BBC News | SCI/TECH | Soil loss threatens food prospects. By environment correspondent Alex Kirby Scientists say impoverishment of the soil is a major threat to the Earth's ability to feed itself. They have found that nearly 40% of the world's agricultural land is seriously degraded. The damage has already had "a significant impact" on the productivity of about 16% of the planet's farmland. And its economic and social effects have been much more significant in developing countries than in rich ones. The scientists, from the International Food Policy Research Institute (IFPRI), analysed the world's agro-ecosystem using data from satellites, maps and tabular data sets.
Multiple causes Working with colleagues from the World Resources Institute (WRI), they formed part of a larger international initiative, the Millennium Ecosystem Assessment. They say the seriously degraded areas include 75% of central America's cropland, 20% of Africa's, and 11% of Asia's. Erosion, two-thirds of it caused by water and the rest by wind. Remedies possible. Land degradation causes $10 billion loss to South Asia annually. Land degradation causes $10 billion loss to South Asia annually The environmental impact on the countries of the South by soil erosion and other forms of land degradation is all too familiar.
A recent United Nations study shows the high economic cost of such land degradations to the South Asian countries. By Maritin Khor SOIL is one of the most vital of our natural resources. Indeed, there is a thesis, quite difficult to refute, that the rise and fall of civilisations in history can be linked to the quality and management of their soil and land.
For from the soil comes food and other crops and plants that provide medicine, clothing and so many other things we need for daily life. And the retention of soil in its natural state and habitat prevents erosion, river silting and flooding. When land is disturbed or degraded, the ecology is damaged. Environmentalists are familiar with the above cause-and-effect scenario. But soil degradation and erosion is also an economic issue. Gross underestimate. Soil. An important factor influencing the productivity of our planet's various ecosystems is the nature of their soils. Soils are vital for the existence of many forms of life that have evolved on our planet. For example, soils provide vascular plants with a medium for growth and supply these organisms with most of their nutritional requirements.
Further, the nutrient status of ecosystem's soils not only limit both plant growth, but also the productivity of consumer type organisms further down the food chain. Figure 1: Most soils contain four basic components: mineral particles, water, air, and organic matter. Organic matter can be further sub-divided into humus, roots, and living organisms. Soil itself is very complex. Organic Activity A mass of mineral particles alone do not constitute a true soil. Humus is the biochemical substance that makes the upper layers of the soil become dark. It enhances a soil's ability to hold and store moisture. Translocation Soil Texture Soil pH Soil Color. NRCS Soils. International Biochar Initiative | International Biochar Initiative. Web Soil Survey - Home.