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Chapter 6: Humans in the Biosphere. Changing Landscapes. Effects of Human Activity. Agriculture Monoculture Idea of planting a single crop year after year Problems: Pollutes the soil and water (How?) Wastes fossil fuels Drains the soil of nutrients . Effects of Human Activity. Housing
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Chapter 6: Humans in the Biosphere Changing Landscapes
Effects of Human Activity • Agriculture • Monoculture • Idea of planting a single crop year after year • Problems: • Pollutes the soil and water (How?) • Wastes fossil fuels • Drains the soil of nutrients
Effects of Human Activity • Housing • Problems: • Increase in population density leads to more waste • If not treated properly, land, air, and water pollution • Divides environment • Destroys animals habitats
Effects of Human activity • Industrial Growth • Problems: • Depletion of fossil fuels • Needed for machines to conduct work • Environmental harms • Dumping of toxic waste
Sustainable Development • Renewable Resource • Resources that can be replaced or produced in a healthy ecosystem • Must be done in reasonable amount of time • Examples? • Nonrenewable Resource • Resources that can’t be produced by a natural process in a reasonable amount of time • Examples?
Chapter 6: humans in the biosphere Using Resources Wisely
Soil Resources • Erosion • Desertification • Losing soil due to over farming, drought, or climate change • Example • Dust Bowl 1930’s • All 3 problems occurred at the same time • Soil could be found hundreds of miles off coast of New York • Deforestation • Destruction of forests • Problems: • Tree roots help hold soil together and nutrients • Removing trees causes these things to be lost
Soil resources • Methods of sustainability • 1. Leave behind roots and stems in soil • 2. Crop rotations • Planting different crops each season • Helps maintain nutrient levels in soil • 3. Contour Plowing • Plant crops across the slopes of land instead of down the slope • Reduces the amount of water runoff • 4. Cut down mature trees only
Freshwater resources • Water Pollution • Point source • Exact location of water pollution • Caused by an oil spill or factory dumping • Non-point source • Water pollution that occurs due to dumping in a different location • Caused by runoff into water sources • Biological Magnification • Can be linked to snowball effect • As you move up through the trophic levels, higher concentrations of substances can be found in organisms
Atmospheric resources • Air Pollution • Smog • Chemical reaction of air pollutants • Result from car exhausts and factory chemicals • Acid Rain • Results from air pollution caught up in clouds • Rain caused destruction to plants • Pollutants can ruin the soil as well • Greenhouse Gases • Gases occur naturally • Pollution causes for increase of them which causes higher temperatures • Particulates: Ash and Dust (Harmful if swallowed)
Chapter 6: Humans in the biosphere Biodiversity
Types of Biodiversity • Biodiversity: Total variety of organisms in the biosphere • 1. Ecosystem diversity • Different ecosystems in the biosphere • Can be thought of as the different biomes • 2. Species diversity • Number of species on the planet • 1.8 million discovered already • 30 million undiscovered • 3. Genetic diversity • All forms of genetic information in each species
Uses of biodiversity • Medicine • Used to treat disease • A large number of plants in rain forest have been tested against types of cancer • Agriculture • Domestic plants have wild relatives • We can use genes from each plant to create pest resistant plants or better plants
Threats to biodiversity • Altered Habitats • Fragmentation • Splitting of an ecosystem • When cities built in ecosystems • Creates competition • Can lead to extinction of species • Hunting • Over hunting can lead to endangered species • Endangered species struggle to do their job in environment
Threats to biodiversity • Introduction of new species • Bringing in of a new species can create unbalance • Leads to other species leaving and destruction of ecosystem • Pollution • Lowers biodiversity • Poor conditions leads to lower birthrates • Climate Change • Species adapted to a specific climate and environment • When climate changes, survival becomes difficult
conservation • Zoos • Allows for humans to save species • Introducing captive breeding • Enlarge population through breeding in zoos • Release in wild slowly • National Parks • Protect areas of land from deforestation • Gives species habitats that have been lost