environmental management

3 Managing Human Population

Human Population Dynamics and Structure

• Population density is calculated by dividing the number of individuals by the area they occupy, providing insights into resource distribution.

• Factors influencing population density include environmental conditions, economic opportunities, and social structures.

• Understanding age composition is crucial for predicting future population trends and resource needs.

• Changes in birth, death, and migration rates directly affect population dynamics and structure.

• The dependency ratio is a key metric, calculated as: (young + old) / working-age population × 100, indicating economic burden.

• Differences in population structures between High-Income Countries (HICs) and Low-Income Countries (LICs) highlight varying developmental challenges.

Impacts of Human Population Change

• Ageing populations can lead to lower tax revenues and increased healthcare costs, straining public resources.

• The pressure to raise retirement ages and adapt social services to accommodate an older demographic.

• Economic implications of population changes, including labor market shifts and resource allocation.

• Social impacts, such as changes in family structures and community dynamics due to population shifts.

• Historical context: How past population booms and declines have shaped current societal structures.

• Case studies illustrating the impacts of population changes in different countries, focusing on both HICs and LICs.

Strategies for Managing Population Change

• Effective strategies include improving access to contraception and education, particularly for women, to manage birth rates.

• The role of health care improvements in reducing mortality rates and managing population growth.

• Local, national, and global policies, including pronatalist and antinatalist strategies, can influence population dynamics.

• The significance of international agreements, such as the UN Agenda 21, in addressing global population challenges.

• Evaluating the effectiveness of various strategies through case studies from different countries.

• The importance of community engagement and education in implementing population management strategies.

4 Managing Ecosystems and Biodiversity

Understanding Ecosystems

• Major terrestrial biomes include deserts, forests, grasslands, and tundras, each with distinct climates and vegetation.

• Primary and secondary succession processes illustrate how ecosystems develop and change over time.

• Gross primary productivity (GPP) and net primary productivity (NPP) are key concepts in understanding ecosystem productivity.

• Energy transfer efficiency between trophic levels is crucial for ecosystem health and sustainability.

• Ecological pyramids visually represent the distribution of numbers, biomass, and energy within an ecosystem.

• The shapes of ecological pyramids can indicate the health and stability of ecosystems, with inverted pyramids signaling potential issues.

Conservation of Biodiversity

• Native species are those that naturally occur in an ecosystem, while invasive species can disrupt local biodiversity.

• The impacts of invasive species include competition with native species, altering habitats, and introducing diseases.

• Conserving biodiversity is essential for maintaining ecosystem services, such as pollination, water purification, and climate regulation.

• The potential for discovering new medicines and resources from diverse species highlights the importance of biodiversity.

• Cultural and recreational values of biodiversity contribute to human well-being and quality of life.

• Case studies demonstrating successful biodiversity conservation efforts and their outcomes.

4.2 Managing the Conservation of Biodiversity

Legislation and Protocols for Biodiversity Conservation

• Key international agreements include CITES, which regulates trade in endangered species, and the IWC, which focuses on whale conservation.

• The EU CFP aims to ensure sustainable fishing practices, while the ITTO promotes sustainable timber trade.

• The IUCN Red List provides a comprehensive inventory of the global conservation status of biological species, helping prioritize conservation efforts.

EDGE Programme and Its Role

• It aims to raise awareness and provide funding for the conservation of these unique species, which often lack attention compared to more charismatic animals.

• Examples of EDGE species include the Saola and the Yangtze Giant Softshell Turtle, both critically endangered.

• The programme emphasizes the importance of genetic diversity in conservation efforts.

Captive Breeding and Release Strategies

• Successful examples include the California Condor and the Arabian Oryx, both of which have been reintroduced into the wild.

• Challenges include ensuring genetic diversity and adapting animals to their natural habitats post-release.

• Ethical considerations arise regarding the welfare of animals in captivity and the potential for domestication.

Habitat Conservation and Creation

• Strategies include establishing protected areas, nature reserves, and conservation zones to safeguard ecosystems.

