Humans in the Biosphere Chapter 6 Humans in the Biosphere Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Chapter 6 Section 1 A Changing Landscape What types of human activities affect the biosphere? Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Objectives Describe human activities that can affect the biosphere. Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Human Activities Hunting and Gathering Agriculture Industry Urban Development Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Hunting and Gathering Subsistence Hunting Over Hunting Non demanding Use only what is needed Over Hunting Reduces populations Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Agriculture Farming Domestication of Animals Modern Technique Dependable food supply Domestication of Animals Overgrazing Soil erosion Water supply Modern Technique Irrigation Machinery Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Green Revolution Increase food supply to help feed poor Monoculture New strains of crops Larger yields Less nutrients Less water Monoculture Plant fields with one strain positive - greater yields negative - more susceptible to pests Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Industrial Growth and Urban Development Machines & Factories Large scale agriculture Better food supply More products – less effort Mobility Suburban sprawl Industrialization Higher energy requirements Higher waste production Air Damage Water Damage Soil Damage Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Chapter 6 Section 2 Renewable and Nonrenewable Resources How are environmental resources classified? What effects do human activities have on natural resources? Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Objectives Explain how environmental resources are classified. Describe how human activities affect land, air, and water resources. Identify the characteristics of sustainable use. Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Tragedy of the Commons Natural resources are available to everyone to use. No one is responsible to preserve resources Natural resources will eventually be destroyed. Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Types of Resources Renewable Nonrenewable Can regenerate, so it is replaceable Trees – lumber Water Soil Nonrenewable Cannot be regenerated by natural processes Fossil fuels – coal, natural gas, oil Mineral ores – iron, aluminum Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Sustainable Use Way to use natural resources with out depleting them. Human use with out harm Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Land Resources Soil is needed for crops Sustainable practices Soil erosion Caused by plowing Desertification Caused by farming, overgrazing, natural cycles Sustainable practices Contour plowing – across slopes Leave crop roots in soil Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Forest Resources Deforestation Old Growth Forests Sustainable Use Soil erosion Old Growth Forests Nonrenewable – never been cut Sustainable Use Forest Management Cut old trees Breed faster growing trees Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Ocean Resources Overfishing Sustainable Use Harvested faster than can grow Cod, halibut, salmon, herring, king crab Sustainable Use Close fisheries Not possible in international waters Aquaculture Can cause pollution Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Air Resources Emissions – industry, transportation Corrective Measures Smog – health issues Particulate matter – Acid rain – damage water resources Corrective Measures Auto emission control Smokestack scrubbers Clean Air Legislation Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Water Resources Water Pollution Sustainable Use Runoff – fertilizers, pesticides Sewage – microorganisms cause disease Sustainable Use Maintain natural wet lands Water conservation Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Chapter 6 Section 3 Biodiversity What is the value of biodiversity? What are the current threats to biodiversity? What is the goal of conservation biology? Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Objectives Define biodiversity and explain its value. Identify current threats to biodiversity. Describe the goal of conservation biology. Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Value of Biodiversity Provides food, industrial products, medicines – some yet to be found Biodiversity different species in biosphere Ecological Diversity different habitats, communities, and processes Genetic Diversity different genetic information within species Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Threats to Biodiversity Human activities Habitat reduction Farming Urban development Species Extinction Hunting – poaching – animal part trafficking Habitat destruction – fragmentation - Toxins in food web – biological magnification Introduction of foreign species Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Pollution DDT – insecticide Biological Magnification Raptor endangerment Weakened egg shells Biological Magnification Poison concentrated in food web Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Invasive Species Foreign species introduced by man Rapid reproduction No natural predators Loosestrife plants Zebra mussels Mediterranean fruit fly Kudzu vine Gypsy moth Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Conservation Management of natural resources Protect habitat Wildlife Preserves National Parks Protect wildlife Endangered Species Act Protect ecosystems Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Chapter 6 Section 4 Charting a Course for the Future What are two types of global change of concern to biologists? Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Objectives Describe two types of global change of concern to biologists Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Ozone Depletion Ozone Layer O3 gas Absorbs UV light Mutagen – changes DNA CFC’s catalyze O3 breakdown Aerosols Refrigerants AC, refrigerators, freezers Update Jan 10, 2004 Created by C. Ippolito Jan 2004

Global Warming Increase in the average temperature over past century +0.5°C in last 120 years Last 20 years rate increasing Greenhouse Effect CO2 in atmosphere Update Jan 10, 2004 Created by C. Ippolito Jan 2004