Natural Resources and Their Exploitation: A Comprehensive Guide
1. Natural Resources
What are Natural Resources?
Natural resources are the various elements of nature that humans utilize for their benefit.
Human Exploitation of Natural Resources
The phrase “mankind increases the exploitation of natural resources far above their growth” highlights the fact that humanity’s consumption of natural resources exceeds the rate at which these resources can replenish themselves. This is known as overexploitation. Examples include the overuse of oil despite its long formation time, the depletion of forests due to paper consumption, and so on. The rate of resource exploitation significantly surpasses population growth. For instance, a city’s population might increase by 5%, while its energy consumption rises by 10%.
Types of Natural Resources
Renewable Resources
Renewable resources are those that are inexhaustible, such as solar energy, wind energy, and ocean tides.
Nonrenewable Resources
Nonrenewable resources exist in limited quantities and are the most exploited today. Examples include oil, coal, and natural gas.
Potentially Renewable Resources
These resources can be renewable if their rate of regeneration exceeds the rate of human exploitation. This category includes biological resources like agriculture and fisheries.
2. The Hydrosphere
What is the Hydrosphere?
The hydrosphere encompasses all the liquid, gaseous, and solid water components of the Earth. It includes seas, rivers, lakes, groundwater, ice caps, glaciers, and atmospheric clouds.
The Water Cycle
Solar energy heats water in oceans and continents (groundwater and rivers), causing evaporation. Transpiration from plants also contributes to water vapor in the atmosphere. This water vapor condenses and precipitates as rain, snow, hail, dew, or frost on continents and oceans. Water falling on land either flows towards the sea (through tributaries, streams, and rivers) or infiltrates the ground to become groundwater, eventually resurfacing in wells, oases, and springs.
Human Impact on the Water Cycle
Humans alter the water cycle by constructing dams, reservoirs, and pipelines. We utilize water for domestic consumption (cleaning, drinking), public services (water parks), agriculture (irrigation), livestock (food and cleaning), industry and mining (manufacturing, coolant), and as an energy source.
Uses of Water
- Domestic and Public Consumption: Drinking, cleaning, and watering.
- Agriculture (73%): Primarily for irrigation. Methods include flood irrigation, drip irrigation, and sprinkler irrigation. Drip irrigation is the most efficient (30% water savings), while flood irrigation, the most common, leads to significant water waste.
- Livestock: Animal hydration and waste cleaning.
- Industry and Mining: Cooling processes and manufacturing various products.
- Electricity Generation: Hydroelectric power generation.
Water Consumption
Agriculture is the largest consumer of freshwater, accounting for 73% of total usage. This water is primarily used for irrigation, and despite the existence of various irrigation methods, the most prevalent method, flood irrigation, results in substantial water loss.
Water Scarcity
Water is considered a “fragile resource” because it is essential for human survival yet faces increasing pressure due to population growth, industrial and agricultural expansion, and rising living standards.
Solutions to Water Scarcity
Addressing water scarcity requires raising awareness, improving water management and distribution, promoting water conservation education, and fostering respect for water resources. Implementing new technologies for water reuse and consumption reduction is crucial.
Water Situation in Spain
Spain is a water-scarce country with less than half the global average water resources per capita. Despite this, Spain has the highest water consumption rate in Europe, partly due to its reliance on agriculture and livestock, which account for 78% of water usage.
3. Soil
What is Soil and How Does Human Activity Affect It?
Soil is a natural layer approximately 2 meters thick, composed of mineral matter, organic matter, living organisms, water, and air. Human activities have significantly impacted soil, causing depletion, erosion, desertification, and contamination. Soil conservation is vital as it supports food production and is essential for human survival.
Agriculture and Soil Degradation
The agricultural population has grown faster than the overall population, achieved without increasing cultivated land area. This is primarily due to new farming practices involving fertilizers, pesticides, and improved machinery. However, these advancements have led to environmental problems, including:
- Pollution and soil depletion from pesticide, herbicide, and fertilizer use.
- Soil salinization due to new crop varieties requiring large amounts of water.
- Uniformity of seeds, reducing biodiversity and pest resistance.
- Soil compaction from mechanization, reducing porosity and hindering root growth.
Global Hunger
Over 850 million people worldwide suffer from hunger due to unequal food distribution. Sustainable agriculture can be a potential solution.
Mining and Environmental Impacts
Mining activities have several environmental consequences:
- Severe land disturbance, including excavations that can eliminate vegetation and promote erosion.
- Alterations in plant and animal populations.
