What are the 7 major land biomes? Please give the basic characteristics for each.

According to my dictionary a biome is a "large geographical area of distinctive plant and animal groups, which are adapted to that particular environment." 

Desert:  These desert biomes receive less than 25 centimeters of rain per year; plants and animals that do not require much water and can adapt to extremely hot temps during the day and cool to cold night time temps. 

Forests:  Plants in a deciduous forest create many different habitats. Different species of birds live in different parts of the forest, eating the insects and fruits in their specific areas. Mammals such as chipmunks and skunks live in deciduous forests. In a North American deciduous forest you might also see wood thrushes, white-tailed deer, and black bears.  The Coniferous forest, also known as a taiga, is full of tall, sturdy evergreen trees that don’t shed their leaves in the winter.  The taiga is not as dry as a desert or a grassland biome.  It is full of mammals, reptiles, insects, and all sorts of wildlife. Tropical forests receive more rain yearly and have a huge canopy of leaves covering the forest floor.  The most varied and unique wildlife lives in the tropical forest than in any other type of biome.

Tundra:  This biome is cold and windy.  The tundra gets deep snows in the winter and the ground remains in a state of permafrost.  The plant life includes: mosses, grasses, shrubs, and dwarf forms of trees, such as willows and birch. Most of the plant growth takes place during the long days of the short summer season. North of the Arctic Circle, the sun does not set during midsummer.  I spent the summer in Alaska year or so ago and it is beautiful tundra with beautiful birds, insects, caribou, foxes, wolves, Arctic hares and bears.   No tics and no snakes live in the tundra. 

Grasslands: Temperatures here are milder than they are in a desert. The winds are strong can cause damage to crops and homes.  The soil supports grasses but not trees.  Many mammals and birds live in this biome as well as insects, reptiles

Savanna (grasslands): Grasslands receive more rain than deserts.  However, they don’t get enough rain for large trees to grow.   These biomes are generally located in the middle latitudes of the planet and covered with grasses and non woody plants.  The Savanna grasslands receive about 25-75 centimeters of precipitation each year.  There is a large variation of weather patterns in these biomes such as tornados and droughts.

Water biomes:  Marine biomes consist mainly of salt water environment of the ocean.  It is home to a number of different ecosystems. water temperature and the amount of sunlight determine what types of organisms can live in different areas of the biome.  There is a transition near coastal areas called estuaries where the fresh water and salt water meet.  There are a lot of animals living in this area like worms, clams, fish, crabs and plant life.  The estuaries give way to rivers, ponds, lakes and freshwater biomes.  Birds, deer, foxes, frogs, and all types of wildlife live near these fresh water biomes and fish, and amphibians live in the fresh water.

Mountains: This biome consists of rocky elevations and a variety of temperatures, precipitation and wildlife.  They consist of forests, water biomes, and tundra.