GE ELECT 4 - midterms Flashcards
means the surrounding external conditions influencing development or growth of people, animal or plants; living or working conditions, etc. (Singh, 2006)
* living & non-living
* our built environment
* social relationships and institutions
Environment
understanding the environment
lithosphere - solid earth
atmosphere - gases (air)
hydrosphere - all water
biosphere - all life
- Is define as the
interdisciplinary study of humanity’s relationshipwith other organisms and the nonliving physical environment. - It is the academic field that takes physical, biological, and chemical sciences to study the environment and discover solutions to environmental problems.
Environmental Science
and the issues that it studies are complex and interdisciplinary.
Includes concepts and ideas from
multiple fields of study.
Decisions have impacts in all these
fields of study.
Environmental science
Drawing a Bridge of Info
Envi Science
- A community decides to use coal for electricity, as it is the cheapest source available. (Economics)
- The coal must be mined from under the soil. (Geology)
- The coal must be transported to the population center by road or rail. (Engineering)
- When it is burned at a power plant, air pollution is released. Some of that pollution is converted to acid in the atmosphere. (Chemistry)
- This falls as acid rain somewhere downwind. (Meteorology)
- The acid stresses plants by affecting their nutrient absorption. (Ecology)
- Laws are passed requiring the plant to install pollution scrubbers. (Politics)
Why study envi science?
- We depend on our environment
- Environmental Science is our modern way of seeking answers to the questions
- Our environment improves the quality of our lives
- Environmental science teaches us how to protect our environment in the face of rising human population and anthropogenic activities that degrade natural resources and ecosystems.
is the discipline that studies the moral relationship of human beings to the environment.
- What is the value of the environment?
- What moral responsibility do we have in dealing with the major environmental problems that result from our resource consumption?
- Which needs should be given the highest priority in our decision
making?
Environmental ethics
It is the view or belief that human beings are superior to all other organisms
- This set of ethics protects and promotes of human interests or well-being at the expense of all other factors.
- often places an emphasis on short-term benefits while disregarding long-term consequences
anthropocentrism
It is a perspective that places importance on the ecosystem as a whole.
The preservation of ecosystems or other living things takes priority over human needs.
ecocentrism
The debate about whether to build a dam in the Hetch Hetchy valley was one of the first big debates between these two philosophies.
- When the growing city of San Francisco, California proposed building a dam in the Hetch Hetchy Valley to provide a steady water supply, Congress debated whether to make a water resource available or preserve a wilderness between 1908 and 1913.
- The dam was eventually constructed.
- The justification for building it was best stated by Gifford Pinochet, the first man in charge of the U.S. Forest Service.
- “Where conflicting interests must be reconciled, the question shall always be answered from the standpoint of the greatest good of the greatest number in the long run.“
hetch hetchy debate
The focus of the resource conservationists was to protect open land.
The National Parks system, and the National Forest system were both created during this time.
Resources Conservationist
-
Silent Spring— Rachiel Carson - pestacides like DDT were having on wildlife
- this began
public awakening to threats of pollution and toxic chemicalsto humans as well as other specie
Modern Environmentalism
explores issues and problems over the entire world, not just within the local community.
Following the 1970s, environmentalism began to consider issues that affected the entire planet:
* Biodiversity loss
* Food production
* Climate Change
* Human population growth
* Economic inequality between nations
Global environmentalism
Demographic Divide
Developing vs Developed Countries
Developing Countries
1. economically poor
1. less educated
1. higher fertility rates
1. lower standart of living
1. lower rates of consumption
Developed Countries
* economically wealthy
* more educated
* lower fertility rates
* higher standard of living
* higher rates of consumption
Four Basic Principles of Envi Science
- Systematic principle of envi
- Principle of envi capacity
- Symbiosis principle between human and envi
- entropy principle
It is the scientific study of interactions between different organisms and between organisms and their environment or surroundings
ecology
Variability among living organisms from all sources including, terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part;
* diversity within species, between species and of ecosystems
- Genetic
- Organismal
- ecological
Biological Diversity
- encompasses the components of the genetic coding that structures organisms and
variation in the genetic make-up of individuals - this is the
raw materialon which evolutionary processes act - the most basic measure of genetic diversity is genome size— the
amount of DNA (deoxyribonucleic acid)in one copy of a species’ chromosomes - humans === 4.5 pg (3.4 billioin bases pairs)
genetic diversity
measures of organismal diversity thus include some of the most familiar expressions of biodiversity, such as the numbers of species (i.e. species richness).
high species richness === more types of species in one place (a)
a. 3 cats, 2 horses, 9 fishes
b. 100 birds
Organismal Diversity
Ecological Organization
- Species Group of organisms so similar to another that they can breed and produce fertile offspring.
