water input vs output

Question 1

chart

Answer 1

input = output
precip Ecosystem (storage) -> evapotranspiration + runoff

Question 2

how is run off calculated

Answer 2

Runoff (R) = P – (ET + ∆𝑆)
P = precipitation
ET = evapotranspiration
∆𝑆= change in ecosystem

Question 3

what is run off affected by

Answer 3

1. Soil texture
2. Structure of soil (compaction)
3. Water capacity – runoff is higher in saturated soils, soil with less OM and soil with little
   compaction
4. Vegetation cover – increase in deforestation = stream flow increases; therefore, less trees,
   less transpiration, more runoff
5. Precipitation – increase precipitation, evapotranspiration is relatively steady (slight
   increase) but stream flow is directly proportional

Question 4

Human activities have substantially altered Earths hydrologic cycle - how?

Answer 4

Humans use about 50% of earths available renewable fresh water (in
terms on precipitation)
- Exceeds 100% in some dry regions
- Watershed: large spatial extent where topography and gravity suggest
the water will run to the lowest point and always to the ocean