decomposition Flashcards
when plants/ animals die
organisms decayed by microorganisms in aerobic conditions of the soil
- broken down into smaller pieces until all carbon is released as carbon dioxide during microbial respiration
if decayed in anaerobic conditions, organisms slowly converted into fossil fuels
- FF burned by humans to release CO2 in combustion
recycling nutrients
important to provide nutrients that living organisms use to grow and reproduce
decomposition def
process by which dead organic matter is broken down into simpler organic or inorganic substances
decomp. importance
essential for recycling of nutrients throughout an ecosystem
what cause decomposition
detritus feeders (detrivores) - small animals like worms and woodlice
decomposers- microorganisms like bacteria and fungi
factors affecting rate of decomposition
oxygen availibility ( more O2 , more aerobic respiration, more energy, faster rate of growth and decomposition)
temperature ( more energy, faster RoR, more decomp.)
- if temp is too high, enzymes denature so rate decreases
water content- decomposers need water to survive ( if soil is waterlogged, O2 conc decreases, rate of decomposition decreases)
compost
mixture of dead organic material , used to fertilise and improve soil
prepared by leaving dead plant waste in aerobic, warm, moist conditions
biogas generators
breakdown organic material in anaerobic respiration (anaerobic decay)
produces mixture of gases called biogas (methane mainly)
combustion of methane produces lots of energy
less oxygen in generator, more methane produced
once biogas is removed, left over mixture contains lots of useful minerals and is used like fertiliser