Human Impact on Earth

Resources and Human Impact on Earth

• Humans impact the earth both directly and indirectly because they need water, soil, and air to survive.
• Activities could be harmful if the use of resources is not carefully planned.
• Water is used for bathing and watering gardens and comprises nearly 70% of our body.
• Human activities have various impacts on soil contamination.
• Human impact is pervasive and profound, sparking discussion about the "Anthropocene", a new geologic era, characterized by anthropogenic disturbance.
• Human activities cause smog, acid rain, global warming, and ozone depletion.
• Human activities also produce particulates like dust, which contribute to respiratory disease.

Key Terms

• Desertification: Expansion of desert conditions in areas where natural plant cover has been destroyed.
• Pollutant: Harmful material entering the biosphere via land, water, or air.
• Acid Rain: Rain containing nitric and sulfuric acids, caused by burning fossil fuels.
• Conservation: Wise management of natural resources, like habitat and wildlife preservation.
• Smog: Mixture of chemicals (smoke + fog), appearing as a gray-brown haze in the atmosphere.
• Ozone Layer: Atmospheric layer with relatively concentrated ozone (O3) gas, protecting from ultraviolet radiation.
• Alternative Energy: Energy generated without depleting natural resources or harming the environment, and avoiding fossil fuels and nuclear power.
• Greenhouse Effect: Natural process where atmospheric gases trap energy from sunlight as heat.
• Deposition: Geological process where sediments, soil, and rocks are added to a landform or land mass.
• Sustainable Development: Using natural resources without depleting them while providing for human needs without long-term harm.
• Renewable Resource: A necessity of life which can regenerate and is replaceable (ex: trees, water).
• Nonrenewable Resource: A necessity of life which cannot be replenished by natural means (ex: fossil fuels).
• Monoculture: Farming strategy of planting large fields with a single crop variety year after year.
• Thermal Energy: The ability to do work through the release of heat.
• Internal Energy: Energy associated with molecular motion (or temperature).
• Latent Energy: Energy associated with the evaporation/condensation of water vapor.
• Kinetic Energy: The ability to do work due to motion.
• Gravitational Energy: The ability to do work through changes in a body's location within a gravitational field.
• Electromagnetic Wave Energy: Energy embedded in electromagnetic wave motion (light, microwaves, x-rays), converted to heat when it impinges on matter.
• Chemical Energy: The ability to do work via a chemical interaction (i.e., change in molecular structure).
• Energy: The ability to do work or cause change.
• Nuclear Fission: The splitting of an atom's nucleus into smaller nuclei.
• Nuclear Fusion: The combining of two atomic nuclei into a single larger nucleus, releasing energy (ex: hydrogen atoms joining to form helium).
• Heat: Energy transferred from a hotter object to a cooler one.
• Heat Transfer: The movement of energy from a warmer object to a cooler object.
• Nuclear Energy: Energy released by a nuclear reaction, especially by fission or fusion.
• Potential Energy: Energy derived from position or condition, rather than motion (ex: raised weight, coiled spring, charged battery).
• Law of Conservation of Energy: The fundamental principle of physics that the total energy of an isolated system is constant despite internal changes.
• Geothermal Energy: Heat energy in Earth's interior from water or steam heated by magma.
• Solar Energy: Energy obtained from solar power.
• Fracking: Nickname for hydraulic fracturing: a technique to retrieve natural gas by creating fractures in rock with large amounts of injected water.
• Natural Gas: Fossil fuel made up of hydrocarbon, methane.
• Crude Oil: Unrefined oil taken from the ground; a fossil fuel.
• Gasoline: Liquid and energy-rich product of refined oil.
• Oil: Liquid fossil fuel from ancient dead organisms, used for transportation and other products.
• Hydropower: Electricity derived from the energy of moving water.

Human Impact - Erosion

• Water, wind, and gravity play a part in the destructive process of erosion.
• Humans must deal with the result of changes in the land.
• Choices are made every day that will in some cases slow the process of erosion and other times will speed up the process of erosion.

Land and Soil

• Soil is a non-renewable resource.
• Soil erosion is the permanent change of the main characteristics of soil.
• Soil erosion could see it lose its fertility, pH, colour, humus content or structure.
• Soil erosion occurs naturally by wind or harsh climatic conditions.
• Human activities cause erosion including overgrazing, overcropping and deforestation.
• Less than a quarter of Earth's surface is dry land, making it a precious natural resource for food, shelter, and obtaining other resources.
• Humans change the lan,d impacting agriculture, development, or mining.
• Human activity causes ten times more soil erosion than all natural processes combined.
• Arable land is ploughed or tilled regularly, generally under a system of crop rotation.
• Overgrazing happens when cattle ranchers, sheep or other grazing animal farmers have too many animals on their land.
• The animals cause damage to the soil by eating too much of the vegetation by digging into the wet soil or compacting the dry soil simply by walking over it with their hooves.

