Consider what we industrialized Americans have done to our own homeland. Other industrialized countries have done no better. But despite the levels of deforestation, up to 60 percent of their territory is still covered by natural tropical forests. In fact, today, much of the pressures on their remaining rainforests comes from servicing the needs and markets for wood products in industrialized countries that have already depleted their own natural resources.
Industrial countries would not be buying rain forest hardwoods and timber had we not cut down our own trees long ago, nor would poachers in the Amazon jungle be slaughtering jaguar, ocelot, caiman, and otter if we did not provide lucrative markets for their skins in Berlin, Paris, and Tokyo.
Why should the loss of tropical forests be of any concern to us in light of our own poor management of natural resources? The loss of tropical rain forests has a profound and devastating impact on the world because rain forests are so biologically diverse, more so than other ecosystems e.
The biodiversity of the tropical rain forest is so immense that less than 1 percent of its millions of species have been studied by scientists for their active constituents and their possible uses.
When an acre of topical rain forest is lost, the impact on the number of plant and animal species lost and their possible uses is staggering. Scientists estimate that we are losing more than species of plants and animals every single day because of rain forest deforestation.
Surprisingly, scientists have a better understanding of how many stars there are in the galaxy than they have of how many species there are on Earth. Estimates vary from 2 million to million species, with a best estimate of somewhere near 10 million; only 1. Hundreds and thousands of these rain forest species are being extinguished before they have even been identified, much less catalogued and studied.
Wilson over a decade ago:. As terrible as these catastrophes would be for us, they can be repaired within a few generations. The one process ongoing in the s that will take millions of years to correct is the loss of genetic and species diversity by the destruction of natural habitats. This is the folly that our descendants are least likely to forgive us for. Several scientists have come up with more accurate estimates. Based on its size, the Amazon would account for about half of that.
That would mean the Amazon generates around 16 percent of oxygen produced on land, explains Malhi, who detailed his calculations in a recent blog post. That percentage sinks to 9 percent when taking into account the oxygen produced by phytoplankton in the ocean. Climate scientist Jonathan Foley , who directs the non-profit Project Drawdown which researches climate change solutions, arrived at a more conservative estimate of 6 percent.
The rest is probably used up by the countless microbes that live in the Amazon, which inhale oxygen to break down dead organic matter of the forest. Because of this balance between oxygen production and consumption, modern ecosystems barely budge oxygen levels in the atmosphere. Instead, the oxygen we breathe is the legacy of phytoplankton in the ocean that have over billions of years steadily accumulated oxygen that made the atmosphere breathable, explains Scott Denning , at atmospheric scientist at Colorado State University.
This oxygen could only accumulate because the plankton became trapped at the bottom of the ocean before they could rot—otherwise, their decomposition by other microbes would have used up that oxygen.
In its pristine state, it makes a significant contribution to pulling carbon dioxide out of the atmosphere. Coe likens it not to a pair of lungs, but to a giant air conditioner that cools the planet—one of our most powerful in mitigating climate change, alongside other tropical forests in central Africa and Asia—some of which are also currently burning.
The Amazon also plays an important role in stabilizing rainfall cycles in South America, and is a crucial home for indigenous peoples as well as countless animal and plant species. Join the conversation Create account. Already have an account? Which trees provide the most oxygen over the course of a year, deciduous or evergreen?
CBC Radio Loaded. Deciduous and evergreen trees can produce similar amounts of oxygen each year, as long as they also have a similar total leaf area. Social Sharing. Quirks and Quarks Which trees provide the most oxygen over the course of a year, deciduous or evergreen?
She asks: Which trees of the same age or size provide us with the most oxygen over the course of a year, deciduous or evergreen? According to the report's calculation, about kg of oxygen per year is consumed by one human, which is around seven or eight trees' worth. The recent forest fires around the world have cut down the number of trees in rainforests.
National Geographic cited a study from that said land plants are responsible for 34 percent of photosynthesis on the planet. However, Yadvinder Malhi, an ecosystem ecologist at Oxford University, calculated these figures in , after the wildfires, and said that the Amazon produces only 9 percent oxygen in the atmosphere. According to the National Ocean Service, with organisms like phytoplankton producing around 20 percent of oxygen in the biosphere, it is currently higher than all of the tropical rainforests on land combined.
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