Deforestation and habitat lossIB MYP Biology: Mind map

Exam questions on Deforestation and habitat loss

1. A research team in the Brazilian Amazon has compared satellite records of one region taken 20 years apart. The earlier records show unbroken rainforest. The recent records show large rectangular areas of bare ground, new roads and industrial-scale farms where forest once stood.
   Outline two reasons why rainforest is cleared in regions such as this.2 marks
2. Students at a school in the Kenyan highlands wanted to find out how plant cover affects soil erosion. They filled two identical trays with the same mass of soil and placed both on the same slope. One tray was left as bare soil and the other was covered with grass turf. They poured 2 dm³ of water over each tray at the same rate and collected the water that ran off. The runoff was filtered and the soil in it was dried and weighed. The bare tray lost 48 g of soil and the grass tray lost 6 g.
   Explain what the results show about the effect of plant cover on soil erosion.2 marks
3. In Sumatra, Indonesia, large areas of peat bog forest have been drained and cleared to make way for oil palm plantations. Peat forms where waterlogged ground slows the decay of dead plant material. The bogs were home to specialised species such as orangutans, which live only in these swampy forests.
   Explain why destroying peat bogs adds to climate change.3 marks