Question 19M.3.SL.TZ2.d
| Date | May 2019 | Marks available | [Maximum mark: 1] | Reference code | 19M.3.SL.TZ2.d |
| Level | SL | Paper | 3 | Time zone | TZ2 |
| Command term | State | Question number | d | Adapted from | N/A |
A survey was made of the intertidal zone at Butter Lump Bay, Great Cumbrae, Scotland. The three species of barnacle found were Elminius modestus (EM), Chthamalus montagui (CM) and Semibalanus balanoides (SB). The kite diagram shows the vertical distribution of these three species from the low tide mark at 0 m to 2.25 m above low tide.
[Source: reprinted from Estuarine Coastal and Shelf Science, 152, M C Gallagher, et al., The invasive barnacle species,
Austrominius modestus: Its status and competition with indigenous barnacles on the Isle of Cumbrae, Scotland,
pages 134–141, 2014 with permission from Elsevier]
State one abiotic factor that could have determined the distribution of barnacles.
[1]
a. exposure/tides/waves ✔
b. temperature ✔
c. surfaces «of attachment» ✔
d. resource availability/nutrients ✔
e. pH ✔
f. light ✔
g. salinity ✔
Do not accept biotic factors eg: “competition or predation”
