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Name_________________________ What CAREER are you interested in pursuing?____________________________ What math class are you in now (or last semester)?_________________________ Grade in it______________ Recommended science for next year:___________________________________________________________________ G3: Impacts of Humans on Ecosystems (6 hours) G.3.1 Calculate the Simpson diversity index for two local communities. • D = diversity index • N = total number of organisms of all species found • n = number of individuals of a particular species • D = [N(N-1)] / [sum of n (n-1)] • Have to record total # of individuals & # of each species • Example… Sample two dune communities: Plant species n n(n-1) 3(2)=6 Plant species n n(n-1) Oak tree 3 Marram grass 50 50(49)=2450 Hickory tree 1 Milkweed 10 Maple tree 1 Poison ivy 10 Beech tree 1 Sand cress 4 Fern 5 Rose 1 Moss 3 Sand cherry 3 Columbine 3 Totals N=78 2648 Trillium 3 Virginia creeper 4 Solomon seal 3 Totals N=27 62 G.3.2 Analyse the biodiversity of the two local communities using the Simpson index. Calculate D!! • Foredune D = 78(77)/2648 = 2.27 • Mature dune D = 27(26)/62 = 11.3 More diverse, although total plant #s is less!!! Higher # of diff. species Sample it periodically...health of ecosystem! G.3.3 Discuss reasons for the conservation of biodiversity using rainforests as an example. Reasons should include ethical, ecological, economic aesthetic arguments. • Aim 8: There are environmental issues affecting the whole planet and also ethical issues involved in conservation that could be raised here. • PLANET EARTH VIDEO...IMAGINE YOURSELF THERE... • Rain forest example... Reasons to Conserve the Rain Forest • Economic – Most nutrients in plants, not in soil – Logging nutrient-poor soil – Sources of medicines, chemicals...could go extinct – Ecotourism • Ecological – Keystone species may be lost – All species of ecosystem interdependent – Invasives – if low diversity, less likely to sustain pressures – Plants are CO2 sink, remove it from atmosphere...global warming. – Soil erosion, flooding • Ethical – Local human populations! – Help them make a living from it while preserving it – Ethical responsibility to conserve it for future generations, reduce human impact, increase education/awareness • Aesthetic – Ecotourism, boosts human well-being – Inspiration for artists, writers, photographers, ... G.3.4 List three examples of the introduction of alien species that have had significant impacts on ecosystems. • accidental release of invasive species – Zebra mussels, 1980s, maybe from ballast water to US/Lakes – Clog pipes (factories, etc) – High repro. Rate, so overgrow quickly – Is filtering water of Lake Michigan very well….good or bad??!?!?! More light, more growth of plants, may be better habitat for fish…or not. – $500 billion in next 10 years! • deliberate release of invasive species – Kudzu, from Japan to US 1876 (ornamental plant); 1930s promoted for soil conservation by govt – 1953-Dept Ag: It’s a pest weed! – Common in SE, grows quick, horiz. And vert.; US loses $500 million annually b/c of it G.3.4 List three examples of the introduction of alien species that have had significant impacts on ecosystems. • biological control – Prickly pear cactus, Australia, 1800s introduced on purpose – 1900s spreading too quickly – Research…how to control it biologically? – MOTH feeds on it…introduce moth to Aust. – Currently in balance • xref- precautionary principle-5.2.4 G.3.5 Discuss the impacts of alien species on ecosystems. Named examples of each: • Inter-specific competition – Red squirrel (UK): grey squirrel (US) introduced to UK 1800s, outcompeting, pushing out of habitat. Now, RED only occurs where grey not inhabiting. No documented damage...yet. • Predation – St. Lawrence Seaway allowed ocean fish to travel to fresh water – Sea lampreys invaded area, preyed on lake trout, pop declined; lamprey then preyed on whitefish...their pop declined – Introduced salmon to replace whitefish and trout in L.Michigan – Sought-after gamefish (tourist $$$), eats small ocean-fish invasives G.3.5 Discuss the impacts of alien species on ecosystems. Named examples of each: • Species extinction – Lake Victoria-80% cichlids – 1950s-overfishing – Introduced Nile Perch to increase pops – 1970...cichlids only 1%! (200 of the 400 cichlid species now extinct b/c competition) – “benefit” for fishermen; “bad” for diversity G.3.6 Outline one example of biological control of invasive species. • Aim 8: Invasive alien species are such a widespread problem that it will almost certainly be possible to find a good local example. Such species are a real threat to the biodiversity of the planet, with many species facing extinction as a result. The uniqueness and cultural diversity of human populations are also being affected. • Biological control of pest species – Natural predator to control unwanted/invasives – Always a risk!! – Purple loosestrife: threat to native wetland plants; beetles used to control b/c larvae feed on plant – Red fire ants: introduced from SAmer., outcompete native ants (and OUCH!!!); phorid fly injects eggs into ant...larvae eat way to head and decapitate it!!! Current research...Gainesville, FL. G.3.7 Define biomagnification. • process in which chemical substances become more concentrated at each trophic level G.3.8 Explain the cause and consequences of biomagnification, using a named example. • Fat soluble chemicals work up the food chain! – Xref- food chains - 5.1.4 • organophosphorus pesticides: DDT – Mosquito control (didn’t know it persists decades) – Into water, plankton, fishes, … – Birds accumulate the highest levels – Egg shells weak/less Ca; offspring mortality • mercury in fish – Air pollution (factories, etc.) Hmmmm... • Developed countries pressure undeveloped countries to ban use of DDT • Mosquitoes are vector for malaria • Not using DDT has caused increase in malaria incidence • Do YOU think DDT should be allowed here or not? G.3.9 Outline the effects of ultraviolet (UV) radiation on living tissues and biological productivity. • Non-lethal skin cancer (basal, squamous cell carcinomas—decrease of 1% ozone increase cancers 2%! • Lethal skin cancer (malignant melanoma; 15-20% cases are lethal… early detection key!) • Mutation of DNA – Xref- DNA structure- 3.3.4/7.1 • Sunburn (enlarged blood vessels…some epidermal cells die, peel off) ewww! • Cataracts (clouding of lens, vision loss) SUNGLASSES!!! • Biological productivity reduced b/c plant loss (less photosynthesis, mutate plant DNA, phytoplankton & aquatic food chains! YIKES! G.3.10 Outline the effect of chlorofluorocarbons (CFCs) on the ozone layer. • Ozone protects from UV • Forms in stratosphere when O2 breaks apart and combines with another O – constantly being formed, broken down, and reformed • 1985: CFCs are thinning it (~20km thick) – Int’l: Montreal Agreement to phase out use – Fridge coolants – Aerosol propellants – Foam packing manufacture • CFCs break down, release Cl– O3 + Cl- ClO + O2 – ClO + O Cl- + O2 – Free Cl- breaks down another O3...1 CFC molecule can move to stratosphere in 15 yrs, remains there destroying ozone for a century! G.3.11 State that ozone in the stratosphere absorbs UV radiation. • There is a limit to UV absorption in the stratosphere. • There is no need to mention UV-A, UV-B and UVC. Group IV Project: Wed. April 6th • 2nd graders • Small groups, small lessons/demos/activities • They learn about: all the animal groups—insects, birds, plants (1st grade) – Life cycle stuff – Predators and prey • WHAT DO YOU WANT TO DO?!?! – Game/activity/skit/demo – YOU are INDIVIDUALLY GRADED…everyone must be ACTIVELY involved in all steps…