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Ecology and Earth Science - Sustainable Development Goals (SDGs)

Grade 7IB

Review the key concepts, formulae, and examples before starting your quiz.

🔑Concepts

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Sustainable Development: Development that meets the needs of the present without compromising the ability of future generations to meet their own needs, focusing on three pillars: Economic, Social, and Environmental.

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The 17 SDGs: A universal call to action by the UN to end poverty and protect the planet. Key ecological goals include Goal 13 (Climate Action), Goal 14 (Life Below Water), and Goal 15 (Life on Land).

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Carbon Footprint: The total amount of greenhouse gases, primarily CO2CO_2 and CH4CH_4, produced by human activities, measured in units of CO2CO_2 equivalent (CO2eCO_2e).

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Ocean Acidification: The decrease in the pHpH of the Earth's oceans caused by the uptake of carbon dioxide (CO2CO_2) from the atmosphere, which reacts to form carbonic acid (H2CO3H_2CO_3).

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Biodiversity: The variety of life in a particular habitat or ecosystem. High biodiversity is crucial for ecosystem resilience and is a core focus of Goal 15.

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Renewable vs. Non-renewable Resources: Goal 7 (Affordable and Clean Energy) emphasizes transitioning from fossil fuels to renewable sources like solar, wind, and hydroelectric power to reduce CO2CO_2 emissions.

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Photosynthesis and Carbon Sequestration: The process by which plants convert 6CO26CO_2 and 6H2O6H_2O into glucose (C6H12O6C_6H_{12}O_6) and oxygen (O2O_2), acting as a natural carbon sink.

📐Formulae

6CO2+6H2O+light energy→C6H12O6+6O26CO_2 + 6H_2O + \text{light energy} \rightarrow C_6H_{12}O_6 + 6O_2

CO2+H2O→H2CO3→H++HCO3−CO_2 + H_2O \rightarrow H_2CO_3 \rightarrow H^+ + HCO_3^-

pH=−log⁡10[H+]pH = -\log_{10}[H^+]

Ecological Footprint=Total Resource ConsumptionBiocapacity per Hectare\text{Ecological Footprint} = \frac{\text{Total Resource Consumption}}{\text{Biocapacity per Hectare}}

💡Examples

Problem 1:

A forest area absorbs approximately 1212 tonnes of CO2CO_2 per hectare per year. If a small city produces 12001200 tonnes of CO2CO_2 annually, how many hectares of forest are needed to neutralize its carbon output (Goal 15 - Life on Land)?

Solution:

1200 tonnes12 tonnes/hectare=100 hectares\frac{1200\text{ tonnes}}{12\text{ tonnes/hectare}} = 100\text{ hectares}

Explanation:

To achieve carbon neutrality, the rate of carbon sequestration by the forest must equal the rate of carbon emission by the city. This aligns with SDG 13 (Climate Action).

Problem 2:

Explain how the reaction CO2+H2O→H2CO3CO_2 + H_2O \rightarrow H_2CO_3 affects marine life with calcium carbonate shells (CaCO3CaCO_3).

Solution:

The formation of H2CO3H_2CO_3 (carbonic acid) increases the concentration of H+H^+ ions, lowering the pHpH of the water. This acidity reacts with CaCO3CaCO_3 in shells, causing them to dissolve or making it harder for organisms like coral to build them.

Explanation:

This demonstrates the chemical impact of atmospheric pollution on SDG 14 (Life Below Water).