Sustainable Development and Natural Hazards: A Comprehensive Guide

Posted on Aug 29, 2024 in Geology

Ecosystem and Natural Resources

What is an Ecosystem?

An ecosystem consists of a physical environment characterized by factors like temperature, humidity, and salinity. It also includes the organisms living within it, forming a community, and the relationships between them.

What are Natural Resources?

Natural resources are anything obtained from nature by humankind to meet their needs.

Sustainable Development

Definition

Sustainable development meets the needs of the present without compromising the ability of future generations to meet their own needs. It represents a balance between economy, ecology, and society.

Key Concepts

• Carrying Capacity: The ability of an ecosystem to sustain life within it.
• Ecological Footprint: The area required to produce the resources humans consume and assimilate the waste generated.

Principles of Sustainable Development

1. Sustainable Extraction: Resource exploitation should be less than or equal to its regeneration rate.
2. Sustainable Discharge: Non-renewable resource extraction should be equivalent to the creation of renewable substitutes.
3. Sustainable Emission: Waste emission should be less than or equal to the environment’s assimilative capacity.
4. Zero Emissions: Reduce pollutant emissions to zero.
5. Integration of Sustainable Urban Settlements: Urban development should not exceed the carrying capacity of the territory.
6. Selection of Sustainable Technologies: Encourage the use of more efficient technologies.
7. Precautionary Principle: Employ development models that operate within the limits of ecosystems.

Water Resources

Water Usage and Waste

• Wasting (70%): Primarily in agriculture, followed by industry (22%) and urban areas (8%).
• Non-Wasting: Navigation and renewable energy generation.

Water Conservation Measures

• Agricultural: Efficient irrigation techniques and utilizing indigenous vegetation.
• Industrial: Implementing low-power technologies and recycling water after cooling processes.
• Urban: Using low-power devices, water purification, reuse, and promoting environmental education.

Technical and Policy Measures for Water Management

• Technical: Construction of dams and reservoirs, water transfer projects, channeling, and desalination.
• Policy: Enacting laws and domestic or international agreements.

Biosphere Resources

Biodiversity

Biodiversity refers to the variety of organisms and ecosystems within a specific area or across the entire Earth.

Soil

Soil is a thin layer covering land, composed of minerals, organic matter, living organisms, air, and water. It supports plant growth and is utilized for agriculture, mineral extraction, and rock quarrying.

Agricultural and Livestock Resources

Agriculture can be categorized as subsistence, intensive, or environmentally friendly. Practices like artificial irrigation, deforestation, excessive use of chemical fertilizers and pesticides, and genetic manipulation of seeds contribute to environmental problems such as wastewater contamination, soil depletion, and reduced biodiversity.

Ecological Agriculture

Ecological agriculture, also known as organic farming, relies on natural resources without synthetic chemicals or genetically modified organisms. This approach prioritizes food production while preserving soil fertility and respecting the environment.

Fishery Resources

Common fishing methods include longline, bottom trawl, driftnet, and purse seine fishing.

Forest Resources

Forests provide numerous benefits, including fresh air, food, timber, and recreational spaces.

Energy Resources

Conventional Energy Sources

• Renewable Fuels: Derived from swamps (coal) and marine environments (oil and natural gas).
• Nuclear Fission: Splits the nucleus of an atom, resulting in lighter elements. Uranium is a common fuel source.
• Hydropower: Modifies river flow regimes, potentially impacting migratory fish populations.

Alternative Energy Sources

• Solar Power: Harnesses solar energy through solar cells or photovoltaic panels.
• Wind Power: Utilizes wind turbines, often grouped together in wind farms.
• Biomass Energy: Converts organic waste into electricity or biofuels.
• Geothermal Energy: Extracts heat or electricity from underground steam or hot water.
• Tidal Energy: Employs dams to capture tidal flows, driving turbines for electricity generation.
• Hydrogen Fuel: Produced through the electrolysis of water.

Natural Hazards and Disasters

Definitions

• Natural Hazard: Any natural process that poses a threat to human life or property.
• Disaster: The disruptive impact of an extraordinary natural phenomenon or process on a territory and its inhabitants.
• Catastrophe: Occurs when the consequences of a disaster are so severe that external assistance is required.