- Population is a group of individuals of a single species living together within a particular geographic area. They interbreed and compete with each other for resources.
- Community Different populations that live together in a defined area.
- Ecosystem A collection of all organisms that live in a particular place together with their nonliving environment.
- Biome A group of ecosystems that have the same climate and similar dominant communities.
- Biosphere The portion of earth that supports life is called the biosphere. The biosphere extends several km up in the atmosphere to the deepest parts of the oceans.
The simplest definition of an __________ is that it is a community or group of living organisms that live in and interact with each other in a specific environment (Ecosystem: Definition, Importance, Examples, Human Causes and Effects, 2020)
ecosystem
Types of Ecosystem
-
NATURAL ECOSYSTEM
Totally dependent on solar radiation e.g. forests, grasslands, oceans, lakes, rivers, and deserts. They provide food, fuel, fodder, and medicines. -
MANMADE ECOSYSTEM
Dependent on solar energy-e.g. agricultural fields and aquaculture ponds.
- are the multitude of benefits that nature provides to society.
- make human life possible by, for example, providing nutritious food and clean water, regulating disease and climate, supporting the pollination of crops and soil formation
Ecosystem services
TYPES OF ECOSYSTEM SERVICES
-
Provisioning Services- goods that directly benefit people. -
Regulating services- processes that moderate natural phenomena -
Cultural Services- a non-material benefit that contributes to people’s intellectual, cultural and social development. -
Supporting services- indirect or very long-term impacts on people, but underlie other ecosystem services, particularly provisioning services.
What shapes an ecosystem
plant community -> habitat -> Ecosystem
Biotic and Abiotic factors determine the survival and growth of an organism and the productivity of the ecosystem in which an organism lives.
Biotic - living
Abiotic - non-living
Sunlight is the main energy source for life on earth
Also called autotrophs
Use light or chemical energy to make food
1. Plants
1. Plant-like protists (algae)
1. Bacteria
Photosynthesis—use light energy to convert carbon dioxide and water into oxygen and carbohydrates
(Remember: 6CO2 +6H2O Light Energy 6O2 +
C6H12O6)
Chemosynthesis—performed by bacteria, use chemical energy to produce carbohydrates.
producers
—use light energy to convert carbon dioxide and water into oxygen and carbohydrates
(Remember: 6CO2 +6H2O Light Energy 6O2 +
C6H12O6)
Photosynthesis
—performed by bacteria, use chemical energy to produce carbohydrates.
Chemosynthesis
Organisms that rely on other organisms for their energy and food supply.
Also called heterotrophs
consumers
Types of Consumers
- Herbivores - obtain energy * by eating only plants.
- Carnivores - eat only animals
- Omnivores - eat both plants and animals
- Decomposers - breaks down dead organic
Energy flows through an ecosystem in one direction— from the sun or inorganic compounds to autotrophs (producers) and then to heterotrophs (consumers)
feeding interaction
It is a series of steps in which organisms transfer energy by eating and being eaten
1. Arrows go in the direction of how energy is transferred
2. Start with producer, end with top consumer
food chain
Types of Food chain
-
Grazing Food Chain
The grazing food chain starts with living plants (producers) being eaten by herbivores, which are then eaten by predators. -
Detritus Food Chain
The detritus food chain starts with dead organic matter (detritus) being broken down by decomposers, which are then consumed by detritivores and predators.
is a detailed interconnecting diagram that shows the overall food relationships between organisms in a particular environment. It can be described as a “who eats whom” diagram that shows the complex feeding relationships for a particular ecosystem.
food web
, also known as a trophic or ecological pyramid, is a graphical representation of the energy found within the trophic levels of an ecosystem.
shows relative amount of energy available at each trophic level.
*
* Organisms in a trophic level use the available energy for life processes (such as growth, photosynthesis, cellular respiration, metabolism, etc.) and release some energy as heat.
Remember: Every chemical process that happens in your
body releases heat as a byproduct (ex: burning calories).
*
* Rule of 10—only about 10% of the available energy within a trophic level is transferred to the next higher trophic level.
energy pyramid
shows the flow of energy between various levels. Producers and consumers make up the __________, which displays all their comparative masses at the same time. To create the ___________, the approximate masses are stacked up according to a well-established hierarchy
biomass pyramid
The movement of nutrient elements through the various components of an ecosystem is called nutrient cycling. Another name of nutrient cycling is biogeochemical cycles (bio: living organism, geo: rocks, air, and water)
biogeochemical cycles
The ___________ describes the process in which carbon atoms continually travel from the atmosphere to the Earth and then back into the atmosphere.
steps:
* Photosynthesis
* Respiration
* Decomposition
* Combustion
carbon cycle
The _________ refers to the cycle of nitrogen atoms through the living and non- living systems of Earth. The nitrogen cycle is vital for life on Earth. Through the cycle, atmospheric nitrogen is converted to a form which plants can incorporate into new proteins.