• Rewilding is a modern approach that aims to restore ecosystems by reintroducing native species and allowing natural processes to occur.

• The effectiveness of habitat creation, such as artificial wetlands, in supporting biodiversity is an ongoing area of research.

4.3 Impacts of Human Activity on Ecosystems

Human Impacts on Tropical Rainforests

• Fuel wood collection and timber extraction contribute to ecosystem degradation.

• Climate change exacerbates the impacts of human activity, altering rainfall patterns and increasing temperatures.

• Strategies for managing these impacts include sustainable harvesting and the establishment of protected areas.

Human Impacts on Antarctica

• Ozone depletion has increased UV radiation, impacting both terrestrial and marine ecosystems.

• Tourism poses risks of pollution and disturbance to wildlife, necessitating strict regulations.

• The Antarctic Treaty of 1959 is a key international agreement aimed at preserving the continent for peaceful and scientific purposes.

Management Strategies for Human Impacts

• Prohibited activities, such as mineral extraction, help protect fragile ecosystems.

• Waste management and tourism control are essential for minimizing human footprints in sensitive areas.

• International cooperation is crucial for addressing transboundary environmental issues.

5 Managing Resources

Food Security

• Causes of food insecurity include population growth, climate change, and agricultural diseases.

• Impacts of food insecurity can lead to malnutrition, forced migration, and conflict.

• Strategies to manage food security include improving agricultural techniques and reducing food waste.

Energy Resources

• Energy security refers to the reliable availability of energy sources at affordable prices.

• Causes of energy insecurity include fossil fuel depletion and climate change.

• Strategies for managing energy security involve increasing energy efficiency and investing in renewable resources.

Waste Management

• Impacts of waste disposal can lead to soil contamination, greenhouse gas emissions, and health risks.

• Strategies to reduce waste impacts include promoting recycling, composting, and using biodegradable materials.

• Education and financial incentives can encourage sustainable waste management practices.

6 Managing Water Supplies

Challenges in Water Management

• Causes of water insecurity include climate change, population growth, and pollution.

• Effective management strategies must consider both supply and demand factors.

• Integrated water resource management (IWRM) is a holistic approach to managing water resources sustainably.

6.1 Global Water Distribution

Distribution of Earth’s Water

• The Earth's water is primarily salt water, constituting about 97.5% of total water, found in oceans.

• Surface fresh water includes ice sheets, glaciers, lakes, rivers, swamps, marshes, and permafrost, which account for approximately 2.5% of total water.

• Sub-surface fresh water consists of soil moisture and groundwater, with significant reserves stored in aquifers.

• Atmospheric water, although a small fraction, plays a crucial role in weather patterns and climate.

• Understanding the distribution is essential for managing water resources effectively, especially in water-scarce regions.

Water Security

• Water security is defined as the ability to access sufficient quantities of clean water for food production, sanitation, and health care.

• It is influenced by various factors including climate change, population growth, and land use changes.

• The disparity in water availability between regions leads to significant inequalities, impacting socio-economic development.

• Effective water management strategies are essential to ensure water security, particularly in developing countries.

• International cooperation and agreements can enhance water security by addressing transboundary water issues.

Causes of Water Insecurity

• Climate change leads to altered rainfall patterns, increasing the frequency of droughts and floods.

• Pollution events from industrial activities contaminate water sources, exacerbating water scarcity.

• Inadequate sanitation facilities contribute to waterborne diseases, further straining water resources.

• Population growth increases demand for water, leading to over-extraction and depletion of water sources.

• Mismanagement of irrigation practices, such as salinization, reduces agricultural productivity and water quality.

Impacts of Water Insecurity

• Water insecurity results in reduced crop yields, leading to food shortages and malnutrition.

• Livestock death due to lack of water affects food supply chains and rural economies.

• Contaminated drinking water causes illnesses, including diarrhoea and cholera, impacting public health.

• Economic impacts include increased costs for water treatment and healthcare, straining national budgets.

• Social unrest can arise from competition over scarce water resources, leading to conflicts.

