Chapter 6
Humans in the
Biosphere
6.1 A Changing Landscape
 How has humans impacted landscapes?
 Agriculture
 Development
 Industries
 In order to preserve nature, in Hawaii for every tree cut
down, you must plant two.
 You cannot fish during spawning season.
 What is Oxford and other parts of Southern Chester
County known for?
 Farming
 What is Kennett Square known for?
 Mushroom farms
Farming
 Agriculture: Farming
 One of the most important inventions in the world.
 Before farming, Native Americans lived off the land and
refused to plant crops.
 Monoculture:
 Practice of clearing large areas of land to plant a single
highly productive crop year after year.
Monoculture
Development
 Urban cities have become over crowded.
 Philadelphia.
 More and more people are moving out of the city, and
moving to the suburbs. (Delaware county and now Chester
County)
 Think of Oxford 10 years ago. No Walmart!
Sustainable Development
 Renewable resources:
 Can be produced or replaced by a healthy ecosystem.
 Example:
 Trees and plants
 Nonrenewable resources:
 Natural processes cannot replenish them within a
reasonable amount of time. (could be gone forever)
 Example:
 Coals, oil, and natural gas.
6.2 Using Resources Wisely
 In the 1930’s, poorly managed farms and severe
drought badly damaged fertile soil.
 The area eventually turned into desert.
 Thousands of people lost their jobs.
 Healthy soil supports both agriculture and forestry.
 Desertification:
 Dry climates, over farming, overgrazing, seasonal
drought, and climate change turns farmland into desert.
 What is happening to our forests across the world?
 Deforestation
Deforestation
 Deforestation:
 Loss of forests.
 Can lead to severe erosion.
 Can change local soils and microclimates.
 Can prevent tree growth.
Freshwater Resources
 Humans depend on fresh water and freshwater
ecosystems for goods and services.
 Drinking water, industry, transportation, energy, and
waste disposal are all very important.
 Fresh water can be damaged by pollutants.
 Pollutants:
 A harmful material that can enter the biosphere.
Oil Spills
Other effects of Pollution
 Who here eats fish?
 Why do some people not eat fish anymore?
 High amounts of mercury.
Bio Magnification
 If a small fish has mercury in its system and gets eaten by a
bigger fish… the bigger fish now has a higher amount of
mercury in its system.
 The amount of mercury increases as the small fish gets
consumed and moves up a food chain.
 Biomagnication:
 Occurs if a pollutant, is picked up by an organism and is not
broken down or eliminated from its body.
Atmospheric Resources
 Atmosphere is important for oxygen, regulating global
temperature, and absorbs harmful radiation.
 Common forms of air pollution are
 Smog
 Acid rain
 Greenhouse gases
 Smog:
 A gray-brown haze formed by chemical reactions
among pollutants released into the air by industrial
processes and automobiles.
 In the 2008 Summer Olympics in Beijing China, there
was a strong concern for health due to intense smog.
Atmospheric Resources
 When we burn fossil fuels in our factories and homes,
we release nitrogen and sulfur compounds.
 Eventually forms acid rain.
 Acid rain:
 Airborne acid.
Air Quality and Sustainability
 Automobile emission standards and clean air
regulations have improved air quality in some regions.
6.3 Biodiversity
 What is biodiversity?
 Bio-living
 Diversity- variation
 Biodiversity:
 Total of all the genetically based variation in all
organisms in the biosphere.
Types of Biodiversity
 Ecosystem diversity:
 Variety of habitats, communities and ecological
processes.
 Species diversity:
 The number of different species in the biosphere or in a
particular area.
 Genetic diversity:
 Sum total of all different forms of genetic information
carried by a particular species.
Valuing Biodiversity
 Benefits society by medicine, agriculture, and the
provision of ecosystems goods and services.
 Medicine such as antibiotics, penicillin, and to treat
heat disease are found in plants.
 Plants help farming with genetic engineering.
 In ecosystems, variety of species help sustain
productivity and value in humans.
Threats to Biodiversity
 Scientists estimate that over 99% of the species that
have ever lived are new extinct.
Threats to Biodiversity
 1. Habitat fragmentation:
 Splits ecosystems into pieces.
Threats to Biodiversity
 2. Hunting and the Demand for Wildlife Products
 In the 1800s, hunting wiped out the Carolina parakeet
and passenger pigeon.
Threats to Biodiversity
 Recently in 2015, the last male White Rhino was
guarded by marines 24/7.
Threats to Biodiversity
 3. Introduced Species:
 Organisms that are introduced to a new habitat.
 These introduces species can outcompete native
species and destroy the local area.
 Ranches and farmers lose $120 million dollars to
certain pests.
Threats to Biodiversity
 4. Pollution
 Many pollutants threaten biodiversity. DDT prevents
birds from laying healthy eggs.
 Increase carbon dioxide making chemicals more acidic.
Threats to Biodiversity
 5. Climate Change
 Major threat to biodiversity.
 Organisms are adapted to live in certain areas.
 If conditions change the adapted organisms are more
likely to die off.
Conserving Biodiversity
 1. Protecting Individual Species
 2. Preserving Habitats and Ecosystems
 Ecological hotspot:
 Place where significant number of species and habitats
are endanger of extinction.
 3. Considering Local Interests
6.4 Meeting Ecological
Challenges
 Ecological footprints:
 The total area of functioning land and water
ecosystems needed both to provide the resources an
individual or population uses and to absorb and make
harmless the wastes that individual or population
generates.
 Ecologists use footprint calculations to estimate the
biosphere’s carrying capacity for humans.
 Which countries have the highest ecological footprint?
 The united states has an ecological footprint over four
times larger than the global average.
Ecology in Action
 Ecology can help us sustain our future by…
 1. Recognizing a problem in the environment.
 2. Researching the problem to determine its cause.
 3. Using scientific understanding to change our
behavior, and make a positive impact.
Different case studies pg 175179
 What are these?
 Aquaculture:
 Farming of aquatic animals.
 What is happening to the Earth’s average temperature?
 Increasing!
 What do plants take in for photosynthesis?
 Co2
 What is happening to our plants.
 They are being destroyed.
 Global warming:
 Increase in average temperature
 In roughly a million years from now the Earth will explode.