Study: Humans Harmed 97% of Most Crucial Ecological Regions

Researchers surveyed human effect on ‘ecoregions’ from 1993 to 2009, and the results are startling.

Amazon rain forests
AP

Human activity that damages nature affected 97 percent of the areas of the world defined as having high ecological importance, according to a new study. The good news is that in some parts of the world there has been a slowdown in the extent of such damage, thanks to more efficient use of natural resources.

The findings of the study were published this week in the journal Nature Communication. It was conducted by a large group of scientists headed by researchers from Canada, Australia and the United States. During the course of the research, the scientists examined the changes in the extent of the “human footprint on nature” between 1993 and 2009 utilizing a number of measures, among them the extent of built-up areas, the extent of areas used for agriculture and pasturage, nighttime artificial illumination, the distribution of railroad tracks and roads, and the number of water sources in which there is boating and shipping. The researchers acknowledge they did not examine additional kinds of human activity that also change nature, among them environmental pollution and the spread of intrusive varieties of flora and fauna.

The main finding is that during the period of the study, the world’s human population grew by 23 percent and the global economy grew by 153 percent. However, the size of the human effect on nature calculated worldwide grew by only 9 percent.

According to the researchers, the main reason for the relatively moderate growth of the human effect is to be found mainly in countries with high incomes and a low level of corruption. In those countries there is now more efficient exploitation of natural resources and much has been done to preserve the environment.

Efficiency is measured in part by per capita changes in the footprint in each country. The researchers examined the possibility that those countries transferred the demand for raw materials to poor countries from which there are imports of raw materials and various products, thereby increasing the human influence on nature in other parts of the world.

However, they concluded that this process does not explain the low rate in the growth of the influence. However, they also acknowledged that they did not examine activities like energy production and mining. These activities have significant and numerous effects on the environment and many of them are aimed at providing fuel and mined resources from poor countries to rich countries.

The heaviest pressure on natural resources is in areas suitable for agricultural use. A notable example of this is the cutting down of rain forests for crops like palm oil, or cattle ranching in South America and southeast Asia. The researchers found that in extensive areas suited to agriculture, there was hardly any change in the impact of the human footprint since those had already been changed in the past by human activity. However, in areas where the extent of the land suitable for agricultural use was more limited, there was a significant increase in the human effect on nature.

The areas where the human influence was limited are mainly deserts like the Gobi in Asia and the Sahara in North Africa. Moreover, there remain extensive areas unaffected by humanity in the rain forests in the Congo River basin in Africa and in the Amazonas forests in South America. However, in the Amazonas there is also an accelerated process of fragmenting of the area by roads and the spread of settlements and agricultural activity. These are liable to expand the influence of humans to additional forest areas.

The researchers examined 772 ecoregions, or regions of great ecological importance, and found that during the period covered by the study, in 71 percent of these ecoregions there was increasing pressure from human activity.