Main processes
1. Nitrogen Fixation
1. Nitrification
1. Assimilation
1. Ammonification
1. Denitrification
nitrogen cycle
The __________ describes how water is exchanged (cycled) through Earth’s land, ocean, and atmosphere.
Process :
1. Evaporation
1. Condensation
1. Precipitation
water cycle
is the circulation of phosphorus in various forms through nature. Of all the elements recycled in the biosphere, phosphorus is the scarcest and therefore the one most limiting in any given ecological system.
Phosphorus cycle
is the process by which the mix of species and habitat in an area changes over time. Gradually, these communities replace one another until a “climax community”—like a mature forest—is reached, or until a disturbance, like a fire, occurs.
* primary — limited
* secondary — destruction of habitat = new plant species
Ecological succession
—when two organisms of the same or different species attempt to use an ecological resource in the same place at the same time. Ex: food, water, shelter
Competition
—the ecological niche involves both the place where an organism lives and the roles that an organism has in its habitat.
Niche
A given habitat may contain many different species, but each species must have a different niche. Two different species cannot occupy the same niche in the same place for very long. This is known as the ____________.
competitive exclusion principle
~~~
```Another aspect of a species‘ niche is its _______. It is the physical environment in which a species lives and to which it is adapted.
habitat
—one organism captures and feeds on another organism
* Predator—one that does the killing
* Prey—one that is the food
Predation
—any relationship in which two species live closely together.
Symbiosis
SYMBIOSIS TYPES
-
Mutualism - both species benefit (
WIN-WIN)
eg. insects & flowers -
Commensalism - one member of the association benefits and the other is neither helped nor harmed (
WIN-0)
eg. barnacles on a whale -
Parasitism - one organism lives on/inside another organism(host) and harms it by obtaining all/part of its nutrions (
WIN-LOSE)
eg. fleas on a dog
- a founder of modern ecology and one of its most provocative thinkers and mobilizers in making environmentalism a people’s political
cause. - Responsible for the first celebration of Earth day in the world.
- His famous book, “The Closing Circle,” published in 1970, provides a clear and understandable example of what ecology truly means.
Everything is connected to everything else
Barry Commoner
Food Chain vs. Food Web
A food chain is a linear sequence of organisms where each is eaten by the next in line, showing who eats whom.
A food web is a more complex network of interconnected food chains in an ecosystem, showing how different organisms are related through multiple feeding relationships.
takes place in a single organism over the span of its life, resulting in a higher concentration in older individuals
Bioaccumulation
takes place as chemicals transfer
from lower trophic levels to higher trophic levels within a food web, resulting in a higher concentration in apex predators.
Biomagnification
COMPETITION vs PREDATION
-
competition arises when resources are in
limited supplyand organisms strive to obtain these resources. -
Predation often greatly
reduces prey population densityand alters community composition and species diversity.
LAW OF THERMODYNAMICS
- First law of thermodynamics: Energy can neither be created nor be destroyed, it can only be transferred from one form to another.
- Second law of thermodynamics: The entropy of any isolated system always increases.
- The mass in an isolated system can neither be created nor be destroyed but can be transformed from one form to another.
LAW OF CONSERVATION OF MASS (MATTER)
- The main role of a _________________ is to recycle the elements on the earth. Biogeochemical cycle enables the transformation of matter from one form to another form. The byproducts of biogeochemical cycles assist the functioning of ecosystems.
biogeochemical cycle
This is, of course, simply a somewhat
informal restatement of a basic law of
physics—that matter is indestructible.
Applied to ecology, the law emphasizes
that in nature there is no such thing as
“waste.” In every natural system, what is
excreted by one organism as waste is
taken up by another as food.
Everything must go somewhere
The third law of ecology holds that
any major man-made change in a
natural system is likely to be
detrimental to that system.
Nature knows best
is important for the growth and
development of an ecosystem. It initiates the colonization of new areas and the recolonization of the areas that had been destroyed due to certain biotic and
climatic factors.
Ecological succession
Exploitation of nature, will always
carry an ecological cost and will
inevitably involve the conversion of
resources from useful to useless.
There is no such thing as a free lunch
An ___________ consists of all the organisms living in a community, as well as the abiotic (non-living) factors with which they interact.
It can be visualized as a functional unit of nature, where living organisms interact among themselves and also with the surrounding physical environment.
It range from small, such as an aquarium, to large, such as a lake or forest.
ecosystem
Energy for life begins with the _____
SUN
is the ability to do work.
Energy
is the amount of energy that moves through a food chain.
