Species richness decreases from the equator poleward Figure 2. Within this general pattern, certain geographical areas have notably high numbers of species, many found nowhere else in the world.
A biome is characterized by abiotic nonliving factors such as geography and climate and by biotic living factors such as plant and animal species. Life in any biome includes producers plants and other photosynthetic organisms and consumers organisms that obtain their energy from producers.
These consumers may be further classified as herbivores plant eaterscarnivores meat eatersor omnivores feed on a combination of animals and plants. In addition, all ecosystems are dependent on detritivores decomposers — bacteria and other microorganisms that obtain energy from breaking down organic matter.
The flow of energy from the sun through an ecosystem can be illustrated in a food chain, such as this generalized one: Energy is lost in the form of heat at each level of a food chain, which means that the number of individuals at each successive level decreases. For example, within a food chain there are always more producers than primary consumers, and more primary consumers than secondary consumers or tertiary consumers.
Decreasing available energy and population sizes in a food chain are illustrated by an energy or ecological pyramid: Image courtesy of Wikimedia. A food web, which illustrates the overlap between multiple food chains, more accurately captures the flow of energy in an ecosystem.
A food web shows overlap between multiple food chains in an ecosystem. Living organisms in any biome interact through a variety of relationships.
Organisms compete for food, water, and other resources. Predators hunt their prey. Some organisms coexist in mutually beneficial relationships symbiosiswhile others harm organisms for their own benefit parasitism.
Still others benefit from a relationship that neither helps nor harms the other organism commensalism. Biomes and their food webs can change as a result of natural hazards or human activities. Changes in environmental conditions may limit the availability of resources food, water, space or shelterreducing the number of organisms that can survive in a given environment.
A change at any level of a food web will impact all other organisms in that web in some way. Examples of keystone species include grizzly bears, sea stars, and sea otters. TUNDRA The tundra is a biome characterized by an extremely cold climate, little precipitation, poor nutrients, and a short growing season.
Other characteristics include low biodiversity, simple plants, limited drainage, and large variations in populations.
There are two types of tundra: Arctic tundra is located in the Northern Hemisphere; alpine tundra is located at high elevations on mountains throughout the world. Tundra is also found to a limited extent in Antarctica — specifically, the Antarctic Peninsula.
It extends south to the edge of the taiga a biome characterized by coniferous forests. The division between the forested taiga and the treeless tundra is known as the timberline or tree line. Location of arctic tundra across the Northern Hemisphere. The tundra is known for cold conditions, with an average winter temperature of degrees F degrees Cand an average summer temperature ranging from 37 degrees to 54 degrees F 3 degrees to 12 degrees C.
The growing season lasts from 50 to 60 days. The biome is also characterized by desertlike conditions, with an average of six to ten inches 15 to 25 cm of yearly precipitation, including snow melt. Winds often reach speeds of 30 to 60 miles 48 to 97 km an hour. Another hallmark of the tundra is permafrost, a layer of permanently frozen subsoil and partially decayed organic matter.
Only the top nine or ten inches of soil thaw, leading to the formation of bogs and ponds each spring.
Ice wedges in the permafrost can crack and cause the formation of polygonal ground.Sep 04, · Species unique to a single climate zone were mostly found in the maritime zone with nearly twice the number compared with other climate zones . Endangered Animals Some species of animal indigenous to the rainforest biome that are endangered are Bengal tigers, chimpanzees, poison dart frogs, the golden lion tamarin and the harpy eagle.
Abiotic Factors The tropical rainforest biome has very high precipitation levels and very high temperatures throughout the year. Study Biodiversity Test Flashcards at ProProfs - Biodiversity flashcards for chapters 34 and protected area that has a high concentration of endangered species.
Restoration ecology: restoring ecosystems. fire is essential to the biome, soil is thin acid. Tundra: . Grasslands and savannas together cover approximately 5% of Earth’s surface, and make soil and climate being the major limiting factors to their distribution. Natural savannas, Fewer species of both plants and animals can survive in cold.
Chapter 6 - Biomes. What is a Biome?, Forest Biomes, and Grassland, Desert, and Tundra Biomes a large region characterized by a specific type of climate and certain types of plant and animal communities Eurasia, South America and Africa.
Characterized by nutrient-rich soil that supports many grass species, a region that has cold winters. Vegetation zones are closely connected to climate zones. Climate, types of soil and landforms affect an area's vegetation. This chapter looks at the different types of vegetation zones of Australia and the main factors affecting them.