Presentation on theme: "Chapter 18 G.2 Objectives Ecosystems and Biomass"— Presentation transcript:
1 Chapter 18 G.2 Objectives Ecosystems and Biomass
2 Define Gross Production, Net Production, and Biomass Gross Production – total amount of energy trapped in the organic matter produced by plants per area per time in kilojoules.Net Production – the gross production minus the energy lost through respiration.Biomass – dry weight of an organism measured in g/m²yr
3 Calculate values for gross production and net production using the equation: gross production – respiration = net productionExample:Gross production = 809 kJ / m² yrRespiration = 729 kJ / m² yr809 – 729 = 80Net production = 80 kJ / m² yr
4 Discuss the difficulties of classifying organisms into trophic levels. Many animals such as eagles, coyotes, and lizards are not in just one trophic level because they can be considered as primary consumers, secondary consumers, or tertiary consumers depending on what they eat.Omnivores are also difficult to determine which trophic level because they eat both plants and animals.
5 Explain the small biomass and low numbers of organisms in higher trophic levels Biomass is lost during respiration at each trophic level. When glucose is broken down for energy, it is converted into carbon dioxide gas and water. Carbon dioxide and water are excreted and the biomass of glucose is lost. Each successive level of the ecosystem loses more and more biomass. Energy per gram of food does not decrease, but total biomass of food is less at each trophic level.
7 Distinguish between primary and secondary succession, using an example of each. Primary succession is where plants start growing in a previously lifeless area such as a land that has experiences a volcanic eruption.Secondary succession is when a new organism takes over a upheaval. It is quicker then primary succession. This is because the soil is already in place, a prime example of this is after a forest fire.
8 Outline the changes in species diversity and production during primary succession Fordune stage is the beginning stage where there is nothing present yet.Yellow dune stage is second and can take years, dead organisms piles up to make a new thin layer of soil.Grey dune stage is developed after years of plants dying and decomposing and humus is developed and can hold water.The final stage of the dune sucession is Mature dune, at this point the dune can support a forest.
9 Explain the effects of living organisms on the abiotic environment, with reference to the changes occurring during primary succession.Organic Matter IncreasesResulting from the death and decay of animals and causes the earth to better absorb water, making it able to better support plants.Soil Gets DeeperResults from the mixer of decayed organic matter and abiotic materials (such as sand, rock, etc).Soil Erosion ReducesPlant roots stabilize the abiotic materials (sand, rock, etc) and soil.
10 Explain the effects of living organisms on the abiotic environment, with reference to the changes occurring during primary succession.Soil Structure ImprovesSand and rock don’t hold water, so when soil is produced, it holds water and minerals and allows the anchoring of plant roots.Mineral Recycling IncreasesBacteria and fungus which thrives in such environments recycle the nutrients of dead organisms.
11 Distinguish between biome and biosphere. All the living things that make up our world.BiomeThe division of the biosphere defined by type of vegetation and community structure.
12 Explain how rainfall and temperature affect the distribution of biomes. The effective temperature and rainfall of each biome has a particular range for each biome representing the conditions in each.Two different biomes can have the same temperature or rainfall but usually differ in one or the other.EX. A desert can have the same temperature as a temperate forest but the temperate forest differs by having more rain fall each year causing it to have different flora and fauna than the desert due to having more life sustaining water.
13 Outline the characteristics of six (seven) major biomes. TemperatureMoistureCharacteristics of VegetationDesert60 degrees CelsiusLess than 30cm/YrCacti and shrubs (adaptable to dry)GrasslandCold in winter hot in summerSeasonal drought, medium moisturePrairie grasses (fires prevent invasion)ShrublandMild temperatures in winter, long hot summersRainy winters, dry summersDry woody shrubs that reproduce with fireTemperate deciduous forestVery hot winter very cold winterHigh rainfall, frozen in winterOak, hickory, maple, warm=HerbaceousTropical rainforestVery warmMore than 250cm/YrHigh plant diversity with tree canopyTundraVery cold, layer of permafrost in soil year roundLittle precipitationLichen, mosses, grasses, shrubs, no deep rootsConiferous forestSlightly warmer than tundraSmall amount, but lack of evaporationCone bearing trees