2.3 flows of energy and matter notes
1 like9,663 views
The document discusses energy and matter flows within ecosystems. It explains that solar energy enters ecosystems and is lost through reflection and absorption as it passes through the atmosphere. Energy and matter are transferred and transformed as they move through ecosystems, linking different ecosystems together. Key terms discussed include gross primary productivity, net primary productivity, gross secondary productivity, net secondary productivity, carbon and nitrogen cycles, and human impacts on energy and matter flows.
2.3 flows of energy and matter notes
- 1. IB Environmental Systems and Societies p. 1 Topic 2: Ecosystems and Ecology (25 hours) 2.3 Flows of Energy & Matter Significant Ideas: ➔ Ecosystems are linked together by energy and matter flows. ➔ The Sun’s energy drives these flows, and humans are impacting the flows of energy and matter both locally and globally. Knowledge & Understanding: Use these notes to familiarize yourself with ESS terminology and concepts. 2.3.1 As solar radiation (insolation) enters the Earth’s atmosphere, some energy becomes unavailable for ecosystems as this energy is absorbed by inorganic matter or reflected back into the atmosphere. 2.3.2 Pathways of radiation through the atmosphere involve a loss of radiation through reflection and absorption as shown in Figure 4. Original Source: International School of Prague https://sites.google.com/site/environmentalsystemssocieties/home Modified by Brad Kremer, May 2017
- 2. IB Environmental Systems and Societies p. 2 Topic 2: Ecosystems and Ecology (25 hours) 2.3.3 Pathways of energy through an ecosystem include both energy transfers and transformations as shown at the right. See Figure 4 on previous page. 2.3.4 The conversion of energy into biomass for a given period of time is measured as productivity. 2.3.5 Net primary productivity (NPP) is calculated by subtracting respiratory losses (R) from gross primary productivity (GPP). 2.3.6 Gross secondary productivity (GSP) is the total energy or biomass assimilated by consumers and is calculated by subtracting the mass of fecal loss from the mass of food consumed. Original Source: International School of Prague https://sites.google.com/site/environmentalsystemssocieties/home Modified by Brad Kremer, May 2017
- 3. IB Environmental Systems and Societies p. 3 Topic 2: Ecosystems and Ecology (25 hours) 2.3.7 Net secondary productivity (NSP) is calculated by subtracting respiratory losses R from GSP. 2.3.8 Maximum sustainable yields are equivalent to the net primary or net secondary productivity of a system. 2.3.9 Matter also flows through ecosystems linking them together. This flow of matter involves transfers and transformations. Original Source: International School of Prague https://sites.google.com/site/environmentalsystemssocieties/home Modified by Brad Kremer, May 2017
- 4. IB Environmental Systems and Societies p. 4 Topic 2: Ecosystems and Ecology (25 hours) 2.3.10 The carbon and nitrogen cycles are used to illustrate this flow of matter using flow diagrams. These cycles contain storages (sometimes referred to as sinks) and flows, which move matter between storages. 2.3.11 Storages in the carbon cycle include organisms and forests (both organic), or the atmosphere, soils, fossil fuels and oceans (all inorganic). 2.3.12 Flows in the carbon cycle include consumption (feeding), death and decomposition, photosynthesis, respiration, dissolving and fossilization. Original Source: International School of Prague https://sites.google.com/site/environmentalsystemssocieties/home Modified by Brad Kremer, May 2017
- 5. IB Environmental Systems and Societies p. 5 Topic 2: Ecosystems and Ecology (25 hours) 2.3.13 Storages in the nitrogen cycle include organisms (organic), soil, fossil fuels, atmosphere and water bodies (all inorganic). 2.3.14 Flows in the nitrogen cycle include nitrogen fixation by bacteria and lightning, absorption, assimilation, consumption (feeding), excretion, death and decomposition, and denitrification by bacteria in waterlogged soils. 2.3.15 Human activities such as burning fossil fuels, deforestation, urbanization, and agriculture impact energy flows as well as the carbon and nitrogen cycles. Original Source: International School of Prague https://sites.google.com/site/environmentalsystemssocieties/home Modified by Brad Kremer, May 2017
- 6. IB Environmental Systems and Societies p. 6 Topic 2: Ecosystems and Ecology (25 hours) Applications & Skills: Treat the following prompts as assessment questions on your IB ESS exam. Use the terminology and concepts from the notes above to respond to each of these prompts. 2.3.AS1 Analyze quantitative models of flows and energy and matter. 2.3.AS2 Construct a quantitative model of the flows of energy or matter for given data. 2.3.AS3 Analyze the efficiency of energy transfers through a system. Original Source: International School of Prague https://sites.google.com/site/environmentalsystemssocieties/home Modified by Brad Kremer, May 2017
- 7. IB Environmental Systems and Societies p. 7 Topic 2: Ecosystems and Ecology (25 hours) 2.3.AS4 Calculate the values of both GPP and NPP from given data. 2.3.AS5 Calculate the values of both GSP and NSP from given data. 2.3.AS6 Discuss human impacts on energy flows, and on the carbon and nitrogen cycles. Original Source: International School of Prague https://sites.google.com/site/environmentalsystemssocieties/home Modified by Brad Kremer, May 2017
- 8. IB Environmental Systems and Societies p. 8 Topic 2: Ecosystems and Ecology (25 hours) Original Source: International School of Prague https://sites.google.com/site/environmentalsystemssocieties/home Modified by Brad Kremer, May 2017