Classification and Biodiversity

• Measuring the distribution of plants


  1. Set quadrats in a row 1m apart

  2. This gives an idea of how plant life changes along a particular route e.g. along a seashore

  3. This is called a transect
• Transect


  A method of measuring the distribution of plants by setting quadrats in a row 1m apart along a particular route
• Measuring biodiversity of animals


  1. Capture/recapture technique

  2. Carefully collect organisms found in 1 area without trampling habitat or leaving litter

  3. Mark the organisms and return them to the same area

  4. Leave time for organisms to reintegrate into their community

  5. Return and again collect as many organisms as found, collect as those already marked and unmarked samples

  6. Use an equation to calculate the estimated population size
• Assumptions made when using capture-recapture data include no death, immigration or emigration, and marking technique does not affect chances of survival
• Biological control


  The use of one organism to control the population size of another species by eating it, often using a predator species to control a prey species that has become a pest
• Organisms involved in biological control


  • Predator
  • Prey
  • Pest
  • Native species
  • Alien species
  • Invasive species
• A lot of research is needed to make sure any alien species introduced into a habitat does not become invasive and affect the native species populations
• A lot of research is needed to prevent any species introduced having a negative effect on non-targeted species
• Major groups of living organisms


  • Animals
  • Plants
• Types of animals


  • Vertebrates - have a backbone, like birds, snakes, humans
  • Invertebrates - do not have a backbone, like insects, spiders
• Types of plants


  • Flowering - like daisy, rose, dandelion
  • Non-flowering - like mosses and ferns
• Classifying and naming organisms


  Traditionally based on morphological features, but more recently DNA analysis has been used to more accurately group organisms to show how related they are
• Levels of classification


  • Domain
  • Kingdom
  • Phylum
  • Class
  • Family
  • Genus
  • Species
• Scientific names


  Used as they are universal, avoiding confusion from language barriers or common names
• Adaptations


  • Morphological - e.g. Fennec foxes have large ears to radiate heat, Arctic foxes have small furry ears to reduce heat loss
  • Behavioural - e.g. Fennec foxes are mostly nocturnal and burrow under sand to avoid heat
• Competition


  • Interspecific - between different species
  • Intraspecific - between members of the same species
• Factors affecting population size


  • Competition
  • Predation
  • Pollution
  • Disease
• Biodiversity


  A measure of the variety of different species and the numbers of each of those species in a particular area
• Biodiversity is important as it provides food, potential medicines, industrial materials, and enhances human well-being
• Ways to conserve and protect biodiversity and endangered species


  • National parks
  • Seed/sperm banks
  • Sites of Special Scientific Interest
  • Local biodiversity action plans
  • Convention on International Trade in Endangered Species
• Measuring plant biodiversity


  1. Randomly throw a quadrat

  2. Count the different species and the number of each in each quadrat

  3. Take a mean number of each species of plants from all the quadrats collected

  4. Multiply up to estimate how many in the whole area
• Quadrat


  Usually a 1m square used to measure the biodiversity of plants in an area