Factors Influencing Risk

• Uncontrolled Population Growth
• Global Warming
• Ecosystem Destruction
• Overexploitation of Water Reserves
• Poverty

Risk Assessment Components

• Threat Level: Probability of a hazardous event, measured by magnitude and return period (frequency).
• Vulnerability: Potential damage and losses, assessed on a scale from 0 (no damage) to 1 (total loss).
• Exposure: The number of people or assets at risk.

Formula for Risk

Risk (R) = Threat Level (P) x Vulnerability (V) x Exposure (E)

Specific Natural Hazards and Mitigation Strategies

Volcanic Hazards

• Eruption Types: Hawaiian, Strombolian, Plinian, and Vulcanian, each with varying return periods and explosiveness.
• Risks: Gases, lahars (volcanic mudflows), and ashfall.
• Prediction: Monitoring tremors, temperature changes, noises, and gas emissions.
• Prevention: Land-use planning, sloped roofs, fireproof shelters, and evacuation plans.

Seismic Hazards (Earthquakes)

• Magnitude: Measures the energy released by an earthquake.
• Intensity: Assesses the effects and damage based on structural impact and human perception.
• Depth of Focus and Material Types: Influence the extent of damage.
• Earthquake Cycle: Includes periods of inactivity, elastic strain accumulation, foreshocks, and the main rupture event.
• Prediction: Long-term forecasting based on micro-earthquakes, ground deformations, historical earthquake patterns, and animal behavior.
• Prevention: Earthquake-resistant building codes, land-use planning, and public education.

Tsunamis

• Definition: Large waves caused by the vertical displacement of a massive volume of ocean water.
• Sources: Earthquakes, volcanic eruptions, landslides, and asteroid impacts.
• Detection and Warning: Gauges and tsunamometers can detect tsunamis due to their long wavelengths.

Saline Diapirs

• Formation: Upward movement of salt masses due to their low density.
• Risks: Ground instability and potential for sinkholes.
• Mitigation: Preventing water infiltration to avoid salt dissolution and injecting voids with solid materials.

Sinkholes

• Collapse Sinkholes: Sudden and rapid collapses often occurring in karst regions, mining areas, or due to saline diapirs.
• Subsidence Sinkholes: Gradual sinking caused by soft ground, fluid extraction, or changes in groundwater levels.
• Mitigation: Geophysical methods to locate underground cavities and risk mapping.

Expansive Soils

• Characteristics: Soils that change volume with hydration and dehydration cycles.
• Risks: Damage to building foundations and infrastructure.

Dune Movement

• Cause: Displacement of sand masses by wind.
• Risks: Encroachment on settlements, agricultural lands, and roads.
• Prevention: Constructing barriers and revegetation efforts.

Slope Movement

• Natural Factors: Slope angle, soil type, water saturation, and earthquakes.
• Human Factors: Construction activities, deforestation, and altering slopes.
• Types of Slope Movement: Avalanches, landslides, flows, and creeps.

Avalanches

• Definition: Rapid movement of snow and ice down steep slopes.
• Conditions: Snowpack exceeding a critical load and low cohesion within the snow layers.
• Causes: Rain, temperature changes, cracks in the snowpack, vibrations, and human activities.
• Prediction: Observing signs of previous slides, changes in slope convexity, and deformation of vegetation.
• Prevention: Constructing barriers, nets, anchors, drainage systems, and revegetation.

Tropical Cyclones

• Definition: Large rotating storms with low pressure centers, forming over warm tropical waters (hurricanes in the Atlantic, typhoons in the Pacific).

Tornadoes

• Definition: Violent rotating columns of air extending from a thunderstorm to the ground.

Cold Air Drops (Gota Fría)

• Definition: Weather phenomenon characterized by a sudden drop in temperature, often occurring in late summer or early autumn.

Floods

• Types: Coastal and riverine flooding.
• Causes: Heavy rainfall, prolonged precipitation, dam failures, sea-level rise, and human activities.
• Risk Factors: Energy of rivers and streams, measured by discharge (Q = Area x Velocity).
• Prediction: Weather forecasting, historical flood data, and risk maps.
• Prevention: Building levees and embankments, afforestation, land-use regulations, civil protection measures, and flood insurance.