Chapter 7 Part III: Biomes

Transcription

1 Chapter 7 Part III: Biomes

2 Biomes Biome: the major types of terrestrial ecosystems determined primarily by climate 2 main factors: Depends on ; proximity to ocean; and air and ocean circulation patterns Similar traits of plants & animals for biomes of different parts of world; because of similar climate & evolutionary pressures ( )

3 Climate and Animal Size Organisms with a size have a surface area to volume ratio, because volume increases by the cube of the radius, whereas surface area increases by the square. Animals that live in climates often have body sizes so that they retain heat.

4 Biomes Earth's major biomes. tropical rain forest tropical deciduous forest tropical scrub forest tropical savanna desert chaparral boreal forest (taiga) temperate grassland arctic tundra temperate deciduous forest

5 Vegetation Patterns

6 Biomes Precipitation & temperature are the major factors influencing the distribution of biomes.

7 North American Biomes Red Text = Soil Types

8 Biomes have similar effects on general locations of biomes. This view does not take into account global air circulation patterns. Fig. 7 13

9 Desert Biomes Tropical Desert Temperate Desert Polar Desert

10 Characteristics: Desert Biomes typically annual precipitation; sparse, widely spaced, mostly vegetation Cover of land surface, especially at 30 N and 30 S latitude; largest deserts on of continents; plants either are typically rooted shrubs with leaves, succulants, or short lived species that flourish after rain; animals are typically & have physical adaptations for conserving water & dealing with heat.

11 Grassland, Tundra, & Chaparral Biomes Zimbabwe Kansas Alaska

12 Grassland Biomes Characteristics: sufficient rainfall to support grass, but often too for forests; mostly found on of continents; maintained by seasonal, grazing, & periodic that prevent invasion by shrubs & trees; plants include high diversity of grasses & herbaceous plants that typically have broad distributions & that have to drought, grazing, & fire; animals include large & small herbivores, along with predators adapted to feed on these herbivores. Chaparral Temperate Grassland

13 Forest Biomes Brazil Tennesee Russia

14 Forest Biomes Characteristics: sufficient rainfall to support growth of trees; three types: - tropical, typically evergreen trees with high diversity; - temperate, typically broadleaf tree with moderate diversity; - boreal, typical (needle leaves) with low diversity. community of plants & animals typically distributed in various layers: - understory of herbaceous plants & shrubs; - Sub-canopy of tree saplings; - canopy of full grown trees. Tropical Boreal

15 Mountain Biomes diversity of habitat because of diversity of altitude, slope orientation, corresponding, & soil over short distances; complex patterning of vegetation; make up of Earth's surface; each (300 ft) gain in elevation is approximately equal to a (62 mi) change in latitude; mountain regions contain majority of world's : elevation above which trees do not grow; : elevation above which there is permanent snow; important as for lowlands.

16 Soils, Nutrients, and Biomes Nutrient all affect the amount of available nutrients in an ecosystem. Biomes that have productivity have nutrient content in the soil if there is not an influx of nutrients. Example: and the have poor soil.

17 Soils, Nutrients, and Biomes However, ecosystems with very productivity also have a uptake of nutrients. So rainforests, which are the most productive ecosystem have very soil due to the rapid uptake of nutrients. (All the nutrients are found in the rather than in the soil.) Poor soil with low nutrient content. Soil high in organic matter has a darker color.

18 Soils, Nutrients, and Biomes Grasslands have nutrient soil because the have both a good growing season, which has a productivity, and an off-season with decomposition of organic matter which allows for a build-up of nutrients in the soil.

19 Biome Biomass Nutrient Availability Explanation Grassland Medium High Productive growing season. Build-up of nutrients during cold and or dry season (low Desert Low Low Inadequate water for living things Rainforest High Low Rapid nutrient uptake Wetlands High High Shallow, warm water. Influx of nutrients from streams.