APES - Unit 5: Land and Water Uses Modules 29-31

Crustal abundance

-The average concentration of an element in the Earth's crust

-When Earth formed, heavy elements sank towards the core while lighter ones remained near the crustal surface.

-Oxygen, Silicon

Ores

-Concentrated accumulations of minerals that are considered economically viable.

-Could be metals

Metals

-Elements with properties that allow them to conduct electricity and heat.

Surface mining

-The extraction of mineral and energy resources near Earth's surface by first removing the soil, subsoil, and overlying rock strata.

-Strip, open-pit, mountaintop removal, placer

Strip mining

-Removing strips of surface rock

open pit mining

-Creating a large hole in the ground to reach the desired resource

Mountaintop removal

-Removing the top of a mountain with explosives to reach resources below

Placer mining

-Looking for minerals, metals, and stones in river sediments

Mine tailings

-Unwanted waste material created during mining including mineral and other residues that are left behind after the desired metal or ore is removed

Subsurface mining

-Mining more than 100 m below the surface of the Earth.

-Subsurface mining tends to be expensive compared to surface mining methods

-Subsurface mining impacts the air, water, and biodiversity, and can be economically prohibitive due to safety and insurance concerns.

Surface mining: effects on air

Significant dust from earth-moving equipment

Surface mining: effects on water

Contamination of water that percolates through tailings

Surface mining: effects on soil

Most soil removed from site; may be replaced if reclamation occurs

Surface mining: effects on biodiversity

Habitat alteration and destruction over the surface areas that are mined

Surface mining: effects on humans

Minimal in mining process, but air quality and water quality can be adversely affected near the mining operation.

Subsurface mining: effects on air

Minimal dust at the site, but emissions from fossil fuels used to power mining equipment can be significant.

Subsurface mining: effects on water

Acid mine drainage as well as contamination of water that percolates through tailings

Subsurface mining: effects on biodiversity

Road construction to mines fragments habitat

Subsurface mining: effects on humans

Occupational hazards in mine; possibility of death or chronic respiratory diseases such as black lung disease.

Urbanization

-The process of an area becoming more urban, or increasing the density of people per unit area of land

-Urban populations represent 55% of the human population and are responsible for consuming 75% of Earth's resources.

Suburbs

-Areas that surround metropolitan centers with lower pop. densities than urban areas

-Recently urban areas have become denser in population, leading to an increase in numbers of suburbs

Exurbs

-Like suburbs, but typically more rural and not usually connected to a central city or densely populated area.

-An estimated 2/3 of people live in suburban or exurban communities.

Urban sprawl

-The movement of urbanized areas into rural areas w/ clusters of housing, retail shops, office parks, and miles of road separating them

Main causes of urban sprawl:

-Increased availability of automobiles and highways

-Reasonable living costs in the suburbs

-Lack of support for urban communities (urban blight)

-Government policies funding highways and subsidizing mortgages in suburban areas

Issue w movement into urban areas:

-increased congestion and longer commutes.

-more use of aquifers and surface waters for agriculture and municipal use.

Smart growth

-Communities focus on strategies to develop sustainable and health communities --> approach to reduce urban sprawl

-Create sense of place, the feeling that an area has a meaningful character

-Gentrification

The Environmental Protection Agency (EPA) lists the following when considering smart growth:

-Walkable neighborhoods

-Mixing residential, retail, recreational, and business land use

-Encouraging stakeholder collaborations

-Preserving open spaces and natural beauty

Saltwater intrusion.

-Reduced groundwater levels near shorelines have led to an intrusion of saltwater in an area where freshwater was previously found, due to a cone of depression forming

Impervious surfaces

-Pavement or other surfaces that do not allow water penetration, can also lead to reduction of infiltration of precipitation and more flooding due to runoff.

-EX: Concrete, asphalt

Urban runoff

-Occurs when water from an urban area doesn't evapotranspire or infiltrate the soil.

-Reducing impervious surfaces would mitigate this issue, as well as creating places where water can flow to rather than remain in one area and cause flooding.

-Urban systems can also collect rainwater and repurpose it to gardens or for watering lawns.

-Increasing the planting of trees, even in urban areas, can reduce runoff as well.

Ecological footprint

-A measure of the area of land and water an individual, population, or activity requires to produce all the resources consumed, and process the waste generated.

-Typically measured in biologically reproductive land in hectares (ha) (1 ha = 2.47 acres).

-People in developed nations tend to have a larger footprint than those in developing nations.

Ecological footprint can be calculated by summing up land required for:

-Food eaten

-Water used

-Energy used

-Clothing worn

-Housing and transportation

Earth Overshoot Day

-The day when humanity consumes more resources than the Earth can regenerate in that year

-After Earth Overshoot Day humanity operates on ecological deficit spending.

-2024 Global: Aug 1st

Carbon footprint

-Measure of the total carbon dioxide and other greenhouse gas emissions released through activities, both directly and indirectly, by a person, country, or other entity.

-CO2 + other greenhouse gases such as CH4

-Generally estimated

Critiques of Carbon Footprint

-Doesn't account for pollution

-Heavy focus on land and resources

-Heavy focus on "useful" resources

-Oversimplification of individual responsibility

-Potential for corporate greenwashing