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  • Fieldwork
    • Sampling
      • Random sampling
        • Representative sample around 2% of the area
        • Measuring tapes placed around the area to create a grid and numbers are randomly generated to make coordinates
        • Large no. of samples, at least 10 to minimise chance of skewed sample or anomalies
      • Systematic sampling
        • choose where to take samples to measure a pattern
        • Transect
          • Samples taken along a line to see what changes occur
          • Line Transect - organisms touching the line along the transect are recorded
            • Quickest
          • Belt transect - quadrats placed at intervals along transect and animals in quadrate are counted
            • Generates more complete data
          • Presented in kite graph showing biotic an abiotic factors
          • Both abiotic & biotic should be measured at each site for better understanding
    • Diffucluties
      • Large  number of organisms
      • Confounding variables such as weather
      • Organisms may be hard to find or identify
    • Measuring Abiotic factors
      • Measured with special digital electronic equipment which are quick, quantitive, accurate, calibrated and automatically recorded
      • In a terrestrial habitat - air temp., light intensity, wind speed & direction.
      • Each abiotic measurement should be repeated several times and averaged
        • Measured over a day or a year to account for daily and seasonal variations
      • Aim to correlate abiotic and biotic measurements at the same points to find a causal relationship
    • Measuring Biotic factors
      • Identification usising identification key
      • Quantitive measurements
        • Abundance
          • Counting number of organisms.
        • Richness
          • Number of different species in the sample
        • Diversity
          • Divide abundance by sampling area better measure in Simpson Diversity Index - richness & abundance
        • Growth
          • Comparing growth or size of similar organisms in different habitats
        • Biomass
          • Dry Mass - organisms much be heated to 80o to evaporate water but not burn organic material. Sample is weighed at intervals until changes stop
          • Productivity and pyramids come from measuring dry mass
    • Sampling Plants
      • Quadrats
        • Preliminary experiment to find best size quadrat
          • Species area graph
        • Quantitive
      • Density - individuals in each area/area of quadrat
        • Cant be used on plants hard to identify.
      • Species frequency -  No. of quadrate species were found in.
      • % cover - estimated and inaccurate due to layers of plants and easier if quadrat is sub decided. Used when plants are hard to identify
      • Point  Quadrat - % cover - species hit by needle are recorded and repeated. Hits/repeats give % cover
      • Abundance scale - Quantative - ACFOR. Can be made quantative by corresponding %.
    • Sampling Animals
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