Biomes Notes

High plant density leads to varying shade levels.
- Plants adapt to maximize sunlight exposure through:
- Broad leaves.
- Great height.
- Climbing ability (e.g., vines).
- Other plants adapt to shade by relying on larger plants.
Animals are active year-round with specialized adaptations for different forest levels (ground, mid-tree, treetops).
Economic Importance: Rainforests provide valuable resources such as timber, medicinal plants, and raw materials like rubber and resins. They also support tourism through ecotourism initiatives.
Impact of Increased CO2: Increased CO2 levels can initially boost plant growth, but also lead to ocean acidification, disrupting marine ecosystems connected to the rainforest. Climate change-induced shifts in rainfall patterns can cause droughts affecting the rainforest's biodiversity.

Defined by less than 25 cm of rainfall per year.
Some deserts, like the Sahara, have as little as 2 cm of rain per year.
High insolation results in hot days and cold nights due to lack of water and plants.
Succulents, such as cacti, store water in fleshy stems and leaves.
Non-succulent drought-tolerant trees are also present.
Animals require little water and are often nocturnal.
Temperature varies considerably during the day, with very hot days and cold nights.

Characteristics of Desert Biomes:

Climate Precipitation: \textless 25 cm/year
Economic Importance: Deserts can be sources of minerals and energy resources. Tourism, particularly adventure tourism, also contributes to the economy.
Impact of Increased CO2: Increased CO2 can lead to desertification in already arid regions, making them less habitable for existing flora and fauna. Changes in precipitation patterns can disrupt fragile desert ecosystems.

Grasses have extensive root systems for quick recovery from drought, cold, or grazing.
Large grazers travel great distances to find food.
Small burrowing animals protect themselves from harsh weather and predators.
Humans rely on grasslands for food (wheat, corn, cattle, sheep).
Economic Importance: Grasslands are crucial for agriculture, supporting livestock farming and crop production. They also provide recreational and tourism opportunities.
Impact of Increased CO2: Increased CO2 levels can shift grassland composition, favoring certain grass species over others. Changes in temperature and precipitation can lead to decreased biodiversity and increased risk of wildfires.

Characteristics of Rain Forest Biomes

Climate Precipitation: > 200 cm/year.
Average annual temperature: 25°C to 30°C.
May have short dry season.
Plants
- Broad-leaved trees, evergreen and deciduous.
- Vines and shrubs.
- Air plants.
Animals
- Hummingbirds, parakeets, parrots, toucans.
- Snakes, lizards, frogs.
- Paca, agouti, peccary, armadillo, coatimundi.
- Monkeys, gorillas, jaguars, tigers.
Usually warm and moist throughout the year, but may be relatively dry for short periods.

Grassy regions with few or no trees because the quantity of water is too low to support tree growth.
Precipitation at least 20 cm per year, but not enough to support trees.
Average annual temperature ranges from 4°C to 30°C.

Characteristics of Grassland Biomes:

Trees lose their leaves each fall.
Found between latitudes 30° N and 60° N.
Moderate climate and longer growing season than taiga.
Distinct winter and summer seasons.
Light penetrates to the forest floor, supporting shrubs, mosses, lichens, and ferns.
Rich mixture of plants provides food and habitat for many kinds of animals.
Economic Importance: Deciduous forests provide timber, maple syrup, and recreational opportunities such as hiking and hunting.
Impact of Increased CO2: Higher levels of CO2 may initially boost tree growth in deciduous forests, but long-term effects include altered species composition and increased vulnerability to pests and diseases due to climate change-induced stress.

Characteristics of Deciduous Forest

Climate Precipitation: 75 to 150 cm/y.
Average annual temperature: 14°C to 27°C.
Well-defined summer and winter seasons.
Plants
- Broad-leaved deciduous trees.
- Mosses, lichens, ferns.
Animals
- Insects and birds; ground-dwelling birds (turkey, pheasant).
- Squirrels, rabbits, skunk, chipmunks

Evergreen trees/coniferous (needled) forests. - Located in colder climates (high latitudes), south of the tundra. - Cone shape of trees allows them to hold heavy snow without breaking. - Needles covered by a thick, waxy coat that minimizes water loss. - Soil is acidic because of falling needles. - Fewer plants than temperate deciduous forests. - Animals - Bears, moose, deer, lynx, wolverines, weasels, porcupines, and migratory birds. - Economic Importance: Taiga forests are a major source of timber and pulpwood. They also support hunting and trapping industries.
Impact of Increased CO2: Climate change is causing the taiga biome to shift northward, impacting tree species distribution and increasing vulnerability to insect infestations and wildfires.

Characteristics of Taiga Biomes

Climate Precipitation: 40 to 100 cm/y
Average annual temperature: -5°C to 5°C
Long, cold winters and short, cool summers.
Plants
- Evergreen coniferous trees (spruce, fir, pine).
- Some deciduous trees (birch, aspen).
Animals
- Bears, wolves, lynx, wolverines.
- Moose, deer, elk.
- Beavers, porcupines, snowshoe hares.
- Migratory birds (warblers, finches, sparrows).

Open, windswept, and often soggy plains.
Located at high latitudes, above the taiga.
Permafrost: soil that remains permanently frozen.
Short growing season (only a few weeks).
Few species of plants and animals.
Animals - Lemmings, voles, weasels, arctic foxes, snowshoe hares, ptarmigan, snowy owls, and musk oxen. - Lichens are important because they survive the harsh winters. - Economic Importance: Tundra regions contain deposits of oil and natural gas. They also support subsistence hunting and fishing by indigenous communities.
Impact of Increased CO2: Warming temperatures are causing permafrost to thaw, releasing methane (a potent greenhouse gas) and accelerating climate change. This also threatens infrastructure and habitats adapted to permafrost conditions.

Characteristics of Tundra Biomes