Glossary N

The Environmental Glossary. Letter N +++ 'Nutrient', 'Nitrogen fixation', 'Natural gas'
German: Erdgas
Natural gas are underground deposits of gases consisting of 50 to 90 percent methane (CH4) and small amounts of heavier gaseous hydrocarbon compounds such as propane (C3H8) and butane (C4H10).
- Natural gas liquids: - Natural gas liquids (NGLs) : A Natural gas liquids (NGLs) is Those Hydrocarbons in natural gas that are separated as liquids from the gas. Includes natural gas plant liquids and lease condensate.
- Natural greenhouse effect : Natural greenhouse effect is the Heat buildup in the troposphere because of the presence of certain gases, called greenhouse gases.
A Natural resource is Materials in nature, like trees, that are necessary for life. Resources provide ingredients for food,
Natural resources are the earth"s natural materials and processes that sustain life on the earth and our economies .
The Natural Step Framework is a creative approach for addressing Environmental challenges based on consensus and systems thinking.

The Natural Variability is the inconstancy that is inherent or natural to the media, objects, processes, or biota being studied.

A Natural Ventilation is air circulation is provided by opening barn doors or windows and allowing the wind to draw through

A Negative Pressure is a condition that exists when less air is supplied to a space than is exhausted from the space, so the air pressure within that space is less than that in surrounding areas.

Net primary productivity is the (NPP) Rate at which all the plants in an ecosystem produce net useful chemical energy; equal to the difference between the rate at which the plants in