People and the Biosphere

• There are two key beliefs regarding food supply and the population growth. They are Boserupian views and Malthusian views.
• Boserupian views believed that as the population grows, humans would invent new ways of producing new food. This was the more optimistic belief.
• Malthusian beliefs believed that the population would increase quicker than the food supply, causing humans to run out of food. To counteract this, there would be a crisis, such as war, famine or disease, that would decrease the population. This was the more pessimistic belief.
• Commercial activity is activity which is done to make a profit. This includes selling goods, services, food or materials.
• Fires in the Taiga are beneficial because Aspen and Birch trees sprout from burnt stumps, black spruce, jackpine and lodgepole pine cones open when burned, releasing seeds. However, disadvantages of Taiga fires are that fire tolerant species will begin to dominate reducing biodiversity, the forest will not regenerate properly as trees will not mature between fires and trees that cannot tolerate fire decline causing the animals that feed on them to decline too.
• Direct threats to the biosphere caused by people include logging for softwood and pulp and paper production. Canada and Russia account for over 40% of all deforestation between 2000 - 2013. Cutting down trees also results in loss of habitat and increases carbon in the atmosphere. 400 million tonnes of paper is produced per year, more demand for paper, causes more trees to be cut down.
• Indirect threats to the biosphere caused by people include hydroelectric power potential and fossil fuel exploitation. 11,000 kilometres of Taiga forest were flooded during the James Bay hydroelectric power project in Canada. Tar sands in Alabasca are a major part of fossil fuel exploitation, 500 km ^2 has been mined so far, the Taiga is deforested to create more space for mining.