Land, they say, is life. The earth beneath our feet transforms death into life, as the organic matter of decomposing plants, manure and animals is broken down by billions of micro-organisms. Mix this with particles of rock and minerals, as well as oxygen, nitrogen and carbon, and you have the rich but fragile ingredients of our planet’s skin, basic to human survival. For soil is not just the feeder of plants and thus of animals: it is the substratum of civilization.

Cultivating the land through agriculture has allowed humanity vastly to increase its population, and so to undertake great works of water and soil management. Today the world’s most productive land, which once supported a profusion of wildlife, is under human control.

But we have eroded our planet’s thin skin of soil at alarming rates, without understanding the need to replenish it. Clearing forests for land exposes soil to corrosive rainfall, and the poor, eroded earth that is left pushes cultivators ever further into the forests. Salination, deforestation, soil erosion and other abuses have led to famine, war and population crash. Chemical-based pesticides and fertilizers which in the 1960s increased food production are failing as pests develop resistance and toxic residues pollute soil, water, food and wildlife. In addition, chemical fertilizers require huge amounts of fossil fuels to manufacture and, used over the long term, deplete the quality of the soil.

Along with logging and agriculture, mining and oil/gas extraction are the largest assaults on the land. In the past 150 years we have drastically rearranged our landscapes, drilling and quarrying, beheading mountains and displacing communities. The results have been toxic sludge, dead rivers and silted waterways, floods and landslides.

Who controls the land – and whether it is exploited as a resource or stewarded for future generations, is a fundamental moral and political struggle.

New Internationalist

Desertification in Langtou Gou, China Langtou Gou, a village 130 kilometres from Beijing, is being gradually smothered by sand from the Gobi Desert. Recent sandstorms swept dune-loads into once-fertile lands. Each year, over 100 million people suffer the impact of desertification and another 2,500 square kilometres of land turn to desert. Overcultivation and overgrazing are the main causes. With little vegetation remaining in parts of northern and western China, the strong winds of late winter and early spring can remove millions of tons of topsoil in a single day - soil that can take centuries to replace. Photo: Mark Henley / Panos

Wheat farm, Great Plains, Montana, US Monoculture on massive mechanized farms has contributed to major soil erosion in the US. In the 20th century the US lost an amount of topsoil that took about 1,000 years to form. Photo: Alex A Maclean / Still Pictures

Boy by Shell billboard, Gabon Around Shell's terminal in Gabon is an important nature reserve, supposedly protected by its national park status. Most people here work for Shell, but the oil reserves are running out. When they do, people may be forced to turn to logging and hunting within the reserve. In 2000, fossil fuels like oil accounted for 77 per cent of world energy consumption. The environmental costs of conventional energy production and use include air, soil and water pollution, as well as acid rain and loss of biodiversity. Photo: Sven Torfinn / Panos

Nickel smelter, Norilsk, Russia This plant spews molten slag; Russia is the world's largest nickel producer. Mining leaves an indelible mark on landscapes and, as one of the most dangerous occupations, on people's lives. Instead of increased mining, we could reuse or make more use of minerals already obtained. Photo: Gerd Ludwig / Panos

Rice terraces, Guangxi Province, China Rice terraces are found in the mountainous parts of southern China. The Dragon's Backbone Terraces were built from the Yuan Dynasty to the beginning of the Qing Dynasty. So they have been around for hundreds of years - an early example of human management of the landscape. Photo: Xintian Pan / UNEP / Still Pictures

EARTH – THE FACTS
• The most significant change in the structure of ecosystems has been the transformation of approximately a quarter (24%) of Earth’s terrestrial surface cultivated systems. More land has been converted to cropland since 1945 than in the 18th and 19th centuries combined.¹

• Farming may be the human endeavour most dependent upon a stable climate. Plant scientists from Asia have found that rising temperatures may reduce grain yields in the tropics by as much as 30% over the next 50 years.²

• More than half of all the synthetic nitrogen fertilizer ever used has been used since 1985. Human activities have now roughly doubled the rate of creation of reactive nitrogen on the land surfaces of the Earth and tripled the flow of phosphorus (also from fertilizer) into the oceans.¹

• Africa is the only continent where food production per capita declined after 1960. This was due largely to soil erosion.³