Unit 1: Ecology – Sustainable Ecosystems Chapter 2: Understanding Ecosystems 2.1 Life on Planet Earth Habitat: The Spheres of the Earth 1. The _________________ The layer of _____________ surrounding Earth 78% ______________, 21% _____________, 1% ________________________________ Acts like a _______________ by moderating ___________________ - it prevents excessive heating during the day and cooling during the night Blocks some incoming _______________________ (like ______________ that damage our skin) Without the atmosphere, most of Earth’s species _______________________ _______________________________ thick 2. The _________________ Earth’s ___________________________________ Consists of ________________________________ that make up the mountains, ocean floors, and the rest of Earth’s ____________ landscape ______________ km thick 3. The __________________ All of Earth’s _______________________________________________________ Can be _____, ____________, or __________ Earth’s surface 4. The ___________________ The “zone” around earth where _____________________________________________________ _______________ layer 2.2 Introducing Ecosystems Ecosystem Definition: • A large ecosystem (ie: a forest) may contain many small ecosystems (ie: a community of bacteria and fungi living in a rotting log) Composed of: a) ____________ Factors - ________________________________________________________________ - Ex: ___________________ and __________________________ b) _____________ Factors - _______________________________________________ - Ex: , ___________, _________, ____________________, and their ___________________ or ___________________________________ Organism – Individuals of _____________ of species (ex: _________________) Population – all the individuals of a ____________________ in a particular area (ex: ________________________) Community – Individuals from ______________________ in the ecosystem (ex: _____________________________) The ecosystem is _______________________________________________ Sustainable Ecosystems Sustainability: o _____________________change the biotic and abiotic features of an ecosystem, making sustainability difficult. Natural Ecosystems - ____________________________________________________________ Artificial Ecosystems - Ecosystems that are created and maintained by _______________, like a ___________ or a _________________ o Not usually ____________________ o Humans need to maintain their biotic and abiotic features 2.4 Energy Flow in Ecosystems All organisms require __________ to ______________ and ________________. All energy comes from the _________. Types of Energy: 1. ___________ Energy – energy ___________ from the _______ 2. ___________ Energy – _________ forms of __________ energy 3. ___________ Energy – energy transferred through _____________ and _____________ -- what __________ the atmosphere, ______________ water, and ____________ winds 4. ___________ Energy – can be ________ in cells and _____________ when needed -- used by all organisms to perform functions like ____________, __________, and _________________ Distribution of Incoming Solar Radiation Photosynthesis - Process where organisms ________________________________________________________ - Without it, most life on Earth _________________________________ - Requires _____________________ (can only be done __________________________) - Mostly done by ________________________ - Green colour comes from_______________, a chemical that captures light energy Word Equation: Chemical Equation: - The _________ that is formed contains _________________________________ - Plants __________ this energy in their ______, _______, ________, and _________ - Done by _________________________________________ o Organisms that __________________________________________________________ o Examples: __________________________________________________ Cellular Respiration - The “________________” of photosynthesis - A chemical reaction where ______________________________________________ to provide _________ for the cell - Can be done during __________________________________ Word Equation: Chemical Equation: - Done by all organisms: both __________________________ and ________________________ - Consumers: • Organisms that obtain energy by ___________________________________ • _________________ make their own food • Without ____________________, consumers could not survive! • Examples: _________________________________________ 2.5 Food Webs and Ecological Pyramids Types of Consumers Herbivore – animal that eats _______________________________________ Carnivore – animal that eats _______________________________________ Top Carnivore - __________________________________________ Omnivore – animal that eats _______________________________________ Scavenger – animal that ___________________________________________________ Insectivore - _______________________________________________________ ________________________________________________________ Decomposer - ______________________________________________________ Ecological Niche - The role of a __________ within its ______________, including ________________, ________________, and __________________ - No _____________________ occupy identical niches Food Chain illustrates _____________________________ in an ecosystem - how _________________________________ from one organism to another - A sequence of organisms, each feeding on the next. For example, Trophic Level – levels that describe the __________________ of an organism along a food chain Food Web - Show a series of _______________________________________ More complex webs are more _________ than simple ones because: What would happen to this food web if all the weasels died from some disease? Energy Pyramids - Show relationships between _____________________ in ecosystems - As you go ________ trophic levels, the amount of energy available ________________ o This is because organisms can’t ______________________________________. Some is released as ___________________________. - Species in high trophic levels often have __________ energy available to them than species near the bottom o Therefore, their populations are _______________ o Only _______ of energy from the lower trophic level is passed on to the next level 2.6: Cycling of Matter in Ecosystems • Matter cannot be __________________________________________ – substances (like water, carbon, and nitrogen) are continuously consumed, rearranged, stored, and used on earth. The Water Cycle 1. Liquid water ___________________, forming water ___________ that moves through the atmosphere. 