Unit 6 Biodiversity Environmental Science 1 Biodiversity Variety

Unit 6: Biodiversity Environmental Science 1

Biodiversity • Variety of living things, number of kinds 3 Components of BD: • 1. Ecological diversity – different habitats, niches, species interactions • 2. Species diversity – different kinds of organisms, relationships among species • 3. Genetic diversity – different genes & combinations of genes within populations 16 June 2010 Biodiversity. ppt 2

Benefits of Biodiversity • Ecosystem functions • Ecosystem services • Cleaning water, • Cleaning air, • Habitat & breeding areas for wildlife, … • Aesthetic and cultural benefits 16 June 2010 Biodiversity. ppt 3

Natural Resources • Vital economic natural resources – Renewable • • • Forests (plants, wildlife) Soils Fresh water (lakes, rivers) Wildlife and fisheries Rangeland – Nonrenewable • Minerals • Fossil Fuels 16 June 2010 Biodiversity. ppt 4

Natural Resources • Management of natural resources – Assure availability of resources for the future – Three “philosophies” • Maximum sustained yield • Ecosystem-based management • Adaptive management 16 June 2010 Biodiversity. ppt 5

Benefits of Biodiversity • New food sources – Grains, fruits, vegetables, meat, fish 16 June 2010 Biodiversity. ppt 6

Benefits of Biodiversity • Medicines • Plants • Jellyfish & sea anemones • Nudibranchs • Marine slugs 16 June 2010 Biodiversity. ppt 7

Biodiversity • How much biodiversity ü 1. 7— 2. 0 million species ü Estimates to 100 million 16 June 2010 Biodiversity. ppt 8

Biodiversity • Where is the biodiversity – Everywhere • Every continent and habitat has unique life forms – Concentrated in the tropics • Panama: > 500 species of breeding birds • Arctic: 50 -100 species – Dense concentrations 16 June 2010 Biodiversity. ppt 9

Threats to Biodiversity • Extinction and population reductions – Hunting and overharvesting • • Tiger Dodo Whales Sharks – Habitat loss 16 June 2010 Biodiversity. ppt 10

Threats to Biodiversity • Extinction and population reductions – Pollution – Climate change – Invasive species 16 June 2010 Biodiversity. ppt 11

Protecting Biodiversity • How can we protect biodiversity – Stop overharvesting • Sustainable yield • Hunting & fishing laws (every state ? ) – in developing nations ? – Protect habitat • Refuges, parks, preserves – Endangered Species Act 16 June 2010 Biodiversity. ppt 12

Protecting Biodiversity • Refuges, parks, preserves – How big should refuges be? – Where should they be? – Mc. Arthur & Wilson “Theory of Island Biogeography” • colonization rate • extinction rate (local) • predicts number of species 16 June 2010 Biodiversity. ppt 13

Protecting Biodiversity • Island Biogeography – Island size predicts number of species 16 June 2010 Biodiversity. ppt 14

Protecting Biodiversity • Island Biogeography – Everyplace is an island – Habitat fragmentation • Smaller fragments hold fewer species 16 June 2010 Biodiversity. ppt 15

Protecting Biodiversity • Endangered Species Act (1973) – Goal to “recover” species so they no longer need protection under ESA – Implements U. S. participation in CITES • “Convention on International Trade in Endangered Species” • Prohibits trade in listed species – whole organisms – parts: skins, bones, teeth, flowers, leaves, etc. • Other laws: – – Marine Mammal Protection Act Migratory Bird Treaty Act Anadromous Fish Conservation Act etc. 16 June 2010 Biodiversity. ppt 16

Protecting Biodiversity • Endangered Species Act (1973) – Listing of “endangered” and “threatened” species – Restricts development of habitats – Captive breeding programs • Release of captive bred stocks to enhance or recover wild populations. 16 June 2010 • http: //www. fws. gov/ endangered/ Biodiversity. ppt 17

Protecting Biodiversity • Biodiversity “hotspots” – Protection of habitat 16 June 2010 Biodiversity. ppt 18