Scientists estimate that some 5.5 million hectares of tropical forests (about twice the size of the nation of Belize) is lost each year due human agriculture. Though worrisome to environmentalists, it is important to note there is also significant agricultural land that it reclaimed by nature when it is abandoned for commercial use.
The question is, can the soil on this abandoned farmland return to its natural state relatively quickly?
Fortunately, new research reveals the answer is “Yes”. As reported in the Washington Post, a recent study found that “soil on previously deforested land can recover its fertility in less than a decade,” and do so largely without any help from mankind.
As printed in the Washington Post:
“The study, published Thursday in the journal Science, found that under low-intensity use, soil on previously deforested land can recover its fertility in less than a decade. Characteristics such as the layering of plants and trees in a forest, as well as species diversity, came back in about 25 to 60 years.
‘I was totally surprised how quickly it went,’ said Lourens Poorter, an ecologist at Wageningen University in the Netherlands and lead author on the paper. ‘These forests can recover very fast and they can do it by themselves.’
… Poorter says [this recovery] is due to a number of factors. The subsurface soil, for example, often remains relatively vibrant after deforestation, which enables a faster recovery. The warmth and humidity of the tropics also allow trees to grow extremely fast, with some species climbing more than a dozen feet per year.
And this all happens largely without human intervention, Poorter said. Seeds, roots and stumps embedded in the soil, or the spread of plants from adjacent forests, kick-start the recovery process.
‘The influence of humans is relatively minor compared to what nature itself is doing,’ he said. ‘The conditions are that there has to be nearby forests, and the soil can’t be too degraded.’
Although these trends had been previously observed on the local level or in a small number of locations, this paper drew on 77 sites in three continents, comprising 2,275 plots and 226,343 stems.