Seed dispersal

The seed dispersal in plants is the process of passive transport of seeds for the purpose of propagating the plants.

It is true, the process spread - the vegetation dynamics - the result of the process, the distribution of species - as it examines the Geobotany - to distinguish.

Plants use a number of different propagation mechanisms of their seeds. These are generally divided into six major groups:

  • The Zoochorie, spread by animals
  • The Anemochorie that dispersal by wind
  • The Semachorie that dispersal by wind and animal dispersal
  • The Hydrochorie, spread by water
  • The Hemerochorie, spread by humans
  • The Autochorie, the self- propagation.

Each of these forms is again divided more finely.

Zoochorie

The Zoochorie, spread by animals recognizes the following fine structure:

  • Epichorie that spread through attachment Velcro Hafter
  • Adhäsionshafter
  • Klebhafter
  • Synzoochorie, hiding the propagation
  • Processing spread
  • Spread during the nest building

Some authors also include the Tierballisten and Anthropochorie to the Zoochorie.

In the animal propagation are usually mammals and birds, but insects, the spreader. A special form of Zoochorie is the Anthropochorie - the spread by humans.

You either take the seeds with food on and later divorced him again ( Endochorie ) or deposit it as food provision in hiding ( squirrels hide nuts and many of them are unable to retrieve, see hiding propagation ) or have the seed specific Anhaftungsmechanismen with which they adhere to the fur or feathers of animals ( eg burdock or sticky substances like the oak mistletoe, see Epichorie ).

Expires seed dispersal via the mechanism of food intake, the semen must be protected in the digestive tract of animals by a solid, durable shell or other structures from destruction during the comminution of food ( chewing ) and the digestion of food. How effective can this mechanism of propagation, show the " tomato forests ", which can grow up with sewage sludge on fields after fertilization.

Anemochorie

Anemochorie, the wind spread is the most original form of the propagation of plants. It was already used by the first land plants of the earth. This shape is further divided into

  • Meteorochorie, the propagation by Airman
  • Chamaechorie, propagation through floor roller

When Anemochorie the plant air movement serves to spread their seeds. This can even be done by the plant in strong wind " shaken " is, releasing their seeds or in part, that the seeds have complex flight mechanisms that they can carry away over long distances from the parent plant.

Arguably, the most famous small " parachutes " - they are formed from the calyx ( pappus ) at the seed maturation - the dandelions and similar composite flowers.

The fruits of various species of maple ( Aceraceae ) are well known for their striking propeller-like flight in the fall. Similarly, the seeds in ash trees (Fraxinus ) and elm (Ulmus ); there are winged, single-seeded nut fruits, which are called " Samara ".

Example of spring tail flyer seeds (Clematis )

A maple seed

Semachorie

The Semachorie is divided into fine animal dispersion and wind scattering. The difference Anemochorie is that diasporas can not fly. Movements of the plant by wind or animal movements provide only that capsules, pods, follicles are so unbalanced that they spread like a castor seeds.

Hydrochorie

When the water spreading the seeds often have floatation devices in the form of air sacs. There are also species that when it rains (eg rocking motion on impact of raindrops ) release their seeds first, and hope for a washing away the seeds.

An impressive example of the flow of water is the seed of the coconut palm. The outer pericarp of the coconut is the propagation time of fibrous and filled with air, so that all the seed is buoyant. Despite its designation as a nut is at the coconut is not a nut in the botanical sense, but rather a drupe.

The Hydrochorie is divided into fine

  • Nautochorie, the floating diffusion
  • Bythisochorie, spread by the flow of rivers
  • Ombrochorie, spread by raindrops with the fine division into Regenschwemmlinge
  • Regenballisten

Hemerochorie

The Hemerochorie is now one of the most important propagation forms with which plants to completely conquer new habitats. This includes the

  • Ethelochorie, propagation by seed
  • Speirochorie, the spread as seed companion
  • Agochorie that spread through unintentional transport

Self- propagation ( Autochorie )

The mechanisms that are available to plants for self- propagation available are summarized below Autochorie.

  • Ballochorie the spread by spin mechanism, which is further divided into fine Juice pressure spreader
  • Dehydration spreader

The self- propagation mechanisms ranging from the spherical shape ( Kullereffekt ) to complex shapes such as skidding (eg Geranium Family ) or creep ( eg filaree family) of the seed. Mechanisms that rely solely on gravity (see Kullereffekt ) are called barochore mechanisms. The seeds are usually heavy and roundish. With these devices, some species bridge several meters.

  • Plant morphology
  • Plant propagation
Biological dispersal Seed dispersal#Wind Pappus (flower structure) Hippocastanoideae Papaver
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