- Water pollution from mineral washing, affecting groundwater and surface water.
- Air pollution from dust generated by blasting and heavy machinery.
- Morphological and visual impacts caused by sterile accumulation, landscape changes, tunnels, and terraces.
Intensive Farming and Its Consequences
Intensive farming involves raising as many animals as possible in confined spaces within the shortest possible time, relying on processed feed and sometimes hormones. These practices can have adverse effects on consumers.
4. Fishing and Marine Resources
Fishing and Its Impact
Fishing, the capture of aquatic species, has led to a significant reduction in biodiversity due to non-selective fishing nets (catching unwanted species) and trawling (damaging the seabed).
The 1973 Convention on the Law of the Sea
This convention established a 200-mile exclusive fishing zone for each country, granting them responsibility for safeguarding biodiversity and water quality within their zone. International waters were declared the common heritage of mankind but have faced serious violations, including the hunting of protected species, illegal fishing nets, and ocean dumping.
Climate Change and the Marine Environment
Climate change is the most serious threat to the marine environment, driving biodiversity loss as marine organisms struggle to adapt to rising temperatures.
Solutions to Overexploitation of Marine Resources
Addressing overexploitation requires global adherence to international laws, adopting environmentally friendly fishing technologies, implementing stricter regulations on fishing nets, enforcing biological rest periods during breeding seasons, establishing marine reserves, and preventing the consumption of juvenile fish. Aquaculture can also be a sustainable alternative.
5. Energy Resources
Coal
Coal is a carbon-rich mineral formed from decomposed plant material. Its combustion generates greenhouse gases and contributes to acid rain. Coal is primarily used for electricity generation in power plants.
Oil
Oil is a viscous liquid formed from the decomposition of marine microorganisms. It is a crucial resource used to produce gasoline, diesel, and plastics. Oil reserves are declining, and most are located in the Middle East, necessitating transportation via pipelines and ships. Oil spills during transport and greenhouse gas emissions from combustion are major environmental concerns.
Natural Gas
Natural gas is a mixture of gases, primarily methane (CH4), formed from decaying organic matter. It is transported via pipelines from oilfields, mainly in the Middle East and Russia. Natural gas burns cleaner than other fossil fuels, producing fewer greenhouse gases.
Nuclear Energy
Nuclear energy involves either nuclear fusion (combining atoms) or nuclear fission (splitting atoms). Fusion requires extremely high temperatures, making it currently impractical. Fission generates radioactivity and carries the risk of accidents and nuclear weapons proliferation. However, it is a clean energy source as it does not produce greenhouse gases. Nuclear power plants generate electricity by using the heat from fission to produce steam, which drives turbines connected to generators. The main drawbacks are the hazardous radioactive waste and the potential for accidents.
Solar Energy
Solar energy harnesses sunlight for human use and can be either thermal or photovoltaic. Solar thermal energy involves absorbing solar heat with a fluid, primarily for heating or generating electricity through steam turbines. Photovoltaic solar energy utilizes semiconductor cells that release electrons when exposed to light, generating electricity. This energy can be stored in batteries. Solar energy is significant due to its abundance and minimal environmental impact. Legislation in Spain promotes solar energy use in new buildings.
Renewable Energy Sources
Hydropower
Operation: Harnesses the energy of flowing water in rivers or dams to generate electricity through turbines.
Environmental Impact: Reduced biodiversity, disruption of fish migration, decreased river flow, microclimate changes, visual impact.
Wind Energy
Operation: Wind turbines (windmills) utilize wind power to generate electricity.
Environmental Impact: Visual impact, potential threat to birds.
Tidal Energy
Operation: A dam built across a bay captures tidal flow, generating electricity as water flows through turbines during both high and low tides.
Environmental Impact: Changes in marine ecosystems, erosion, sedimentation.
Biomass Energy
Operation: Utilizes organic waste from agriculture, livestock, and municipal sources for energy production through direct combustion or other processes.
Environmental Impact: Generates harmful gases, but does not contribute to acid rain due to the absence of sulfur.
Hydrogen Energy
Operation: Hydrogen can be combusted to release energy and water or used in fuel cells to generate electricity and water through electron exchange.
Environmental Impact: The main drawback is CO2 emissions during hydrogen production from natural gas.
Nuclear Fusion
Operation: Involves fusing light atomic nuclei at extremely high temperatures, currently under research using magnetic fields for containment.
Environmental Impact: Does not generate radioactive waste and releases vast amounts of clean energy, making it a promising future energy source.