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African Rainforests Continue to Face Challenges
The African continent contains about 30 percent of the world’s global rainforests, second only to the Amazon. Scientists and conservationists met at Oxford1 University to discuss changes the forests are expected to undergo in the 21st Century.
Africa’s tropical forests face challenges from deforestation, hunting, logging and mining, as well as climate change.
“Climate change is a major issue for much of the world, but for Africa, in particular. And there’s much interest and concern around Africa’s forests, which is the second largest area of tropical forest in the world after the Amazon forest. And yet there’s been very little synthesis of the research that’s there. There’s much less known about both climate and forest and people and there interaction in Africa compared to many other regions of the world,” said Yadvinder Malhi is a professor of ecosystems2 science at Oxford University and director of Oxford’s Center for Tropical Forests.
He said the conference brought together experts in climate change, ecology, social sciences, economics, anthropology3 and archeology to discuss Africa’s rainforests.
“They’re important at an international level for many reasons. They hold a large amount of carbon. They seem to be absorbing carbon from the atmosphere, which is slightly slowing down the rate of climate change. In the case of Africa, the recycling of water. So water that falls in the Congo region gets taken up in the roots of trees and evaporated back into the atmosphere where it forms clouds and new rain,” he said.
The clouds that form over the Congo Basin actually have long range effects on water supplies and weather patterns in parts of Asia and even North America.
West and Central Africa
There’s a big difference between the forests of the Congo Basin and West Africa. Malhi says there’s been extensive deforestation in West Africa. Much of the land has been cleared for agriculture over the last 20 to 30 years.
“When we look at the Congo Basin we see a very different situation. That’s an area that is at the moment almost all intact forest and has had relatively4 low rates of deforestation. And the reasons why those rates have been low are varied5 from country to country. But in the largest area, the Democratic Republic, it’s been political instability and poor infrastructure6 linked to that instability that has meant that this large forest reserve has not currently really faced very heavy pressure, at least compared to forests of Asia or the Amazon,” Malhi said.
However, he said that could change with new investment and infrastructure and expansion of industrial scale plantations7.
About 3,000 years ago, the Congo forests were affected8 by natural climate drying. Forests retreated and were replaced by grasslands9.
“At the same time, around two and a half thousand years ago, Iron Age humans settled in much of the forest, cleared it with axes, with iron axes. And then they had a population collapse10 around a thousand years ago and the forest regrew. And this is quite a different history from the history we see in the Amazon rainforest, where there’s been pretty continuous forest over human history and earlier. And also where there was human impact it was not with iron instruments. There was no Iron Age in the Amazon,” he said.
The combination of natural climate drying and the wide scale felling of trees resulted in fewer species of trees compared to other tropical forests. However, that’s not necessarily a bad thing.
“The species that are left seem to be relatively resilient to a large extent. They can recolonize disturbed areas quite quickly. They can spread quite quickly, regrow quite quickly. So if one area gets deforested, you can still find the species elsewhere,” he said.
Food Security
Modern day deforestation is often done to make room for agriculture. The U.N. says by 2050 the world population is expected to rise to nine billion. That means a much greater demand for food. But the Oxford professor says there are ways of meeting that demand that do not require widespread deforestation. One of them is making current agricultural land much more productive.
“Much of agriculture in Africa is of very low productivity. Very low inputs11 of fertilizers and nutrients12. You could have the current agricultural output of the Africa tropical forest region in 40 percent of its current agricultural land, leaving 60 percent of the land available for forests if the agriculture was intensified13. So, it’s not a simple tradeoff between more food means more land and therefore less forests,” he said.
Malhi says once all the information from the conference is analyzed14, recommendations will be made to governments, U.N. agencies and others. They’re expected to include proposals for protecting remaining rainforests, better land management for agriculture and new research into the effects of climate change.
The conference ran from January 4-6.
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1
Oxford
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| n.牛津（英国城市） | |
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ecosystems
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| n.生态系统( ecosystem的名词复数 ) | |
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anthropology
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| n.人类学 | |
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relatively
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| adv.比较...地，相对地 | |
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varied
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| adj.多样的，多变化的 | |
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infrastructure
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| n.下部构造，下部组织，基础结构，基础设施 | |
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plantations
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| n.种植园，大农场( plantation的名词复数 ) | |
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affected
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| adj.不自然的，假装的 | |
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grasslands
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| n.草原，牧场( grassland的名词复数 ) | |
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collapse
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| vi.累倒；昏倒；倒塌；塌陷 | |
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inputs
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| n.输入( input的名词复数 )；投入；输入端；输入的数据v.把…输入电脑( input的第三人称单数 ) | |
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nutrients
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| n.（食品或化学品）营养物，营养品( nutrient的名词复数 ) | |
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intensified
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| v.（使）增强， （使）加剧( intensify的过去式和过去分词 ) | |
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analyzed
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| v.分析( analyze的过去式和过去分词 )；分解；解释；对…进行心理分析 | |
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