The Biomes on Earth

Tundra

•Cold temperatures

•permafrost even in the summer

•10” of rain annually

•no trees, just grasses in the short summer

•small mammals, waterfowl, lots of insects

 

Coniferous Forest

•Long winters with short, cool summers

•10-40” of rain annually

•trees have needles to reduce water loss and shed snow

•larger mammals, migratory birds

 

Deciduous Forest

•Cold winters and warm summers

•40” of rain annually

•trees have broad leaves yet lose these in the winter when they become dormant

•larger mammals, migratory birds, insects, a few reptiles and amphibians

 

Grassland

•Cold winters and hot summers

•10-30” of rain annually

•grasses dominate, trees are found along the edge of waterways

•grazing mammals, birds, insects; known as our “breadbasket”

 

Desert

•Very hot and very cold

•10” of rain annually

•plants have spines instead of leaves to reduce water loss

•many plants store water in fleshy stems or roots

•small mammals, birds, reptiles

 

Savanna

•On average, warm temperatures

•20-60” of rain annually

•rainy vs. dry season

•mainly grassland with clumps of trees

•lots of large, grazing mammals, birds, insects, and reptiles

 

Tropical Rain Forest

•Warm temperatures

•80” of rain annually

•trees have broad leaves and epiphytes

•forest floor is dark because of dense tree cover and soil contains few nutrients

•huge diversity of all animals

 

Saltwater Ecosystems

Oceans

•Cover about 70% of the earth’s surface

•Distribute solar heat in their currents

•Part of the global water cycle

•Help regulate the earth’s climate

•Cycle nutrients as currents and tides move water from place to place

 

 

Estuaries

•Partially enclosed bodies of water

•Saltwater (from tides) and freshwater (from surface runoff) mix to form brackish water

•Shallow and warm

•Seagrasses provide food and habitat for fisheries and birds

 

 

Coastal Wetlands

•Salt marshes are located where land meets the sea

•Saltwater and freshwater mix to make brackish water

• Land is covered with saltwater most of the year

•Emergent grasses provide food and habitat for fisheries and birds

 

 

Mangrove Swamps

•Found along tropical coasts

•Salt-tolerant trees provide food and habitat for fisheries and waterfowl

 

 

Coral Reefs

•Found in shallow, clear, tropical waters

•Provide food and habitat for fisheries

•Help protect the coastline

•Remove carbon dioxide from the air

 

Freshwater Ecosystems

Lakes

•Oligotrophic - deep, steep banks, crystal clear water

•Eutrophic - shallow, gentle banks, murky water, lots of algae present

 

Rivers

•Headwaters merge to form tributaries which merge to form streams which merge to form rivers …

•Headwaters contain clear, cold, oxygenated water which gets murkier, warmer, and depleted of oxygen as the streams merge

 

 

Inland Wetlands

•Include marshes, swamps, floodplains, and bogs

•May be covered with water only part of the year

•Provide food and habitat for fish and birds

•Filter, dilute, and degrade toxins, excess nutrients, sediments, and other pollutants