Soil biology Flashcards
what is detritus?
organic matter made up of dead plants and animal material
what is functional diversity?
capacity to utilize a wide variety of substrates and carry out a wide array of processes
what is evenness in a community?
when no organism is likely to completely take over, caused by immense diversity
how is N2’s triple bond broken down?
with N-fixing bacteria that have an enzyme called nitrogenase
how does a peatland emit CO2?
- through the aerobic decomposition occuring above the water table
- through the oxidization of methane (methanotrophs) coming from the anoxic peat
which organism dominates decomposition processes in forest soil?
fungi!
what is the mutualistic relationship with plants and mycorrhizae fungi?
- plants supply the sugar for fungi
- fungus helps plant acquire nutrients and protects from pathogens and pests using antibiotic defense compounds
what do microarthropods do?
they can selectively influence the structure of a biological community by choosing what they feed on, they distribute microbial cells through the soil profile and their fecal pellets promote the formation of aggregates, improving the soil structure
what are detritivores?
organisms that eat detritus
why is having worms in soil not always a good thing?
invasion of earthworms leads to rapid stimulation of microbial decomposer activity and the release of a finite pool of nutrients at a rate too fast for trees to use
how do plants influence soil structure?
- primary agents for erosion control
- main contributors of organic matter
- large influence over general properties of soil (pH)
what is the rhizosphere>
area around plant roots
