Glossary

• Overgrazing - Too many livestock, such as goats or cows, strip the soil of its vegetation and expose it to erosion by wind and water;
  
• Deforestation - Trees hold soil together and help water the land by channeling rainwater into the soil. When they are chopped down, the soil is eroded by the elements and is unable to hold water;
  
• Overfarming - Overworking the land eventually drains the soil its nutrients, leaving it unable to produce crops;
  
• Poor irrigation practices - Bad irrigation can lead to waterlogging and salinisation of soil.
  
  Over one-quarter fo the Earth's land surface has suffered erosion and soil degradation.
  (top)
  
  Development: A process of economic and social transformation that defies simple definition. Though often viewed as a strictly economic process involving growth and diversification of a country's economy, development is a qualitative concept that entails complex social, cultural, and environmental changes. There are many models of what 'development' should look like and many different standards of what constitutes 'success'.
  (top)
  
  Ecological balance: Stability in an ecosystem achieved through the development of equilibrium among its various components. This does not imply that the community is static. It is subject to natural variations associated with ecological succession and other influences such as fire, disease and climate change, but the system is normally sufficiently elastic to make the necessary adjustments without major displacement of the balance. Human intervention that includes the introduction or removal of plants and animals, pollution of the environment and destruction of habitat is now a main cause of imbalance in many ecosystems.
  (top)
  
  Ecology: Originally defined by Ernst Haeckel in 1866, ecology is the study of the relationships that develop among living organisms and between these organisms and the environment.
  (top)
  
  Environment: A combination of the various physical and biological elements that affect the life of an organism. Although it is common to refer to �the� environment, there are in fact many environments eg, aquatic or terrestrial, microscopic to global, all capable of change in time and place, but all intimately linked and in combination constituting the whole earth/atmosphere system.
  (top)
  
  Environmentally-sound: The maintenance of a healthy environment and the protection of life-sustaining ecological processes. It is based on thorough knowledge and requires or will result in products, manufacturing processes, developments, etc. which are in harmony with essential ecological processes and human health.
  (top)
  
  Fallow: Land left unsown for a season, giving it a rest from cropping.
  (top)
  
  Fodder: Animal food which has been grown or collected specifically for livestock. For example, hay, straw, feed grain, grass, kale.
  (top)
  
  Food deficit: A shortage of foodstuffs in relation to the recommended food needed.
  (top)
  
  Food security: Access to sufficient nutritious food at all times.
  (top)
  
  Food surplus: A surplus of foodstuffs in relation to the recommended food needed.
  (top)
  
  Genetic engineering: Inserting genes from one source into another using molecular techniques.
  (top)
  
  Genetically modified organism (GMO): The product of genetic engineering.
  (top)
  
  GM foods: Foodstuffs that have had their genes changed (genetically modified - GM) in order to improve their productivity.
  (top)
  
  Green Revolution: The term given to the rapid increase in crop production brought about in the late 1950s and 1960s by a combination of increased fertiliser use and the introduction of new high yielding varieties of grain.
  (top)
  
  Herbicides: Chemicals used to kill plants and inhibit their growth.
  (top)
  
  Insecticides: Chemicals used to kill insects, especially those considered undesirable by farmers.
  (top)
  
  Irrigation: The provision of water for crops in areas where the natural precipitation is considered inadequate for crop growth.
  (top)
  
  Leguminous plants: A large group of pod-bearing plants (including acacia, peas, beans, alfalfa and clover) whose roots contain nodules with nitrogen-fixing bacteria, and are thus able to absorb nitrogen from the atmosphere and converted into a form useful to plants.
  (top)
  
  National conservation strategies: Plans that highlight country-level environmental priorities and opportunities for sustainable management of natural resources, following the example of the World Conservation Strategy published by the World Conservation Union (IUCN) in 1980. Though governments may support preparation for the strategies, they are not bound to follow IUCN's recommendations.
  (top)
  
