L-O

Land cover

The observed biophysical cover on the earth's surface, e.g. grassland, forest, croplands (6)

Land use

The ways in which humans make use of land; the arrangements, activities and inputs by people to produce, change or maintain a certain land cover type (6)

La niña

Climate pattern caused by unusually cool temperatures in the pacific ocean (10)

Leachate

Highly concentrated liquid pollutant that seeps from solid wastes into soil (7)

Leaching

Process whereby liquids seep out or are washed out by rain into the soil below (1)

Life expectancy

Average number of years that a person may expect to live (3)

Liquid waste

Human excreta (both faeces and urine), industrial wastewaters, and other forms of waste from water-using activities (7)

Mega-city

Urban area of greater than ten million people (5)

Migration

Movement of people from one place to another (5)

Millennium development goals (MDGs)

Eight international development goals that were established following the millennium summit of the united nations in 2000 to be achieved by 2015 (3)

Mitigation (of climate change)

Reducing the causes of climate change e.g. by reducing greenhouse gas emissions (12)

Noise pollution

Unacceptable levels of noise in work, residential and recreational places (7)

Non-point source (of pollution)

Also known as diffuse pollution; a source of pollution that is indistinct or extends across a wide area and where the exact point of origin cannot be easily identified (7)

Non-renewable resources

Resources that cannot be replenished by natural means at the same rates that they are consumed (1)

Organic matter

Anything derived from living organisms such as human and animals wastes, decaying plants, food waste (7)

Overfishing

Catching fish at faster rate than they can reproduce (1)