Ecology. Introduction to Ecology

Transcription

1 Ecology Introduction to Ecology

2 A. Defining Ecology 1. Ecology Naturalscience of how nature works together. a. Concerned with cycles of materials. b. Looks at how organisms interactwith each other and their environment. c. Views human kind as partof the environment.

3 A. Defining Ecology 2. Environmental Science The effectof humans on the natural world. a. A mix of naturalscience and socialscience. b. More political than ecology. c. Looks at man as an outside force.

4 B. Structure of Nature 1. Environment Everythingthat an organism can interact with a. Biotic factors Livingthings; Plants, animals, insects, etc. b. Abioticfactors Nonlivingparts; Water, sunshine, minerals, climate temperature, rainfall, seasons.

5 B. Structure of Nature 2. Biosphere The partsof the Earth where life can happen. a. Extends from about 4 miles below the ocean to about 4 miles up. b. As we exploreregions more, we expandthe range.

6 B. Structure of Nature 3. Ecosystem The interconnected relationships between the differentparts of the environment. a. Often refers to the lifeof an area. b. Can have many different sets of conditions.

7 B. Structure of Nature 4. Biome Part of an ecosystem with specific conditions. a. Conditions are mostly dependent on the climate. Avg. temperature, Annual rainfall, etc. b. Conditions determine the kinds of plants and animals. c. An ecosystemcan have several biomes.

8 B. Structure of Nature 5. Habitat Part of the ecosystemwhere an organism lives. a. Some organisms are specific to a small part of a biome. b. Some organism s habitatcan cross several biomes.

9 B. Structure of Nature 6. Niche The rolean organism plays in an ecosystem. a. Ex. What it eats, What it provides, Predator/Prey. b. An organisms nichemay change during its life. 7. Biodiversity Different types of organisms in an ecosystem.

10 C. Types of Biomes 1. Forests a. Tropical Rainforests (1) Wettestclimate on Earth. (> 100 in. of rain) (2) Most diversebiome (3) Found in the lowlandsnear the equator

11 C. Types of Biomes 1. Forests b. Temperate Rainforest (1) Pine forests of Pacific Northwest (2) Not quite as wetas tropical. (3) Usually found along the coast.

12 C. Types of Biomes 1. Forests c. Deciduous Forest (1) Typical biome of Western PA. (2) Gets inches of rain per year. (3) Trees changewith the seasons. (4) Deciduous trees lose their leaves.

13 C. Types of Biomes 1. Forests d. Boreal forest (Tiaga) (1) Found just belowthe Arctic Circle. (2) Gets inches of precipitation per year. (3) Pine trees can survive the cold and snow better than deciduous trees.

14 C. Types of Biomes 2. Chaparral a. Climate found along coast in warm latitudes. b inches of rain, but only during the wet season. c. Plants and animals must be able to endure long droughts.

15 C. Types of Biomes 3. Grasslands a. Usually very flat, fertile lands. b. Gets between in. of rain per year. c. Different types of grasslands based on temperature. d. Ex. Prairie(U.S.), Savanna(Africa), Steppes (Central Asia), Pampas(South America)

16 C. Types of Biomes 4. Desert and Tundra a. Driestand least diverse biomes on Earth. b. Gets less than 10 in. of rain per year. c. Desertsoccur in many climates. d. Tundra occur above the Arctic Circle.

17 C. Types of Biomes 5. Rivers a. Biome that can change drastically from beginning to end. b. Moves fasthigh in the mountains, slow when it reaches its end. c. Changing conditions, changes the kind of life we find.

18 C. Types of Biomes 6. Lake a. Abundanceof life changes with depth. b. Most of the lifeis close to shore. c. Biglakes have similar characteristicsto the ocean.

19 C. Types of Biomes 7. Ponds a. Smallerand more shallowthan lakes. b. Diverseecosystem due to good supply of nutrients. c. Because water is limitedand doesn t circulate, it is very susceptible to pollution.

