Study of an Ecosystem: Grassland

You are required only to study any one ecosystem, and to know five animals and five plants from your ecosystem.

Plants Grasses Clover Buttercups Dandelions Daisies Nettles Poppies Thistles Dock Primrose Bluebell Animals H = herbivore, C = carnivore, O = omnivore, D = detritus feeder (detritus is dead and decomposing organisms ) Earthworms (D) Caterpillars (H) Rabbits (H)Snails (H) Ladybirds (C) Badgers (O) Slugs (H)Bees (H) Foxes (C)Spiders (C) Wasps (H, C) Hedgehogs (O) Beetles (C, H, O) Butterflies (H) Thrushes (C)Aphids (H) Moths (H)Blackbirds (O)

The study of an ecosystem involves studying a number of sample habitats, as follows: Mapping identifying plants and animals estimating the numbers of plants and animals measuring the environmental (abiotic) factors presenting the information

Collection methods DeviceProcedureCollected KnifeCutPlants, limpets TrowelDigPlants, animals in soil PooterSuckInsects Beating TrayShake bushesCrawling animals Pitfall trapSink into soil or sandCrawling animals Sweep netSweep through grassInsects Collecting plants and animals involves some of the methods shown in the table below:

DeviceProcedureCollected Tullgren FunnelHeat Soil (using a lamp) Small organisms from soil Baerman FunnelHeat soil in waterSmall organisms from mud Mammal trapsSet the trapMammals Potassium permanganate solution Pour onto soilEarthworms Cryptozoic trapPlace on groundSlugs, snails, worms, woodlice

A suitable key is used to identify and name organisms. A qualitative study records the presence or absence of species. A quantitative study records the number of each species. Quantitative studies can be: subjective (i.e. a personal judgement is made as to the number) objective (i.e. an independent method of calculating numbers is used) Subjective methods are not recommended, because they depend on individual judgements, which may vary from person to person.

Errors may arise in the study of an ecosystem in the following ways: mistakes may be made in judgement and recording conditions change in the ecosystem over time accidental discoveries may be made the habitats studied may not accurately reflect the overall ecosystem

A quantative study of plants in a habitat involves using: quadrats, which are examined for: (a) Percentage cover of plants or stationary animals. (b) Frequency transects: (a) Line transect (rope marked at intervals – record what touches the line). (b) Belt transect (equivalent to quadrats taken in a line – methods used are the same as for quadrats).

A quantitative study of animals in a habitat involves using: the capture–recapture method, i.e. Number = C 1st × C 2nd _____________ M 2nd

Three sample abiotic factors EcosystemSample factors Measured by GrasslandAir temperatureThermometer Soil pHpH meter or universal indicator Light intensityLight meter

Effects of abiotic factors EcosystemAbiotic factorInfluence GrasslandAir temperatureTemperature differences in different parts of the grassland will affect how well the plants (and animals) grow Soil pHSoil pH will favour some plants and therefore some animals Light intensityGrasses grow better at higher light intensities

Organisms show many adaptations that allow them to survive in their habitat. The results of a study can be presented in tables, lists, charts, graphs, diagrams, etc. The results of a study should include food chains, food webs, and pyramids of numbers. The work carried out in Activities 2–5 should be presented in a portfolio.