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70-90% of world's reliable water by 2025


70% of water withdrawn from rivers, lakes and aquifers is not returned

what is the biggest user of water?


what is the second biggest user of water?

industry (20%)

what is the third biggest user of water?

cities and residence (10%)

where does most of the world's photosynthesis take place?

0-200 meters below the surface, 40% low nutrient level, high dissolved oxygen

Thermal Stratification

temperature differences in deep lakes with warm summers and cold winters


equalizes temperature at all depths (spring and fall) also brings oxygen to the bottom and nutrients to the top


middle layer of water that acts as a barrier to the transfer of nutrients and dissolved oxygen; results in a loss of oxygen at lower levels and a loss of nutrients at upper levels

Inland wetlands:

act as natural sponges and absorb excess water and wildlife habitats; filter and degrade pollutants, reduce flooding and erosion, replenish stream flows, recharge ground aquifers, provide economic resources and recreation


temporarily flooded, often silty land next to a river or lake


lowland region permanently covered with water

hardwood bottom land forest

an area by a river or stream where lots of hardwoods grow (oaks)


where freshwater and saltwater meet, partly surrounded by land with access to open ocean and a large supply of freshwater from a river


salt level of the water that fluctuates with tidal cycles, time of year, and precipitation

estuary fertility/productivity

most fertile ecosystem in the world and most productive; nutrients from land to river are transported to the estuary, tidal action circulates nutrients and removes waste, lost of light, plants provide photosynthetic carpet

salt marshes

ground is saturated and there is little oxygen (decay takes place slowly) , lots of invertebrates and is the breeding ground for some ocean animals and has a surface inlet and outlet

mangrove forests

located on tropical coasts where there is too much silt for coral reefs, dominated by mangrove trees (salt tolerant trees, 55 species), protects the coastline from erosion and acts as a nursery for some 2000 species of plants, invertebrates, and fish

sea grass beds

flowering plants that have adapted to complete submersion in salty water found in quiet, shallow, temperate,tropical and subtropical water, up to depths of 10m if the can photosynthesize

ecological importance of sea beds

reduce surface erosion, provide food and habitats

Ogallala Aquifer

world's largest known aquifer, 1/4 depleted by 2020


75% of world's commercially valuable fish are over fished or close to sustainable limits, needlessly throwaway 30% of catch

Individual Transfer Rights (ITR)

gov't gives private owners a % of the TAC (total allowable catch)

problems with ITR

Essentially transfers ownership of public waters to private owners; Smaller companies with less capital can be pushed out of the marketplace; TACs can be set too high to prevent overfishing

Gravity flow irrigation

60-80% effective water reaches plant roots and is taken up by plants

center pivot/ low pressure sprinkler

80% effective, more with LEPA sprinkler

drip/trickle (micro-irrigation)

90-95% effective, expensive to install, most effective and best at reducing water waste

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