If resources become limited, population growth rate slows and eventually stops; this is known as logistic population growth

Plants: mostly herbaceous, consisting of mixtures of mosses and grasses, forms, shrubs, trees and lichens. permafrost restricts the graph of plant roots (permanently frozen layer of soil)

Precipitation: 20-60 cm annually (exceed 100 cm in alpine tundra)

Animals: large grazing musk oxen are resident, while caribou and reindeer are migratory. predators include bears, wolves, and foxes. birds migrate for summer nesting

locations: covers expansive ares of the arctic. 20% of earths land surface

Plants: distinct vertical layers. dominant plants are deciduous trees

Animals: many mammals hibernate in the winter while many birds migrate to warmer climates. mammals, birds, and insects make use of all the vertical layers of the forest

Plants:dominated by cone-bearing trees, such as pine, spruce, fir, and hemlock. some of which depend on fire to regenerate

Precipitation: annually the range is 30 to 70 cm and periodic droughts are common

Animals: migratory birds, moose, brown bears, and Siberian tigers

locations: extending in a broad band across northern North America and Eurasia to the edge of the arctic tundra (largest terrestrial biome on earth)

Plants: dominant plants are grasses and forms. adapted to droughts and fires

Animals: large grazers such as bison and wild horses. inhabited by wide variety of burrowing mammals such as prairie dogs in North America

Precipitation:highly seasonal, with relatively dry winters and wet summers

locations: South Africa, Hungary, Russia, Argentina, Central North America

Plants: dominated by shrubs and small trees along with many kinds of grasses and herbs. plant diversity is high

Animals: native mammals include browsers such as deer and goats that feed on twigs and buds pf woody vegetation, and high diversity of small mammals. chaparrals support many kinds of amphibians, birds, insects and reptiles

locations: this biome occurs in midlatitude coastal regions on several continents

Plants: scattered trees found at different densities, often thorny with small leaves, well adapted to dry conditions

Animals:large plant eating mammals like zebras, and predators, including lions and hyenas. dominant herbivores are insects

Plants: dominated by low, widely scattered vegetation including succulents such as cacti and shrubs

locations: occur in bands near 30 degree north and south latitude in the interior of continents

Plants: vertically layered environment, abundant vegetation broadleaf evergreens are dominant

Animals: home to millions of species including amphibians, birds, and other reptiles, mammals, and anthropods, are adapted to the vertically layered environment and often inconspicuous

Chemical Characteristics: except in ares of organic enrichment, oxygen is usually present at sufficient concentrations to support diverse animal life

Physical Characteristics: consists of the sea floor below the surface waters of the coastal, or neurotic zone and the offshore, pelagic zone

Chemical Characteristics: corals require high oxygen levels and are excluded bu high inputs of fresh water and nutrients

Physical Characteristics: formed largely from the calcium carbonate skeletons of corals. shallow reef building corals live in the photic zone of relatively stable tropical marine environments with high water clarity, primarily near islands and on the edge of some continents

Chemical Characteristics: oxygen levels are generally high, nutrient concentrations are generally lower than in coastal waters

Physical Characteristics: a vast realm of open blue water, constantly mixed by wind driven oceanic currents

Chemical Characteristics: oxygen and nutrient levels are generally high and are renewed with each turn of the tides

Physical Characteristics: periodically submerged and exposed by the tides, twice daily on most marine shores

Chemical Characteristics: salinity varies specially within estuaries, from nearly that of fresh water to that of seawater. salinity also varies with he rise and fall of the tide

Physical Characteristics: transition area between land and sea, seawater flows up the estuary channel during a rising tide and flows back down during the falling tide

Chemical Characteristics: the salt and nutrient content of streams and rivers increases from the headwaters to the mouth

Physical Characteristics: most dominant characteristics include speed and volume of flow

Chemical Characteristics: because of high organic production by plants and decomposition by microbes and other organisms, the water and soil is low in dissolved oxygen

Physical Characteristics:habitat that is inundated by water at least some of the time and that supports plants adapted to water-saturated soil

Chemical Characteristics: the salinity, oxygen concentration, and nutrient content differ greatly and can very with season

Physical Characteristics: ranges from ponds a few square feet to covering thousands of square kilometers. light decreases with depth creating stratification

Global air circulation and precipitation is initiated by intense solar radiation near the equator

Latitudinal Variation in sunlight intensity is caused by earths curved shape

Global air circulation and precipitation is initiated by intense solar radiation near the equator

Seasonal Variation in sunlight intensity because earth is tilted on its axis relative to its plane of orbit around the sun, the intensity of solar radiation varies seasonally. The Coriolis effect, an effect whereby a mass moving in a rotating system experiences a force (the Coriolis force ) acting perpendicular to the direction of motion and to the axis of rotation. On the earth, the effect tends to deflect moving objects to the right in the northern hemisphere and to the left in the southern and is important in the formation of cyclonic weather systems.

Mountains influence air flow. the Rain Shadow Effect, An area having relatively little precipitation due to the effect of a topographic barrier, especially a mountain range, that causes the prevailing winds to lose their moisture on the windward side, causing the leeward side to be dry.

The environment limits population growth by changing birth and death rates

In the presence of abundant resources, populations can grow at geometric or exponential rates

Global human population growth amounts to around 83 million annually, or 1.1% per year. The global population has grown from 1 billion in 1800 to 7.616 billion in 2018. It is expected to keep growing, and estimates have put the total population at 8.6 billion by mid-2030, 9.8 billion by mid-2050 and 11.2 billion by 2100. Many nations with rapid population growth have low standards of living, whereas many nations with low rates of population growth have high standards of living.