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A sustainable resource is one which is produced
                                 as rapidly as it is removed from the environment,
                                 so that it does not run out.

                                 We must aim for sustainable development.
                                 This  means  that  we  should  not  alter  our
                                 environment so much that we take things away
                                 and     harm     the    environment       for   future
                                 generations. We should still provide for the needs
                                 of an increasing population.




     Conservation Programmes                                  Captive breeding and the role of zoos

     Conservation  involves  management  of  an  area,        Many animal species are threatened by habitat
     and may include a number of strategies:                  degradation,  fragmentation  and  destruction.
         Preservation  -  keeping  some  part  of  the        The  International  Union  for  Conservation  of
         environment  unchanged.  This  might  be             Nature  (IUCN)  estimates  that  only  3%  of  the
         possible in Antarctica, but is less significant in   planet is designated as a protected reserve and
         a densely populated area like Britain than ...       that,  on  average,  one  mammal,  bird  or  reptile
         Reclamation  -  the  restoration  of  damaged        species  has  been  lost  each  year  for  the  last
         habitats  such  as  replacing  hedgerows  or         hundred  years.  Certain  groups  of  species  are
         recovering former industrial sites, and ...          particularly  at  risk  -those  with  a  restricted
         Creation  -  producing  new  habitats,  for          distribution,  those  of  high  economic  value,
         example by digging a garden pond, or planting        those at the top of food chains and those which
         a forest.                                            breed very slowly.

                                                              Zoos  are  areas  of  confinement  keeping
     A conservation plan involves several stages:             samples of species alive under varying degrees
         sampling to assess the number of organisms           of  captivity.  The  role  of  zoos  in  captive
         devising  a  management  plan  -  for  example,      breeding     is   becoming       more     and    more
         trying to increase a species' population based       important.  For  example,  the  Arabian  oryx  had
         on knowledge of its breeding requirements            been hunted to extinction in the wild but zoos in
         carrying out the plan                                London, San Diego and Phoenix have provided
         re-sampling  to  assess  the  number  of  the        animals to release in Oman and Jordan.
         `conserved'  species  once  more,  and  find  out    Education can help.
         whether the conservation plan has worked.                Local people can be taught about the tourist
                                                                  value of conserving species.
     As populations decrease in size, genetic variation           Students  can  be  taught  about  keeping
     is  reduced  and  a  species  may  become  more              complex      food    webs     and     about    the
     vulnerable to environmental change.                          management of habitats.




              Learning Module Organisms and Their Environment | Class 11                                     30
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