Overcropping

• Continuous cultivation of the land without allowing it to lie fallow between crops will result in overcropping.
• Constant farming of the land reduces the soils ability to produce valuable humus.
• Some farmers attempt to restore fertility to soil by adding fertilizers or artificial nutrients.

Deforestation

• When large area of forest are cut down; that is known as deforestation leaving open, exposed landscape.
• Deforestation occurs for the sale of wood, charcoal or as a source of fuel.
• Deforestation can also occur while the cleared land is used as pasture for livestock, plantations of commodities, and settlements.
• Removing trees can result in damage to habitat, biodiversity loss and drying of the soil.
• Natural erosion will be accelerated.
• Soil erosion will also happen faster because the exposed soil will easily be loosened when it rains heavily.

Development

• Development includes any type of construction.
• Development can reduce the amount of available farmland and can destroy habitats wildlife depend upon.

Low Impact Development and Green Infrastructure

• Low Impact Development is primarily concerned with stormwater.
• Low Impact Landscaping is sustainable landscaping that strives to create beauty with the lowest possible impact on the natural environment within which it exists.
• This type of landscaping design adds a strong emphasis on rainwater

Water

• Water erosion is basically the wearing away of soil, by water.
• Rain splash erosion is caused by the impact of water striking the surface.
• Surface runoff forms when the rainfall from a storm is more than the soil can contain which is when sheet erosion happens.
• Sheet erosion is caused by the unconfined flow of water running across the surface of the land.
• The effects of sheet erosion often go unnoticed because such thin layers of soil are being removed.
• Rill erosion is caused by water concentrating into innumerable.
• Left unchecked, rills can cut vertically and horizontally and when joined form gullies which are steep-sided trenches and are difficult to stop.
• Soil erosion by water is the result of rain detaching and transporting vulnerable soil, either directly by means of rainsplash or indirectly by rill and gully erosion. Rainfall may also move soil indirectly, by means of runoff in rills (small channels) or gullies.

Low Impact Development - Stormwater Management

• Stormwater is rainwater and melted snow that runs off streets, lawns, and other sites.
• In developed areas, however, impervious surfaces such as pavement and roofs prevent precipitation from naturally soaking into the ground.
• Causes downstream flooding, stream bank erosion, increased turbidity from erosion, habitat destruction, changes in the stream flow hydrograph, combined sewer overflows.
• Eventually causes infrastructure damage and leads to contaminated streams, rivers, and coastal water

Wind

• Wind is an effective agent in causing erosion in dry, arid climates like deserts.
• Deflation is the process by which wind removes surface materials.
• Deflation moves the topsoil in an area leaving only stones and rocky materials.

Conservation

• It includes conservation is using natural resources wisely and not contributing to the pollution of the land, air or water
• Pollution: anything that harms or degrades the natural environment
• Conservation can include small-scale clean-up projects along roadways or building fences to prevent dune erosion to large-scale beach renourishment.

Natural Resources

• Natural resources may be further classified in different ways.
• Natural resources are materials and components that can be used that can be found within the environment.
• A natural resource may exist as a separate entity such as fresh water, and air, as well as a living organism such as a fish, or it may exist in an alternate form which must be processed to obtain the resource such as metal ores, oil, and most forms of energy.
• There are nine major areas of energy resources falling into two categories; nonrenewable and renewable.
• Nonrenewable energy resources, like coal, nuclear, oil, and natural gas, are available in limited supplies.
• Renewable resources are replenished naturally and over relatively short periods of time composed of solar, wind, water (hydro), biomass, and geothermal.
• Fossil fuels make up a large portion of today's energy market, although promising new renewable technologies are emerging.

Nonrenewable Resources

• A nonrenewable resource is a natural resource that can not be re-made or re-grown at a scale comparable to its consumption (Coal, Petroleum and natural gas).
• The resources are fossil fuels not replenished in a short period.
• There are four main types of coal including anthracite, bituminous, subbituminous, and lignite.
• There are two types of coal mining; surface mining and underground mining.
• Surface mining is used more because it is less expensive.
• After the coal is digged out of the ground, it goes to a preparation plant which is in a mining site to then be taken by truck.

How is Natural Gas Made?