Strategies for Managing Water Security

• Sustainable water extraction methods include the use of aquifers, boreholes, and gravity-fed schemes to improve supply.

• Reducing water usage through improved irrigation techniques and rainwater harvesting can enhance efficiency.

• Education on sustainable water use practices is vital for community engagement and awareness.

• International agreements and aid can support water management initiatives in vulnerable regions.

• Rationing and conservation measures can help manage demand during periods of scarcity.

7 Managing the Atmosphere

Acid Deposition

• Acid deposition refers to the deposition of acidic pollutants from the atmosphere, occurring as wet (rain, snow) or dry (dust, gases) deposition.

• The formation involves the combustion of fossil fuels, releasing sulfur dioxide and nitrogen oxides, which react to form sulfuric and nitric acids.

• Impacts include harm to aquatic environments, vegetation, and the deterioration of buildings.

• Fish populations are particularly vulnerable due to gill damage from acidified waters.

• Agricultural crops experience reduced yields and defoliation due to acid exposure.

Photochemical Smog

• Photochemical smog is a mixture of air pollutants formed when nitrogen oxides and volatile organic compounds react in sunlight, producing ground-level ozone.

• It leads to health issues such as eye and respiratory irritation, and negatively impacts crop yields.

• The presence of smog can also deteriorate materials like plastics and rubber, leading to economic losses.

• Urban areas are particularly susceptible due to high traffic and industrial emissions.

Managing Air Pollution

• Strategies for managing air pollution include reducing fossil fuel use and implementing emissions controls such as catalytic converters and electrostatic precipitators.

• Legislation at local, national, and international levels can enforce pollution reduction measures.

• The 'polluter pays' principle encourages industries to take responsibility for their emissions.

• Public awareness campaigns can promote sustainable practices and reduce individual carbon footprints.

• Urban planning can restrict vehicle use in densely populated areas to improve air quality.

Ozone Depletion

• Ozone depletion occurs when chlorofluorocarbons (CFCs) break down in the stratosphere, releasing chlorine atoms that destroy ozone molecules.

• The ozone hole is defined as areas with ozone concentrations below 100 Dobson Units, primarily observed over Antarctica.

• Increased UV radiation due to ozone depletion leads to health issues like skin cancer and cataracts, as well as impacts on biodiversity.

• International agreements have aimed to phase out ozone-depleting substances, although some alternatives still pose risks.

• The Rowland-Molina hypothesis illustrates the importance of experimental evidence in understanding ozone depletion.

8 Managing Climate Change

Climate Change Overview

• Greenhouse gases, such as carbon dioxide, methane, and water vapor, trap infrared radiation, leading to the enhanced greenhouse effect.

• Major sources of emissions include fossil fuel combustion, agriculture (methane from livestock), and waste management (landfills).

• Monitoring climate change is challenging due to limited historical data and the complexity of climate models.

• Feedback mechanisms complicate predictions, as the relationship between cause and effect can be delayed.

• Scientific consensus varies due to uncertainties in data interpretation and political implications.

Impacts of Climate Change

• Climate change affects environmental factors such as temperature, precipitation patterns, and sea levels, leading to habitat loss.

• Human populations face increased extreme weather events, resulting in property damage and loss of life.

• Forced migration may occur as communities relocate due to uninhabitable conditions.

• Agricultural impacts include reduced crop yields and increased pest outbreaks, threatening food security.

• Energy and water security are also jeopardized, necessitating adaptive strategies.

Strategies for Managing Climate Change

• Reducing greenhouse gas emissions can be achieved through lifestyle changes, such as adopting a plant-based diet and energy-efficient practices.

• Transitioning to low-carbon fuels and alternative energy sources is crucial for long-term sustainability.

• Policies promoting reforestation and afforestation can enhance carbon sequestration.

• International agreements like the Kyoto Protocol and Paris Agreement aim to unify global efforts against climate change.

• Geo-engineering strategies, such as solar radiation management, are being explored as potential solu