(4) sustaining ecosystems

• ecosystem = the system of interactions between living organisms and their environment - is made up of biotic and abiotic elements
• interdependence: soils to people = nutrients = helps crops grow
• interdependence: plants to people = food to eat, medicinal plants for medicine, supplies like wood for shelter, boats, fires etc
• interdependence: animals to soils = decomposition of dead animals make nutrients for rich soils = more fertile
• interdependence: plants to animals = food source and habitats - animals to plants = seed dispersal
• interdependence: animals to people = food as are hunted, fur to keep warm
• interdependence: plants to soils = roots help stabilise soils, decomposition of leaves gives soils nutrients
• water cycle = convectional rainfall, evapotranspiration of of plants - recycled precipitation
• deforestation effects water cycle - less trees = less evapotranspiration = less moisture in atmosphere = less rainfall
• convectional rainfall = water evaporates to clouds, rains and recycles into clouds to rain the next day
• soils - called latosols, thin humus layer but thick leaf litter, red in colour = lots of iron - acidic pH, shallow soils = fast transfer of nutrients - lack minerals, chemical weathering - weak soils, deforestation - less nutrients as less leaves = less fertile, not very fertile as there is few nutrients, minerals leeched from soils by rainfall, rapid nutrient cycling
• flora adaptation - buttress roots: supports tallest trees - climbs sides and are 3 meters above ground
• flora adaptation - trees: thin trunks = compete for sunlight and space so grow up not our, dark green leaves = chlorophyll is dark from much photosynthesis, drip tips = shed excess water = lighter
• fauna adaptation - toucans: bright coloured beak = attract a mate, sharp beak = break nuts and berries to eat
• fauna adaptation - sloths: long arms = climb trees and help swim in floods, sharp claws = help grip to trees when sitting and climbing (stability)
• fauna adaptation - jaguars: strong jaws = pierce preys skull, good swimmers = help to catch prey
• nutrient cycle - biomass = biggest circle, leaf litter = middle circle, soil = smallest circle
• nutrient cycle - biomass has quick uptake of nutrients from soil to grow, leaf litter decomposes quick to make nutrients and replenish soils, biomass characteristics change = roots close to surface for quick uptake of nutrients
• distribution of tropical rainforest = near equator - 23.5 degrees N+S
• distribution of hot desert = 15-35 degrees N+S of equator
• distribution of polar reigions = 60 degrees N+S, near poles
• distribution of tropical savana = 5 - 30 degrees N+S of equator
• distribution of temperate grasslands = 40-60 degrees N+S of equator
• distribution of coral reefs = 30 degrees N+S of equator, few miles of coasts
• distribution of temperate forest = 40-60 degrees N+S of equator
• human activity in rainforest: road construction = provides access, removes trees for space and damages remaining trees, removes habitats
• human activity in rainforest: deforestation = less trees = less transpiration = less moisture in atmosphere
• human activity in rainforest: palm oil = slash and burn used to give soil many nutrients - cant be reused, profit majorly from production
• human activity in rainforest: logging = uses timber to produce paper, decreases habitats = less biomass = affects nutrient cycle
• human activity in rainforest: cattle ranching = cutting down trees for farming, ruins soils (no nutrients) = cant replant trees
• human activity in rainforest: mineral extraction = affects water cycle - absorbs water = no transpiration, uses minerals to make products = more profit to develop
• human activity in rainforest: hydroelectric power = need space = cut down trees and make people move - expensive, provides sustainable power - supports economic growth