Biomes Flashcards
What is a biome?
a large region that has a characteristic climate and native species composition.
What 3 variables drive the formation of a biome?
Water/precipitation
Temperature
History -> soil conditions
What are the 4 soil horizons from top to bottom?
O (LFH), A, B, C
What is in the O soil horizon?
Organic material that is freshly fallen at the surface to partially decomposed material a little deeper
What is in the A soil horizon?
Minerals, clay, slit, sand with indiscernible decomposed material
What is in the B soil horizon?
Clay, humus, materials leeched from A horizon, often has plant roots
What is in the C soil horizon?
Weathered parent material that was the early part of the biome, bedrock
What is the difference between an ecosystem and a biome?
A biome is much larger, and can contain many ecosystems. Can also appear to be one giant ecosystem
Which 2 biomes are only found in the northern hemisphere and why?
Tundra and Boreal forest. There is no land mass in the south at the conditions for these biomes to form, and Antarctica is too dry and cold to be considered a tundra
What determines the biome that forms if there is overlap in the climate conditions?
The history, the soil conditions will determine the biome.
What kind of climate and soil conditions does the tundra biome have?
Cold and dry, which short summers and little evaporation of precipitation. Cold soil with low decomposition results in accumulation of organic matter (peat and humus). Soil is solid on top of a layer of permafrost. Landscape shaped by freeze/thaw processes.
What kind of plant and animal life is found in the tundra biome?
Plants have most biomass below the ground, mostly perennial herbaceous plants. Animals: not a lot of diversity , mostly large and small mammals, birds, and insects in high abundance
What are the human impacts on the tundra biome?
Oil and gas exploration, airborne toxin fallout, permafrost and decomposition rate alteration from increasing temperatures, CO2 production
What kind of climate and soil conditions does the boreal forest biome have?
Winters longer than 6 months, cold and wet, low evaporation results in accumulation of water, low decomposition, acidic soils
What kind of plant and animal life is found in the boreal forest biome?
Plants: Slow growing plants adapted to long cold winters with little nutrients, mostly conifers
Animals: large and small mammals, migratory birds, insects
What kind of climate and soil conditions does the temperate forest have?
Warm and wet, heavy precipitation in fall, winter, and spring. Neutral or slightly acidic soil that are rich in organic matter, fertile
What kind of plant life does the temperate forest biome have?
Large trees with large leaves that are vertically stratified.
What kind of climate and soil conditions does the temperate grasslands biome have?
Wetter than deserts, but droughts are still common. Most rainfall is during the summer. Soils are deep, basic or neutral and fertile, large amounts of undecomposed organic matter, thick A horizon
What kind of plant and animal life does the temperate grassland biome have?
Plants: herbaceous vegetation is dominant, most biomass underground.
Animals: smaller animals, once supported large herds of herbivores
What are the human impacts on the temperate grasslands biome?
Is now an endangered biome from agricultural development Most fertile farmlands, but unsustainable from soil loss and irrigation
What 4 factors control biomes?
Nutrients, Energy, Water, Temperature (NEWT)
What is an ecozone?
A biome based off the evolutionary history of the species there
What is an ecoregion?
A smaller area within an ecozone that takes the soil into account
