importance of biodiversity & human impact Flashcards
what are some changes in physical damage?
discarding waste
what are some changes in water turbidity?
-increased by ploughing, mining, dredging
- blocks gills
- reduces light
what are some changes in pH?
-acids: mine drainage, burning fossil fuels, smelting
-proteins (enzymes) can denature
-calcium based exoskeletons can dissolve
what are some changes in dissolved oxygen?
-hot discharges
-sewage
what are some changes in temperature?
-growth and survival of species
-distribution of species could change
-could increase growth rates or decomposition
what are some negatives of draining?
-wet or dry soil with deep cracks & rain falls within few days of agrochemical application
-field drains can provide rapid route for water enriched with ammonium, phosphorus, pesticides
-drains most effective at providing conduct for agricultural pollutants when newly installed or in fields with deep cracking clays
what are some positives of drainage?
-maintain good field drainage & good soil structure reduces water logging
-reduces likelihood of causing soil compaction through untimely field operations
-decreases surface runoff, soil erosion & loss of sediment + associated pollutants
how much argicultural land in england and wales has been drained with piped systems?
6.4 million hectares
what is the thermohaline circulation?
deep ocean currents that circulate warm and cold water around the globe
what is changing the thermohaline circulation?
melting ice caps
what is the equation for bicarbonate?
h2co3 -> h+ + hco3
what is the equation for carbonic acid?
co2 + h2o -> h2co3
how much estimated carbon dioxide dissolves in oceans?
20-30%
what is the biggest indirect threat affecting biosphere?
global warming
why is the population expanding?
more demand for food, water, land, jobs, energy. resources all greatly impact biosphere, reducing biodiversity
what is habitat provision in ecosystem services?
one species may provide habitats for others
what is seed dispersal in eco services?
- by animals rather than wind
- larger (more nutrients)
- dropped
- passed through gut
what is pollination in ecosystem services?
- by insects and animals
- many species have evolved to attract specific pollinators
what is food in ecosystem services?
all heterotrophs rely on other organisms for energy and nutrients
what is interspace relationships in ecosystem services?
no species can live in ecological isolation (on their own)
what is soil maintenance in ecosystem services?
- decomposition by invertebrates, fungi, and bacteria
- recycle nutrients
what are biogeochemical cycles in ecosystem services?
- carbon nitrogen, phosphorus cycles
- mostly through bacteria and fungi
- without these cycles, waste products would build up,important nutrients would be depleted
what is the hydrological cycle in ecosystem services?
- transpiration causes water vapour
- vapour forms clouds
- controls surface temps
- increases rain
what is atmospheric composition in ecosystem services?
-abiotic and biotic processes cancel each other out
-reach a dynamic equilibrium
what are centres of diversity?
- nikolai vavilov realised some areas have important cwr species
- called centres of diversity, centres of origin, or vavilov centres
- these areas are under threat of environmental degredation
what are some examples of improved taste or appearance?
- sweeter pineapples with yellower flesh been selectively bred since 1990s
- selective breeding for characteristics may result in loss of desirable characteristics
what are some examples of high yield?
oil palm yields have been increased by 25% by cross breeding with wild varieties found in central africa
what are some examples of resistance to drought?
varieties of cacao, that are more drought tolerant have been developed by cross breeding with wild plants from amazon rainforest
what are some examples of salt tolerance?
- introduction of salt tolerant characteristics from wild varieties of rice led to breeding commercially cultivated varieties that can be grown in saline soil
- sea kale is salt tolerant and has been studied for use in breeding programmes with related crop species
what are some examples of disease resistance?