- aka Calorific flow
Energy flow
AUTOTROPHS vs HETEROTROPHS
- Autotrophs build molecules themselves using photosynthesis or chemosynthesis as an energy source.
- Heterotrophs depend on the biosynthetic output of other organisms.
FLOW OF ENERGY IN THE ECOSYSTEM
Energy and nutrients pass from primary producers (autotrophs) to primary consumers (herbivores) to secondary consumers (omnivores & carnivores) to tertiary consumers (carnivores that feed on other carnivores).
are consumers that derive their energy from detritus.
- prokaryotes & fungi are important
Detritivores, or decomposers
PRODUCERS
- can make glucose during photosynthesis.
- keep and use most of the energy they make for themselves.
- use cellular respiration to supply the energy for their life functions.
is the process where sugar is converted into carbon dioxide, water, and energy.
Cellular respiration
- The process where the Sun’s energy is converted into chemical energy (Glucose/Sugar).
- Occurs in PLANTS!
- On land, major producers are green plants that contain chlorophyll, which captures light energy.
PHOTOSYNTHESIS
Carbon dioxide + water + light energy → sugar + oxygen
PHOTOSYNTHESIS
are organisms that cannot make their own energy.
CONSUMERS
TYPES OF CONSUMERS
- Herbivore: Eats plants or other producers.
- Carnivore: Eats other animals.
- Omnivore: Eats both plants and animals.
- Scavenger: Feeds on the remains of another organism.
Are called first-orderor primary consumers.
Are herbivores (plant-eaters).
Use most of the energy they get from the producer
Consumers that eat producers to get energy:
Are called secondary or second-order consumers.
May be carnivores or omnivores.
May be predators or scavengers.
Consumers that eat other consumers for energy:
Are called third-order or tertiary consumers.
May be carnivores or omnivores.
May be predators or scavengers.
Consumers that eat a consumer that already ate a consumer:
Are called omnivores.
Eat plants and animals.
Consumers that eat producers and other consumers:
Energy moves from a starting point through living systems in a one-way direction
This movement is described as a flow of energy. The Sun is the major starting point for most living things on Earth.
FOOD CHAIN
are models that demonstrate how matter and energy are transferred between producers, consumers, and decomposers as the three groups interact within the connected food chains in an ecosystem.
Food webs
Energy transfer between trophic levels is typically only _________ efficient.
10%
The atoms of earth and life are the same; they just find themselves in different places at different times.
________ occurs at the local level through the action of the biota.
occurs at the global level through geological processes, such as atmospheric circulation, erosion, and weathering.
Nutrient cycling
The path atoms take from the living (biotic) to the non-living (abiotic) world and back again is called a
biogeochemical cycle.
THE CARBON CYCLE
Plants Use Carbon Dioxide
* Plants pull carbon dioxide (CO2) from the atmosphere.
* Using sunlight with the CO2, they make glucose through photosynthesis.
* The carbon can be used by the plant for food and building materials (cellulose).
* Plants also release CO2 through cellular respiration.
When Animals Eat Plants
* When organisms eat plants, they take in the carbon, and it becomes part of their bodies.
* They generate CO2 through cellular respiration and exhale it into the atmosphere.
Animals Eat Animals
* When organisms eat animals, they take in the carbon, and it becomes part of their bodies.
* They generate CO2 through cellular respiration and exhale it into the atmosphere.
Plants and Animals Die
* When plants and animals die, most of their bodies are decomposed, and carbon atoms are returned to the atmosphere as CO2.
* Some remains are not fully decomposed and end up as underground deposits (oil, coal, etc. = fossil fuels = carbon).
(N2) makes up 78% of the atmosphere.
Most living things cannot use atmospheric nitrogen to make amino acids and other nitrogen-containing compounds.
They depend on nitrogen-fixing bacteria to convert N2 into NH3 (NH4+).
Nitrogen
THE NITROGEN CYCLE
Nitrogen Fixation: Atmospheric nitrogen (N2) is converted into usable ammonia (NH3).
Nitrification: Ammonia is converted into nitrate by bacteria in the soil.
Ammonification: Decomposers convert organic nitrogen into ammonia (NH3) and ammonium (NH4+).
Denitrification: Bacteria convert nitrites, nitrates, and nitrous oxides back into molecular nitrogen (N2).
is important because it is how water reaches plants, animals, and us.
It also moves things like nutrients, pathogens, and sediment in and out of aquatic ecosystems.
water cycle
THE WATER CYCLE
Evaporation: The sun heats water, turning it into vapor that enters the air.
Condensation: Water vapor cools and condenses into water droplets, forming clouds.
Precipitation: Water falls back to the ground as rain, snow, sleet, or hail.