2. The vapour eventually ________________, forming ___________________________, and 3. falls to Earth as _____________________. 4. __________________________may enter the soil, groundwater, or bodies of water 5. Water taken in by plant roots may be released from leaves by __________________________ 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. transpiration The Carbon Cycle • Carbon is cycled through the 4 spheres, mostly through __________________________________ __________________________________________ • Most of Earth’s carbon is ___________________ – it is ____________ in deposits, like fossil fuels, coal, oil, natural gas, and limestone. • A large amount of carbon is also stored in ____________________ and as _____________________________ in the oceans 1. Photosynthesis uses ________________________________ 2. Plants and animals release CO2 into atmosphere through ________________________________ 3. Dead plants and animals are broken down by ___________________ - carbon enters the ground. 4. _________________________ occurs over time, into deposits 5. _________________________ occurs as deposits get burned. CO2 enters the atmosphere. 6. and 7. Carbon is stored as _____________________ formed from ________________________ _______________________ (shells of crustaceans) 8. Limestone releases carbon dioxide into the atmosphere when it reacts with ___________________ _______________________________ are affecting the carbon cycle. • By __________________________________, we are releasing large amounts of CO2 into the atmosphere. • This raises global temperatures, which melts ice caps, which causes sea levels to rise, which disrupts ecosystems. • _________________________________ is increasing the amount of CO2 in the atmosphere (because there are ______________________________!) The Nitrogen Cycle • The atmosphere is about 78% nitrogen, but it is difficult to extract from the air_________________ for use by plants and other organisms 1. ______________________________________ occurs when nitrogen is converted to other compounds like nitrates, nitrites, and ammonia. This happens in 2 ways: a. By ___________________________________________ in the soil b. By ___________________ 2. ______________________________________ are now available to producers in the soil 3. ________________________ the nitrogen which gets _______________________ the food chain 4. Excess nitrogen is ____________________ as waste and goes back into the soil 5. _________________________ of dead organisms sends nitrogen back into the soil 6. __________________________ can also occur – the opposite of nitrogen fixation. Denitrifying bacteria will break down nitrates and release nitrogen back into the atmosphere 2.7 Biotic and Abiotic Influences on Ecosystems Limiting Factor • Any factor that _______________________________________________________ • May be biotic or abiotic • __________________________________ are usually limiting factors Carrying Capacity • the ________________________________________ of a species that an ecosystem can sustain • a population can only get so large until it _____________________________________ Abiotic Limiting Factors • Determine ____________________________________________________ • Limiting Factors in _________________________ Ecosystems • Limiting Factors In ______________________ Ecosystems • What human actions are altering these abiotic factors? Biotic Limiting Factors • Determine a ___________________________________ • Involve different interactions between individuals: • Competition – • Predation – • Symbiosis – • Mutualism – • Parasitism – • Commensalism – 2.8 Major Terrestrial Biomes Biome • Canada’s Biomes • Canada has __________ major biomes o Growing Season Temperature Soil Precipitation Types of Producers Types of Wildlife British Columbia contains many smaller biomes, including the _______________________ 2.9: Major Aquatic Ecosystems Aquatic ecosystems are classified as either ____________________________ (salt concentration less than 1%) or _______________________________ (salt concentration of about 3%) 1. Freshwater Freshwater ecosystems contain _________________ and _______________ which feed fresh rainwater to meltwater into ponds or lakes. The nutrient levels of these water bodies greatly influences the ____________ and _______________ of organisms found in them. In oligotrophic lakes, the water is _____________ because of the __________ nutrient levels. In eutrophic lakes, the water is ________________ because of the ___________ nutrient levels and the growth of ____________________________________________________. The area of land through which water drains into a single river or lake is called a _________________. 