Freshwater

Lake Classification Trophic system More Eutrophic Mesotrophic Oligotrophic Dystrophic More Fish, size, closed or fed, etc.

Freshwater Chemistry Total amount of ions called TDS Cations Mg+2 17% Na+ 15% K+ 4% When Ca and Mg is high called hardwater lake due to high buffering capacity called softwater when low The low calcium within Lake Superior is making it more resistant to zebra mussel invasion

Freshwater Chemistry Anions HCO3- 73% SO4-2 16% Cl- 10% Best understood ion is hydrogen ion due to it determining pH Average lake pH is about 7.2 Average lake pH is about 7.4

Acid Acid Caused by the excessive amounts of sulfur and nitrogen released by cars, industrial processes, or volcanoes Dry-sticks to dust or stays around with smoke Wet-any form which removes the acid from the surface and deposits it on Earth’s surface Kills many smaller fish and eggs in lakes due to them not being able to tolerate large differences in pH Mercury can also be carried in acid rain and be transferred to fish crating the possibility of mercury poisoning

Lake Physical Properties Can become salt water if it has no way no remove water Water carries minerals Nothing carries minerals away 98% of all accessible surface water is contained in lakes Due to solid form of water being less dense whole lakes won’t freeze solid

Our effect on Lakes Valuable to us for Pollution Trade routes Irrigation Drinking water Climatic control Hydro-electric energy Pollution Point- able to trace back to origins Nonpoint- not able to trace back to origins

Human impact on lakes Damming Invasive species Pollution Downstream destruction Upstream flooding Invasive species Disrupts local ecology Pollution Kills organisms

River geography Most sediment deposition occurs in plains Most have a delta at the end of the river where the river srivers plits into many channels and deposit sediment The goal of the river is to create a wide flat valley to flow to the ocean When a river meets the ocean or sea they form estuaries Meanders are constant bends in rivers

Human impact on rivers Levees Pollution The flooding of plains deposit nutrients which allow flood plains to flourish Levees prevent these flood plains from receiving their nutrients Levees also cause the flooding to happen somewhere else either up or downstream Pollution Rivers are also effected by point and non-point pollution Though much of the pollution is downstream rather then upstream

Groundwater http://earthguide.ucsd.edu/earthguide/diagrams/groundwater/index.html Overuse of groundwater is called overdraft Problem in arid areas for running out of water Also problem in hyporheic zones Pollution Very susceptible to pollution Subsidence The deflation of land due to the decrease of hydraulic pressure underground

Icebergs and sea ice An iceberg is a floating piece of ice which has broken or calved off of a glacier An iceberg has 90% of it’s mass underwater Ice types Pancake ice- round slushy ice which is 30cm to 3m in diameter Brash ice- accumulation of floating ice no more then 2m across, wreckage of other ice Ice cake- any flat piece of ice less then 20m across Polynya- an area of open ocean surrounded by sea ice

Sea ice Grease ice- very thin soupy layer of clumped frazil ice Frazil ice- a collection of loose needlelike ice Fast ice- ice which forms and is attached to the coast Ice floe-any flat piece of ice 20m or more across Small 20-100m Medium 100-500m Big 500-2000m Vast 2-10km Giant >10km