Runoff: Rainwater flows downhill, attempting to return to oceans, lakes, rivers, or other water sources.
is a biogeochemical process that involves the movement of phosphorus through the lithosphere, hydrosphere, and biosphere.
It is a very slow process, with weathering helping to wash phosphorus from rocks into the soil.
phosphorus cycle
THE PHOSPHORUS CYCLE
Weathering: Weathering processes help to wash phosphorus from rocks into the soil.
Absorption by Plants: Plants absorb phosphorus from the soil.
Absorption by Animals: Animals obtain phosphorus by eating plants or other animals.
Return to the Environment through Decomposition: Decomposers break down dead organisms, returning phosphorus to the soil.
An ______________ is a structural and functional unit of ecology where the living organisms interact with each other and the surrounding environment.
ecosystem
- It refers to the rate of biomass production.
Productivity
- It is the sequential process through which energy flows from one trophic level to another. The energy captured from the sun flows from producers to consumers and then to decomposers and finally back to the environment.
Energy flow
- It is the process of breakdown of dead organic material. The top-soil is the major site for decomposition.
Decomposition
- In an ecosystem nutrients are consumed and recycled back in various forms for the utilization by various organisms.
Nutrient cycling
A is an ecosystem that is found on land. In terrestrial ecosystems, organisms live in the soil and in the air. Examples of terrestrial ecosystems are forests, grasslands, tundra, and deserts.
terrestrial ecosystem
is an ecosystem where many organisms live together with the environment’s abiotic components. There are many different flora and fauna in this ecosystem. Forests are significant carbon sinks and participate in controlling and balancing the overall temperature of the Earth.
forest ecosystem
- Tropical evergreen forests are found mostly near the equator. They have sparse undergrowth interspersed with clearings.
Tropical evergreen forest
- Tropical deciduous forests are also called the monsoon forests and spread over the region receiving rainfall between 200 cm and 70 cm. Trees of this forest-type shed their leaves for about six to eight weeks in dry summer.
Tropical deciduous forest
- Temperate evergreen forests are found in the United States, Canada, Europe, and Asia, in areas that generally receive between 300 and 900 mm of rain per year and with seasonal temperature extremes ranging from -40 to 20 °C.
Temperate evergreen forest
- The average daily temperatures range between -30°C (-22°F) and 30°C (86°F) with a yearly average of 10°C (50°F). Hot summers and cold winters are typical in this biome. On average, this biome receives 750 to 1,500 millimeters (30 to 59 inches) of rain per year.
Temperate deciduous forest
- The taiga is a forest of the cold, subarctic region. The soil beneath the taiga often contains permafrost—a layer of permanently frozen soil. Coldness is the dominant climatic factor in taiga ecosystems, although a surprising diversity of climates exists.
Taiga
are referred to as those ecosystems where the number of trees is low. These ecosystems mainly consist of grasses, shrubs, and herbs. Grassland ecosystems are commonly situated in both the tropical and temperate regions globally; however, they have distinct variations.
Grassland ecosystems
- are grasslands that are located closer to the equator than prairies. Savannas can receive as much as 120 cm of rain per year. In addition to grass, scattered shrubs and small trees can grow in the savanna.
Savanna
are devoid of trees and are found in cold climates or where rainfall is scarce. These are covered with snow for most of the year. Tundra type of ecosystem is found in the Arctic or mountain tops. Because rainwater cannot soak into the permafrost, there are many shallow ponds and marshy areas of the tundra during the summer.
Tundra ecosystems
exist worldwide and cover about 17 percent of desert areas. These are areas where annual rainfall is usually measured less than 25 mm. Due to fewer trees and land of sand, sunlight intensifies in these ecosystems.
Desert ecosystems
TYPES OF DESERT ECOSYSTEM
- Sand desert
- Rock desert
- Stony desert
- Plateau desert
- Cold desert
is an ecosystem that is found in water. Aquatic ecosystems are home to a wide variety of plants and animals. The two main types of aquatic ecosystems are freshwater ecosystems and marine ecosystems.
aquatic ecosystem
The __________is an aquatic ecosystem that includes lakes, ponds, rivers, streams and wetlands. These have no salt content in contrast with the marine ecosystem.
freshwater ecosystem
- Water bodies that are moving slowly or are still in some places come under lentic. For example, ponds, lakes, pools, etc. Lakes are known as large water bodies and are surrounded by land.
Lentic Ecosystem
- Water bodies that are moving at a fast pace fall under a lotic. For example, streams and rivers. Animals adapt to the stream/river’s current (hooks and suckers to cling to rocks, streamline bodies). Few plants or algae can grow because of the strong currents. Animals rely on seeds and leaves to fall in the water as food.
Lotic Ecosystem
- Environments characterized by soils saturated with water for a long time fall under wetlands.