2. Marine Much of the ocean supports __________________________ life. The __________________ and ___________________ do not support life, but _________________________________________ are nutrient rich and do support life. 3 types of areas that are nutrient rich and support life are: _____________________________ ____________________________________________________________________________ The ___________________ zone, the area between low tide and high tide, experiences a wide _______________ of environmental condition. Organisms living there must be able to survive these ____________________ condition as well as the constant ______________________ of the waves. To withstand this, most species have ___________________________________________ and _____________________________ 3.3 The Importance of Biodiversity Biodiversity – Species Richness – Many species are dying out and becoming _______________ Their habitats are being destroyed at a _________________________ due to ______________________________ like: Species at Risk in Canada Classification Definition Examples in Canada 3.5: The Introduction of Non-Native Species Non-Native Species • Are introduced either: a) ____________________ – ie: attached to a boat b) ____________________ – ie: to control another population • Their introduction _____________________ because few species can tolerate a new environment. • Sometimes, they are __________________ and can ____________________________________ Invasive Species • A non-native species whose ______________________ or __________________________ introduction _________________________________________ the natural environment • ______________________________native species for resources • There are over _________ in Canada Impacts of Invasive Species 1. • Invasive species _____________________ or _______________ native species, resulting in population decline or extinction. • Change ecosystem dynamics by _______________________________ or __________________ • They can _______________________________________, leading to financial loses. • Species loss has negative effects on __________________________________ • Reduced water quality has impacts on _______________________________________________ • _______________________________ organisms are introduced, like West Nile virus. • _________________________ need to be used to control invasive species population, affecting 2. 3. 4. health and causing pollution. Controlling Introduced Species 1. • _______________________ are used on forest and agricultural pests. • May also ___________________________________________ and pollute the air, water, and soil. • We can put up ________________________ or _________________________ invasive species 2. by hunting, trapping, and cutting down or burning plants. 3. • _____________________________________ that control the invasive species. 4.2: Managing the Soil Soil Soil is one of earth’s _________________________________________ and is critical to our survival • ___________ depend on soil for ___________________________________________ • ___________ depend on soil for ___________________________________________ Soil is more than just dirt! • It is a ________________ of minerals, water, dissolved nutrients, air, and decomposing matter • It is _________________ to organisms, from microscopic bacteria to large burrowing mammals Managing Soil Nutrients • The most important nutrients for plants are ____________________________________________ • How do we replace these nutrients? Use ___________________________ • There are two types of fertilizers: Natural Fertilizers Definition Examples Pros Cons Synthetic Fertilizers Environmental Impacts of Synthetic Fertilizers 1. Nutrients are __________________________________ in synthetic fertilizers • Nutrients enter the soil rapidly and _______________ the soil organisms. • Soil then has less _____________________________________________ • Soil becomes _________________________ on synthetic fertilizers. • Soil is more likely to ____________________. 2. Leaching • Occurs when _______________________________ from the soil as_________ passes through it. • _____________________________ (which we drink) becomes _________________________ with nitrogen, causing health problems. • Increases the ________________________________ in aquatic ecosystems, which decreases the level of _____________________ in the water, killing fish and other organisms. 4.4 & 4.5: Pests, Poisons and Pesticides Pests • Organisms that might ___________________________ or _________________ crop species • i.e: _____________________________________________ Pesticide • A substance used to ______________________________. • May be toxic to a ____________________ of species, or to a __________________________ of species. • Cause ____________________ or _______________________ harm to the pest • Can help farmers __________________________________ or ___________________________ of biting insects that spread diseases, like mosquitoes. • Can also have many negative effects Issues with Pesticides 1. Applied by aerosol (__________________________) • Some pesticide _____________________________________ because it’s carried away by the ________, causing _________________________. 2. Kill species they were not intending to kill 3. Pesticide Resistance • Over time, pests can become ____________________ to pesticides. Farmers have to apply _________________________ of this pesticide, or _________________ to a different pesticide. Pesticides gone wrong: DDT 1. DDT is a pesticide that was used in Borneo in the 1950s to ______________________________________________________________. 2. It also _________________________, so they were not able to prey on the thatch-eating ________________________. These caterpillars caused _________________ to villager’s homes. 3. DDT also ___________________________________ that were then consumed by ____________. The DDT damaged the nervous system of the lizards. _______ ate the lizards and were also poisoned. 4. When the cats disappeared, the __________ population in the village increased dramatically. 5. The ____________ on the rats carried the _____________ – having more rats meant that the plague spread faster. 6. To prevent an epidemic, a large number of _______________________ had to be introduced to control the rats. Bioaccumulation • Happens when an organism _________________________________________ • Pesticide _________________ in their body and cannot be easily ____________________ Bioamplification • As larger organisms consume the infected organisms, the toxins are _____________________ and ____________________ the food chain. The higher up on the food chain, the _______________________________________ the pesticide becomes. • This is what happened with DDT, which greatly affected many species of ____________________