Unit 3 - Ecology. Section 3 - Canada s Biomes and Climate Change. Watch: An Introduction to Biomes. Unit 3 - Ecology 1 / 19

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1 Unit 3 - Ecology Section 3 - Canada s Biomes and Climate Change Watch: An Introduction to Biomes Unit 3 - Ecology 1 / 19

2 Ecosystems can be grouped into larger categories called biomes. A biome is a collection of ecosystems that are similar or related to each other, usually in the type of plants they support. Biomes take into account not only biotic factors, but also abiotic factors such as average temperatures and the length of the seasons. Canada can be organized into four major biomes. Unit 3 - Ecology 2 / 19

3 The Tundra Biome Canada s northernmost biome is called a tundra. What distinguishes the tundra from the other biomes is particularly the length of the growing season, due to its cold temperatures. Plants must fight to grow in permafrost, a layer of soil that never thaws. Plants usually extend their roots in the layer of soil that lies above the permafrost, called the active layer. This layer thaws in the summer. Because of the permafrost, large trees cannot grow in the tundra. Unit 3 - Ecology 3 / 19

4 Summary of the Tundra: Abiotic factors Communities - very low temperatures - rapid-flowering plants - short growing season - mosses and lichens - permafrost layer beneath soil - caribou and arctic wolves - low precipitation - wolverines and ptarmigans Unit 3 - Ecology 4 / 19

5 The Boreal Forest Biome South of the tundra is the boreal forest biome. The boreal forest is found in every province and makes up approximately 80% of the forested areas. The boreal forest is dominated by conifers, which are trees with needle-shaped leaves. These trees dominate the boreal forest because they are very well adapted to extreme climates. The thin needle-like leaves lose very little water, making them suitable for the harsh winter and summers. The forest floor is very shaded and only shade-loving plants can survive, such as moss and ferns. Also, only seed eating animals and various herbivores can survive, such as squirrels and deer. Unit 3 - Ecology 5 / 19

6 Summary of the Boreal Forest: Abiotic factors Communities - no permafrost - coniferous trees - changeable weather - seed-eating birds - soil contains some water - squirrels, voles, and hares - precipitation 40 cm/y or more - grey wolves Unit 3 - Ecology 6 / 19

7 The Temperate Deciduous Forest Biome In Eastern and Central Canada is the temperate deciduous forest biome. This biome is dominated by deciduous trees such as maples and oaks. The deciduous trees have broad leaves that maximize light capture for photosynthesis. Temperate deciduous forests also experience higher temperatures which results in more vegetation and animal life. Many insects, amphibians, lizards, birds and large herbivores and carnivores make these forests their home. Unit 3 - Ecology 7 / 19

8 Summary of the Temperate Deciduous Forest: Abiotic factors Communities - longer growing season than boreal forest - deciduous trees, many shrubs, and ferns - higher temperature than boreal - many insects and mice forest and tundra - fertile soil - squirrels and many birds - precipitation up to 100 cm/y - black bears, wolves, and deer Unit 3 - Ecology 8 / 19

9 The Grassland Biome The grassland biome is found at approximately the same latitude as deciduous forests. Grasslands receive less moisture than the deciduous forests. This results in too little water to support trees (except near ponds or lakes). The black soil is considered to be the most fertile soil in the world. Grasslands are home to many animals such as snakes, grasshoppers, hawks, mice, and wolves. Grasslands once supported massive herds of migrating bison; however, this migrating pattern is slowly dissipating. Unit 3 - Ecology 9 / 19

10 Summary of Grasslands: Abiotic factors Communities - longer growing season than boreal - fescue grasses forest - higher temperature than boreal - grasshoppers, voles, and mice forest and tundra - rich, fertile soil - snakes and hawks - precipitation from cm/y - bison and wolves Unit 3 - Ecology 10 / 19

11 Assignment pg. 93 Questions: # s 3, 5, 8 Watch: Top 10 Amazing Places On Earth You Won t Believe Are Real Unit 3 - Ecology 11 / 19

12 Climate and Global Warming What is climate? Climate is the average weather conditions in a particular location or region at a particular time of the year. Climate is usually measured over a period of 30 years or more. How does Earth regulate climate? Unit 3 - Ecology 12 / 19

13 The various gases in Earth s atmosphere essentially control Earth s temperature. Specifically, carbon dioxide and water vapour are the two main gases that provide the Earth with insulation. This insulation works similar to how a greenhouse will keep in moisture and heat. Therefore, we called these gases greenhouse gases. Unit 3 - Ecology 13 / 19

14 According to NASA scientists, the planet s temperature ultimately depends on the atmospheric level of carbon dioxide. Global warming is essentially an increase in temperature near the surface of the earth. While such warming has occurred various times throughout Earth s history, it appears to be occurring very quickly today. Such warming is currently attributed to the rising CO 2 levels in the atmosphere. According to NASA s recent study (October 15, 2014) carbon dioxide is responsible for 80% of the radiative forcing that sustains the Earth s greenhouse effect. Unit 3 - Ecology 14 / 19

15 The Effects of Global Warming The most immediate effect of global warming is an increase in global sea level. This is a worldwide concern for human beings. Rises in sea level will not only affect populations that are situated below sea level (the Netherlands, much of California, New Orleans, etc.), but will also alter the naturally occurring cycles (water, carbon, nitrogen, and phosphorus cycles). This alteration will have an unpredictable effect on global climate. Unit 3 - Ecology 15 / 19

16 Various Charts Concerning Global Warming: Figure : Atmospheric CO 2 concentration using ice core proxy data and direct measurements. Source: NASA GISS Watch: Analyzing Ice Cores Unit 3 - Ecology 16 / 19

17 Figure : Global mean land-ocean temperature change. Green bars indicate uncertainty estimates. Source: NASA GISS Unit 3 - Ecology 17 / 19

18 Figure : Calculations of global warming prepared in or before 2001 from a range of climate models. This assumes no action is taken to reduce emissions. Unit 3 - Ecology 18 / 19

19 The Big Question: Is the human species causing or contributing to global warming? If yes, then how are we contributing to global warming? If no, then what is causing this serious spike in atmospheric CO 2 emissions? Watch: Earth s Frozen Regions and Global Warming Watch: Wall-E (Disney...) or Unit 3 - Ecology 19 / 19