11.8 Methods of maintaining biodiversity

Question 1

Maintaining biodiversity

Answer 1

• Conservation is the name given to the preservation and careful management of the environment and of natural resources
• Two main categories of conservation:
  1) in situ conservation - within the natural habitat
  2) ex situ conservation - out of the natural habitat
• Classification of species:
  1) extinct - no organisms of the species exist anywhere in the world
  2) extinct in the wild - organisms of the species only exist in captivity
  3) endangered - a species that is in danger of extinction
  4) vulnerable - a species that is considered likely to become endangered in the near future
• Scientists also promote the practice of sustainable development: economic development that meets the needs of people today, without limiting the ability of future generations to meet their needs

Question 2

In situ conservation

Answer 2

• Maintains genetic diversity of species and evolutionary adaptations that enable species to adapt continually to changing environmental conditions.

Question 3

In situ conservation: Wildlife reserves

Answer 3

• Controlled grazing: only allowing livestock to graze a particular area of land for a certain period of time to allow species to recover, or keeping a controlled number of animals in a habitat to maintain it
• Restricting human access: not allowing people to be in the area avoiding potential damage
• Controlling poaching: includes creating defences to prevent access, issuing fines, or more drastic steps such as the removal of rhino horns
• Feeding animals: ensures more organisms survive to reproductive age
• Reintroduction of species: adding species to areas that have become locally extinct, or whose numbers have decreased significantly
• Culling or removal of invasive species: an invasive species is an organism that is not native to an area and has negative effects on the economy, environment, or health
• Halting succession: succession is a natural process in which early colonising species are replaced over time until a stable mature population is achieved

Question 4

In situ conservation: Marine conservation zones

Answer 4

• Less well established than terrestrial ones
• Lundy island is currently the only statutory marine reserve in England
• Marine reserves are vital in preserving species-rich areas such as coral reefs, which are being devastated by non-sustainable fishing methods

Question 5

Ex situ conservation: Botanic gardens

Answer 5

• Plant species can be grown successfully in a botanic garden: here the species are actively managed to provide them with the best resources to grow, such as the provision of soil nutrients, sufficient watering, and the removal of prevention of pests

Question 6

Ex situ conservation: seed banks

Answer 6

• A seed bank is an example of a gene bank: a store of genetic material
• Seeds are carefully stored so that new plants may be grown in the future
• They are dried and stored at temperatures of -20 degrees to maintain their viability
• Seed banks don’t work for all plants. Some seeds die when dried and frozen and sadly the seeds of most tropical rainforest trees fall into this category

Question 7

Ex situ conservation: Captive breeding programmes

Answer 7

• Produce offspring of species in a human-controlled environment
• They are often run and managed by zoos and aquatic centres
• CBP provide the animals with shelter, an abundant supply of nutritious food, an absence of predators and veterinary treatment
• Some organisms born in captivity may not be suitable for release in the wild:
  1) diseases - there may be loss of resistance to local diseases in captive-bred populations
  2) Behaviour - some behaviour is innate, but much has to be learned through copying or experience
  3) Genetic races - the genetic make-up of captive animals can become so different from the original population that the two populations cannot interbreed
  3) Habitat - in many cases the natural habitat must be restored to allow captive populations to be reintroduced.

Question 8

Conservation agreements: International union for the conservation of nature (IUCN)

Answer 8

• Intergovernmental organisations like IUCN assist in securing agreements between nations
• At least once a year the IUCN publishes the red list.
• The IUCN was also involved in the establishment of the Convention on International Trade in Endangered Species (CITES)
• This treaty regulates the international trade of wild plant and animal specimens and their products

Question 9

Conservation agreements: The Rio Convention

Answer 9

• The Convention on Biological Diversity (CBD) requires countries to develop national strategies for sustainable development
• The united nations framework convention on climate change (UNFCCC) is an agreement between nations to make steps to stabilise greenhouse gas concentrations within the atmosphere
• The united nations convention to combat desertification (UNCCD) aims to prevent the transformation of fertile land into desert and reduce the effects of drought through. programmes of international cooperation

Question 10

Conservation agreements: Countryside stewardship scheme

Answer 10

• Specific aims of the scheme:
  1) sustaining the beauty and diversity of the landscape
  2) Improving, extending and creating wildlife habitats
  3) restoring neglected land and conserving archaeological and historic features
  4) improving opportunities for countryside enjoyment
• It has now been replaced by the environmental stewardship scheme