EQ2-functioning ecosystems Flashcards
wetlands
-areas of land that are either permanently or seasonally covered w water, supporting species that r adapted to live there
-act as a temporary water stores within the hc, help mitigate from river floods due to sudden storm discharge
-act as giant water filters by trapping + recycling nutrients + pollutants
-very high biological productivity+ support diverse food web
value of wetlands
-support life: stores + flows of carbon, nutrient recycling
-porvision of resources: fuelwood, fisheries, mammals + bird for tourism
-regulation conditions: regular supply of groundwater+ base flow of river, water purification, reduced flood risk
-cultural value: aesthetic value, recreational use, cultural heritage
Meteorological droughts impact on wetlands
-reduce interception due to less percipiation
-causes vegetation to wilt + die
-impacts soil nutrients levels+ rest of complex food web
desertification
wetland in pantanal
-lies in the upper paraguay river basin
-vital river floodplain-surronded by areas w seasonal rainfall so aquatic + bird life depends on the permament wetland for survival
-nov-april: change from terrestrial to aquatic habitats
-flooding covers 80% of it but even in dry years the river=permament
-wetlands near river retain up to 60% of floodwater throughout year
-surronded by forest that changes to savannah grassland
impacts of drought on pantanal
-it increased tree morality, which reduced habitats for wild animals
-wildfires became major threat caused by cattle ranchers deliberately setting old grass on fire during dry season to clear veg left ungrazed by their cattle
-those fires spread during the drought n went out of control
wetland in uk
-as supply of water is reduced areas of open water shrink/dry resulting in progressive loss of habitat
-soil moisture drys lead to soil erosion + reduced ability to store water in times of flood
-organic soils may oxidise- release C
-concentrations of dissolved nutrients may increase
rainforest ecosystems: the amazon
-amazon=earth lungs
-400 billion trees transport humidty inland from atlantic ocean
-20 billion tonnes of water vapour taken from forest and dujmped on s brazil as rain
-river carries 17 million tonnes back to atlantic each day via ‘sky river’
imapcts of drought on amazon
-young trees die so reduces canopy cover
-so reduces humidity + water vapour + thus rain
-tropical sunlight + dying veg = surface tree litter create tinderbox = fire
-wind + lightning storms make small fires into wild fires
