ABSTRACT
Greenhouse impacts are therefore particularly relevant to appliances that consume energy during their life, such as water and space heaters, stoves and refrigerators. The choice of fuel is particularly important, with large differences in greenhouse gas generation between alternatives such as gas and electricity. The most common sources of water pollution are discharges from industrial processes, household sewerage, storm-water drains and run-off from agriculture. Water pollution can have a visual impact. Air pollution has reduced significantly in many developed countries following the introduction of environmental regulations, emission controls and lead-free petrol. Pollution from diesel engines is also a cause for concern because of the growing number of diesel-powered small commercial and four-wheel-drive vehicles. Land degradation concerns the adverse effects that various uses of land by humans have had on the environment. These effects include reduced soil fertility, soil erosion, salinity of land and water, weed invasion, removal of topsoil and deforestation.
