).

 

 Figure 1- Cross Section through a peat deposit

The accumulations of Peat are a product of specific climatic controls that allow for a vegetative cover to grow at a site and for it to be waterlogged; thus providing an organic input into an anaerobic environment; which therefore has a low decomposition rate.

The majority of global Peatlands are found within climatic regions characterised by high humidity and low evaporation rates (meaning there’s generally plenty of water about). A key point to make here is that not only does there need to be water, but that the water body must have a low competency (energy state) in order to provide an environment in which organic material can accumulate.

So you might say that all you really need for peat to form is a low energy, pretty wet sort of a place, or as Moore and Bellamy (1974:9) put it:

“Any surface which reduces the rate of dissipation of the energy, that reduces the competency of the water body, to a level where sediments are no longer carried by traction, can constitute a template for peat formation.”

As anyone can see, that description covers a pretty large area and therefore it’s clear that the most important variables in the form of peatland system produced, is the hydrological balance of the basin and the volume and concentration of minerals in solution (Bellamy and Moore 1974).

 A common subdivision within Peatlands is the distinction made between Minertrophic and Ombrotrophic forms based on the sources of water.

Ombrotrophic: Refers to soils and vegetation that receive all water and mineral inputs from the atmosphere.

Minertrophic: Refers to soils and vegetation that receive the majority of their water supply and minerals from surface or groundwater sources.

Differences in the sources of minerals and water lead to alternative environmental gradients which dictate floristic communities. For example the singular reliance of Ombrotrophic peatlands (Bogs) on atmospheric inputs results in closed systems within a landscape that express high acidity due to the acidic pH of rainfall and low nutrient values. These environments express a plant community predominantly dominated by sphagnum mosses which are adapted to these pressures.   

Alright then, I hope that’s “wetted” the appetite for peatlands (forgive the pun), I’ll be back again soon.

References:

Bellamy, D.J., and P.D, Moore., 1974. Peatlands. London: Paul Elek

Best regards

Matt