Question 18N.2.SL.TZ0.c
| Date | November 2018 | Marks available | [Maximum mark: 2] | Reference code | 18N.2.SL.TZ0.c |
| Level | SL | Paper | 2 | Time zone | TZ0 |
| Command term | Explain | Question number | c | Adapted from | N/A |
Boreal forests stretch across Canada, Russia and Scandinavia. This northern ecosystem accounts for 29 % of the world’s forest areas. The long, cold winters favour tall evergreen trees with either needles or scale-like leaves. These trees are wind-pollinated and their seeds are not enclosed in a fruit. The photograph shows a typical boreal forest in winter.
An increase in global temperatures poses a critical threat to boreal forests. Explain the consequences of climate change to this northern ecosystem.
[2]
a. higher temperatures so more transpiration/droughts/dehydration/water shortage ✔
b. more forest fires ✔
c. more/new pests/diseases because of the changed conditions ✔
d. competition from trees/plants «that colonize/spread to boreal forests» ✔
e. trees/«named» organisms «of boreal forests» not adapted to warmer conditions
OR
trees/«named» organisms migrate/extend range due to the warmer conditions ✔
f. trees die so there is loss of habitat for animals ✔
g. faster decomposition/nutrient cycling «so conditions in the ecosystem change» ✔
h. standing water/floods due to more snow/permafrost melting ✔
