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The term “heat island” refers to urban air and surface temperatures that are higher than nearby rural areas. Many cities and suburbs have air temperatures that are 2 to 10°F (1 to 6°C) warmer than the surrounding natural land cover. Figure 1 shows a city’s heat island profile.

Although marine species richness may only total 4% of global diversity, life began in the sea, and much of the diversity in the deep branches of life’s tree is still primarily or exclusively marine. For example, 35 animal phyla are found in the sea, 14 of which are exclusively marine, whereas only 11 are terrestrial and only one exclusively so.

World economic production has more than quadrupled since the early 1960s. Further economic growth is clearly desirable in developing nations in order to improve the well-being of over a billion people who are now living in desperate poverty.

Nitrogen is most commonly experienced in the form of molecular nitrogen (N₂) as a colorless, odorless and inert gas that constitutes about nearly ⁴/₅ths (78%) of air by volume. The French chemist Antoine Laurent Lavoisier named nitrogen azote, meaning “without life.”

Asphalt is a dark brown-to-black cement-like material obtained by petroleum refining and containing bitumens as the predominant component. Bitumen is a generic term for natural or manufactured black or dark-colored solid, semisolid, or viscous cementitious materials that are composed mainly of high-molecular weight hydrocarbons.

Variation in distribution and abundance of organisms is dependent on interactions between physical and biotic factors. “Bottom-up” effects refer to controls on the abundance and/or community structure of organisms that derive from supply of resources (light or nutrients for plants, prey organisms for animals) or from physical factors such as temperature of the environment.

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