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Watersheds and the Hydrologic Cycle

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Page 1: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Watersheds and the Hydrologic Cycle

Page 2: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

The Global Hydrologic Cycle

Page 3: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Water Cycle in Florida

Page 4: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Florida Water Facts• Surface Area = 170,452 km2

• Average Rainfall = 140 cm (55”)– Total Annual Rain = 238 billion m3 (62.6

trillion gallons)

• River and Stream = 51,858 miles• Largest River = Apalachicola (Q =

25,000 ft3/s = 22 km3/yr)• Lake Area = 12,100 km2

• Springs ~ 8 billion gallons/ day• Groundwater supplies 95% of water

– 7.2 billion gallons/day; 80% to S. Florida• Low relief – travel time for water

(rainfall to sea) can be decades

Page 5: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

The Hydrologic Check-Book• Mass Balance

– Water mass is conserved– Therefore: Water In = Water Out

• Sources– Rain, Snow, Groundwater, Human Effluent

• Sinks– Ground, River, Atmosphere, Humans

• Stores– Wetlands, Lakes, Rivers, Soil, Aquifers

Page 6: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

The Water Budget (Exam 1)

P= Q + ET + G + ΔSPrecipitation

Surface runoff

Evapotranspiration

Groundwater

Storage

INFLOW OUTFLOW

Page 7: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Rainfall (~ 140 cm)

Infiltration to Deep Aquifer (~5 cm, though upto ~ 40 cm)

Subsurface Runoff (~ 32 cm)

Interception (~ 30 cm)

Transpiration(~ 70 cm)

Annual Water Budget - Flatwoods

Surface Runoff (~ 3 cm)

Page 8: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Rainfall (~ 140 cm)

Infiltration to Deep Aquifer (~5 cm, in areas much higher)

Interception (~ 15 cm)

Transpiration(~ 80 cm)

Annual Water Budget – Ag Land

Surface Runoff (~ 20 cm)

Subsurface Runoff (~ 20 cm)

Page 9: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Rainfall (~ 140 cm)

Infiltration to Deep Aquifer (~ 2 cm)

Interception (~ 20 cm)

Transpiration(~ 50 cm)

Annual Water Budget – Urban Land

Surface Runoff (~ 60 cm)

Subsurface Runoff (~ 5 cm)

Page 10: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

In > Out ?

Out > in ?

In = Out ?

What if Inmeasured > Outmeasured

AND water level is falling?

Changes in Internal Stores• ΔStorage = Inputs – Outputs

– Usually easy to measure (e.g., lake volume)

Page 11: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Volume = Depth x AreaDepth = Volume / Area

Rules of Water Balances• Water balance terms must be in common units

– (usually meters depth over the watershed area).

• Precipitation and ET measured in depth (m/yr)• Water flows measured as volumes (m3/yr).

Page 12: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

An Even Simpler Water Budget• Budyko Curve shows annual catchment hydrology

– Can neglect G and ΔS, focus on ET (P ~ ET + Q)– Aridity index on the x-axis (potential ET:rain)– Evaporative index on the y axis (actual ET:rain)

Page 13: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Catchment Water Balance• Area = 100 ha (10,000 m2 per ha)• Annual Measurements:

– Rainfall = 2 m (tipping-bucket rain gage)– Surface outflow (Q) = 20,000,000 m3 (weir)– ET = 1.5 m (evaporation pan)– Groundwater = 10,000,000 m3 (shallow wells)– Assume ΔS=0

Page 14: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Budget: P= Q + ET + G + ΔS• Area = 100 ha; 1 ha = 10,000 m2

• P = 2.0 m• Q = 20,000,000 m3/(100 ha * 10,000 m2/ha)

= 0.2 m• ET = 1.5 m• G = 10,000,000 m3/(100 ha * 10,000 m2/ha)

= 0.1 m• ∆S = 0

• 2.0 = 0.2 + 1.5 + 0.1 + 0 (?!)

