Do Now 4/20 HW change: 34.9 ONLY OBJECTIVE: Identify and describe the characteristics of major terrestrial and aquatic biomes TASK: Copy definition into notes: A biome is a group of ecosystems in the biosphere with similar abiotic and biotic components

So how many biomes are there? No fixed number 5, 7, 9, or more… depends on how specific you are We’ll look at 9….

What to do? Complete your chart as we discuss each biome.

Terrestrial Biomes Terrestrial biomes are land environments They are largely defined by patterns of precipitation and temperature.

Tundra Tundra comes from the Finnish word tunturia, meaning treeless plain. Extremely cold climate (covered by ice for > 6 months /yr) Low biotic diversity Permafrost Short season of growth and reproduction Energy and nutrients in the form of dead organic material Large population oscillations

Taiga The average temperature is below freezing for six months out of the year Drier than temperate forest There are not a lot of species of plants in the taiga because of the harsh conditions. Many coniferous trees. Needle- shaped leaves conserve water also known as the boreal forest..

Moderate temperature and rainfall Diversity of plant and animal species, especially deciduous trees (that lose their leaves in the autumn) Pronounced seasons Eastern US & Central Europe

Temperate Grassland Extremely fertile soil Dominated by grasses Semi-arid (10 – 30 inches of rain / year) “midwest”

Savanna Hotter & wetter than temperate grassland warm temperature year round Dry & Rainy “seasons” Plants of the savannas are highly specialized to grow in this environment of long periods of drought. Most of the animals on the savanna have long legs or wings to be able to go on long migrations Huge areas of savanna are lost to the Sahara desert every year because of overgrazing and farming.

Very Dry! (<10 in. / yr) Usually hot, but defined by precipitation – Antarctica is a desert too! Specialized plants adapted to low moisture

Tropical Rain Forest abundant precipitation ( > 100 in. / year) and year round warmth. No seasons: each species has evolved its own flowering and fruiting seasons. Canopy of tree cover Most biodiverse biome Many unique, specialized species

Aquatic Biomes Aquatic biomes are underwater, and there are only two major types: –Freshwater –Marine Earth is a blue planet: –70% of surface –Majority of organisms –Majority of photosynthesis –Abiogenesis / evolution

Freshwater Ecosystems Lakes, streams, rivers, marshes, and estuaries of all types. Great variety, due to abiotic factors like: –Salt concentration –Light availability –Dissolved O2, CO2, and other nutrients. Hypotonic environment.

Bull Falls, Shenandoah

Marine Ecosystems

Biome Review Tundra Taiga Temperate Deciduous Forest Temperate Grassland Desert Savanna Tropical Rain Forest Others? (Chaparral) Freshwater / Marine