- sugar can has been protected from sugar cane mosaic virus by cross breeding with wild sugar cane varieties from indonesia
- single wild species of tomato provided the genetic characteristics for resistance to 9 diseases of commercially grown tomato varieties
what are crop breeding programmes? part 1
- domesticated crops lack genetic diversity as theyve been produced from limited number of original plants
- search for new characteristics that can be bred into commerical crops focuses on wild plants of same species (cwr)
what are crop breeding programmes? part 2
- many cwr species are naturally fond in areas where environmental degredation threatens survival
- varieties grown in subsistence farming areas, likely to have desirable characteristics
why may herbivores be introduced to control pests?
to control weeds, especially if weed species is non-indigenous and not eaten by indigenous herbivores
1. prickly pear cactus became a weed after introduction to australia. cactoblastis moth introduced to control it
how can populations of natural predators be increased?
predators like ladybirds and ground beetles can be increased by providing suitable habitats like hedgerows or beetle banks
what are used in the study of disease and vaccine production?
armadillos
what has provided a better understanding of things such as heart disease, strokes, cancer?
human nerve cells are small and difficult to study, squid nerve cells are larger and therefore easier to study
what has been developed to make ultrasound scanner 3d images?
studying dolphins and bats that use high frequency sound to echo-locate their food has enabled the development of new ultrasound scanners that give better 3d images for medical diagnosis
what is being developed to prevent the rejection of human organs?
marine sponges produce proteins that prevent the rejection of grafts from other individuals, these proteins are being developed
what is being studied to help improve the treatment of burn victims?
hippopotamus’ skin secretes hipposuduric acid, which is a natural sunscreen and antimicrobial agent
what has helped in the developmental problems in unborn babies?
studying a developing kangaroo or wallaby in its mothers pouch is easier than studying a human baby of the same age in its mothers womb
what was the mexican yam used for?
from central american rainforests, it was the source of diosgenin thats used to make steroid medicine such as contraceptive pill
where is taxol extracted from?
the yew tree and used to treat a range of cancers
where was aspirin extracted from?
the bark of willow tress, it is now manufactured synthetically
what was used for malaria protection?
cinchona tree- quinine
what are poppies cultivated for?
to produce painkillers, morphine and codeine
what features have been copied from living organisms in materials?
silk produced by spiders is being copied to produce better car airbags and body armour
what features of living organisms have been copied in adhesion?
- toes of gecko lizards have pads that provide strong adhesion, attempts are being made to copy this adhesion without glue
- seeds of some plants have burrs with hooks which stick to passing animals and aids seed dispersal, this was copied in development of velcro
what features of living organisms have been copied in architecture?
- bird wing bones are hollow and have struts to stop them from bending or breaking, this has been copied in designs of bridges and roofs
- termite mounds create a convection current, this has been copied in shopping complexes and office buildings, creating ventilation without air conditioning
what features of living organisms have been copied in vehicle design?
- splayed wingtip feathers of birds reduce wind turbulence, copying this structure improved aircraft wing designs to increase fuel efficiency
- shark skin has scales that reduce friction while swimming, ridges created by the scales have been copied for aircraft and ship surface coatings reducing fuel consumption
what is biomimetics?
knowledge and decisions over habitat conservation to protect those species that havent yet been investigated
what are some keystone species?
- wolves-regulate prey populations
- beavers-ability to shape freshwater habitats
- grizzly bears-disperse seeds, fertilise forests
- elephants-tusks dig up dry riverbeds creating watering holes
5.sharks- top of food chain, regulate prey populations
what is a key stone species?
some species can be removed without apparent effect, some may have enormous effects on remaining species
which species are at risk?
-species at top of food chain
-endemic local species
-species with small populations
-migratory species
-species with complex life cycles
-specialist species
what is the reason for mass extinction?
massive climate or environmental shift
what are some reasons for extinction?
-disease
-poachers
-food loss
-habitat loss
-competition
-new life
-pollution
how many species have been named?
close to 10 million, 1.4 million named
- 250,000 plants, 750,000 insects
how can biodiversity be measured?
1.genetic- variation between individuals in a population
2.species-number of species in given area
3.ecosystems-plants/ animals/ geology/ soil/ climate
what are some resources?
1.fibres-silk,cotton
2.wood-fuel,building,paper,furniture
3.oil-rapeseed,sunflower,peanut
4.fuel-fossil fuels (coal,oil,gas)
5.food-plants,animals,micro-organisms
