Groundwater and Lakes Flashcards
Movement of Groundwater
- Precipitation infiltrates the subsurface materials
- moves through vadose zone to zone of saturation
boundary between vadose and saturation zone is called water table - as water enters vadose zone its chemical composition changes due to additions of organic material and soluble salts
- as water moves through groundwater, oxygen is consumed by oxidation of dissolved organic carbon
Vadose zone
zone in which the pores are not completely filled with water
Saturated zone
zone in which the pores are completely filled with water
Water interaction with aquifer rocks, Mesilla Basin New Mexico and Texas
Piper Diagrams
- bottom left triangle: Cations–> Ca, Mg, and Na/K
- Bottom right triangle: Anions–> SO4, HCO3, Cl
- Top triangle: summarizes the bottom 2 triangles
Epilimnion
Well-mixed surface layer
change in amount of the substance in the epilimnion over time = CiFi +ChFh-CoFo-CeFe-Rpe
where Ch is concentration in hypolimnion
Rpe= the rate of removal of the substance by particles in the epilimnion
Thermocline
zone of rapidly decreasing temperature
Hypolimnion
Well mixed deep layer
WInter Lake mixing
surface layer reaches 4C, the temp for maximum density
- dense surface waters sink and deeper waters brought to surface
-density stratification
-temp increases slightly with height
Summer lake mixing
surfaces warm to 4C and
Conservative behaviour
Occurs when the variations in concentrations of a substance can be described by simple mixing
Non-conservative Behaviour
Occurs when the concentration of a substance can be affected by processes other than simple mixing (chemical and biological Processes)
Equation for amount of substance stored in sediment
Rs=Rpe+Rph-Rd
Rd= rate of re-solution of the substance
Rph = rate of removal of the substance by particles in the hypolimnion
