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Biodiversity

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Question 18

An ecologist sampled communities of ground beetles in two woodlands, Site P and Site Q, using pitfall traps. The table below shows the abundance of each species recorded:

SpeciesSite PSite Q
Carabus violaceus2410
Pterostichus madidus39
Nebria brevicollis26
Abax parallelepipedus15

Using the formula for the index of diversity:

d=N(N−1)∑n(n−1) d = \frac{N(N-1)}{\sum n(n-1)} d=∑n(n−1)N(N−1)​

which of the following shows the correct index of diversity (ddd) for each site and the correct ecological conclusion?

dSite P≈1.55d_{\text{Site P}} \approx 1.55dSite P​≈1.55 and dSite Q≈4.10d_{\text{Site Q}} \approx 4.10dSite Q​≈4.10; Site Q is more stable because it has a higher species evenness.

dSite P≈0.64d_{\text{Site P}} \approx 0.64dSite P​≈0.64 and dSite Q≈0.24d_{\text{Site Q}} \approx 0.24dSite Q​≈0.24; Site P is more stable because it has a higher index value.

dSite P≈1.55d_{\text{Site P}} \approx 1.55dSite P​≈1.55 and dSite Q≈4.10d_{\text{Site Q}} \approx 4.10dSite Q​≈4.10; Site P is more stable because the dominance of Carabus violaceus reduces competition.

dSite P≈1.53d_{\text{Site P}} \approx 1.53dSite P​≈1.53 and dSite Q≈3.72d_{\text{Site Q}} \approx 3.72dSite Q​≈3.72; Site Q is more stable because it has a higher index value.

Biodiversity Questions

  1. A Level
  2. /Biology
  3. /Biodiversity