Wetland Ecosystem
are usually characterized by the presence of salt content. These ecosystems have a higher salt content than the freshwater ecosystem. Moreover, they are known as the largest type of ecosystem on Earth.
Marine ecosystems
VARIOUS HUMAN ACTIVITIES THAT AFFECT AN ECOSYSTEM
- Agriculture
- Deforestation
- Overpopulation and consumption
- Plastic production
- Emission of greenhouse gases and other greenhouse gases
- Destruction of the reefs
- Draining streams/rivers and destruction of critical freshwater aquifer recharge areas (water pollution)
- Overhunting and overexploitation
- Invasive species
commonly known as mahogany
Swietenia macrophylla
commonly known as The cane toad frog
Rhinella marina
An interdisciplinary field of research that seeks to understand the natural world and our relationship to it.
One of the most important properties of living things is that their abundances change over time and space.
ENVIRONMENTAL SCIENCE
THE HUMAN POPULATION OVER TIME
Since we emerged as our own species some 200,000 years ago, we have grown from a few thousands individuals to over 7 billion!
The time it takes our population to double has decreased sharply.
It only has taken about 12 years to go from 6-7 billion people.
We are projected to hit 9 billion near the year 2050.
Estimates say stabilization around 2100. (10.5 billion)
From the first evolution of humans to the beginning of agriculture.
Population density: About 1 person per 130-260 km^2 in the most habitable areas.
Total human population: As low as one-quarter million less than the population of modern small cities.
Average rate of growth: The annual rate of increase is less than 0.00011% per year.
HUNTERS AND GATHERERS
Beginning sometime between 9000 B.C. and 6000 B.C. and lasting until approximately the 16th century.
Population density: Human population increased greatly, about 1 or 2 people/km^2 or more.
Total human population: About 100 million by A.D. 1 and 500 million by A.D. 1600.
Average rate of growth: Perhaps about 0.03% which was high enough to increase the population.
EARLY PRE-INDUSTRIAL AGRICULTURE
Beginning in the 16th century
Total human population: About 900 million in 1800, almost doubling in the next century and doubling again (to 3 billion) by 1960.
Average rate of growth: By 1600, about 0.1% per year, with rate increases of about 0.1% every 50 years until 1950.
THE MACHINE AGE
Beginning in the mid-20th century
Total human population: Reaching and exceeding 6.6 billion.
Average rate of growth: The growth rate of the human population reached 2% in the middle of the 20th century and has declined to 1.2%
THE MODERN ERA
- is the general study of population changes.
Population dynamic
- is a group of individuals of the same species living in the same area or interbreeding and sharing genetic information.
Population
- is all individuals that are capable of interbreeding, and so a species is composed of one or more populations.
Species
- is the statistical study of human populations, and people who study the human population include demographers.
Demography
Factors that drive population growth include:
- Birth rate
- Death rate
- Immigration
- Emigration
Human _____________ is stated as the number of individuals born per year per 1000 in the population.
The population logically escalates if the number of births is more than the number of deaths at any particular time or if the death rate is less or slower in respect to the birth rate.
The formula for calculating crude ___________ is:
Crude Birth Rate (CBR) = (Number of births within a year/Total mid-year population) × 1000
The current birth rate for the Philippines in 2022 is 19.778 births per 1000 people, a 1% decline from 2021.
Birth rate
A crucial reason affecting the growth of the population is the death, or mortality rate.
As the birth of new individuals escalates the population size, deaths decline it. The issues that affect the mortality rate consist of the accessibility and affordability of quality health care and daily life practices.
The formula for calculating Crude Death Rate is:
Crude Death Rate (CDR) = (Number of deaths within a year/Total mid-year population)× 1000
Death rate
(moving into the place/country) is the movement of individuals into a population from other areas.
Immigrants contribute to population growth because of both their own numbers and their above-average fertility. Most of those who immigrate are working-age adults.
Immigration
(exiting from a place/country) is the movement of individuals out of a population.
A number of factors, such as running away from war, searching and finding good education, pursuing a career, searching new jobs or union with family members, results in emigration.
When an individual emigrates from a nation, its population declines gradually.
Emigration
attract people towards a certain place/country. Example of pull factors include; better job opportunities, social securities, better health facilities and improved education systems etc.
Pull factors
force people to leave the place/country. Examples of push factors include; lack of social harmony and peace, increased conflict, war, poor education systems, poor job opportunities, lack of adequate resources etc.
Push factors
- An estimate of the average number of children that each woman in a population will bear throughout her childbearing years.
Total fertility rate (TFR)
- The total fertility rate required to offset the average number of deaths in a population in order to maintain the current population size.
- tends to be higher in developing countries because mortality among young people tends to be higher.
