Term
| where is surface water found? |
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Definition
above ground in streams, lakes, and wetlands
surface water and groundwater are connected, water flows between them |
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Term
| how do streams interact with groundwater? |
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Definition
1. water moves from the stream to the groundwater
2. water moves from the groundwater to the stream
3. water moves back and forth between the stream and groundwater and different points along a stream reach or at different times |
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Term
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Definition
water moves from the groundwater into the stream
the water table slopes down toward the stream, and the stream discharge increases downstream |
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Term
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Definition
the water moves from the stream to the groundwater. the water table slopes away from the stream, and the stream discharge decreases downstream
in some cases the losing stream is completely disconnected from the water table |
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Term
| explain temporal variations in groundwater-surface water exchange. |
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Definition
streams alternate between gaining or losing to the groundwater system over time or in space
over time: stream level (stage) rises and falls
during periods of rising stage, water may seep from the stream into the banks of the channel, making it a losing stream
when level (stage) falls, the water stored in the banks lining the channel seeps back into the stream making it a gainging stream. |
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Term
| explain spatial variations in groundwater-surface water exchange (the hyporheic zone) |
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Definition
water moves in and out of channel bed and banks along a reach of the channel
ex: water will take underground route accross a flow bend or will flow in the subsurface down a steep channel section (riffle)
these along-channel interactions take place in a region called hyporheic zone = region beneath and adjacent to a stream bed where stream water flows and mixes with groundwater
it differs in chem and bio character from most groundwater and stream water
flow rates in this zone are greater than in most groundwater systems, so the supply of nutrients is greater than in groundwater
moreover, the pore space w/in the sand or gravel of a riverbed provides a more physically protected environment than the stream channel
for these reasons, the hyporheic zone = important habitat for microbes, larvae, fish, spawning etc |
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Term
| How does growndwater-surface water exchange influence the movement of the pesticide atrazine from a stream channel to bank sediments and back into the stream channel over a period of months? |
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Definition
it prolongs the time when atrazine is detected in the river water
it contaminates groundwater, moves through river and back into ground water and around and around, it takes ages to flush out |
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Term
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Definition
| areas saturated by surface water or groundwater at a frequency and duration sufficent to support a prevalence of vegetation adapted for saturated soil conditions |
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Term
| what is a groundwater fed wetland? |
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Definition
| a wetland that is more nutrient rich, since the water coming into the wetland has interacted with soil, sediment and vegetation, picking up solutes before entering the wetland |
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Term
| what is a precipitation fed wetland? |
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Definition
| like a losing stream, a source of water to the groundwater. this type of wetland is likely to be nutrient-poor, since the water source is rain that has not intercted with rocks and soil |
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