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Chapter 9 Forest Biomes Covers 30% of the Earth Contains 75 % of Earth’s Biomass 9.1 Coniferous Forest Limited to the Northern Hemisphere (far from the equator) High latitudes (closer to the Arctic) Summers are warm and last 2-5 months Winters are long and very cold 40-200 cm of precipitation (as rain and snow) per year 9.1 Coniferous Forest Coniferous means “cone bearing” Conifers (coniferous trees) producer seeds in cones Leaves have adapted to conserve water by producing long-thin with a thick waxy coat called needles 9.1 Coniferous Forest Tree is also a cone- shaped - the needles allow heavy snow to fall through the branches Conifers are “evergreen” they do not loose all their leaves in winter but keep them all year round 9.1 Coniferous Forest Examples of conifers: Hemlock, Spruce, Cedar, Pine Forests are not diverse – usually only one or two types of pine. Scotch Pine Soil is poor and very acidic Eastern Cedar Blue Spruce Hemlock 9.1 Coniferous Forest Plants: Ferns, Lichens and Sphagnum moss grown on forest floor Animals: Large herbivores – moose, elk Small herbivores – beaver, snowshoe hare, squirrel, mouse, blue jay Carnivores – grizzly bear, wolves, fox, weasel, lynx, owl, eagle 9.2 Deciduous Forest Deciduous tree sheds its leaves during the winter Temperature ranges from 30oC in summer to -30oC in winter Precipitation 50 – 300 cm (rain/snow) per year Forests found in the temperate zones – mostly Europe and North America Maple tree 9.2 Deciduous Forest Growing season is 6 months long Sunlight is used by chlorophyll in the leaves to make food Autumn has shorter days – chlorophyll fades –other pigments show through All pigments fade, leaves dry up and fall off tree 9.2 Deciduous Forest Deciduous forest has 4 layers: Canopy – top layer Understory – third layer Shrubs – second layer Floor – bottom Lots of biodiversity so lots of organic matter in the soil (humus-Ch 8) 9.2 Deciduous Forest Food web has many organisms: Decomposers (fungi and bacteria) Insects (bees, flies) and invertebrates (worms) Herbivores (deer, rabbits, mice) Carnivores (mountain lions, wolves, eagles, owls) 9.2 Deciduous Forest Human activity has shrunk the vast area that was the temperate deciduous forest. Two reasons: rich soil for farming and the trees for wood, fuel and paper Replanting trees does not restore the forest ecosystem 9.3 Rain Forest Tropical zone is located at or near the equator. Direct rays from the sun keep temperatures warm 25oC or higher Growing season is 12 months Precipitation 100-450 cm of rain a year 9.3 Rain Forest Dense canopy of evergreen broadleaf trees Contains 70-90% of all species on Earth Only 6% on the Earth’s surface 40% of the Earth’s biomass Most biodiverse biome 9.3 Rainforest Several levels: Emergent trees- top layer, 99% sunlight (50-60 m) Upper canopy – next layer – less than 1% filtered sunlight Lower canopy – third layer, less than 1% filtered sunlight Understory – fourth layer, dense shade Forest floor – little or no sunlight 9.3 Rainforest Top soil is thin – 99% of available nutrients in only 5 cm of top layer soil Tree roots are shallow and trees develop extra roots - Buttresses - to support the immense height Dead organic matter decomposes and is recycled quickly 9.3 Rainforest Most activity takes place in the canopy layer Many rainforest organisms never touch the ground Vast diversity of plant life leads to vast diversity of animals Habitats vary from tree to tree and level to level Complex food webs with many species interactions 9.3 Rainforest Greatest biodiveristy for plants, animals and insects Many species haven’t even been discovered yet Fungus beetle, toucans and howler monkeys spend their time in the upper canopy Blue bird-of-paradise travels from the lower canopy to the forest floor Margay cat hunts understory and forest floor Tapir lives on the forest floor 9.3 Rainforest Deforestation