  Organic farming: Production system that avoids or largely excludes the use of synthetically produced fertilizers, pesticides, growth regulators, and livestock feed additives. As far as possible, it relies on crop rotations, crop residues, animal manures, legumes, green manures, off-farm organic wastes, and aspects of biological pest control to maintain soil productivity and tillage, to supply plant nutrients, and to control insects, weeds, and other pests.
  (top)
  
  Organochlorides: A group of organic compounds that contain chlorine (Cl). They have a variety of forms and uses including aerosol propellants, plasticisers, transformer coolants (PCBs) and food packaging (PCVs), but their greatest use was as pesticides, in the form of DDT, Aldrine and Lindane. However, with time many pests have developed immunity to them and it has also become clear that the characteristics that made them good pesticides � persistence, mobility and high biological activity � also posed dangers for the environment. Organochlorides accumulate in the fatty tissue of animals, and through biomagnification in the food chain may reach toxic levels in predators. Because of side effects such as sterility, birth defects, cancer and damage to the nervous system, they have been banned or had their use severely restricted in most parts of the world.
  (top)
  
  Organophosphoruus compounds: A group of pesticides that work by blocking the central nervous systems of the organisms exposed to them. Malathion and diazonon are the most commonly used organophosphates. They are highly effective against insects, but break down rapidly in the environment and do not bioaccumulate. For these reasons, they are preferred over organochloride pesticides. Although generally considered safer than the organochlorides, they are highly toxic to humans and other mammals and may be carcinogenic.
  (top)
  
  Pastoral farming: A form of agriculture based on the herding of grazing animals such as cattle, sheep, goats and camels, common in the world�s arid regions.
  (top)
  
  Pesticides: Chemical products designed to kill or restrict the development of pests. They include fungicides, herbicides and insecticides. Pesticides range from relatively simple elements such as sulphur (S) to complex chemical compounds such as chlorinated hydrocarbons and may be broad-spectrum or narrow-spectrum agents. Pesticides also vary in their persistence in the environment, and in general, the longer they remain chemically stable the greater is their potential for environmental damage. The use of pesticides has undoubtedly benefited society, by preventing disease and improving the food supply. At the same time, ignorance of the environmental impact of pesticides, the indiscriminate use of certain products and inadequate control of the production and use of pesticides has created problems for wildlife and natural vegetation and has threatened human health.
  (top)
  
  Pesticides: Chemical products designed to kill or restrict the development of pests, pests being organisms considered undesirable by those using them.
  (top)
  
  Proper resource pricing: The pricing of natural resources at levels which reflect their combined economic and environmental values.
  (top)
  
  Salinisation: The build up of salts in soil as a result of the capillary flow of saline water towards the surface. A common problem in areas where the land is irrigated.
  (top)
  
  Shifting cultivation: A system of cultivation common in the tropics, whereby forests and grassland are cleared, usually by fire, which provides ash to fertilise the land. After a few years, when the soil is exhausted, the cultivators abandon the plot and move elsewhere.
  (top)
  
  Soil erosion: The removal of topsoil by water, wind and gravity. A natural process which can be hastened by human activity.
  (top)
  
  Subsidy: A financial benefit or form of assistance given to producers (e.g., grants, loans, tax allowances)which enables them to sell or export goods at less than their costs of production, thus creating unfair competition.
  (top)
  
  Subsistence farming: The production of sufficient food and other necessities to meet the requirements of a farm unit, leaving no surplus for sale and little for storage.
  
  Source: Many of these definitions have been taken from, or abridged from The Environment Dictionary by David D Kemp (Routledge, London, 1998).
  (top)
  
  Sustainable development: Sustainable development has as many definitions as subscribers. In essence, it refers to economic development that meets the needs of all without leaving future generations with fewer natural resources than those we enjoy today. It is widely accepted that achieving sustainable development requires balance between three dimensions of complementary change:

• Economic (towards sustainable patterns of production and consumption)
• Ecological (towards maintenance and restoration of healthy ecosystems)
• Social (towards poverty eradication and sustainable livelihoods)

For more details of how you can help, click here.