New study forecasts over 25 percent depletion of world's forests

Forests worldwide will continue to slowly shrink before leveling out at a lower level, say researchers based at the University of Guelph, Ontario, Canada, in a new study.

Varied trends, mostly downwards in terms of forest cover, affect the world’s forest from illegal logging in Indonesia, associated with palm oil production, causing horrendous smog hundreds of miles away in Singapore to natural phenomena like ash-dieback disease, currently affecting many established hardwoods in Western Europe.

The Guelph University researchers analyzed forests trends around the world, developing a mathematical model showing future land use changes. Their findings make dispiriting reading for those arguing that forest cover needs to be maintained as part of a strategy to lockdown carbon that would otherwise find its way into Earth’s atmosphere as the greenhouse gas carbon dioxide.

The researchers’ most likely scenario shows Earth’s forests will decline from covering 30 percent of Earth's land area today to 22 percent within 200 years. The loss of forest cover forecast is almost 27 percent.

The scientists’ modeling looked at a number of different scenarios, taking in opposing factors such as global forest regeneration countering deforestation and reforestation cut short by renewed losses.

The research, entitled, "Outlook on a worldwide forest transition" published in the Oct. 9, 2013, issue of PLOS One, was written by Chris Pagnutti, an NSERC postdoctoral researcher in the School of Environmental Sciences (SES) and Department of Mathematics [Unlink] and professors Chris Bauch, Mathematics and Statistics, and Madhur Anand, SES and University Research Chair in Sustainability Science.

Their analysis spanned several centuries' worth of forestry data extracted from the United Nations’ Food and Agriculture Organization as well as other sources.

One of the surprising points to emerge from the research is that, contrary to popular belief, in industrialized nations, forest cover has held steady and, in some cases, forests have even gained ground.

It’s a different story in the developing world, however. As populations expand in developing countries and the demand for agriculture increases, forests are in decline. Over the past quarter of a century, the figures are staggering. Since 1990, Earth’s forests have decreased in extent by more than 70 million hectares, an area larger than France.

In analyzing the trade-off between forest cover and agricultural land use, the researchers used the world food equation — an equation that relates agricultural land area to population, per capita consumption and farm yield. Their model took into account factors such as how improved farming methods, producing higher yields, had a knock-on effect of reducing the amount of land which would otherwise be needed to feed a growing population.

Humanity and the human population with its consequent demand for food, is the principal driver of deforestation. Just how much it’s in the driving seat can be seen by taking a look back in time at how Earth’s population has expanded.

Homo sapiens (us) is reckoned to have evolved on Earth around 160,000 years ago. It took humans that length of time for Earth’s population to reach 1 billion in 1818. Over a century passed before humanity expanded to number 2 billion in 1927.

Less than a century ago, the world must have seemed empty compared to today for, according to the Worldometer World Population Clock, today humans on Earth number almost 7.2 billion. On current trends, the world’s population will reach the milestone of 10 billion less than 40 years from now in 2062.

Knowing how much space humans need to exist — living space, agricultural, industry — the Guelph researchers calculated the impact that 10 billion figure has on forestation. The conclusion is that come that 10-billion landmark, it won't be a case of not being able to see the wood for the trees, more a case of where is the tree?

When humanity has expanded to 10 billion souls, human uses will account for two-thirds of the land area. On present day figures, and not allowing for future desertification of the Earth’s land mass, 15 percent of the land worldwide is already classed as arid. That means a mere 22 percent would remain for forest and wild pasture conservation.

Commenting on the report, co-author Madhur Anand said, “We tried to keep this model simple so there aren't too many unknown parameters. We realize that no one can determine the future, and there could be drastic changes in agricultural yield, food technologies or diet which could impact on our findings, but we attempted to explore those kinds of changes in our scenarios," and Anand continued, “Based on this model, we are most likely going to see forest cover decline around the world. Countries need to realize that this is a global issue, and if forests are to be preserved, and even grow, co-operation through intergovernmental organizations will have to continue to happen. Industrial countries could, for example, disseminate technologies to developing countries, reducing the amount of land needed for agriculture. Otherwise, we will see forests get smaller and smaller."

When it comes to the world’s forests, the message of the report that we’re all in this together could not be clearer. It should serve as a wake-up call to developed nations that pricing developing economies out of the market when it comes to food technology and even things as basic as seeds for crops, will, in the end, prove self-defeating.

Editors note: You might be interested in reading here as well: Industrial Farming Slows Climate Change?