Unit 2 Review

Topics Ecosystems- energy, food chains, webs Biomes (general, not specific) Nutrient cycles Succession and Eutrophication Biodiversity –Importance of –Threats to –How to protect

Ecosystems Producers, consumers Who eats what? Herbivores, Omnivores and Carnivores Trophic levels and energy- more energy at the bottom (plants) than top (predators) Role of decomposers Be able to read a food web/chain and identify trophic levels

Biomes Difference between weather and climate Climate, altitude, latitude determine flora Plant life determines animal life Know the biome YOU live in

Nutrient Cycles Carbon, Nitrogen, Phosphorus- never run out, just continually cycle through earth systems C-cycle: –Photosynthesis/Respiration: trades carbon between life and atmosphere –CO2 can be dissolved in surface waters and used by marine life –C can be stored in sediments to become future limestone or fossil fuels –Humans burning fossil fuels release more CO2 into atmosphere

Nutrient Cycles N-cycle –We cannot use atmospheric Nitrogen (N 2 with a triple bond) –Nitrogen fixation converts N 2  nitrates, ammonia which plants can use –N fixing bacteria do this in soils and roots of legumes –Denitrification: bacteria convert usable nitrogen back to N 3 –Humans: fix nitrogen to make fertilizers

Nutrient Cycles P-cycle –Phosphates found in rocks –Weather and water dissolve phosphates in water for plants to uptake –Humans get P from plants and animals –Humans mine phosphates and use them as fertilizers

Eutrophication Succession happening too quickly in an aquatic ecosystem Excessive N and P enter ecosystem, algae blooms Decomposers eating dead algae use up all available oxygen Lake/pond slowly suffocates life inside Human influence: fertilizer runoff, animal waste, detergents

Succession The evolution of an ecosystem Primary- no soil there before (bare rock) Secondary- soil present, ecosystem disturbed Pioneer species- first to colonize area Climax community- end result, mature ecosystem Takes a long time years

Biodiversity- Importance Agriculture- need different crops in case one fails Medical- untapped medicines in organisms yet to be researched/discovered Ethical- all organisms deserve right to life Aesthetic- variety is pleasing, beautiful, ecotourism Ecosystem stability- remove one species, the whole system could collapse; everything’s important

Biodiversity- Threats Mass extinctions have happened naturally but humans are creating their own by –Habitat destruction and fragmentation –Introducing invasive species –Pollution –Over-hunting/harvesting –poaching

Biodiversity- Protection Saving a species: captive breeding, preserving genetic specimens, zoos Ecosystem approach –Setting aside wilderness areas, nature preserves, national parks –Federal Laws: Wilderness Act, ESA –International treaties: CITES to help poaching and animal trade Why don’t people care? –not a priority, unaware

Species? Endemic- native; only found there Keystone- crucial to function of ecosystem Pioneer- colonizes landscape first Invasive- non-native, destructive Threatened- about to be endangered Endangered- about to be extinct

Don’t forget... Biodiversity Hotspot Socratic/Articles Case Study Parking Lot lab Biome project HW packet

Trash Ball Review Game 2 teams Everyone has number on each team: 1A, 1B, 2A, 2B Each person is asked a question individually If correct, +1 point AND they can shoot trash ball into basket for extra points –Across room +3 –6 feet away +1