| Date | November 2016 | Marks available | 2 | Reference code | 16N.3.SL.TZ0.13 |
| Level | Standard level | Paper | Paper 3 | Time zone | TZ0 |
| Command term | Evaluate | Question number | 13 | Adapted from | N/A |
Question
The number of plants in two fields of approximately the same size was counted.
Compare and contrast the richness and the evenness of the two fields.
A calculation of Simpson’s reciprocal index was undertaken on each field with the following results.
Evaluate these results.
A calculation of Simpson’s reciprocal index was undertaken on each field with the following results.
Evaluate these results.
Markscheme
a. same richness as they have the same number of species/total of individuals
b. field 1 has more evenness as more even distribution of numbers among the species. Allow vice versa.
a. the higher the number the more diverse/biodiverse is the field
OR
b. field 1 shows greater diversity/biodiversity (as it has a higher value)
a. the higher the number the more diverse/biodiverse is the field
OR
\(D = \frac{{N(N - 1)}}{{\sum n(n - 1)}}\)
b. field 1 shows greater diversity/biodiversity (as it has a higher value)
