Ecology Energy flowSuccession Human activities Combustion Overuse of chemicals - resistance development Lack of sustainability Agriculture Deforestation

Definitions A. population1. small localities in a habitat B. community2. the particular area occupied by a population C. habitat3. physical and chemical soil properties D. biotic4. the place of each species in the environment E. abiotic5. group of single species in an area F. edaphic6. the non-living environment G. climatic7. use of simple inorganic molecules to make organic energy compounds H. microhabitat8. the different populations that live in a habitat I. niche9. consumption of complex organic compounds J. autotrophic10. all the interacting organisms within a habitat K. heterotrophic11. variation of factors such as light, temp, moisture, salinity

Definitions A. population1. small localities in a habitat B. community2. the particular area occupied by a population C. habitat3. physical and chemical soil properties D. biotic4. the place of each species in the environment E. abiotic5. group of single species in an area F. edaphic6. the non-living environment G. climatic7. use of simple inorganic molecules to make organic energy compounds H. microhabitat8. the different populations that live in a habitat I. niche9. consumption of complex organic compounds J. autotrophic10. all the interacting organisms within a habitat K. heterotrophic11. variation of factors such as light, temp, moisture, salinity A- 5 B - 8 C - 2 D -10 E - 6 F - 3 G - 11H - 1 I - 4 J - 7 K -9

Energy flow Primary Producer/ plant/autotrophs Primary consumer/ herbivores/hetrotrophs Secondary consumer /primary carnivore Tertiary consumer/ top carnivore Usually no more than 5 links in a food chain. Why? detritivores, and decomposers/ saprobionts(extracellular digestion) Energy loss from sun to plants:- Reflection, evaporation, wavelength not absorbed, doesn’t hit leaf/chloroplasts Energy loss from plant to herbivore: - Indigestible material e.g. cellulose, respiration (heat), death and decomposition, not all plant eaten e.g. root Energy loss from herbivore to carnivore: -respiration (heat), death and decomposition, not all animal eaten e.g. skeleton, hair SUN 2-10% 0-2% 1-10% Pyramids – number – no account of size biomass – no account of season energy – kj/m 2 /year (not just standing crop)

Ecology calculations gross ecological efficiency - the rate at which energy passes into an animal at each trophic level e.g kj into primary and 1500kj into secondary consumer 1500 X 100 = 10% photosynthetic efficiency- the ability of a plant to trap light energy = quantity of energy incorporated into product quantity of energy falling onto the plant gross primary productivity - the rate at which products e.g. glucose is made by photosynthesis net primary productivity- the food available to be transferred after the plant has used some for respiration NPP + respiration = GPP secondary productivity - the rate at which consumers accumulate energy in cells /tissues

Succession Human influences Primary (e.g. bare rock) and secondary (e.g. post fire or after tree felling)

Human activities Deforestation Lack of sustainability Biodiversity endangered species (loss of habitat, hunting, over-fishing, introduced species, pollution, drainage of wetlands) extinction conservation (e.g. action taken to preserve fish stocks, managed forests) ecotourism Reasons :- timber, fuel, farming, building, paper Consequences : - climate change, loss of habitat, soil erosion, flooding

Combustion Overuse of chemicals - resistance development Selection pressure Heterozygous advantage Warfarin anticoagulant RR resistant to warfarin, high vit K needed rr killed by warfarin Rr resistant to Warfarin + low vit K needed Also sickle cell Antibiotic resistance overuse of antibiotics in agriculture and medicine random mutations conjugation between bacteria MRSA Carbon cycle carbon dioxide greenhouse gas/ effect global warming ice caps/ droughts/ desertification/ increased crop yields/ pests Kyoto agreement 1997 carbon footprint

Agriculture Artificial selection (inbreeding v outbreeding) homozygosity v hybrid vigour breeding programmes Removal of hedgerows Fertilisers - eutrophication, nitrogen cycle Pesticides (herbicides, insecticides)- bioaccumulation Monocultures Managed forestry - coppicing, selective cutting, long rotation time Drainage ditches; loss of bog land Growth of biofuels