Replacement-level fertility
- The average number of years that an infant born in a particular year in a particular country can be expected to live, given the current average life span and death rate in that country.
Life expectancy
- The number of deaths of children under 1 year of age per 1,000 live births.
Infant mortality
- The number of deaths of children under age 5 per 1,000 live births.
Child mortality
- A visual representation of the number of individuals within specific age groups for a country, typically expressed for males and females.
- describe how populations are distributes across age ranges
Age structure diagram
- An age structure diagram that is widest at the bottom and smallest at the top, typical of developing countries.
Population pyramid
- Continued population growth after growth reduction measures have been implemented.
Population momentum
occurs in a population that has many young people and a high death rate at each age—and therefore a high birth rate, characteristic of a rapidly growing population and also of a population with a relatively short average lifetime.
The pyramid age structure
occurs where the birth rate and death rate are low and a high percentage of the population is elderly.
A column shape
occurs if some event in the past caused a high birth rate or death rate for some age group but not others.
A bulge
occurs when a population has more older than younger people.
An inverted pyramid
- studied human population growth and said was growing faster than Earth’s resources
Thomas Malthus (late 1700’s)
Malthus examined the relationship between population growth and resources in one of his works. He then proposed the Malthusian theory of population where he said that the population grows exponentially and the food supply grows arithmetically and that a balance between the two can be established through positive and preventive checks.
MALTHUSIAN THEORY OF POPULATION
HUMAN IMPACTS ON ECOSYSTEM
Modern scientists use there observations and predictions when describing ecosystem’s carrying capacity
Current human population is about 7 billion.
Not sure what the limit (carrying capacity) is for size of human population.
Maximum number of individuals an ecosystem can support
Carrying Capacity
include coal, natural gas, oil, and nuclear energy. Once these resources are used up, they cannot be replaced, which is a major problem for humanity as we are currently dependent on them to supply most of our energy needs.
Non-renewable resources
- resources that can be used up or can replenish themselves over time (e.g. wind energy, solar, lumber, etc.)
Renewable resources
INDUSTRIAL REVOLUTION
What happens during the Industrial Revolution?
- Energy: coal and steam replace wind, water, human and animal labor.
- Organization: factories over cottage industries
- Rural agriculture declines, urban manufacturing increases
- Transportation: trains, automobiles replace animals, watercraft
The effects of Industrial Revolution cannot be understated. It changed how and where people lived as well as their environments.
People could no longer get work in rural areas and were forced to move to cities to find work in factories.
Many working class women joined the workforce to support their families.
Rapid urbanization resulted in dirty, crowded cities with poor sanitation that encouraged the spread of disease.
Skilled workers, such as weavers, were replaced by machines that could do the work faster.
New inventions allowed for mass production of goods like cloth.
Factory conditions were poor; work was often dangerous, and pay was often low. Factory owners became rich, while the poor working class struggled to make enough money for basic necessities.
Environmental pollution increased.
EFFECTS OF INDUSTRIAL REVOLUTION
- The change from a farming economy to a machine economy. The “modernizing” of a place.
- is a transformation away from an agricultural- or resource-based economy, toward an economy based on mechanized manufacturing.
- is usually associated with a greater average income and improved living standards.
Industrialization
- Making products with employees as quickly as possible.
- The system of manufacturing that began in the 18th century with the development of the power loom and the steam engine and is based on concentration of industry into large establishments.
FACTORY SYSTEM
WHY DID INDUSTRIALIZATION BEGIN IN ENGLAND FIRST?
- Markets: England had many overseas colonies (markets)
- Population:
skilled workers
wealthy entrepreneurs
vast number of laborers (workers) - Agricultural Changes:
Enclosure Acts tenant farmers forced off the farms; moved to cities (urban areas) to find work in factories. - Natural Resources:
coal, iron ore
good harbors, canals
colonies had raw materials - lumber, cotton - Government:
stable & unified country; Parliament; Limited Monarchy
fair taxes & solid banking system - Other Factors:
Island - isolated; had not been through devastating wars
capitalist economy
encouraged science and research
pitted the young United States in a war against Great Britain, from whom the American colonies had won their independence in 1783.
When the British interfered with American trade, the Americans had to create their own factories instead of relying on Europe
The War of 1812
HOW DID INDUSTRIALIZATION LEAD TO POLLUTION?
These factors led to the depletion of natural resources. Factories would spew smog and soot into the air and release pollutants and chemicals directly into rivers and streams, resulting in increased air and water pollution. The Industrial Revolution saw an increased use of fossil fuels, including coal.
- Early factories polluted a lot.
- Cities in the 1800s were incredibly polluted.
- Living conditions were usually very bad.
, lethal SMOG that covered the city of London for five days (December 5–9) in 1952, caused by a combination of industrial pollution and high-pressure weather conditions.
