The world's wild species provide ________ services that support our health and economic activities.
A country with a large percentage of its people younger than age 15 has high ________ .
Which country cut its birth rate in half through a strict one-child policy?
As countries become industrialized and economically developed, the population growth rate ________ .
increases temporarily before slowing down
Temperate deserts can be ________ .
hot during the day but cold at night
A community is debating about whether to allow drilling for oil in a nearby wildlife refuge. What principle should they apply to prevent and reduce harm?
The greatest threat to wild species is ________ .
habitat destruction, degradation, and fragmentation
What river feature is found in the source zone?
Crown fires usually occur in forests that ________ .
have not experienced surface fires for several decades
As moist air blowing inland from an ocean reaches a mountain range, ________ .
it rises, expands, and cools, losing moisture as rain and snow
The period of high birth rates in the United States between 1946 and 1964 is called the ________ .
Two-thirds of all fish extinctions in the United States since 1990 can be attributed to ________ .
The circulation of the atmosphere is powered by ________ .
At least 95% of the 2.6 billion people projected to be added to the world's population between 2013 and 2050 will live in ________ .
One important trend related to human population is that people are moving in large numbers from ________ to ________ .
rural areas; urban areas
For the past 200 years, human population growth has resembled a(n) ________ .
Today, forests in the United States ________ .
cover more area than they did in 1920
The greatest species diversity in a biome tends to be found ________ .
the transition zone between biomes
The world's 1,600 botanical gardens and arboreta contain about ________ of the world's rare and threatened plant species.
One strategy for reducing fire-related harm to forests and people who use or live in the forests is to ________ .
use prescribed burns to remove flammable small trees and underbrush in the highest-risk forest areas
Which portion of the open ocean is defined as the brightly lit upper zone?
What is an additional complication of extinction where new species are no longer evolving?
Studies attempting to estimate the monetary value of the ecosystem services provided by the world's forests have found that it is ________ .
hundreds of times more than their economic value in terms of lumber and other wood products
Debt-for-nature swaps can have a positive impact by ________ .
making it financially attractive for countries to protect their tropical forests
One advantage of mass transit rail for a city is that it ________ .
uses less land than roads and parking lots
What is the most accurate description of climate?
Averaged over the last 30 years, the average daily high temperature for June in an area is 82 °F.
Which method of logging is the least sustainable?
Smuggling wild animals around the world would most likely lead to ________ .
a decline in ecotourism
The reintroduction of ________ to Yellowstone National Park has contributed to a decline in the elk population and provided food for bald eagles and ravens.
After a forest has been cleared for logging, a(n) ________ may naturally develop.
A quarter to one half of all land animals and plants could go extinct by the end of this century because of ________ .
International treaties designed to protect endangered and threatened species can be difficult to enforce. What is the primary reason for this?
The lack of needed resources for enforcement
A lake with a large supply of nutrients is called ________ .
A population with a large percentage of people over age 65 will ________ .
A species is considered endangered if it ________ .
has so few individual survivors that the species could soon become extinct
What is the most important factor that directly affects death rates?
Life raft ecosystems are ________ .
areas where poverty levels are high and a large part of the economy depends on degraded ecosystem services
In Indonesia, Malaysia, and other areas of Southeast Asia, tropical forests are ________ .
being replaced by large plantations of oil palm
An age-structure diagram shows ________ .
the percentages of males and females categorized as prereproductive, reproductive, and postreproductive
Overgrazing can destroy riparian zones, which are ________ .
strips of vegetation along stream or rivers
Over time, many inland wetlands in the United States have ________ .
been drained or filled to grow crops
When using ________ , loggers cut intermediate-aged or mature trees in a forest singly or in small groups.
Estimated and predicted extinction rates are likely lower than in reality because of ________ .
the identification of only about 2 million of the worlds' 7-10 million species
When women have access to education and paid employment outside the home, ________ .
total fertility rates tend to be low
As commercially valuable large species are overfished, the fishing industry has ________ .
begun working its way down marine food webs by shifting to smaller marine species
The local climate in cities tends to be ________ than nearby rural areas.
Grasslands occur primarily in areas that are ________ .
too moist for deserts but too dry for forests
To halt population growth, total fertility rate has to drop to ________ .
Which of the following is a greenhouse gas?
The Coriolis effect is the result of the ________ .
rotation of the earth
Which species are especially vulnerable to extinction when their habitats are destroyed?
Curitiba, Brazil is an example of an eco-city because it banned cars in the downtown area and ________ .
planned construction with mass transit spokes connecting outlying districts to the center
What is the wooly opossum's niche in the tropical rain forest?
The equator is warmer than the poles because ________ .
sunlight hits the equator directly, but hits the poles at a low angle
Which characteristic most places the blue whale at risk of extinction?
What is the best method of reducing threats from invasive species?
Focus all efforts on preventive measures.
Returning a degraded habitat or ecosystem to a condition as similar as possible to its natural state is called ________ .
Mangrove forests grow ________ .
in coastal wetlands
________ is the most efficient and sometimes least-costly way to cut trees, but it can harm an ecosystem by causing increased erosion, sediment pollution in nearby waterways, and losses in biodiversity.
The ultimate goal for captive breeding programs at zoos is to ________ .