Human IMPACTHuman IMPACT

Objectives:Objectives:

Explain the consequences of humans and consumption on Earth’s Spheres

Humans and Nature: An OverviewHumans and Nature: An Overview

““The environmental crisis is an outward manifestation of a The environmental crisis is an outward manifestation of a crisis of mind and spirit. There could be no greater crisis of mind and spirit. There could be no greater misconception of its meaning than to believe it is concerned misconception of its meaning than to believe it is concerned only with endangered wildlife, human-made ugliness, and only with endangered wildlife, human-made ugliness, and pollution. These are part of it, but more importantly, the pollution. These are part of it, but more importantly, the crisis is concerned with the kind of creatures we are and crisis is concerned with the kind of creatures we are and what we must become in order to survive.what we must become in order to survive.””

~ Lynton K. ~ Lynton K. CaldwellCaldwell

Diagram makes it clear that environmental science is multidisciplinary and interdisciplinary.

That is, “it takes all kinds” of observations and inputs to “do” environmental science.

If you really got a hold of anything in the Universe, you find out that it’s hitched to everything else.—John Muir, Founder, Sierra Club

The Human Impact Problem?The Human Impact Problem?

Several themes—recurring and inter-connected Several themes—recurring and inter-connected Human population x demand for resources = root Human population x demand for resources = root

problem. problem. (Problem for each other as individuals, communities, (Problem for each other as individuals, communities,

nations; for the rest of the ecosphere.)nations; for the rest of the ecosphere.) The impact of environment on human healthThe impact of environment on human health

Assignment – Cats of BorneoAssignment – Cats of Borneo

Complete Complete ““Cats of BorneoCats of Borneo”” activity activity You will receive an envelope with 13 statements You will receive an envelope with 13 statements

which are numbered.which are numbered. Your job as a group is to order them by event Your job as a group is to order them by event

(not numerically!)(not numerically!)

Based on a Based on a true story

A simple exercise to get you thinking about the interconnectedness of man, environment and how one decision can cause a domino effect in the scheme of environment!

Change in the BiosphereChange in the Biosphere= change in the environment= change in the environment

Changes in the Lithosphere

•Leads to local and global health issues

•Competition for resources

•Destruction of habitats and upheaval of human populous

Changes in the AtmosphereChanges in the Atmosphere

Increased global Increased global temperatures – temperatures – greenhouse effect? greenhouse effect? Normal or enhanced?Normal or enhanced?

Loss of ozone due to Loss of ozone due to chlorfluorocarbons chlorfluorocarbons (CFCs)(CFCs)

Increase of natural Increase of natural gases (Sulfur and gases (Sulfur and COCO22) due to volcanic ) due to volcanic eruptionseruptions

The Great American HypocriteThe Great American Hypocrite

Aquatic and Aquatic and marine marine

resources—resources—long-long-

neglected, neglected, over-over-

exploited, exploited, directly and directly and indirectly* indirectly* impacted.impacted.

*remember, water flows downhill—The 1st Law of Ecology

Changes in the hydrosphere

What characteristics of Earth make life possible?What characteristics of Earth make life possible?

WaterWater AirAir (nitrogen, oxygen, (nitrogen, oxygen,

carbon dioxide and carbon dioxide and water vapor)water vapor)

SoilSoil SunSun – driving force – driving force

behind all life behind all life processes.processes.

Biosphere (Ecosphere)Biosphere (Ecosphere)

All the parts of Earth that All the parts of Earth that support and contain life.support and contain life.

Reaches from the floor of Reaches from the floor of the ocean to the tops of the ocean to the tops of the mountains.the mountains.

Approximately 20 km Approximately 20 km (12.4 mi) thick.(12.4 mi) thick.

If the earth were an apple, the If the earth were an apple, the ecosphere would be no thicker ecosphere would be no thicker than the applethan the apple’’s skin!s skin!

EnvironmentEnvironment

Everything that surrounds a particular organism.

