Land

The soil we walk upon is the substance of human productivity and yet each year, an estimated 5 to 7 million hectares of agricultural lands are lost to erosion and an additional 1.5 million hectares are lost because of water logging, salinisation or alkalisation. In recent decades, poor land and water management practices have resulted in the degradation of 1.2 billion hectares of land – an area the size of China and India combined, that represents 11% of the Earth’s vegetated surface. Another 16 to 20 million hectares of tropical forests and woodlands are also lost each year. During the years 1945-1998, nearly 15% of the Earth’s vegetated soils became degraded to the point that their original biotic functions are now damaged and reclamation may be costly or impossible. In Central America alone, just under one quarter of vegetated land is moderately to extremely degraded.

Soil degradation reduces the capacity of the soil to support human life. Soil becomes degraded through wind and water erosion as well as chemical and physical deterioration. The main causes of soil degradation include overgrazing, agricultural activities, deforestation and land conversion, over-exploitation for fuel-wood, and industrialisation. All of these processes accompany human population growth and migration. Overgrazing is the most prevalent cause of soil degradation, affecting nearly 40% of all degraded land. In Africa and Australia, overgrazing has led to 49% and 80% respectively of soil degradation, mainly in semi-arid and arid regions.

Land loss and degradation threaten the livelihood and future food security of millions of people, with implications for water resources and the conservation of biodiversity. The International community has recognised the need for an integrated approach to land use management involving stakeholders at the local as well as national levels including women, small-scale food producers, indigenous people, and community level NGOs.

Soil restoration is a costly and time-consuming undertaking. Local initiatives as well as governmental soil conservation policies and programs can go a long way to prevent soil degradation from occurring and to rebuild damaged soil structure and fertility. The case of the Machakos District in Kenya illustrates how people can work together to improve a degraded area despite population growth. In the 1930s the Machakos District was considered an environmental disaster; famine relief and food imports were needed between 1942 and 1962. Over the sixty years between 1930 and 1990, the population of the district increased more than five-fold but in recent years environmental conditions have improved dramatically. Since then, soil erosion has declined because local modes of production switched from livestock grazing to small scale agriculture. The people of Machakos district created terraces to protect arable land and planted and protected trees to avoid a fuelwood crisis. Agricultural production per person and per hectare increased with the introduction of new technologies and farming systems.

The success in turning badlands to farmlands in Kenya’s Machakos District came about in large part as a result of the initiative of local inhabitants and support from governmental and non-governmental organisations. Social organisation in the form of co-operation, agricultural extension and research, funding, and administration permitted diverse groups to work together for their own benefit and for the benefit of the environment.

Source: Adapted from: Environment for People: Building Bridges for Sustainable Development, UNEP, New York, 1997, pp. 4-9.