20 C. Types of Biomes 8. Wetlands a. Hard to definebecause they come in so many forms. b. Must have standingwater at least part of the year. c. Ex. Swamps, marshes, bogs, moors

21 C. Types of Biomes d. Very important ecosystem. (1) Birdsrely on the food supply. (2) Fishuse the calm waters for spawning. (3) Slow moving water is cleanedby the soil. (4) Provides an overflowarea that reduces flooding.

22 C. Types of Biomes 9. Estuary a. Place where a rivermeets the ocean. b. Mix of saltand freshwater. c. Diverseecosystem, with many types of fish, as well as lots of shellfish. d. In dangerfrom pollution. e. Many large citiesare built near estuaries.

23 C. Types of Biomes 10. Coral Reef a. Shallowocean environment along the coasts of tropical islands. b. Most diverse aquatic ecosystem. c. Very sensitive to changes in conditions. d. The coralis a living organism, but only on the outer edges.

24 C. Types of Biomes 11. Ocean a. Most of life is near the shore. b. Only ecosystem to not rely on plantsfor photosynthesis. c. In the deep waters, small organisms, called plankton, do the photosynthesis.

25 C. Types of Biomes 12. Polar Region a. Area of frozen oceanand glaciernear the poles. b. Even though much of the life is land-based, it is considered an aquatic ecosystem. c. The food chainrelies on the ocean.

26 A. Many environmentalists believe that the root of all environmental problems is overpopulation. 1. The current population of the Earth is over 7 billion. 2. It took until 1800 for human population to reach 1 billion. 3. By 1930, the population reached 2 billion.

27 4. Environmentalists believe that we have exceeded the Earth s carrying capacity. a. Carrying capacity is the maximum population that an area can support. (1) Depends on the available resources. (2) Resources are anything that the organism needs to survive. (3) Examples would be food, water, shelter and other sources of energy.

28 b. Some groups claim that Earth s carrying capacity is significantly lower than today s population. (1) One statistic said that the US needs to reduce the population by one third and the world population by two thirds. (2) Others believe that we need to slow the growth rate before we exceed capacity.

29 c. Environmental groups want humans to be at a zero-sum gain in population. (1) This means for every baby born, a person dies. (2) They have suggested putting limitson the number of children. (3) Other more radical actions have been suggested.

30 5. Over population leadsto many of the problems we face today. a. We need to clear habitats for homes and farmlands. b. Increased human activities leads to pollution of air and water. c. Need for foodhas lead to farming techniques that are not necessarily good for the environment.

31 B. Air Pollution 1. Pollution increases rapidly with industrial activities. a. Burning coaland oilproduces carbon dioxide, sulfur dioxide, nitrogen oxides. (1) Many of these gases produce acid rain. (2) We burn these fuels in steel manufacturing, generated electricity, etc.

32 b. Driving cars also produces carbon dioxide. (1) Carbon dioxide creates the greenhouse effect. (a) The gases hold in heat. (b) It is believed that the greenhouse effect will lead to global climate change. (2) Climate change could lead to many other environmental issues.

33 2. Certain chemicals, called CFC s, are damaging the ozone layer. a. Ozone is a molecule of oxygen with three atoms. (1) High in the atmosphere these molecules gather into a layer. (2) The ozone layer protects use from harmful Ultraviolet (UV) rays.

34 b. CFC s, used in aerosol cans and refrigeration, have caused a thinning in the ozone layer. c. Increased UV rays can have a serious affect on many organisms. d. This will greatly affect food webs.

35 c. Air pollution is not limited to our atmosphere. 1. Burning fuels can increase the level of ozone at ground level. (a) When air is stagnant, the level of ozone can make it difficult for some people to breathe.

36 2. Air pollution can occur indoors. (a) Second-hand smoke can create a problem for non-smokers. (b) Carbon monoxidefrom the furnace can create a poisonous atmosphere. (c) Vapors from cleaning supplies and paint products can be overwhelming without proper ventilation.