EcologyEcology

Study of the interaction between Study of the interaction between organisms and their environment, organisms and their environment, composed of abiotic (NON-Living) and composed of abiotic (NON-Living) and biotic (living) factors biotic (living) factors

Ecosystem StructureEcosystem Structure

Food Web – a network of food chains Food Web – a network of food chains representing the feeding relationships representing the feeding relationships among the organisms in an ecosystem among the organisms in an ecosystem (complicated).(complicated).

Biological MagnificationBiological Magnification

The increasing The increasing concentration of a concentration of a pollutant in organisms at pollutant in organisms at higher trophic levels in a higher trophic levels in a food web.food web.

Ex. In 1972 the US Ex. In 1972 the US banned the use of DDT. banned the use of DDT. By 1991 bald eagle By 1991 bald eagle population rebounded 4X.population rebounded 4X.

Diversity and StabilityDiversity and Stability

A deciduous forest is an example of a A deciduous forest is an example of a stable ecosystem that has a food web with stable ecosystem that has a food web with many links.many links.

A small disturbance has a small effect on A small disturbance has a small effect on a deciduous forest. Conversely, a tundra a deciduous forest. Conversely, a tundra has few links in the web, therefore a small has few links in the web, therefore a small disturbance can have a larger impact.disturbance can have a larger impact.

Energy in the EcosystemEnergy in the Ecosystem

The ultimate and only significant source The ultimate and only significant source of energy in most ecosystems is that of energy in most ecosystems is that radiated by the sun. radiated by the sun.

This energy is the driving force of This energy is the driving force of photosynthesis. Of the total sunlight photosynthesis. Of the total sunlight received on the earth, only 20-25% is received on the earth, only 20-25% is available for photosynthesis because available for photosynthesis because only the longer wavelengths are used in only the longer wavelengths are used in photosynthesis. photosynthesis.

Key players in ECOLOGY: Key players in ECOLOGY: Producers, Consumers and DecomposersProducers, Consumers and Decomposers

All biomes (and ecosystems within All biomes (and ecosystems within biomes) contain three different kinds of biomes) contain three different kinds of living things: living things:

1) Decomposers1) Decomposers

2) Producers 2) Producers

3) Consumers3) Consumers

  

Producers (Autotrophs)Producers (Autotrophs)

Organisms that make Organisms that make their own food from their own food from inorganic molecules inorganic molecules and energy.and energy.

EX. - PlantsEX. - Plants

Consumers (Heterotrophs)Consumers (Heterotrophs)

1) Cannot produce their own food 1) Cannot produce their own food (animals, humans- any living thing (animals, humans- any living thing that does not have chlorophyll)that does not have chlorophyll)

2) Must eat other organisms (plants 2) Must eat other organisms (plants and/or animals) to get their energy and/or animals) to get their energy and food. and food.

EX: animals, fungi, protists and bacteriaEX: animals, fungi, protists and bacteria

Bacteria and fungi that consume the bodies of Bacteria and fungi that consume the bodies of dead organisms and other organic wastes.dead organisms and other organic wastes.

Decomposers complete the cycle of matter in Decomposers complete the cycle of matter in the ecosystem.the ecosystem.

Trophic LevelTrophic Level

What scientists What scientists call the different call the different feeding levels of feeding levels of organisms in a organisms in a ecosystem.ecosystem.

From the root From the root ““trophtroph”” – – meaning to feed meaning to feed or nourish.or nourish.

Trophic Levels Trophic Levels

Number pyramid Number pyramid the higher one the higher one

moves, each moves, each consecutive layer or consecutive layer or level contains fewer level contains fewer organisms than the organisms than the level below it. level below it.

BiomassBiomass The total amount of The total amount of

organic matter present organic matter present in a trophic level.in a trophic level.

Potentially food for the Potentially food for the next trophic level.next trophic level.

