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Endangered species   [ Conservation status - Ecology ]
Endangerment

Dictionary of botanic terminology
index of names

     
  A general term that refers to a species facing imminent extirpation or extinction.  
     
An endangered species is a species whose population is so reduced that it is facing a very high risk of extinction in the wild throughout all or a significant part of its range, due to habitat change, reduction or destruction, over-collection or excessive capture, disease or predation, lack of regulation or management, or other natural or man-made factors.
Many countries have laws offering special protection to these species (forbidding hunting, banning their habitats from development, etc.) to prevent extinction. Only a few of the many truly endangered species actually make it to the lists and obtain legal protection. Many more species become extinct, or potentially will become extinct, without gaining public notice.

The conservation status of a species is an indicator of the likelihood of that endangered species continuing to survive.

See: Threatened Species
     

 


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Holdfast roots  [ Botany  ]

Dictionary of botanic terminology - index of names

 
     
  Some species of climbing plants develop holdfast roots which help to support the vines on trees, walls, and rocks. By forcing their way into minute pores and crevices, they hold the plant firmly in place.  
     
Climbing plants, like the poison ivy (Toxicodendron radicans), Boston ivy (Parthenocissus tricuspidata), and trumpet creeper (Campsis radicans),  develop holdfast roots which help to support the vines on trees, walls, and rocks. By forcing their way into minute pores and crevices, they hold the plant firmly in place. Usually the Holdfast roots die at the end of the first season, but in some species they are perennial. In the tropics some of the large climbing plants have hold-fast roots by which they attach themselves, and long, cord-like roots that extend downward through the air and may lengthen and branch for several years until they strike the soil and become absorbent roots.

Major references and further lectures:
1) E. N. Transeau “General Botany” Discovery Publishing House, 1994
     

 

 

 

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