- By Lucie Belly, Léa Bissiere, Estelle Bouvier
Problematic: Why protect peatlands?
LucieDOC 1 : Peatlands climate change
Words: Peatlands - Carbon store - Greenhouse emissions - Wetlands - Photosynthesis - Drainage - Peatlands restoration - Ecosystems
PEATLANDS : A peatlands, by definition, is a wetland, colonized by vegetation, whose particular ecological conditions have led to the formation of a soil consisting of a peat deposit.
CARBON STORE : when they are not degraded peatlands accumulate carbon that is found then stored long term in peat. At the planetary scale, then they occupy about 3% of the land, the peatlands store the equivalent of ¾ of the carbon in the atmosphere. Peatlands are considered to be the most more efficient in terms of carbon storage.
GREENHOUSE EMISSIONS : Greenhouse emissions are gaseous components that absorb the infrared radiation emitted by the earth's surface and thus contribute to the greenhouse effect. The increase in their concentration in the Earth's atmosphere is one of the factors causing global warming. Peatland restoration can therefore bring significant emissions reductions.
WETLANDS : wetlands are land, whether logged or uncultivated, usually flooded or gorged with fresh, salt or brackish water permanently or temporarily; vegetation, when it exists, is dominated by hygrophilous plants for at least part of the year
PHOTOSYNTHESIS : Process of organic matter production by plants under the action of light, thanks to chlorophyll.
DRAINAGE : Of various origins (development, urbanization, agriculture), drainage has strongly influenced the state of the peat bogs. It causes the drying up of these environments, resulting in the swarming and trivialization of the flora and fauna, or the total disappearance of the peatland.
PEATLANDS RESTORATION : Re-watering is one of the key points of peatland restoration. The systematic closure of drain networks allows, in many cases, re-humidification of the surrounding soil. Sphagnum development is usually very fast. When ligneous and competing species such as molinie are removed, sites may have significant self regenerating capacity. In very degraded sites, after the stripping of important surfaces by stripping, it is necessary to initiate the recolonization by the reimplantation of some pioneer species.
ECOSYSTEMS : An ecosystem is a dynamic set of living organisms (plants, animals and micro-organisms) that interact with each other and with the environment (soil, climate, water, light) in which they live.
Selected words (2)= Peatlands - Carbon store
Peatlands video1572343651.mp4 (1.6MB)
Carbon store video1572343665.mp4 (0.8MB)
Selected words (3): Ecosystems - Greenhouse emissions - Drainage : VID_20191117_113218.mp4 (3.1MB)
LéaVidéo 1: Peatland and peoples
-BIODIVERSITY: Diversity of living species in a given space and time. Peatlands are home to many rare and protected species.
-MIGRATORY BIRD: A migratory bird is a bird that travels, depending on the season, from a breeding area to a wintering area, where it spends the winter. Unlike sedentary species, migratory birds need to change their habitat in order to feed. The peat bogs and more generally the wetlands are the pleasure of the migratory birds since they constitute a refuge of choice for the avifaune. Today, half of the threatened migratory bird species depend on wetlands.
-PEAT DEGRADATIONS: Peatlands, like most wetlands, were once considered putrid, unhealthy, disturbing and dangerous swamps, with stinking miasma and populous and evil creatures. Until recently, they have been victims of prolonged reclamation operations and have almost disappeared. However, in the face of current challenges related to water resources and the significant biological diversity that this environment presents; it seems interesting to wonder about the real state of peatlands on a global scale.
-SLOWING THE WATER: Peatlands have the ability to regulate floods because they store excess water.
-Organique muséum: The peat that forms the soil of peat bogs has the particularity of preserving organic elements such as seeds over a long period. Some seeds trapped inside the peaty soil dates from the last glacial area.
-ORGANIC MUSEUM: Peat, which is the soil of peat bogs, has been collected and preserved in the peat for thousands of years. Archaeological remains, human artefacts, ancient bodies and pollen grains allow archaeologists and palynologists to reconstruct lifestyles and landscapes. dating back almost 14,000 years, some seeds trapped inside the peaty soil dates from the last glacial area.
-PEAT: Fossilized plant debris due to slow and incomplete decomposition of the material within an acid and asphyxiating soil. It must be said that a peat bog is a dystrophy, result of a disturbance of an ecosystem for exemple a Lake. Inside a peat bog, the microbial decomposition activity is absent because the medium is acid with a Ph between 3 and 4 and asphyxiating. Result: When plant biomass production is greater than its base decomposition, there is accumulation of organic matter and therefore peat formation.
-SPHAGNUM MOSSES: Sphagnum is a plant species that is found only in peat bogs, it is part of the group of bryophytes and has different peculiarities: It is able to absorb and contain three times its own weight in water and it has the property of to acidify its biotope so that it best meets its ecological requirements. The acidification of one and the formation of a peat bog is therefore caused by the development and death of sphagnum that create a layer phenomenon.
-SPONGE: A support designed to absorb liquids and discharge them under mechanical pressure, Sphagnum, which is a plant species subservient to peat bogs, naturally fulfills the function of sponge within the peat ecosystem.
Selected words (2)= Peat - Sphagnum mosses
Peat video1572811208.mp4 (0.5MB)
Sphagnum mosses video1572811223.mp4 (0.4MB)
Selected words (3)= Organic Museum - Biodiversity - Migratory Birds video1573393923.mp4 (1.7MB)
EstelleVidéo 2: Peat formation
Words: Old landform - Sediments -Bogs plants - Sphagnum mosses - Blanket bog -Plant seed (seed bank )- Cottongrass - Waterlogged.
OLD LANDFORM: A landform is a feature on the Earth's surface. There are four major types of landform: plains, plateaus, hills and mountains. The old landform is at the origin of the formation of peat, when the glaciers have melted, leaving some areas covered with a layer of fresh and fertile sediments.
SEDIMENTS: Sediments are deposits of matter (set of particles) accumulated over time, due to different agents such as water, wind, ice. They then form successive layers.
BOGS PLANTS: Bogs plants are plants that grows in a soft, moist soil. Sphagnum, rush, sedge and other plants are found.
SPHAGNUM MOSSES: It is a moss of the family Sphagnaceae, found only in peat bogs. They have the ability to acidify their environment and can store large amounts of water. They play an important role in nature.
BLANKET BOG: Blanket bog is a peat bog area that forms in cool areas with high rainfall or moisture conditions. Under these conditions, peat can develop over large areas of land.
PLANT SEED: The seeds of the plants were carried by the wind and under good conditions they started to grow in the sediment. Peatlands are seed banks because they store the different seeds brought by the elements and therefore have a high genetic diversity.
COTTONGRASS: The cottongrass according to the definition is a various species of plants from the sedge family, genus Eriophorum. It is a sedge with tufted spikes that generally grows in moist areas such as peat bogs, and produces clumps of long hairs that promote seed dispersal.
WATERLOGGED: Waterlogged, acidic and nutrient-poor Are the conditions of the environment in which sphagnum mosses grows and where it is perfectly adapted to live. The species that thrives in this medium are stubborn and do not break down easily, resulting in an accumulation of their remains and peat formation.
Selected words (2)=Old landform - Waterlogged
Old landform Old_Landform.mp4 (0.9MB)
Waterlogged Watterlogged.mp4 (0.9MB)
Selected words (3)= Sediments - Bogs plants - Cottongrass video1573839338.mp4 (1.8MB)