Sunday, October 11, 2009

World Forests

By Wendell Krossa

Intro: The rate of deforestation is decreasing (FAO). The rate of species loss is decreasing (UNEP). This is occurring while population and industrialization are increasing. Go figure, eh. Now why are the environmental alarmists telling us that overpopulation and industrialization are destroying nature?

Forest Facts

Total forest area on earth today is 4 billion hectares (46 million square kilometers out of 148 million total square kilometers of land on earth). This is 30.8% of the total land area on earth which is 13 billion hectares.

Interesting here is that the FAO notes that the rate of deforestation is decreasing.

This area of forest is the same as the total forest area in 1948 which was also 4.0 billion hectares. This area apparently dipped to 3.8 billion hectares in 1963, to 3.6billion hectares in 1980, and to 3.4 billion in the 1990s.

But the FAO Production Yearbooks show no significant decline of forest area from the 1960s to the 1990s (see graph of the history of forest cover in The Skeptical Environmentalist, Bjorn Lomberg, p.111). Gathering forest statistics has been notoriously difficult but the FAO provides the best rough estimates.

What these stats show is that forest cover on earth has remained fairly stable at about 30% of total land area over the past seven decades but it actually appears to be increasing now (46 million square kilometers today versus only 43 million square kilometers in the 1990s).

Note also that the world population in the 1940s was about 2.4 billion. It is 6.6 billion today. And industrialization has increased significantly with increasing population across the globe.

Several things stand out from these statistics. First, they undermine the basis of the alarmist’s argument that species are going extinct at increasing rates. This argument is based on the assumption that a certain number of species go extinct per area that is deforested. But this assumption is obviously wrong because there is no massive deforestation occurring and, correspondingly, species extinctions are not occurring anywhere near the rate that environmental alarmists claim (Paul Erhlich, for instance, states that some 70,000-130,000 species go extinct every year.)

However, the 1992 IUCN study found no species extinctions above the historical rate of 1.5 per year. Known extinctions have been about 675 over the past 400 years.

The environmental alarmists have been wrong on this issue because they ignore the research that shows species adapt well to secondary habitat (fragmented habitat) or they migrate to new areas. They also ignore the fact of reforestation and recovery of habitat (see “No convincing evidence for decline in tropical forests” by Simon Jenkins.)


Further, they ignore the fact that higher rates of CO2 in the atmosphere have led to a significant greening of the earth, with a 6.17% increase in Net Primary Production (NPP) which refers to world vegetative productivity (this particular increase was for the 1982-1999 period). This increase was especially notable in tropical trees (“Greening of the Earth- Summary”).

This increase in NPP may explain in part the decreasing rate of deforestation. It appears that with larger trees, more people on earth need to cut fewer trees to meet their needs. More efficient use of forest products also plays a role in reducing the need to cut trees.

To help understand the decreasing rate of extinctions in relation to the increase in NPP, I would point to research that shows that with increased CO2, plants survive better and species dependent on such plants therefore survive better also. As the Idso science team notes, “Higher atmospheric concentrations of CO2 make plants more heat tolerant, and less susceptible to extinction. If plants are better able to survive, then the animal species that depend directly or indirectly on these plants will also be better able to survive” (“The Specter of Species Extinction: Will Global Warming Decimate the Earth’s Biosphere?”, S.B. Idso, C.D. Idso, and K.E. Idso, quoted in The EKC literature provides empirical support for that claim.

Also helpful to understanding this situation re population, forests, and species is to note that improvements in GM crops, along with higher levels of CO2, have increased crop yields significantly (see research papers at co2science.org). This has led to higher crop yields on less land and this too has relieved pressure to cut more forests (“The historical increase in the air’s CO2 content has improved human nutrition by raising crop yields during the past 150 years on the order of 70% for wheat, 28% for cereals, 33% for fruits and melons, 62% for legumes, 67% for root and tuber crops, and 51% for vegetables” Climate Change Reconsidered, p.8). And, in fact, increasing agricultural yields have also resulted in the return of excess agricultural land back to nature (100 million acres of farmland were returned to nature in the US over the last century- see A Moment On The Earth by Greg Easterbrook).

These ongoing improvements in agriculture and increases in CO2 levels are vital to preserving natural areas. And contrary to the alarmist’s counter argument, we have not reached a plateau of diminishing returns in GM research. We are just getting started. The only plateau is that of reduced funding for GM research due to environmental opposition.

The sensible response to such information is to recognize that the human discovery of fossil fuels, and consequent emissions of CO2 (industrialization), has benefited all life. We have contributed significantly to the increase in NPP on earth (and particularly to increased crop yields) and this has ‘saved nature’- both plants and animals. Also, our advances in GM crop research have supported the trend toward using less land to grow more food. This too has helped save nature. We ought then to celebrate and support the human enterprise and industrialization, instead of wrongly demonizing it as a curse on nature.

These facts show that the human enterprise is not destroying nature.

Wendell Krossa wkrossa@shaw.ca
For more of Mr. Krossa's thoughts you may wish to log on to his site, The Human Spirit.

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