Section #2: Forest Biomes

Forest Biomes Most widespread Most diverse Trees need lots of water, so rainfall must be plentiful Temperatures range from mild (coniferous forests) to hot (tropical rainforests)

Tropical Rain Forests General Info Located in a belt around the Earth near the equator Help regulate work climate and play a vital role in the N, O, & C cycles Always humid & warm year-round Get 200-450 cm of rain each yr. Receive the sun’s direct rays throughout the yr.

Tropical Rain Forests Diversity of Life The climate (high avg. rainfall and temps year-round) allow for an enormous number of plant & animal species to survive in the forest – over ½ of all species on Earth in fact

Tropical Rain Forests Nutrients The soil in this forest is surprisingly poor & thin Most nutrients are found in the plants, not the soil Decomposers quickly break down dead organisms & return the nutrients to the soil, but plants will quickly absorb them Water run-off is almost completely pure & free of nutrients Soil would not support crops very long after slash-n-burn

Tropical Rain Forests 4 Main Layers Emergent Upper Canopy Lower Canopy Understory

Tropical Rain Forests Emergent Layer top layer consists of the tallest trees (60 -70 m high) tree trunks are huge (5 m in circumference) grow up to reach direct sunlight home of eagles, bats, monkeys, snakes

Tropical Rain Forests Upper & Lower Canopy primary layer trees grow more than 30 m tall & absorb 95% of the sunlight lower canopy receives less light home for most animals because of the abundant flowers & fruits that grow there (food source)

Tropical Rain Forests Epiphytes plants that use the entire surface of a tree as a place to live need to be high up to reach sun needed for photosynthesis absorb water & nutrients that run down the tree after rains example = orchids

Tropical Rain Forests Understory lower layer very little sunlight trees & shrubs are adapted to shade (have large, flat leaves to collect the little sunlight that filters through) maximum growth is 3.5 m tall

Threats to Tropical Rain Forests habitat destruction 100s of acres are cleared for logging operations, agriculture, or oil exploration every minute species are disappearing native people are losing everything they need to survive illegal trade of exotic plants & animals

Temperate Rain Forests General Info Located in North America, Australia, & New Zealand Large amounts of precipitation High humidity Moderate temps

Pacific Northwest nearby Pacific Ocean waters keep the temperature regulated so it never freezes even at the high latitude

Temperate Deciduous Forests Located in North America, Australia, Europe & Asia between 30° & 50° north latitude range of temps can be extreme, from 35 ° C in summer to just below freezing in winter

Temperate Deciduous Forests growing season lasts from 4-6 months moist, receive 75 - 125 cm of precipitation annually

Deciduous Forests in fall, trees stop photosynthesis, leaves change colors, & drop to forest floor to decompose this contributes to the deep, rich soil of the forest

Temperate Deciduous Forests Plants plants grow in layers canopy of tall trees includes maples, oaks, birch, & hickory understory gets more light & contains the shrubs, ferns, mosses, & herbs

Temperate Deciduous Forests Plants after a dormancy period through the cold winter months, trees grow new leaves, the seeds & bulbs germinate, & the rhizomes (underground stems) grow new shoots

Temperate Deciduous Forests Animals support a variety of animals that are adapted to use the forest plants for food & shelter most birds use the safety of the canopy for shelter & nesting, but migrate south for food during the winter months

Taiga Forests General Info band of coniferous forests in the Northern Hemisphere (just below the Arctic Circle) long winters (6-10 months) of below freezing temps & little precipitation short growing season in the summer – more sunlight & precip

Taiga Forests Plants forest floor is dark & has little vegetation conifers have needle-shaped leaves (narrow & waxy) to retain moisture when water in ground in frozen cone shape helps shed snow so branches don’t break

Taiga Forests Animals summertime insects & fish attract birds, most of which migrate south for the winter shrews & rodents burrow underground during the winter since the deep snows insulate the ground some creatures have adapted to grow white fur for winter to camouflage then in the snow