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. 
[Source: TTphoto /Shutterstock]
Identify the dominant plant phylum in the boreal forest.
coniferophyta/conifer/coniferous/gymnosperms/pinophyta ✔
In some areas there are gaps in the boreal forest where trees fail to grow and peat tends to accumulate. Suggest reasons for this.
a. waterlogged soils/poor drainage OR acidic soil OR anaerobic conditions/soil ✔ b. organic matter not «fully» decomposed «leading to peat formation» OR decomposers/saprotrophs less active/fewer in cold «temperatures» ✔
An increase in global temperatures poses a critical threat to boreal forests. Explain the consequences of climate change to this northern ecosystem.
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/change their distribution due to warmer conditions ✔
Suggest one advantage for the evergreen trees of the boreal forest being pollinated by wind.
Discuss the advantages of the production of seeds enclosed in fruit.
The boreal forests are situated close to the north pole and even in summer the intensity of sunlight is lower than at the equator. Sketch a graph showing the effect of light on the rate of photosynthesis, labelling the axes.
a. -axis labelled as light intensity/amount of light AND -axis labelled as rate of photosynthesis/rate of oxygen release/rate of carbon dioxide uptake ✔ b. curve starting at/slightly to the right of the -axis origin and rising rapidly and then more slowly and plateauing but never dropping ✔
In some boreal species, Rubisco is down-regulated during the winter months. Describe the role of Rubisco in photosynthesis.
