Peat is one of the many materials we put on our vegetable and flower gardens to enrich the soil and help it retain moisture. It is a natural soil conditioner; it can also be dried, cut and used as fuel. In Ireland and Scotland peat is still used in rural areas as the main form of heating fuel.
Peat comprises biogenic deposits incompletely decayed, the remains of a variety of plants and sometimes trees that have accumulated in waterlogged areas over the past hundreds or thousands of years.
Peat develops in areas where there is continuous growth of vegetation that is allowed to die and accumulate in thick beds. Moderate to high levels of rainfall are mandatory and the level of free oxygen must be very low to prevent the growth of bacteria that would break down the vegetation. Poor drainage also helps saturate the mineral soil surface.
Our present peat beds developed upon the retreat of the last great ice sheet ten to fifteen thousand years ago. When the ice retreated, huge amounts of water were left lying in every depression of the landscape. Although slow to develop, this situation resulted in large amounts of peat being laid down in bogs and fens. Deposits are a minimum of 45 centimetres (1.5 feet) deep but mostly two to twelve metres (seven to fourteen feet) deep.
Peat, because of restrictions on decomposition (cool, damp summers), forms at a greater rate than it breaks down. Only part of the pine needles, leaves, stems and roots decompose; with time they are slowly transformed into peat.
The Hudson Bay Lowlands form one of the largest peat producing areas in the world. Growth is extremely slow because of the cold wet conditions in summer. A tamarack cut near Moosonee on James Bay was three metres (nine feet) high and 6.5 centimetres (2.5 inches) in diameter but under the microscope it was shown to be 127 years old. A similar tree found near Hudson Bay was determined to be at least 450 years old.
Much of these modern peat beds are made up of mosses, primarily sphagnum moss, and plants that are able to survive in acidic, nutrient-poor soils. Sphagnum moss is very well adapted to poor growing conditions and forms a thick mat that is collected and sold as peat moss. The mat sometimes floats on the water and is dangerous to walk on because there are places where a person can fall through (experience talking).
There is an extremely delicate balance between growth and decay in peat bogs. Any disturbance, such as heating of the atmosphere, will upset the balance and cause the beds to be completely destroyed. The mess of rotting vegetation that would remain after such a catastrophe would not support any form of life.
In contrast, the ancient peat beds from 300 million years ago were much different from these relatively new plots. The great shallow seas and swamps that covered much of the tropical and subtropical regions in ancient times were thick with giant club mosses, horsetails and ferns. Eventually, these partially decaying plants created gigantic beds of peat, that under pressure and high temperatures, slowly turned from peat into fossil fuels, coal, oil and gas.
Photo by Clayton Rollins.
Peat comprises biogenic deposits incompletely decayed, the remains of a variety of plants and sometimes trees that have accumulated in waterlogged areas over the past hundreds or thousands of years.
Peat develops in areas where there is continuous growth of vegetation that is allowed to die and accumulate in thick beds. Moderate to high levels of rainfall are mandatory and the level of free oxygen must be very low to prevent the growth of bacteria that would break down the vegetation. Poor drainage also helps saturate the mineral soil surface.
Our present peat beds developed upon the retreat of the last great ice sheet ten to fifteen thousand years ago. When the ice retreated, huge amounts of water were left lying in every depression of the landscape. Although slow to develop, this situation resulted in large amounts of peat being laid down in bogs and fens. Deposits are a minimum of 45 centimetres (1.5 feet) deep but mostly two to twelve metres (seven to fourteen feet) deep.
Peat, because of restrictions on decomposition (cool, damp summers), forms at a greater rate than it breaks down. Only part of the pine needles, leaves, stems and roots decompose; with time they are slowly transformed into peat.
The Hudson Bay Lowlands form one of the largest peat producing areas in the world. Growth is extremely slow because of the cold wet conditions in summer. A tamarack cut near Moosonee on James Bay was three metres (nine feet) high and 6.5 centimetres (2.5 inches) in diameter but under the microscope it was shown to be 127 years old. A similar tree found near Hudson Bay was determined to be at least 450 years old.
Much of these modern peat beds are made up of mosses, primarily sphagnum moss, and plants that are able to survive in acidic, nutrient-poor soils. Sphagnum moss is very well adapted to poor growing conditions and forms a thick mat that is collected and sold as peat moss. The mat sometimes floats on the water and is dangerous to walk on because there are places where a person can fall through (experience talking).
There is an extremely delicate balance between growth and decay in peat bogs. Any disturbance, such as heating of the atmosphere, will upset the balance and cause the beds to be completely destroyed. The mess of rotting vegetation that would remain after such a catastrophe would not support any form of life.
In contrast, the ancient peat beds from 300 million years ago were much different from these relatively new plots. The great shallow seas and swamps that covered much of the tropical and subtropical regions in ancient times were thick with giant club mosses, horsetails and ferns. Eventually, these partially decaying plants created gigantic beds of peat, that under pressure and high temperatures, slowly turned from peat into fossil fuels, coal, oil and gas.
Photo by Clayton Rollins.
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