2 A Changing Landscape Human activities Among human activities that affect the biosphere are hunting and gathering, agriculture, industry, and urban developmentHuman participate in food web and chemical cyclesHuman change the local and global environments
3 A Changing Landscape Hunting and gathering people who obtain food by collecting and hunting wild animals.Some scientist hypothesize that 12,000 years ago caused major extinction.Example – woolly mammoths, saber-tooth cats
4 A Changing LandscapeAgricultural Revolution – When hunters and gathers started collecting seeds to plant and domesticating animals.agriculture provides human society with fundamental needsdependable food supplylarge quantity of foodStorage for excess food
5 A Changing LandscapeMonoculture – large fields planted with one type of cropFertilizer – chemical or natural boost for plant growthPesticide – chemical or natural controls for pest or insectsGreen revolution – the use of genetic hybrids, monoculture and chemical fertilizers the increased world food supplyChallenges for the futureMore insectsMore pesticides – kill good insects, produce runoff, contaminate water supplyIrrigation
6 A Changing LandscapeIndustrial revolution – the shift from animal muscle to energy provided by water and fossil fuels which brought about sophisticated machines.Pros – mass production of materials, more advanced machines, more mobility, advance medicineCons – air pollution, soil pollution, water pollution, waste disposal.Pollution – An undesired change in air, water or soil that adversely affects the health, survival, or activities of humans
7 Renewable and Nonrenewable Resources Natural resources – any natural material used by humansRenewable resource – sources that can be replaced. Give some examples!Nonrenewable resourced – a resource that is consumed at a faster rate than replenished.
8 Renewable and Nonrenewable Resources Sustainable development – a way of using natural resources without depleting and providing for human needs without causing long term environmental harmHumans affect quality and supply of all resources
9 Renewable and Nonrenewable Resources Land resources – provide space for human communities and raw material humans needFood grow best in fertile soil made up of a mixture of sand, clay, rock particles and humusPlowing of soil remove roots that hold soil togetherSoil erosion – wearing away of soil by wind or waterDesertification – the process where over farming and dry conditions turn a once productive area into a desertWays to keep it from happeningLeave stems and roots from previous crop on farmlandSowing a fast growing cover - rye
10 Renewable and Nonrenewable Resources Forest resources – important resource for products they provide and the ecological functions they performWood is used for fuel and building materialForest canprovide nutrientsProvide habitatLimit soil erosionModerate climateProtect fresh water supplyDeforestation – loss of forestSpecies can be lostSevere erosionChange soil and microclimates
11 Renewable and Nonrenewable Resources Fishery ResourcesFishes and other animals that live in water are valuable source of foodOver fishing – harvesting fish faster than they can reproduceDeclining of fish is an example of the tragedy of commonsOver use of and areaFisheries help replenish this resourceSustainable Development – regulations that help the fish pollution to recover.Guidelines can specify how many fish and what size of fish can be caught in a given areaAquaculture – the raising of aquatic organisms for human consumptionHelps sustain populations
12 Renewable and Nonrenewable Resources Air Resources – resources the air provides organismsOxygen, carbon dioxide, nitrogenCondition of air affects peopleSmog – mixture of smoke and fog usually found in highly populated regionsPollutant – harmful material that can enter the biosphere through the land, air or waterAcid rain – rain with high acidity. Caused by burning of fossil fuels that release sulfuric and nitric acid into the air.
13 Renewable and Nonrenewable Resources Freshwater ResourcesWater is a renewable resource but freshwater is limitedMajor priority must be given to protect freshwater from pollution.Protecting wetlandsProtect forest \protect swampsPrevent soil pollution
14 BiodiversityBiodiversity – the sum total of the genetically based variety of all organisms in the biosphereEcosystem diversity – the variety of habitats, communities, and ecological processes in the living worldGenetic diversity – the total sum of all the genetic information carried by all the organisms on earthBiodiversity is one of the earth’s greatest resources.Species of many kinds have provided us with food, industrial products, and medicine.
15 Biodiversity Threats to biodiversity Hunting species to extinction Introducing toxinsIntroducing foreign species to new areasAltering habitatsExtinction – when a species disappears from all or part of it’s rangeEndangered species – species population size declines to almost extinctionHabitat fragmentation – splitting of ecosystems into piecesDevelopment of farms or communities