Chapter 55

Question 1

desertification

Answer 1

A process in which large tracts of subtropical forest are cleared and overused, the groundwater table recedes to deeper levels, less surface water is available for plants, soil accumulates high concentrations of salts, and topsoil is eroded by wind and water.

Question 2

overexploitation

Answer 2

The excessive harvesting of an animal or plant species, potentially leading to its extinction.

Question 3

hydrologic alterations

Answer 3

Human-induced changes in the pathways through which water moves in the hydrologic cycle.

Question 4

habitat fragmentation

Answer 4

A process in which remaining areas of intact habitat are reduced to small, isolated patches.

Question 5

pollutants

Answer 5

Materials or energy in a form or quantity that organisms do not usually encounter.

Question 6

acid precipitation

Answer 6

Rainfall with low pH, primarily created when gaseous sulfur dioxide (SO2) dissolves in water vapor in the atmosphere, forming sulfuric acid.

Question 7

invasive species

Answer 7

A nonnative species that can occupy a wide range of habitats and competitively exclude native species from those habitats.