Human Impact Unit Chapter 6 Ms. Pelullo 2012 Viewed from space, the lights of human settlement are obvious. The brightest areas are the most developed but not necessarily the most populated. Development is one way in which humans, who today number over 6.5 billion, have affected the biosphere

6.1 – A Changing Landscape Agriculture Development Industrial Growth Monoculture: practice of planting a single productive crop, year after year Most important! Dependable food supply Development Growth of cities and suburbs is tied to the high standard of living. PRODUCE A LOT OF WASTE!!! Industrial Growth Requires a lot of energy to produce and power Burn Fossil Fuels (coal, oil, natural gas) Waste discarded into air/water/soil

Nonrenewable Resources Sustainable Development Sustainable development provides for human needs while preserving the ecosystems that produce natural resources. Renewable Resources Nonrenewable Resources Can be produced or replaced by a healthy ecosystem Examples: Wind Pine Tree Freshwater Marsh Grass Clean Air Natural processes cannot replenish them within a reasonable amount of time Examples: Fossil Fuels Coal Oil Natural Gas Minerals

6.2 Using Resources Wisely Soil Resources Healthy soil supports both agriculture and forestry Topsoil The mineral-and nutrient-rich portion of soil Can be renewable if it is managed properly Soil Erosion (Negative Effects on Soil Quality) Desertification: in the parts of the world with dry climates, a combo of farming, overgrazing, seasonal drought, and climate change can turn farmland into desert. Deforestation: a loss of forests

Freshwater Resources Water Pollution Pollutant: harmful material that can enter a biosphere. Can enter water supplies from: Single source – factory/oil spill  AKA  Point Source Smaller sources – grease/oil washed off from streets  AKA  Nonpoint Sources Biological Magnification: occurs if a pollutant (DDT) is picked up by an organism and is not broken down/eliminated from its body. Instead it collects body tissues

DDT (Biological Magnification)

Atmospheric Resources Air Pollution Smog: a gray-brown haze formed by chemical reactions among pollutants released into the air by industrial processes and automobile exhaust Acid Rain: rain containing nitrogen and sulfur compounds that have been released from factories burning fossil fuels Greenhouse Gases: burning fossil fuels & forests releases a stored carbon into the atmosphere as CO2 . (ex: methane) Particulates: microscopic particles of ash/dust released by certain industrial processes and certain kinds of diesel engines. Can cause serious health issues.

Ever been to Los Angeles, California??? Wake up to SMOG every day!!!  Particulates Greenhouse Gases

6.3 – Biodiversity The 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 in the biosphere Species Diversity: the number of different species in the biosphere in a particular area Genetic Diversity: the sum total of all the different forms of genetic information carried by a particular species.

Threats to Biodiversity  we are to blame!  Altered Habitats Elimination for agriculture/urban development Habitat Fragmentation: development which splits ecosystems into pieces. Hunting/Demand for Wildlife Products Pushing species to extinction CITES – the Convention on International Trade in Endangered Species  ban international trade

Threats to Biodiversity  we are to blame!  Introduced Species Organisms that are introduced to new habitats can become invasive & threaten biodiversity. Pollution DDT Acid Rain (stress on land/water organisms) Increased CO2 in the atmosphere is dissolving in Oceans, making them more acidic Climate Change Organisms are adapted to their environment – specific tolerance ranges to temperature… If conditions change, then the organism must relocate or face extinction

Conserving Biodiversity To conserve biodiversity, we must: Protect Individual Species Various associates designed to help oversee the survival of species Preserve Habitats and Ecosystems Governments and Conservation Groups have set aside land as parks & reserves. Marine Sanctuaries National Parks, Forests, and other protected areas Consider Local Interests Individuals change habitat/way of living Offer of rewards or incentives Tax Credits (for solar panels/hybrid cars)

6.4 – Meeting Ecological Challenges Ecological Footprint Describes the total area of functioning land and water ecosystems needed both to provide the resources an individual/population uses and to absorb & make harmless the wastes that individual/population generates

Human Population Growth http://www.census.gov/main/www/popclock.html LET’S CHECK IT OUT!