37 C. Water Pollution 1. Water pollution comes in three types: Residential, Agricultural and Industrial. a. Residential includes lawn carechemicals, sewage, motor oil. b. Agricultural pollution includes pesticides, weed-killers, and fertilizer.

38 c. Industrial pollutants come from the dischargefrom factories, air pollutants that fall into the water and abandoned mine drainage. (1) Fracking, or hydraulic fracturing, involved in natural gas drilling is an industrial pollution. (2) This is main issue in the Marcellus Shale debate.

39 2. Water pollution will affect aquatic food webs. 3. It spreads outbecause water systems are interconnected. 4. It also affects the availability of clean drinking water. 5. It contributes to water shortages. 6. It often leads to deaths in poor areas of the world due to parasites and diseases.

40 D. Habitat Loss 1. Increased population means an increased need for land. a. Humans need land for homes and farms. b. This need leads to the destruction of forests and wetlands.

41 2. Deforestation is the clearing of large forest areas. a. It happened in North America during colonial times, during the expansionof America and into the early 20 th century. b. Today, we see it happening in rainforest areas, like Africa, South America and Southeast Asia.

42 3. Wetlands destruction is more of a 20 th century problem. a. Most common wetland areas in the US are Florida, Atlantic seaboard, and Gulf Coast. b. Wetlands are usually very level and occur in warm climates, which make them valuable as real estate.

43 4. Problems of deforestation and wetland destruction. a. Loss of biodiversity many organisms will lose population or go extinct. b. Increased greenhouse effect the plant life in these habitats absorb carbon dioxide. c. Wetlands as a natural filter, cleaning the water, and prevent flooding.

44 E. Energy Usage 1. Our most common sources of energy are coal, oil, and natural gas. a. Classified as fossil fuels, because they form from dead organisms. b. Process takes millions of years. c. They are considered nonrenewable. (1) Once we use them, they are gone forever. (2) They will eventually run out.

45 2. Acquiring enoughof these resources is becoming increasingly difficult. a. Resources in some areas are running low. b. Increased populationhas increased demand. c. New methods of drilling or mining are controversial.

46 (1) Mining for coal underground is very dangerous, but strip mining digging down to the coal destroys the environment. (2) Drilling for Marcellus Shalecan ruin water supplies. (3) Off-shore drilling drilling in shallow areas of the ocean can destroy very fragile ecosystems. 3. Burning fossil fuels creates pollution, particularly the greenhouse gas, carbon dioxide.

47 4. Renewableresources are those that naturally replenishthemselves or will not run out. a. Ex. Wind, Hydoelectric, Solar, Geothermal b. Advantages: The energy source is free, little or no pollution. c. Disadvantages: Take up a lot of space, not very efficient with current technology

48 F. Biodiversity 1. Mass Extinction The loss of a significant number of species from the Earth. a. Chief cause is lossof habitat. b. Invasive species speciesin an area that they are not native kill many nativespecies. (1) These species do not have natural enemies. (2) Native species may not viewthem as a threat. (3) Enter an ecosystem through accidentalor purposefulaction of humans.

49 c. US enacted the Endangered Species Act to protect species from extinction. (1) Restrictsactivities that can impact species that are endangered or threatened. (2) Affects both civilianand government projects.

50 2. Animal Rights vs. Animal Welfare a. Animal Welfare Humans have the responsibility to not cause any undo suffering to animals. (1) Animals can be used, but only if they are cared for properly. (2) If done properly farming, the dairy industry and raising animals for foodis acceptable.

51 b. Animal Rights Animals should be allowed to live their lives without human interference. (1) Animals have the same rights usually only granted to people. (2) Goes far beyond animal welfare.

52 c. Common battle grounds (1) Animal testing Testing medicines and cosmetics. (2) Factory farms Large-scalefacilities that keep animals in small areas to maximizethe number of animals they can raise.

53 d. Animals are friends not food. (1) Ovalactalvegetarians do not eat meat, but will eat eggsand dairy productsthat come from animals. (2) Strictvegetarians do not eat anyfood that comes from an animal. (3) Vegans do not eat or use any product that comes from an animal.