As organisms do work, As organisms do work, they use energy, and they use energy, and must continue to take must continue to take in additional fuel to in additional fuel to continue doing work continue doing work

Cycles of MatterCycles of Matter

Chemical composition of human bodyChemical composition of human body Water CycleWater Cycle Carbon CycleCarbon Cycle Nitrogen CycleNitrogen Cycle

Water Cycle – Water Cycle – All the water on Earth which is All the water on Earth which is continually cycled from hydrosphere to atmosphere and continually cycled from hydrosphere to atmosphere and

lithospherelithosphere

Carbon CycleCarbon Cycle

Plants use COPlants use CO22 and and

sunlight to make sunlight to make sugars and starches sugars and starches during photosynthesisduring photosynthesis

Nitrogen CycleNitrogen Cycle

Organisms require nitrogen in order to Organisms require nitrogen in order to make amino acids, the building blocks of make amino acids, the building blocks of proteins.proteins.

80% of Earth's atmosphere is made up of 80% of Earth's atmosphere is made up of nitrogen in its gas phase. nitrogen in its gas phase.

Plants take up the nitrates and convert Plants take up the nitrates and convert them to proteins that then travel up the them to proteins that then travel up the food chain through herbivores and food chain through herbivores and carnivores. When organisms excrete carnivores. When organisms excrete waste, the nitrogen is released back into waste, the nitrogen is released back into the environment. the environment.

Competitive ExclusionCompetitive Exclusion

The extinction of a population due to direct The extinction of a population due to direct competition with another species for a resource.competition with another species for a resource.

If two species try to share the same niche in the If two species try to share the same niche in the same habitat, they will compete for resources.same habitat, they will compete for resources.

If one is better than the other, one will have to If one is better than the other, one will have to move to another area or extinction may occur.move to another area or extinction may occur.

Population GrowthPopulation Growth

Exponential Growth – Exponential Growth – population growth in population growth in which the rate of which the rate of growth in each growth in each generation is a generation is a multiple of the multiple of the previous generation.previous generation.

City Lights from Space

Geospatial demographers, such as Deborah Balk, use satellite images of the Earth at night to estimate population densities.

Human Population on the 50th Earth DayHuman Population on the 50th Earth Day

The following is from an insert to a solicitation The following is from an insert to a solicitation letter from the group letter from the group Zero Population Growth. .

In the seconds it takes you to read this sentence, 24 people will be added to the Earth’s population.

 Before you’ve finished this letter, that number will reach 1,000. Within an hour ... 11,000. By day’s end ... 260,000.

 Before you go to bed two nights from now, the net growth in human numbers will be enough to fill a city the size of San Francisco.

 It took four million years for humanity to reach the 2 billion mark. Only 30 years to add a third billion. And now we’re increasing by 95 million every single year.

 No wonder they call it the human race.

Carrying CapacityCarrying Capacity

The number of individuals of a species The number of individuals of a species that can be supported by an ecosystem.that can be supported by an ecosystem.

As population grows, it takes more from its As population grows, it takes more from its habitat.habitat.

Resources such as food and living space Resources such as food and living space become scarce.become scarce.

As resources become scarce, individuals As resources become scarce, individuals begin to compete.begin to compete.

Managing Land UseManaging Land Use

Ecological SuccessionEcological Succession

Change is a fact of life!Change is a fact of life! Living things have evolved in response to Living things have evolved in response to

change.change. As an environment changes, the As an environment changes, the

community changes with it.community changes with it. In many cases, different communities In many cases, different communities

follow one another in a definite pattern.follow one another in a definite pattern.

Evolution and AdaptationEvolution and Adaptation

Ecosystems change Ecosystems change over time and over time and changes in the changes in the environment affect environment affect the evolution of the evolution of populations.populations.

InterdependenceInterdependence

Health depends on Health depends on resources.resources.

Good health depends Good health depends on accessibility to on accessibility to sustainable sustainable resources.resources.

InterdependenceInterdependence

Bad health results Bad health results from inaccessibility to from inaccessibility to sustainable resources sustainable resources or exposure to a or exposure to a hazard.hazard.