• Natural gas forms under the same conditions that create oil.
• Microorganisms, sea plants and animals died over 300 million years settling on the bottom of the oceans which covered most of the earth.
• Over time the pressure and heat turned them into petroleum and natural gas.
• The natural gas would get trapped in pockets of underground rocks.
• Natural gas in it's pure form is colorless, odorless and shapeless, with the "rotten egg" odor added for safety.
• Millions of years ago, remains of plants and animals decayed and built up into thick layers called organic material
• Over time, the changed to rock, covered the organic material, and trapped it below the rock.
• Natural gas use is biggest in the Rocky Mountain states, Texas, and the Gulf of Mexico region; California also stores it.

Extracting Natural Gas

• Most natural gas comes from the wells that produce petroleum.
• Hydraulic fracturing, called fracking, makes it quicker to get natural gas from the rock.
• Chemicals in the fluid prevent the fractures from closing from preventing the natural gas pumped to the surface.

Consequences of Natural Gas Extraction and Use

• Natural gas burns cleaner than other fossil fuels; as a result, it causes less air pollution.
• Fracking is destructive due to harmful chemicals, endocrine disruptors which can also cause earthquakes.

Petroleum/Oil

• Oil is a naturally occurring, toxic, flammable liquid that is mixed with hydrocarbons.
• Oil is formed with the remaining of animals and plants that have been here over one million years that heat/pressure and turn into crude oil made obtainable through oil drilling.
• Oil is found in rock layers of Earth's crust with primary use for energy.
• Tiny organisms die and settles into the bottom to coal which when exposed to high heat/pressure over the years transforms into liquid oil.
• Oil moves through permeable rock and is trapped by the impermeable cap rock.
• Oil comes out of the ground as crude oil which boils at different tempatures to produce gas or other such things.
• These fuels (oil and gas) provide about 90% of the energy used for transportation around the world.
• Using gasoline to power automobiles affects the environment causing damage to the environment (air pollution and smog).

Nuclear Energy

• Nuclear fission uses uranium to create energy.
• Nuclear energy is a nonrenewable resource.
• A renewable resource is a natural resource which can replenish with the passage of time, either through biological reproduction or other naturally recurring processes.

Renewable Resources

• These resources are part of Earth's natural environment/ its ecosphere.
• Renewable energy sources including biomass, hydropower, geothermal, wind, and solar provide 8% of the energy used in the United States, mostly to produce electricity.
• Renewable energy has generally been more expensive than fossil fuels and is often located in Remote areas limiting its availability and power.

Biomass

• Biomass is organic material made from plants and animals containing stored energy from the sun (wood, crops, manure, some garbage).
• Burning biomass is not the only way to release its energy; its energy can be turned into useable sources (methane gas and transportation fuels).
• Methane gas is the main ingredient of natural gas that smells like rotting garbage, and agriculture and human waste, release methane gas also called "landfill gas" or "biogas".
• Biomass may result in more or less air pollution depending on the type of biomass and the types of fuels or energy sources that it replaces.

Geothermal

• The word geothermal comes from the Greek words geo (earth) and therme (heat); geothermal energy is heat from within the Earth.
• Geothermal energy is the heat from the Earth; It's clean and sustainable used to generate electricity or heat homes and buildings.

Wind Power

• Wind power also indirectly taps Earth's solar energy flux, which causes differences in atmospheric temperatures.
• Several European countries have made major investments in wind energy to generate electricity without producing air pollutants or greenhouse gases.

Hydropower

• Hydropower generates electricity due to moving water.
• Over half of States is concentrated in Washington, Oregon, and California.
• The waves crash onto the ocean with tremendous levels of force.

Solar Power

• Solar energy is the sun's rays (solar radiation) that reach the Earth.
• The main benefits of solar energy include avoiding air pollutants or carbon-dioxide.

Wasting Resources

• Using one's resources wisely will keep one from not having enough of that resource.
• 10 percent of the total U.S. energy budget to get food from the farm to a fork.
• Fifty percent of U.S. land is used for farming/ eighty percent of freshwater is used through the process of growing, harvesting, processing, shipping, stocking, selling and transporting food, however, forty percent of that food goes uneaten.
• North America consumes one third of the world's resources and produces on half of the world's garbage.

Composting

• Composting is organic matter that has been decomposed and recycled as a fertilizer and soil amendment.
• Compost is a key ingredient in organic farming
• Aerobic bacteria and fungi manage the chemical process by converting the inputs into heat, carbon dioxide and ammonium.

Pollution

• Pollution is anything that puts something harmful into the natural environment, called a pollutant.
• Contaminants in the landfill can leach into the nearby soils and groundwater leading to Water Pollution, stemming from various sources (industrial/agricultural processes).