Science 14: Chapter # 14 Ecosystems and Biomes. Baier's Science 14 1

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1 Science 14: Chapter # 14 Ecosystems and Biomes Baier's Science 14 1

2 Ecosystems An ecosystem is made up of both the living and non-living components of an environment All of the living components of an ecosystem are called the biotic community All of the non-living components of an ecosystem are called the abiotic environment The number and type of living things in an area depend on many abiotic factors, like: Temperature Amount of Precipitation Type of Soil Baier's Science 14 2

3 Ecosystems An ecosystem exists if the following statements are true about a group of populations: Living things interact with one another Living things interact with other species Living things interact with the abiotic environment Baier's Science 14 3

4 14.2 Climate and Land Ecosystems The climate of an area is its average weather conditions based on long-term records Climate determines what kinds of plants and animals can live in particular area For each type of climate: Temperature is within a certain range in each season The average annual precipitation is within a certain range Climate is determined by: A) Topography An area s physical features Ex. Mountains, Lakes, Rivers, Hills etc. B) Altitude (Elevation) The height of an area above sea level C) Latitude How far north or south you are from the equator Baier's Science 14 4

5 14.2 Climate and Land Ecosystems Baier's Science 14 5

6 14.2 Climate and Land Ecosystems Baier's Science 14 6

7 14.3 Location & Soil The same factors that affect climate also affect the soil in an area, which then affects the kinds of plants and animals in an area Soil is the thin layer of rock fragments of different sizes that covers the land The smallest particles that make up soil are called clay, then silt, then sand, then gravel Good soils contain nutrients, trap water and gives plants a firm base in which to grow Baier's Science 14 7

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9 14.3 Location & Soil Soils also contain animal wastes and the remains of decaying organisms Decomposers convert these materials into humus Humus consists of trapped moisture, fibres, soil particles and a black, sticky liquid that is really the decayed remains of organisms Humus binds soil particles together in soil crumbs Soil crumbs are good because: The spaces between crumbs leave rooms for plant roots The spaces between crumbs allow air to get into the soil They keep soil moist but the spaces allow excess water to drain away They are less likely to be blown away by wind Humus prevents the washing of nutrients out of the soils by leaching Baier's Science 14 9

10 Biomes The types and number of plants and animals found in an area are determined by the region s climate, elevation, temperature and soil A large geographic area with distinct plants and animals due to climate, elevation, soil and temperature is known as a biome Baier's Science 14 10

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12 Biomes Alberta has be separated into four main biomes A.Grasslands B.Boreal Forest C.Mountain and Foothill D.Parklands Baier's Science 14 12

13 Biomes A) Grassland (Prairies) Lowest precipitation Drying winds Summers are hot and winters are cold Snowstorms in spring, drought in summer Mixed grasses grow in clumps in undisturbed areas Contains animals like the burrowing owl, ground squirrels, rattlesnakes, swift fox and pronghorn Baier's Science 14 13

14 Biomes B) Parkland More precipitation than grassland The summers are cool and the winters are colder Contains plants like aspen trees and grasses Contains animals like deer, Baird s sparrows and redtailed hawks Baier's Science 14 14

15 Biomes C) Boreal Forest More precipitation than grassland Winters are long and cold, summers are cool with long days Soils thaw completely during spring and summer Acidic soil that decomposes organisms slowly Mixed forests of aspen, spruce and pine trees Contains animals like moose, snowshoe hares, lynx, wolves, owls, mosquitoes and caribou Baier's Science 14 15

16 Biomes D) Mountain and Foothill Extreme variations in temperature and amounts of precipitation due to differences in altitude over short distances At high elevation climate is colder in both summer and winter (short growing season) Contains plants like coniferous trees up to the tree line Contains animals like elk, Baier's Science moose and black bears

17 14.5 What Threatens Biodiversity? Biodiversity (diversity) is a word used to describe the number and variety of living things in an area Extinction is the elimination of a species from Earth that lowers biodiversity Species at risk are those species that are in danger of becoming extinct Baier's Science 14 17

18 14.5 What Threatens Biodiversity? By changing habitats that make up biomes, humans have affected where animals can and cannot live Human activities that have impacted biodiversity: Filling in wetlands Clear cutting forests Ploughing grassland and putting up fences Damming or diverting rivers Building highways Baier's Science 14 18