Both exist in the Both exist in the environment.environment.

Therefore, quality of Therefore, quality of health depends on health depends on the environment.the environment.

Community Action and the Community Action and the EnvironmentEnvironment

What are the environmental problems that What are the environmental problems that we face as communities, as states, as a we face as communities, as states, as a country, and as part of the global country, and as part of the global communitycommunity? ?

How many environmental problems are How many environmental problems are you aware of? you aware of?

Human Population and Human Population and Carrying CapacityCarrying Capacity

What impact does an ever increasing What impact does an ever increasing population have on global health issues?population have on global health issues?

What characteristics of life allow it to influence the What characteristics of life allow it to influence the

environment on the global scale?environment on the global scale?

1.1. Life spreads exponentiallyLife spreads exponentially

7 BILLION

The environmental problems we face – population growth, wasteful use of resources, destruction and degradation of wildlife habitats, extinction of plants and animals, poverty, and pollution – are interconnected and are growing exponentially.

More People = More CompetitionMore People = More Competition According to the United According to the United

Nations, world population Nations, world population reached 7 billion on reached 7 billion on October 31, 2011October 31, 2011

According to the most According to the most recent estimates, world recent estimates, world population is expected to population is expected to reach 8 billion people in reach 8 billion people in the spring of 2024.the spring of 2024.

What matters is that we What matters is that we are competing for are competing for essential resourcesessential resources

Which leads to global environmental Which leads to global environmental problems like….problems like….

Competition Competition Resource DepletionResource Depletion PollutionPollution Risk, Toxicology and Human HealthRisk, Toxicology and Human Health Climate, Global Warming and Ozone Climate, Global Warming and Ozone

DepletionDepletion Water resources and water qualityWater resources and water quality Solid and hazardous waste disposalSolid and hazardous waste disposal

Global Warming?Global Warming?

TRUE or NOT???TRUE or NOT??? Regardless of whether you believe that Regardless of whether you believe that

man is enhancing global warming or we man is enhancing global warming or we are just in a are just in a ““normalnormal”” warming period – the warming period – the ensuing environmental changes will have ensuing environmental changes will have an impact on both animals and humans!an impact on both animals and humans!

60 Minutes 60 Minutes Video on evidence in Antarticaon evidence in Antartica

What impact will climate change (global What impact will climate change (global warming) have on the human species?warming) have on the human species?

Food shortagesFood shortages Loss of fresh waterLoss of fresh water Increase in diseaseIncrease in disease

6o of Change!

Climate Change and FoodClimate Change and Food

Climate Change and Food Security: Out of the Mouths of Babes

Now that scientists agree? What do Now that scientists agree? What do we do…..we do…..

How to feed the world in 2050: actions How to feed the world in 2050: actions in a changing climatein a changing climate

ClimateClimateand and

Human Human HealthHuman Human Health

What impact will global warming have on What impact will global warming have on our human health?our human health?

Think about disease and the spread of Think about disease and the spread of disease – can you make a connection disease – can you make a connection between climate change and the spread between climate change and the spread of diseases?of diseases?

Kinds of health impacts resulting Kinds of health impacts resulting from climate change:from climate change:

Direct- result from Direct- result from weather extremes.weather extremes.

Consequences from Consequences from ecological disruption.ecological disruption.

Consequences Consequences resulting from resulting from climate-induced climate-induced economic disruption, economic disruption, e.g. traumatic, e.g. traumatic, infectious, nutritional, infectious, nutritional, psychologicalpsychological

Social factors affecting healthSocial factors affecting health

Population densityPopulation density Level of economic development of the Level of economic development of the

countrycountry Food availabilityFood availability Pre-existing health statusPre-existing health status Availability of health careAvailability of health care

Human Population DynamicsHuman Population Dynamics

:28

What have we learned about the impact of population on:

•Resources?

•Global Health?

•Global Warming?