Chapter 9 Notes “Forest” Ecology Chapter 9 Notes “Forest”

I. Coniferous Forest

Location Primarily in the subarctic regions of North America, Europe and Asia In the Southern Hemisphere generally on high mountains, where conditions are similar to high northern latitudes Many are harvested due to the increasing need for wood

Climate: Summers are warm, lasting 2 to 5 months Winters are long, cold and dry with little sunlight Receives 40 to 200 cm of precipitation a year

Organisms Coniferous means “cone-bearing” Coniferous trees or Conifers are trees that produce seed cones They are not diverse and contain only a few species of trees Most common tree species: pine, hemlock, fir, spruce, & cedar Most are Evergreens Means they do not lose all their leaves at a given time each year They lose and replace leaves slowly throughout the year They share unusual leaves called Needles long and thin covered in thick waxy substance Help trees conserve water Help the trees shed snow during the winters Ferns, Lichens, and Sphagnum moss are plants that can grow in the dim light of the forest floor

Limiting factors = Harsh winters and nutrient poor soil Soil is poor and acidic due to conifer needles which are acidic and decompose slowly Snow acts as insulating blanket, trapping heat and preventing the ground from forming permafrost…which protects the roots of the trees Small Herbivores: Most are seed eaters Mice, squirrels, jays, other rodents and birds Insects are common in summer…due to the poor soil and drainage Large Herbivores: Moose, elk, beaver, snowshoe hare feed on plants and bark Predators: grizzly bears, wolves and lynx

II. Deciduous Forest

Location Grow at lower latitudes than coniferous forest Temperate zones- areas with lower latitudes, they have four well defined seasons Spring, summer, fall, & winter

Climate Temperatures vary greatly Summer temperatures can be as high as 30 degrees Celsius (86 degrees F) Winter temperatures can fall as low as –30 degrees Celsius (-22 degrees F) Precipitation usually falls as rain or snow depending on the season Receive 50 to 300 cm annually Falls fairly regularly throughout the year

Organisms Deciduous trees shed their leaves during a particular season of the year Growing season last about 6 months The tree grows quickly Produces and stores large amounts of food Autumn has shortening daylight and cooling temperatures which triggers the tree to change and shed its leaves becoming dormant This loss of leaves allows for the tree to conserve water during cold winter months Photosynthesis stops and tree no longer produces food Winter is survived by consuming food stored in its trunks, branches, and roots Spring is when the trees grow new leaves and photosynthesis begins again in preparation for the next winter Deciduous forest are more diverse than coniferous forest

Six most common types of tree species : Maple, oak, beech, ash, hickory, and birch The forest has three distinctive layers: Canopy: the highest layer, made up of branches and leaves of tall trees, captures most sunlight Understory: beneath the canopy, made up of younger, smaller trees and shrubs Forest floor: mosses, ferns and other low light plants Soil is enriched from leaves that fall from the trees which decay quickly in the warm humid summer months forming a humus layer Humus- home to many insects and other invertebrates that feed on abundant organic matter

Most common organisms in deciduous forest due to abundant food and many different habitats are: Decomposers such as: fungi Insects and other invertebrates Birds, mice and other small mammals White-tailed deer Reptiles and amphibians (in the warmer forest) Predators such as: wolves, mountain lions, birds of prey, foxes & migratory birds in the summer months

Human Impact Deciduous forest have been changed drastically due to human activities such as farming, orchards, and urban developing Two factors that have driven human consumption: Rich soil…its deep and fertile due to humus making it excellent farmland Trees…generally they are hardwoods making them better material than conifers for making furniture and flooring Because of this impact the forest regenerates slowly because many of the species dependant on the trees have disappeared Planted forest are known as monoculture forest Often very productive but have low biodiversity and are highly susceptible to diseases, parasites and pollution

III. Rain Forest

Location Located at latitudes near the equator Tropical zone

Climate Temperatures here average around 25 degrees Celsius year around (77 degrees F) This areas receives direct rays from the sun during most of the year Precipitation falls as rain except for atop high mountains Receives between 200 and 400 cm of rain annually Growing season can last 12 months No real difference in the seasons…has almost an unchanging climate Because of unchanging seasons, water and temperature are NOT limiting factors Soil Nutrients is the most common limiting factor

General Information Most diverse terrestrial ecosystem on Earth Biome with a dense canopy of evergreen broadleaf trees supported by at least 200 cm of rain annually May contain as much as 70% of all terrestrial species on Earth They only cover 6% of Earth’s land surface, but may contain 50% of Earth’s land biomass

Structure of Rain Forest Trees are the basis Thousands of extremely diverse species of trees Most common species: cypress, balsa, teak & mahogany Peter Ashton (British ecologist) found 700 species of trees in only 10 hectares (2.74 acres) of tropical rain forest in Borneo

Layers of the Rain forest: Emergent trees- extremely tall trees which grow past the canopy Upper Canopy- highest structure formed by the leafy tops of trees which reach as high as 25 to 30 feet Captures almost 99% of sunlight Lower Canopy- just below upper, made up of younger trees that have not reached their potential heights Understory & Forest Floor- made up of plants that are able to live in low light and nutrient poor soil Forest floor is sparse because it only receives about 1% of filtered sunlight Soil is poor in nutrients because the dead organic matter is recycled in days or weeks instead of years like in other biomes

Organisms Warm temperature and constant moisture are ideal conditions for decomposers such as: insects, fungi, and bacteria Because of the diversity in the rain forest most organic matter is held in its organisms causing the topsoil to be thin and poor in nutrients Most of the soil nutrients is found in the top 5 cm of soil

Roots are shallow to take advantage of nutrients in the thin topsoil Because of poor, thin topsoil layer most trees widen their trunks at the bases Buttresses: ridges of wood that support the trees at their base Roots are shallow to take advantage of nutrients in the thin topsoil Other plants use the trees for support Lianas: woody vines that grow up the sides of trees to reach sunlight in the canopy Epiphytes: plants that live entirely on the trunks or limbs of trees absorbing airborne nutrients and moisture Bromeliads and Orchids

Most organisms of the rain forest live in the canopy Arboreal: tree-dwelling organisms live their whole lives without ever touching the ground Animals diversity is caused by two main factors: Diversity in rain forest plants Wide variety of habitats that exist in the different levels of the forest Habitats vary from tree to tree and from one part of a tree to another part

E.O. Wilson (American biologist) found 43 species of ants on a single tree Terry Erwin (British ecologist) estimates that there may be over 30 million species of insects on Earth, mostly in the rain forest

Deforestation In 1950, over 10 percent of Earth’s land surface was covered by rain forest. Now they only cover about 6 percent of Earth’s surface and the area is decreasing This is due to the destruction of forest as a result of human activity Main cause of destruction of rain forest is the human population’s need for space and wood