Conservation of Plants and Animals - Exemplar Solutions 4
CBSE Class 8 Science
NCERT Exemplar Solutions
CHAPTER 7
Conversation of Plants and Animals
NCERT Exemplar Solutions
CHAPTER 7
Conversation of Plants and Animals
LONG ANSWER QUESTIONS
25. Is deforestation associated with global warming? Explain.
Ans. Yes. Plants absorb carbon dioxide from the atmosphere to carry out photosynthesis. Deforestation results in decreased number of trees leading to accumulation of carbon dioxide in the atmosphere.
Carbon dioxide in the atmosphere traps heat rays reflected by the earth. With more carbon dioxide in the atmosphere, more of the sun's radiation is being reflected back to earth, instead of space, and this is causing our average temperature to rise.
With constant deforestation,the ratio of greenhouse gases in the atmosphere increases. In this way, deforestation is a major issue when it comes to global warming.
26. How does deforestation lead to frequent floods and droughts?
Ans. Forests are needed to build in resilience in the natural ecosystem. They are a buffer against extreme floods and droughts. Deforestation results in decreased water holding capacity of soil.
This reduces the infiltration of water into the ground which causes floods. Due to deforestation and soil erosion, the topmost layer of the soil gets destroyed and the soil loosen. Deforestation leads to higher level of carbon dioxide in the atmosphere which causes global warming. Scarcity of trees disturbs the water cycle and may reduce rainfall leading to droughts.
27. Why should we save paper?
Ans. To prevent deforestation, save energy and water needed for manufacturing the paper. Chemicals used to manufacture the paper also cause pollution. Anything we can do to save paper will help reduce the amount of trash going into landfills, and it will also reduce energy use and pollution associated with manufacturing, transporting, and recycling new paper products.
Perhaps most importantly, when we save paper, we reduce the need to cut down trees to make new paper. Recycling of paper is good for the environment and it will save more trees. If we don't recycle and just throw it away, we have to cut down more trees to make more paper that would be unnecessary if we would just reuse the paper that we already have made.
Recyclable paper helps the environment because it stops a lot of used paper being put into waste dumps or burn, and also if one recycles paper it means manufacturers don't have to cut down more trees to make paper , hence making the process more eco-friendly.
Recyclable paper helps the environment because it stops a lot of used paper being put into waste dumps or burn, and also if one recycles paper it means manufacturers don't have to cut down more trees to make paper , hence making the process more eco-friendly.
