Bogs are one of the most distinctive kinds of wetlands. The West Lake Bog receives most of its water from precipitation rather than from runoff, groundwater or streams. Bogs serve an important ecological function in preventing downstream flooding by absorbing precipitation.
A bog is a mire that accumulates peat, a deposit of dead plant material—often mosses, and in a majority of cases, Sphagnum moss. It is one of the four main types of wetlands. Other names for bogs include mire, quagmire and muskeg; alkaline mires are called fens. They are frequently covered in Ericaceous shrubs rooted in the Sphagnum moss and peat. The gradual accumulation of decayed plant material in a bog functions as a carbon sink.
Bogs occur where the water at the ground surface is acidic and low in nutrients. In some cases, the water is derived entirely from precipitation, in which case they are termed ombrotrophic (rain-fed). Water flowing out of bogs has a characteristic brown colour, which comes from dissolved peat tannins. In general the low fertility and cool climate results in relatively slow plant growth, but decay is even slower owing to the saturated soil. Hence peat accumulates. Large areas of landscape can be covered many meters deep in peat. Bogs have a distinctive group of plant and animal species, and are of high importance for biodiversity, particularly in landscapes that are otherwise settled and farmed.
Bogs are widely distributed in cold, temperate climes, mostly in boreal ecosystems in the northern hemisphere. The world's largest wetland is the peat bogs of the Western Siberian Lowlands in Russia, which cover more than 386,102 square miles. Large peat bogs also occur in North America, particularly the Hudson Bay Lowland and the Mackenzie River Basin They are less common in the southern hemisphere, with the largest being the Magellanic Moorland.
Types of bogs
Valley bog
These develop in gently sloping valleys or hollows. A layer of peat fills the deepest part of the valley, and a stream may run through the surface of the bog. Valley bogs may develop in relatively dry and warm climates, but because they rely on ground or surface water, they only occur on acidic substrates.
Raised bog
These develop from a lake or flat marshy area, over either non-acidic or acidic substrates. Over centuries there is a progression from open lake, to marsh, then fen (or on acidic substrates, valley bog). Eventually peat builds up to a level where the land surface is too flat for ground or surface water to reach the center of the wetland. This part therefore becomes wholly rain-fed (ombrotrophic), and the resulting acidic conditions allow the development of bog (even if the substrate is non-acidic). The bog continues to form peat, and over time a shallow dome of bog peat develops: a
Raised bog.
The dome is typically a few meters high in the center, and is often surrounded by strips of fen or other wetland vegetation at the edges or along streams, where ground water can percolate into the wetland.
Blanket bog
In cool climates with consistently high rainfall, the ground surface may remain waterlogged for much of the time, providing conditions for the development of bog vegetation. In these circumstances bog develops as a layer "blanketing" much of the land, including hilltops and slopes. Although blanket bog is more common on acidic substrates, under some conditions it may also develop on neutral or even alkaline ones, if abundant acidic rainwater predominates over the ground water. Blanket bog cannot occur in drier or warmer climates, because under those conditions hilltops and sloping ground dry out too often for peat to form – in intermediate climates blanket bog may be limited to areas which are shaded from direct sunshine.
Quaking bog
Quaking bog is a form of bog occurring in wetter parts of valley bogs and raised bogs, and sometimes around the edges of acidic lakes. The bog vegetation, mostly Sphagnum moss anchored by sedges (such as Carex lasiocarpa), forms a mat half a meter or so thick, floating over water or very wet peat. Walking on this surface causes it to move – larger movements may cause visible ripples of the surface, or they may even make trees sway. In the absence of disturbance from waves, the bog mat may eventually cover entire bays, or even entire small lakes.
Cataract bog
A cataract bog is a rare ecological community formed where a permanent stream flows over a granite outcropping. The sheeting of water keeps the edges of the rock wet without eroding the soil, but in this precarious location no tree or large shrub can maintain a root-hold. The result is a narrow, permanently wet habitat.
The West Lake Bog contains many carnivorous plants, most notably the pitcher plant (looks like a pitcher holding water). Carnivorous plants attract, capture, and kill small invertebrates, namely bugs. Look inside the plant and see the hairs on the inside edge. Notice the red veins running down the plant. The red veins and fragrance of the plant attracts insects and the hairs trap them inside the pitcher of water. The plant then breaks down the enzymes and the nutrients are absorbed through the cells of the plant. The pitcher plant is endangered and illegal to pick.
Many of the plants within the preserve are rare and/or endangered so DO NOT PICK ANY OF THEM.
Much of the area surrounding the West Lake Bog is best classified as marshland. Marshes are wetlands that contain floating or grasslike plants such as cattails. Many of the trees surrounding the bog are tamarack trees. Though the tamarack resembles other evergreens, it is actually a deciduous conifer, meaning that it sheds needles every fall in a similar way that the leaves fall off deciduous trees. During fall and winter you may see golden needles spread all over the ground.
The number of bogs in the United States has declined rapidly to be used for cropland or mined for peat. Bogs play in important role in regulating the global climate by storing large amounts of carbon in peat deposits. Bogs are unique communities that can be destroyed in a matter of days, but require thousands of years to form naturally.
**Logging requirements**
DO NOT POST ANSWERS IN YOUR LOG.
Send the following answers to me via email.
- The text "GC166CM West Lake Bog" on the first line
- What is the distance that the bog extends? (From the beginning of the bridge to the center of the observation deck) Tenths of a mile is fine.
- Look around you and observe, from the information above what kind of bog is this one?
- There is a sign on the observation deck, it’s all brown with white letters. What’s the number on it?
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