Social exam revision notes : Finals S.2

Deforestation

Permanent removal of trees for land use change (e.g., agriculture, construction).

Most deforestation occurs illegally or due to governmental corruption, often for profit.

Cultivation and Livestock: Farmers often clear forests to create grazing land for cattle, frequently using burning as a method.
Timber Extraction: Large businesses exploit forests for wood products including furniture, homes, and ornaments.
Infrastructure Development: The expansion of cities necessitates the clearance of forests for roads, homes, and shopping centers.
Natural Events: Disasters such as hurricanes can cause significant destruction to large forested areas.

Soil Erosion: Trees play a critical role in holding topsoil in place. When forests are removed, soil washout increases, leading to higher flooding risks and making farmland more challenging to manage.
Climate Change: Trees act as carbon sinks. Their removal leads to increased levels of atmospheric CO2 and reduces the environment’s capacity to absorb carbon.
Habitat Destruction: The loss of trees poses a threat to various animal species, potentially leading to decreased populations or even extinction.
Fragmentation: Construction of roads and other infrastructures divides habitats, which in turn reduces genetic diversity and hunting territories for wildlife.

Afforestation: The process of replanting trees in areas where forests have been cleared. This regeneration can take 20-30 years for effective ecological restoration.
Education: Promoting awareness about the impacts of deforestation among children can guide responsible decision-making in adulthood.
Laws & Regulations: Implementing and enforcing strict laws against deforestation, accompanied by fines and penalties for violations, can deter illegal practices.

The harmful presence of substances in the environment, which can affect aquatic, airborne, or terrestrial ecosystems.

Air Pollution: Affects approximately 100 million people worldwide, posing significant health risks. Emissions result from vehicles and factories, leading to increased cancer risks and shortened lifespans. In China, around 70% of emissions are attributed to transportation.
Water Pollution: Heavy metals and plastics contaminate oceans and rivers, negatively impacting marine life and causing environmental degradation, exemplified by the trash island in the Pacific.
Land Pollution: Results primarily from waste disposal practices that lead to soil contamination.

Marine Wildlife: Plastics and toxic chemicals seriously endanger marine life, with over 1 million birds and 100,000 mammals dying each year due to pollution.

Behavioral Change: Encouraging a critical approach to waste disposal for individuals and businesses can raise awareness and promote responsible waste management practices.
Cleanup Teams: Organizing community initiatives, such as beach cleanups, focuses on physically removing waste from natural environments.
Community Action: Advocating for local bans on factory waste dumping and improving public waste disposal options can help in reducing pollution.
Emission Reductions: Governments may implement strategies like enhancing public transportation systems and transitioning to renewable energy sources to mitigate pollution.

The long-term rise in atmospheric temperatures since the 1800s, predominantly driven by human activities.

Greenhouse Effect: Solar radiation enters the Earth, gets absorbed, and then re-emitted as longwave radiation. Greenhouse gases such as CO2 and methane trap this radiation, causing an increase in atmospheric heat; higher concentrations of these gases exacerbate heat retention.

Sea Level Rise: Melting ice caused by rising temperatures contributes to ocean volume increases, threatening low-lying areas like Bangladesh with flooding.
Extreme Weather Events: Warmer ocean temperatures result in more intense hurricanes and increased evaporation, which leads to both droughts and flooding.

Clean Energy Sources: Transitioning to renewable sources such as solar and hydroelectric power reduces reliance on fossil fuels that emit greenhouse gases.
Government Restrictions: Enacting strict laws to limit emissions is critical; most developed nations have signed agreements to regulate annual emissions.
Carbon Credits: Carbon can be used as currency for businesses, requiring them to purchase or trade for allowances to emit a specified amount of greenhouse gases.

The strategies for handling waste generated by communities, where poor management can result in severe environmental consequences.

An average individual produces approximately 2kg of waste daily, with cities like Bangkok generating about 22 million kg daily.

Leachate Production: Toxic runoff from landfills contaminates soil and can affect food safety.
Methane Emission: Decomposition of waste leads to greenhouse gas emissions.
Health Risks: Poor waste management attracts pests and diseases, presenting health concerns.

Recycle: Promoting the reduce, reuse, recycle approach minimizes overall waste production.
Government Action: Local governments are encouraged to establish appropriate waste management systems for environmentally-friendly disposal methods.

Locations where communities originate and thrive, typically established near abundant natural resources.