Great Smog of London
Emission of carbon dioxide, methane and other waste products that pollute the air and are believed to contribute to global climate change. Global cement industry contribute 5% of global carbon dioxide emission.
CONSTRUCTION INDUSTRY
This results in a large amount of hazardous household waste that is often irresponsibly discarded in trash. When electronics are not recycled properly, the raw materials them leech toxic chemicals into the ground, spoiling both water and food supply for decades, at least.
ELECTRONICS INDUSTRY
Climate changes across the global fertilizers consists of substances and chemicals like methane, carbon dioxide, ammonia and nitrogen, the emission of which has contributed to a great extent in the quantity of greenhouse gases present in the environment.
This in turn is leading to global warming and weather changes.
CHEMICALS INDUSTRY
During the production of textiles a large amount of energy is used to power the factories. This then creates more pollution such as carbon dioxide.
Dyeing, bleaching or adding finishes to fabrics often involve using highly toxic chemicals. Water used in process is pumped into rivers and sewage offering wildlife and humans. Growing raw materials such as cotton requires large amounts of pesticides. These pesticides are harmful and often affect birds, the water system and insects.
TEXTILES INDUSTRY
Water pollution, Loss of Biodiversity, Soil erosion and pollution, Formation of sink holes.
MINING INDUSTRY
Food accounts for over a quarter (26%) of global gas emissions.
Half of the world’s habitable (ice and desert free) land is used for agriculture.
FOOD AND BEVERAGE INDUSTRY
HOW DID INDUSTRIALIZATION LEAD TO URBANIZATION?
People started to move close to their factory jobs. This movement led to bigger cities. Urbanization is an effect of Industrialization.
Industrialization is the process that takes an agricultural economy and transforms it into a manufacturing one. Mass production and assembly lines replace manual and specialized laborers. The process has historically led to urbanization by creating economic growth and job opportunities that draw people to cities.
is the process through which cities grow, and higher and higher percentages of the population comes to live in the city.
Urbanization
- is the region surrounding a city.
- Most inhabitants of urban areas have nonagricultural jobs.
- are very developed, meaning there is a density of human structures such as houses, commercial buildings, roads, bridges, and railways.
- can refer to towns, cities, and suburbs.
urban area
URBAN vs RURAL
Urban
* High Population Density
* More than 2500 people
* City
Rural
* Low Population Density
* Less than 2500 people
* Countryside
* Agricultural
- Urban growth is defined as the rate at which the population of an urban area increases. This result from urbanization which is the movement of people from rural areas to urban areas.
Urban Growth
- Urban sprawl can be defined as urban development with low-density housing, both residential and commercial, segregated land-use, high level of automobile use combined with lack of public transport, which is in high demand for land (Johnson, 2001).
Urban Sprawl
- is a place where people live just outside of a city or town. There are lots of houses in suburban areas, but not as many other buildings as urban areas—maybe just one or two small shops or stores.
Suburb
PULL vs PUSH FACTORS
Pull factors – better jobs, cheaper housing, more resources, better education.
Push factors – poor education, medical, religious, cultural
An occurs when a city experiences much warmer temperatures than nearby rural areas. The difference in temperature between urban and less-developed rural areas has to do with how well the surfaces in each environment absorb and hold heat.
- occurs when a city experiences much warmer temperatures than nearby rural areas.
urban heat island
IMPACTS OF URBANIZATION
Air Quality- Human activities release a wide range of emissions into the environment including carbon dioxide, carbon monoxide, ozone, sulfur oxides, nitrogen oxides, lead, and many other pollutants.
Changes in Patterns of Precipitation- Cities often receive more rain than the surrounding countryside since dust can provoke the condensation of water vapor into rain droplets.
Pollution - Pollutants are often dispersed across cities or concentrated in industrial areas or waste sites. Lead- based paint used on roads and highways and on buildings is one such example of a widely dispersed pollutant that found its way into soil.
Erosion and other changes in land quality- Rapid development can result in very high levels of erosion and sedimentation in river channels.
Degraded Water Quality- The water quality has degraded with time due to urbanization that ultimately leads to increased sedimentation there by also increasing the pollutant in run-off.
Flow of Water through Streams - Higher, faster peak flows change streams channels that have evolved over centuries under natural conditions. Flooding can be a major problem as cities grow and stream channels attempt to keep up with these changes.
Destruction of Habitats- There is also complete eradication of habitats as an outcome of urbanization and native species are pushed out of cities.
Creation of New Habitats- New habitats are also created for some native and non-native species. Cities also create habitats for some species considered pests, such as pigeons, sparrows, rats, mice, flies and mosquitoes. Urbanization has, for example, eliminated many bat colonies in caves, but has provided sites such as bridges for these species to nest.
