measuring ecosystems
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Measuring ecosystems. Experiment 1 - Surveying. You will make an accurate to scale drawing of the ecosystem we are going to study. The drawing will need to have accurate measurements (+/- 01m) to show key distances. - PowerPoint PPT PresentationTRANSCRIPT
Measuring ecosystems
Experiment 1 - Surveying
• You will make an accurate to scale drawing of the ecosystem we are going to study.
• The drawing will need to have accurate measurements (+/- 01m) to show key distances.
• You will need to record the accurate positions of the 8 key (identified by your teacher) trees.
Make a plan…..Now using your plan go and measure what you think will be needed to produce your plan.
Then using your measurements and a relevant method (electronic or by hand) make your accurate drawing.
Experiment 2 Measuring trees
For each of the 8 key trees we will measure:1. The trunk diameter,2. The average crown diameter,3. The tree height.You will need to record your data using a relevant method. Don’t forget units!
Measuring trunk diameter
• Diameter of a tree gives an indication of its age.
• C = π D or • D = C/π
D
C
Measuring tree height
• H = tree height• L = distance from
the tree you measured the angle (α) at (in meters).
• H = h1 + h2• h1 is your eye
height (in meters)• h2 = L x tan(α)
(α)
Experiment 3 – measuring canopy
The measurements for the canopy in all 4 directions North, East, South and West gives you an ability to estimate the approximate ground area the tree covers and so an ability approximate the solar energy absorbed by the tree.
NorthSouth
Tree calculations and presentation of data.
• To present your processed the data:On the initial survey you completed you need to record the tree’s ‘vital statistics’ and the canopy as a scaled ‘kite diagram’ positioned where the tree was. E.g.:
D = 0.15mH= 8.5m
N
S
EW
D = Trunk diameter at 1m from the groundH = tree height
Experiment 3.- Measuring Biodiversity SIMPSON’S DIVERSITY INDEXTo calculate Simpson's Index for a particular area, the area must first be sampled. The number of individuals of each species present in the samples must be noted. For example, the diversity of the ground flora in a woodland, might be tested by sampling random quadrats. The number of plant species within each quadrat, as well as the number of individuals of each species is noted. There is no necessity to be able to identify all the species, provided they can be distinguished from each other.
To work out SBI we will need to measure:N = total no. of all species n = no of individuals of a particular species
High value of D = diverse ecosystem /stable, low value = not diverse ecosystem / unstable
Diversity is a measure of – a) the no. of different species and b) the evenness each species
Which is the most diverse , Meadow 1 or 2? Numbers of individuals
Flower Species Meadow 1 Meadow 2
Daisy 300 20Dandelion 335 49Buttercup 365 931Total 1000 1000
Animal type Number of individuals
Goldfish 24
carp 5
Frogs 6
Water boatman
1500
Water snail 1200
Water flea 2500
Species Number (n)
n (n-1)
Woodrush 2 2
Holly 8
Bramble 1
Yorkshire fog
1
Sedge 3
Total (N)
N = N- 1 = N(N-1) = ∑ n(n-1) = D =
15
14
210
2+56+0+0+6=64
3.28
Lets do a bit of practice…..
Now work out the SBI for the pond….
Your task…….• Compare the SBI for a 2 different flowerbed or
grass areas and compare them. (one of the flower bed areas must be the one in the corner nearest administration!)
• Points to consider: 1. you have to compare the same area to make
it a fair test. 2. Do not destroy or trample any of the
beautifully cared for plants in your efforts
Experiment 4 – Soil analysis
• Soil has many of the abiotic factors that will affect plant growth from pH to nitrate and water availability. It also has a major function in nutrient cycling and is a major store for organic matter. This experiment will show you ways to measure all of this.
Bed rock
Illuvial zone
Elluvial zone
Organic zone
Using the soil test kits….
• The soil test kits allow you to test for:1. Soil pH2. Potassium (K)3. Phosphorus (P)4. Nitrate Use the ‘Soil Auger’ to get your small sample and follow instructions in the pack to measure your nutrient contents.
Measuring water, organic and mineral contents - method
• Take a 250ml beaker, weigh it, record this value.• Half fill the beaker with soil, weigh it, record
this value.• Heat the beaker over a bunsen burner for 10
minutes to dry it (stirring occasionally), leave it to cool, weigh it, record this value.
• Pour the soil onto a metal tray and spread it out. Using a bunsen burner very carefully apply the flame directly to the soil – it will glow red hot, (this will burn off the organic matter) Leave it to cool. Carefully (so as not to lose any soil) put the soil back in the beaker and reweigh it, record this value.
Record the data in a suitable format.From the data you have recorded work out:1. The original mass of the soil,2. The mass of water lost from the soil with the first heating,3. The mass of organic matter lost from the soil by the
second burning,4. The inorganic matter left behind after all else is removed.Decide on a suitable way to present this data graphically – hint - the original mass of the soil would be 100% of the soil and everything else would be a proportion of that original mass.
Measuring water, organic and mineral contents - data
Each of the 4 experiments will be assessed using the following rubric