Page 15: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Watersheds

• A land area from which all rainfall drains to the same point.– The “watershed” is technically the divide between

two such areas (called basins)

Page 16: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Delineating Watersheds1. Identify

outlet point2. Identify

high points3. Link high

pts crossing contour lines at right-angles

1

23

Page 17: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

High-Relief Watersheds

Page 18: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Why Watersheds?

• Control boundaries– Water that falls either comes out the bottom or is

abstracted

• Imagine a water budget if you weren’t sure where the water was going…

P + Qin1 + Qin2 = Qout1 + Qout2 + ET + G1 + G1+ ΔS

Page 19: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Experimentation – Paired Watersheds• What is the

effect of forest management on:– Water yield– Sediment yield– Nutrient export– Water

temperature– Time of

transport

Page 20: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Paired Watershed Response

Page 21: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Paired Watershed Study of Forest Harvest Effects on Peakflows

Beschta et al. 2000 – H.J. Andrews Experimental Forest (OR)

LOGGING ROAD BUILDING

Page 22: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Does watershed delineation work in Florida?

• Low-relief– Delineation of boundaries

hard– In parts of Florida, water

flows depend on:• where it rained, • where the wind is blowing

and • where people put the

canals and roads

• National contour maps too coarse (5 ft)

• Roads act as flow delineators

????

Page 23: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

“Delineating” Watersheds in

Florida

Page 24: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Paired Watersheds in Florida

• Shown that (Riekerk 1983):– High intensity logging increased water yields by

250%– Low intensity logging increased water yields 150%– Clear cutting altered nutrient export rates– All forest operations (fire?) were less than

urbanization (much more on this later)

Page 25: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Stream Patterns

• Dendritic patterns follow Strahler Order– 1st order is unbranched– 2nd order occurs when two

1st order reaches converge– Increased order requires

convergence of two reaches of the same order

– What are springs?

Page 26: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Network Forms

• Regional landform dictates shape

• Regional geology dictates drainage density

• Regional climate (rainfall) dictates density and maturation rate

Page 27: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Stream Order Distribution

Page 28: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Watershed Networks

• Mass transport is optimal at minimum work– Reach and network scales at the

SAME time

• Necessary conditions for dendritic drainage– Minimal energy expenditure at

any link in the network– Equal Energy Expenditure per

unit area– Minimum Energy Expenditure in

the Network as a whole

Rodriguez-Iturbe et al. (1992) - WRR

Page 29: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Water Convergence Across Scales

- St Johns River Basin- Ocklawaha River Basin

- Orange Creek Sub-Basin- Newnans Lake Watershed

- Hatchett Creek Watershed- ACMF “Hillslope”

- Lake Mize catchment

Presenter
Presentation Notes
il
Page 30: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Lake Mize hillslope Lake Mize

Conference Center

Page 31: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Austin Cary Forest

HatchettCreek

LakeMize

Page 32: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Hatchet Creek Catchment

HatchettCreek

Page 33: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Newnans Lake

WatershedNewnans

Lake

Gainesville

Santa FeSwamp

HatchettCreek

Lake ForestCreek

PrairieCreek

Page 34: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Orange Creek Basin

NewnansLake

LochloosaLake

OrangeLake

PaynesPrairie

Page 35: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Ocklawaha RiverBasin

Orange CreekBasin

LakeApopka

RodmanReservoir

Ocklawaha River

SilverSprings

Page 36: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

St. Johns River Basin

(and Water Management

District)St. Johns River

Page 37: Watersheds and the Hydrologic Cyclesfrc.ufl.edu/ecohydrology/FWR/Lecture2_2017.pdf · Hydrologic Cycle. The Global Hydrologic Cycle. Water Cycle in Florida. Florida Water Facts

Next Time…

• Precipitation– Where it falls– When it falls– How it’s made– How we

measure it