NR 504 Final Exam
Nutrients – answer Defined as an element or compound needed for growth and/or
survival
Macronutrients – answer nutrients needed in large quantities; Nitrogen (N),
Phosphorous (P)
Micronutrient – answer Nutrients needed in small amounts (e.g. vitamins, minerals like
K, Ca, Mg, zinc, iron)
Importance of Nitrogen - answerA major constituent of amino acids; The fourth most
abundant element in living cells behind C,H, and O; Molecular nitrogen = N2(78 % of
atmosphere); Ammonium = NH4(immobile in soils); Nitrate = NONitrate = NO33-(Highly
mobile in soils); Most common GW contaminant; Organic N(N assimilated into biomass
or detritus); Nitrous oxide = N2O(Important greenhouse gas)
Biogeochemical cycle - answer nutrients moving from the environment to organisms
back to the environment
N Cycle Driven by - answerthe water cycle, biological nitrogen uptake, oxygen levels,
and bacteria
Nitrogen Fixation - answerConverts N2 to plant usable form(requires much energy)
Ammonification - answerOrganic N converted to inorganic form (NH4) during
decomposition
Assimilation - answerUptake of inorganic N into biomass by Primary producers and
Bacteria
Nitrification - answerMicrobes get energy from the ammonium (chemoautotrophs), Use
this energy to synthesize organic carbon from CO2, N becomes more mobile in the
environment as NO3-
Denitrification - answerA microbial process that Returns N to atmosphere, N2O is a side
product and is major greenhouse gas (i.e. this is not good)
Point Anthropogenic Sources of 'bioactive' - answerWastewater effluent
Nonpoint Anthropogenic Sources of 'bioactive' - answerUrban runoff, Septic fields,
Agricultural, Manure, Lawns, Atmospheric deposition
, Phosphorous Importance - answerAn essential component of DNA, Cell membranes;
An essential component of energy transport in cell (ATP); Needed in much smaller
quantities than C, H, O, and N
Phosphorous Sources - answerNO ATMOSPHERIC SOURCE!, P-containing rocks
(ultimate source), Fertilizers (originate from P-containing rocks), Plant organic matter,
Municipal and industrial wastes, Detergents (formerly - no more), Erosion - sediment-
bound P
Phosphorous Cycle - answerDissolution --> Assimilation --> Mineralization -->
Sedimentation --> Lithification
Dissolution - answerweathering of rock, OR desorption from sediments (anaerobic)
Mineralization - answerorganic to inorganic, Release from biomass
Sedimentation - answerthe settling of P sorbed to particles. Sorption occurs when oxic
Lithification - answersediments compact back to rock
Consequences of Phosphorous Loading - answerNo known DIRECT human health
effects; Tends to limit nutrients in freshwater systems; algal blooms result if have
enough light
Source Management - answerDelineate P Source Area - Typically 90% of the P is from
10% of the watershed; Control P at its source
Landscape Management - answerChange how water flows through the watershed,
examining impervious surface, agriculture, and discharges to surface waters (convert
stormwater to groundwater; buffers)
Oligotrophic - low productivity - answer
Mesotrophic - moderate productivity - answer
Eutrophic - high productivity - answer
Eutrophication - answerPhysical, chemical, and biological changes take place when a
water body receives increased inputs of nutrients (mainly N and P) from natural
processes such as erosion and runoff, which accumulate in bottom sediments.
Sources of Cultural Eutrophication - answerDischarge of untreated municipal sewage,
Nitrogen compounds produced by cars and factories, Discharge of detergents
(phosphates), Natural runoff (nitrates and phosphates), Manure runoff from feedlots,
Inorganic fertilizer runoff, Discharge of treated municipal sewage, Runoff from streets,
lawns, and construction, Runoff and erosion, The dissolving of nitrogen oxides
Nutrients – answer Defined as an element or compound needed for growth and/or
survival
Macronutrients – answer nutrients needed in large quantities; Nitrogen (N),
Phosphorous (P)
Micronutrient – answer Nutrients needed in small amounts (e.g. vitamins, minerals like
K, Ca, Mg, zinc, iron)
Importance of Nitrogen - answerA major constituent of amino acids; The fourth most
abundant element in living cells behind C,H, and O; Molecular nitrogen = N2(78 % of
atmosphere); Ammonium = NH4(immobile in soils); Nitrate = NONitrate = NO33-(Highly
mobile in soils); Most common GW contaminant; Organic N(N assimilated into biomass
or detritus); Nitrous oxide = N2O(Important greenhouse gas)
Biogeochemical cycle - answer nutrients moving from the environment to organisms
back to the environment
N Cycle Driven by - answerthe water cycle, biological nitrogen uptake, oxygen levels,
and bacteria
Nitrogen Fixation - answerConverts N2 to plant usable form(requires much energy)
Ammonification - answerOrganic N converted to inorganic form (NH4) during
decomposition
Assimilation - answerUptake of inorganic N into biomass by Primary producers and
Bacteria
Nitrification - answerMicrobes get energy from the ammonium (chemoautotrophs), Use
this energy to synthesize organic carbon from CO2, N becomes more mobile in the
environment as NO3-
Denitrification - answerA microbial process that Returns N to atmosphere, N2O is a side
product and is major greenhouse gas (i.e. this is not good)
Point Anthropogenic Sources of 'bioactive' - answerWastewater effluent
Nonpoint Anthropogenic Sources of 'bioactive' - answerUrban runoff, Septic fields,
Agricultural, Manure, Lawns, Atmospheric deposition
, Phosphorous Importance - answerAn essential component of DNA, Cell membranes;
An essential component of energy transport in cell (ATP); Needed in much smaller
quantities than C, H, O, and N
Phosphorous Sources - answerNO ATMOSPHERIC SOURCE!, P-containing rocks
(ultimate source), Fertilizers (originate from P-containing rocks), Plant organic matter,
Municipal and industrial wastes, Detergents (formerly - no more), Erosion - sediment-
bound P
Phosphorous Cycle - answerDissolution --> Assimilation --> Mineralization -->
Sedimentation --> Lithification
Dissolution - answerweathering of rock, OR desorption from sediments (anaerobic)
Mineralization - answerorganic to inorganic, Release from biomass
Sedimentation - answerthe settling of P sorbed to particles. Sorption occurs when oxic
Lithification - answersediments compact back to rock
Consequences of Phosphorous Loading - answerNo known DIRECT human health
effects; Tends to limit nutrients in freshwater systems; algal blooms result if have
enough light
Source Management - answerDelineate P Source Area - Typically 90% of the P is from
10% of the watershed; Control P at its source
Landscape Management - answerChange how water flows through the watershed,
examining impervious surface, agriculture, and discharges to surface waters (convert
stormwater to groundwater; buffers)
Oligotrophic - low productivity - answer
Mesotrophic - moderate productivity - answer
Eutrophic - high productivity - answer
Eutrophication - answerPhysical, chemical, and biological changes take place when a
water body receives increased inputs of nutrients (mainly N and P) from natural
processes such as erosion and runoff, which accumulate in bottom sediments.
Sources of Cultural Eutrophication - answerDischarge of untreated municipal sewage,
Nitrogen compounds produced by cars and factories, Discharge of detergents
(phosphates), Natural runoff (nitrates and phosphates), Manure runoff from feedlots,
Inorganic fertilizer runoff, Discharge of treated municipal sewage, Runoff from streets,
lawns, and construction, Runoff and erosion, The dissolving of nitrogen oxides
