Week 4 Flashcards
what is the foundational unit of matter
atoms. they are the smallest unit to exhibit characteristic of an element
what is a molecule
2 or more atoms joined together
what are the 4 coumpunds that make up life
carbs
fats
protein
nuc acid
what are the sates that matter can exist
solid, liquid and gas
what is a biogeochemical cycle
the continuous cycling of nutrients found within the ecosphere
may either be gaseous or sedimentary
what is nitrogen
N2 is a tasteless, colorless and odorless gas required by all orgs
what is the nitrogen cycle
1) fixation: turning N2 into NH3 or NH4+ by bacteria (Rhizobium Family) or lightning
2)nitrification by chemotrophic bacteria (biological) of NH4+ into NO2- and NO3, which is used by plants
rather instead of fixation, N2 for dead organic matter can be converted into NH4 through ammonification
why is nitrogen important
the amount of nitrogen within a system impacts the systems biological and ecosys processes
what is denitrification
the conversion of nitrates into N2 by anaerobic bacteria
in what form is carbons mostly stored as
CO2
what is the C cycle
1) carbon is consumed by animals
2) co2 from respiration
3)co2 uptaken by plants with sun and h2o
4) o2 is produced
when animals or plants die the co2 in their bodies are decomposed and co2 is returned to the atmos
how can C be stored in the earth?
when particular conditions are met. usually encompassing very oxygen-depleted areas (peat bogs) where decomposition cannot readily take place. the matter may be carried rapidly as well which preserved structures
how much of earth’s surface is comprised of water?
71% where 97% is ocean and 3% is fresh
which spheres does the water cycle travel through
atmosphere
lithospere
bioshpere
where is water stored
lithosphere (ground water and aquifers)
lacks
oceans
glaciers
what is the water cycle
1) precipitation
2) runnoff (if on land)
3) evaporation or transpiration
4) condensation
how much water is precipitated onto land? oceans?
24%=land
76%=oceans
how much water is evap from land? oceans?
14%=land
86%= oceans
what is the residence time
the rate at which molecules move through a hydrological system. (measured in time)
active movement = river= short
in a reserviour= glacier or ocean= long
what is precipitation
the solid or liqud form of water that forms under saturated conditions and falls to earth once at 100% humidity
what is required for precipitation to occur?
condensation nuclei
saturation cooling by uplift
what are condensation nuclei
small particles that provided the foundation for water droplet formation. water vapor condenses around these particles to form clouds
what are the mechanisms that lift water
1) Frontal/ convergence
2) orographic
3) radiative cooling
4) Convectional
what is orographic uplift
the movement of water from a low elevation to a high elevation, forced by topography of a region.
this results in adiabatic cooling of the gas pocket until 100% humidity is reached
what si the dry lapse air rate? moist air lapse rate? which is fatser?
DALR= 10 per km
MALS= 6 per km
Moist is faster
what is the lapse rate
the decrease in the temperature of an air parcel as it increases in elevation
leeward side vs windward side
leeward side is on the other side of the geographical feature, wind is generally warmer as the cloud passes over
the windward side is the side of a topographical feature that the water body resides on. wind is generally cooler
what is a rain shadow and why does it happen
it is the reduction of rainfall on the leeward side of a topographical feature due to the shelter it provides. I’m contrast the windward side generally emperors much more rain fall.
what is frontal lifting
the displacement of warm moist vs cool dry air when 2 wind forces meet
here the warm wind is forced upward and cools to its dew point. this is common along the equatorial zone of the earth
what is convective lifting
the rising of air due to the heating of the ground by the sun, causing it to rapidly rise to meet its dew point
this type commonly gives rise to short and intense thundershowers
what is radiative cooling
the cooling of the earth surface which causes air to cool and condense as well near the surface
what is rain
liquid precip that falls to earth with a diameter greater than 0.5mm but less than 5mm
what is freezing rain
the resulting precipitation when he atmosphere is above ) but the surface is below 0, ice forms when rain hits the surface
what is sleet
transparent ice pellets less than 5mm. this is due to the atmosphere being above 0, but the rain drops are able to freeze before hitting the ground
what is snow
ice crystals that form on condensation nuclei. the atmosphere must be below 0
what is hail
frozen ball of precipitate caused by strong updrafts. these balls are commonly greater than 5mm
what is a sedimentary cycle
the mobilization of materials that are sourced from the lithosphere by geological uplift. generally, these nutrients will travel through the hydro, possibly atmos back to the lith
phosphorous
a macronutrient that exists in solid particulate form and is a critical component to metabolic function.
bc this nutrient is sourced from the lithosphere, regeneration by weathering is limited, therefor it stays in tight circulation/ storage of the biomass above ground.
what is the dominant limiting factor in freshwater ecosystems and terrestrial plant growth
phosphorous
what influences the availability of phosphorus in soil?
the pH. it is unavailable (insoluble in groundwater) at either very high or very low pH (less than 5.5 or greater than 7)
what is guano
a biological source of phosphorous in the form of bird droppings, which act as fertilizer
sulphur
an essential macronutrient that is a necessary component to proteins
may exist in solid or gaseous forms and requires to be converted into many different forms to be available
what dictates the form of sulfur in soil
the presents of oxygen and the types of metal ions that are present. inorganic sulphur (sulfates) are readily uptaken by plants
how do humans perturbation the biogeochemical cycles
we synthetically produce or extract minerals that are useful, commonly for agricultural uses.
commonly the nuties that are of interest are N, P, and K.
what is cultural eutrophication, and what is the main cause?
the excessive growth of algae due to the surplus of agricultural minerals in bodies of water by runoff from HUMAN SOURCES.
may either by point sourced(sewage) or diffuse(farming)
what is an oligotrophic system
an ecosystem devoid of nutrients, such as dissolved salts. This leads to an area with minimal growth high oxygen and lo organic material.
what is the consequence of eutrophication
a surplus of P and N especially (sed min) causes algal blooms and suffocates aquatic ecosystems.
