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PPD 132ESS 182 Sustainability 2 Spring 2010. Lecture 7: Natural Resources Professor Richard Matthew. Lecture on Natural Resources Q and A Group Projects. Overview. Lecture on Natural Resources. Lecture on Natural Resources.
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PPD 132ESS 182 Sustainability 2Spring 2010 Lecture 7: Natural Resources Professor Richard Matthew
Lecture on Natural Resources Q and A Group Projects Overview
Lecture on Natural Resources • http://www.ted.com/talks/lang/eng/yann_arthus_bertrand_captures_fragile_earth_in_wide_angle.html • http://www.ted.com/talks/lang/eng/steven_cowley_fusion_is_energy_s_future.html
Lecture on Natural Resources • Non-renewable resources: coal, oil, natural gas, metals, minerals • Concerns: • Climate change • Air pollution • Competition for strategic minerals • Environmental impacts of extractive industries • Discovery • Development • Construction • Operation • Wealth sharing • Decommissioning
Lecture on Natural Resources • http://www.youtube.com/watch?v=68bKMtncSuw&feature=related
Lecture on Natural Resources • Area of concern: the unsustainable use of renewable resources • What are renewable resources?
Lecture on Natural Resources • Energy: solar, wind, geothermal, hydro • Water • Genes, species and living systems are in a sense renewable: • Create • Convert • Construct • Reproduce
Lecture on Natural Resources • Oceans: • 70% of earth’s surface • 97% of the world’s water • Hold and distribute heat • Contain dissolved gases (e.g. CO2) thus regulating atmosphere • Aquatic life, starting with seaweed, algae and bacteria, culminating with seals, dolphins and whales • 250,000-10 million species
Lecture on Natural Resources • The food web of the OPEN OCEAN depends on plants (e.g. phytoplankton) in the sunlit EUPHOTIC ZONE which feed other species (e.g. zooplankton) initiating a complex food web • The BATHYAL ZONE contains shrimp, squid, octopi, etc • The ABYSSAL ZONE contains strange translucent species dependent on thermal energy
Lecture on Natural Resources • Disagreements over how much we can safely harvest from the open ocean • Major problem: Hardin’s Tragedy of the Commons • Humans cannot only kill off marine species, but destroy entire seas (e.g. Black Sea, Mediterranean Sea) through overfishing, oil spills, industrial discharges, runoff, nutrient pollution, wetlands destruction and the introduction of alien species
Lecture on Natural Resources • Chapter 17 of Agenda 21 recognizes the value of the “marine environment” and the need to treat it as a whole • Key document 1982 UN Convention on the Law of the Sea establishes territorial sea (12 miles), contiguous sea (24 miles), exclusive economic zone (200 miles) and high seas (beyond 200 miles), which gives the US control of 4 million square miles of ocean • Not ratified by US but largely respected • Still, ocean degradation a major source of concern and we are losing a renewable resource that is a major source of protein for humankind
Lecture on Natural Resources • The area between the high tide line and the continental shelf is known as the COASTAL ZONE • This includes the world’s most diverse ecosystems, coral reefs (which also sequester carbon) • What endangers them?
Lecture on Natural Resources • Along the shoreline are COASTAL WETLANDS, including mangrove swamps, salt marshes and mudflats, which are home to birds and reptiles as well as aquatic life forms • What endangers them?
Lecture on Natural Resources • Fresh water: • Constitutes 3% of the world’s water, and most of that is (currently) locked in polar ice • In a sense fresh water is renewed by the hydrological cycle through which ocean water evaporates and is carried onto land where it is deposited as snow and rain that feeds STREAMS, RIVERS, LAKES and INLAND WETLANDS • Each of these is an important habitat that plays a vital role in the world’s food webs, upon which we depend
Lecture on Natural Resources • Streams: fast flowing and meandering
Lecture on Natural Resources • Lakes: eutrophic (food rich) and oligotrophic (food poor) contain • Limnetic zone Littoral zone • Profundal zone • Benthic zone
Lecture on Natural Resources • Inland wetlands: sponge-like and highly productive, they provide numerous services including serving as a habitat
Lecture on Natural Resources • Key document: Chapter 18 of Agenda 21: • PROTECTION OF THE QUALITY AND SUPPLY OF FRESHWATER RESOURCES: APPLICATION OF INTEGRATED APPROACHES TO THE DEVELOPMENT, MANAGEMENT AND USE OF WATER RESOURCES • 18.1. Freshwater resources are an essential component of the Earth's hydrosphere and an indispensable part of all terrestrial ecosystems. The freshwater environment is characterized by the hydrological cycle, including floods and droughts, which in some regions have become more extreme and dramatic in their consequences. Global climate change and atmospheric pollution could also have an impact on freshwater resources and their availability and, through sea-level rise, threaten low-lying coastal areas and small island ecosystems. • Examples of unsustainable use?
Lecture on Natural Resources • Land systems are called BIOMES, and from these we obtain renewable resources we use for a variety of goods including food, construction, fuel, and medicine • Key determinants of a biome: latitude and elevation
Lecture on Natural Resources • Main biomes: • Tundra (low heat and light, slow growth, low productivity)
Lecture on Natural Resources • Boreal forest (cold, wet, 11% of land, coniferous, attractive for logging)
Lecture on Natural Resources • Temperate deciduous forest (Eastern NA, wet, layers of hardwood, shrub and moss, largely decimated to create farms)
Lecture on Natural Resources • Grassland (windy, not enough rain for forest, great for grazing)
Lecture on Natural Resources • Deserts (low precipitation, may be cold, temperate or hot, lots of wind, fragile ecosystems)
Lecture on Natural Resources • Tropical rainforest (15% of land, high diversity, often poor soil)
Lecture on Natural Resources • Tropical grassland (or savanna, 11% of land, long dry seasons alternate with very wet seasons)
Lecture on Natural Resources • Climate change and food production to 2050
Lecture on Natural Resources • http://www.youtube.com/watch?v=u0EEXWyhjM8
Lecture on Natural Resources • Unsustainable practices (over harvesting, polluting, logging, modifying) are placing these resources at grave risk around the world • Challenge: how can we reduce the demand for renewable resources?
Lecture on Natural Resources • What you can do:
Lecture on Natural Resources • Case study: Sustainable forestry • http://archives.cbc.ca/IDCC-1-75-679-3934/science_technology/clearcutting/ • http://archives.cbc.ca/IDCC-1-75-679-3939/science_technology/clearcutting/