Deforestation increase the level of carbon dioxide in the atmosphere because when trees are burned carbon dioxide is released, carbon dioxide is also, released when trees are decomposed by microorganisms. Cutting down trees also, reduces the amount of carbon dioxides taken up by the photosynthesis and trapped in the wood and carbon dioxide is
greenhouse gas therefore, Trees play a huge role in the carbon cycle. They convert the CO2 in the air to oxygen, through the process of photosynthesis. Show
Deforestation and the Carbon CycleChanges in forest cover over time. Examine the image of changes in forest cover, pictured on the right. In the past, much of the Earth was once covered by forests. However, the majority of these forests were cleared long ago to make way for the needs of a growing human population. This is particularly true in regions with a temperate climate such as Britain and other parts of Europe where agriculture took an early hold. Interestingly, the World Wide Forest Report found that when the Roman Empire was in control of Europe, 90% of the continent was forested land. Today, as indicated in the image on the right, Western Europe has now lost over 99% of its primary forest. Forests influence climateForests and Climate Forests play an integral role in Earth's climate. Tropical, temperate and boreal forests each have varying impacts on the climate by both cooling and warming the Earth. The relationship between forests, climate, and the carbon cycle is currently an area that scientists are intensively studying.
Causes and stages of deforestationStages of deforestation If left to themselves, forests impacted by natural events such as wildfires, will regenerate over time. Forests can also be restored by reforestationreestablishing/planting forest on land that had recent tree cover. and afforestation refers to land that has been without forest for a very long time. projects. Deforestation is different. When land is deforested, trees are not replaced and the land is converted to a non-forest use. For this reason, deforestation has long term effects on the carbon cycle, climate and the environment.
Stop and Think1: Describe how deforestation can impact the the amount of carbon dioxide in the atmosphere. Trouble in the Amazon?Biomass carbon stored in tropical rainforests. NASA When we think about the Amazon Rainforest being cut down, we might immediately think of a tragic loss of biodiversity. However, as indicated in the NASA image on the right, there are massive amounts of carbon stored in the biomass of the Amazon Rainforest.
DiscussIn terms of the carbon cycle, explain why deforestation in the Amazon is a global concern and not just a regional concern for the Brazilians. Mini-Case Study: Using Sustainable Farming to Stop a Vicious Feedback Cycle of Slash and Burn Farming in Honduras.
Slash and Burn Farming Cutting down trees is only one part of the complex "carbon cycle" story in areas of deforestation. What happens to the land left behind? Answers to this question are often dependent on the local economy and the needs of small communities to provide for their families. In many parts of the world, small farmers and ranchers use a very old technique called "slash and burn" to clear and prepare the land for agriculture and cattle. In slash-and-burn agriculture, farmers will typically cut forests months ahead of the dry season. During the dry season, the "slashed" trees dry out and are then burned. The ash from the burned trees fertilizes the soil to support crops such as as rice, corn and soybeans and grass for cattle. Unfortunately, soil nutrients such as nitrogen are used up fairly quickly, the land becomes barren and farmers then move on to slash-and-burn other parts of the rainforest. In this way, fire and soil become part of this complex carbon cycle, the economy of the rainforest and the people who live there. So, what can be done to mitigate the impact of slash and burn farming on the carbon cycle? Read about the work of Mike Hand, a British ecologist, and Inga trees to find out! Maize grown in an Inga crop alley Mike Hand, a British ecologist, has lived in and studied the rainforests in Honduras for over twenty years. He observed that slash and burn was creating a vicious feedback cycle that destroyed forests in order to create agricultural land that could be farmed only temporarily. Eventually, the cleared land turned into a nutrient-deficient, barren wasteland; farmers grew poorer and poorer, and then farmers cut down more rainforest. Mike's ideas and efforts on stopping this vicious feedback cycle of "slash and burn" were portrayed in an award-winning documentary Up in Smoke. Activity:
DiscussIn what ways does deforestation impact local people and their economies? Stop and Think2: Think about the complex story of slash and burn agriculture and the carbon cycle in the Central American and Amazon rainforests. Describe how slash and burn agriculture impacts the amount of carbon dioxide in the atmosphere. HINT: You may want to incorporate what you learned about wildfires, black carbon and feedbacks in Lab 2C into your answer. Optional ExtensionsResearch the latest research! New research on the carbon cycle, climate and the environment is on-going. You can use ScienceDaily and Phys.org to research recent research on deforestation by using combinations of the following tags: deforestation, afforestation, reforestation, carbon, carbon cycle. As you discover and read more recent research, how does this research inform what you have learned so far about the carbon cycle in this module? Here are two examples: Deforestation is Messing with our Weather and War, Plague no Match for Driving Up CO2 Readings on deforestation, reforestation, and afforestation:
Why deforestation increases the amount of carbon dioxide in the atmosphere?Forests and trees store carbon . When they are degraded or completely cleared, e.g. by fire – a process referred to as deforestation – this stored carbon has the potential to be released back into the atmosphere as carbon dioxide and contribute to climate change .
What are 2 reasons deforestation contributes to global warming?All told, deforestation causes a triple-whammy of global warming: We lose a crucial ally in keeping excess carbon out of the atmosphere (and in slowing global warming), Even more emissions are created when felled trees release the carbon they'd been storing, and rot or burn on the forest floor, and.
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