1 / 35

Investigating habitats

Investigating habitats. What is a habitat?. A place where an organism lives A habitat will have certain characteristic physical conditions eg: Desert –less than 250 mm of rainfall per year-arid-sparse vegetation

moe
Télécharger la présentation

Investigating habitats

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Investigating habitats

  2. What is a habitat? • A place where an organism lives • A habitat will have certain characteristic physical conditions eg: • Desert –less than 250 mm of rainfall per year-arid-sparse vegetation • Seashore –area of land which has regular submersion in sea water or splashing by sea water

  3. Habitats around the school • Pond (Mopo)

  4. Beech Wood Habitat

  5. Measuring Physical Conditions • In the pond we can measure: • Depth in different places • Temperature in shallow and deep water • pH of water • Light levels around the pond

  6. Measuring physical conditions • In the wood we can measure: • Light levels • pH of soil • Moisture level in soil • Depth of soil

  7. Physical conditions • These may vary with season-seasonalchanges eg temperature, length of day and light levels • These may vary at different times of the day- diurnal changes

  8. Seasonal Changes • In the Uk there are seasonal changes in temperature, light levels, day length and rainfall. • Organisms show adaptations to cope with these changes

  9. Adaptations to seasonal change • Deciduous trees-lose leaves in the autumn. • Trees can be damaged by snow and wind if they have a large number of leaves

  10. Deciduous trees cont.. • Water may be frozen in the ground during the winter and so it may be difficult to replace water lost by transpiration through leaves • Photosynthesis during the winter is much reduced (dull days/short day length/cool). However, the leaves are likely to use more food than they make.

  11. Seasonal adaptation in animals • Migration in birds- swallows fly south in winter returning in summer to breed when there is plenty of food (insects)

  12. Seasonal Adaptation in Animals • Hibernation- small mammals lay down fat in the autumn and then find a sheltered burrow/nest in which to sleep for a few months. • During this inactive period their breathing and heart rate are lowered to eke out their stores of fat • They wake up in spring when food is easier to find and the weather is not so extreme

  13. Hibernation in hedgehogs and doormice

  14. Diurnal changes in organisms • Flower opening- eg celandine (woodland plant) • Flowers shut at night to prevent other animals from taking pollen (food) without achieving pollination • Flowers open in the day when insects which do carry out pollination are active

  15. Diurnal changes in animals • Bats- feed at night and sleep in the day • Although they have poor eyesight bats are adapted to flying and feeding at night by a highly developed hearing which is based on echo locationThey emit a high pitched squeak and avoid obstacles by detecting the echo Large ears -funnel echo Into ear

  16. Techniques used to find out which organisms live in a habitat. • 1. Quadrat- a frame, often 0.5mx 0.5m wide, are place in various places and the organisms found within it are recorded quadrat

  17. Identification of species in quadrat

  18. Techniques used to find out which organisms live in a habitat. • 2. Pit fall trap Method for collecting surface living animals

  19. Techniques used to find out which organisms live in a habitat. • 3. pooter

  20. Techniques used to find out which organisms live in a habitat • 4. sweep net Sweep net-for catching airborne insects

  21. Techniques used to find out which organisms live in a habitat • 5. branch shaking Lay sheet on ground-shake branches-collect Dislodged animals

  22. Techniques used to find out which organisms live in a habitat • 7. pond net

  23. Use evidence to find out which species live in a habitat Owl pellet-indigestible bones and fur are regurgitated

  24. Animal tracks

  25. Animal Dung Rabbit droppings

  26. Evidence of badgers in a habitat

  27. Badger Sett

  28. Badger Dung

  29. After collecting data about the community in the habitat then.. • We can estimate the population of an organisim in the habitat. Count the number of individual plants in the quadrat

  30. Cont… • 1 Place quadrat in different locations within the area of study ( chosen randomly) • 2 Calculate the average number of plants per quadrat • 3 Measure the area of the sample area (length x width) • 4 Multiply the average number of plants per quadrat by the number of times that the quadrat fits in to the total area ie: • pop = av. No per quad x (total area/quadrat area)

  31. Uneven distribution of a plant species This plant is not scattered but is found in a large clump

  32. How can we show this uneven distribution-carry out a transect Transect line

  33. Transect shows uneven distribution A transect shows uneven distribution

  34. Record species found at intervals along the transect line This transect clearly shows a distribution pattern-species are recorded at stations across the line (every other metre here)

  35. Transect across a bike track A distribution pattern exits here- Recording soil moisture, pH, light levels etc at each station may give evidence as to why

More Related