Fundamental
concepts
Biology, Hydrology, and Social
Science
Setting the context: What is a watershed?

4 dimensional process
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Longitudinal:
upstream/downstream
Lateral: floodplain,
upland
Vertical: groundwater
zone/stream channel
Time: seasonality,
diurnal fluctuations
• System of intergration
- Network of streams
- Integrated systems and cycles
- Movement of flows; surface
and subsurface
- Mosaic of landcover, landscapes
and habitats
Watershed as a unit of analysis

Basic water planning and management unit
 Understand existing conditions

Historical range of variability (HRV)

International water law

New Zealand, South Africa

Nested spatial hierarchy
 Scale
Situational backdrop for analysis, cultural meaning,
experience, history, future
 Place-based: values and meaning

Problemshed
Defines both physical and social environment
 Goods, services, sinks, pathways, buffers, sense of place

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Integrated, individual based modeling framework
Physical
models
Social
models
Integrated
models
Biological
models
The Physical Setting
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
Climate
Geomorphology
Hydrology
Provides the template on which all
life is ultimately based.
Climate
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Measured over an extended period of time
Looks at averages, maximums, and minimums
Refers to the aggregate of temperature, humidity,
precipitation, winds, and cloud cover
Climate Influences
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Watershed vegetation
Communities
Stream flow magnitude and timing
Water temperature
Geomorphology

Study of landforms on the earth and
processes that change them over time

Fluvial Geomorphology

Refers to the structure and dynamics of stream
and river corridors
Hydrology

The science of water (in all its forms) as it relates to
the hydrologic cycle

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Distribution
Circulation and behavior
Chemical and physical properties
The hydrologic cycle is a life-sustaining cycle that is
a natural solar driven process of evaporation,
condensation, precipitation, and runoff.
Hydrologic Cycle
Physical Models of the Luquillo
Experimental Forest (LEF)
GIS based geomorphic model of LEF
streams
•

•
Rainfall, stream flow, channel attributes
Riparian vegetation & flow frequency
Analysis
- Relate streamside vegetation to the frequency of
flooding
GIS and GEOMORPHOLOGY
240 Sites
Grain Size
240 Sites
Cross-Section
Slope
Note the type of output that is typically used to understand the physical settings. We
tend to use graphs to communicate what is happening within an ecosystem.
Mean Annual
Rainfall (mm/yr)
4000
4000
3500
2500
S
RG
RB
P
C GB
NF
WF
RB4
EF
RBU
EV SF
0
400
600
800
ELEVATION (m)
1000
1200
RM2
3000
2500
2000
1500
200
RB1
3500
PE
EY
r2 = 0.90
2000
2.5
1000
200
DISCHARGE [m3/s]
LM
4500
RUNOFF (mm/yr)
RAINFALL (mm/yr)
5000
3000
Discharge (m3/s)
Runoff (mm/yr)
RF
RM1
RS
ES2
ES1RG1 ES3
r2 = 0.77
300
400
500
600
700
WEIGHTED AVERAGE ELEVATION (m)
800
2.0
ES2
RB1
ES3
1.5
RM1
RF
1.0
0.5
RS
ES1
0.0ES1
RG1
RG1
RM2
r2 = 0.97
0.0
0.5
1.0
1.5
2.0
2.5
3
PREDICTED DISCHARGE (WAE, DA) [m /s]
Modified from Garcia-Martino et al. (1996)
Precip = 2300 + 3.8Elev – .0016Elev2 n = 17, r2 = 0.91, p <0.001 (1)
Runoff = 4.26WAE + 360
n = 9, r2 = 0.77, p = 0.002 (2)
Discharge is estimated from runoff by multiplying by the drainage area:
Q = 3.17  10-5 A(4.26WAE + 360)
n = 9, r2 = 0.97, p <0.001 (3)
Grain size given drainage and
slope Channel Morphology
Headwaters - Volcaniclastic
1
Hack (1957)
This Study
Log (Slope (m/m))
0
S = .0060(GS/DA).59
-1
Headwaters - Granodiorite
S = .0068(GS/DA).57
-2
-3
-4
-2
-1
0
1
2
3
4
Log (Ratio, Median Grain Size(mm) : Drainage Area (sq. km))
Developing models of Channel habitat…
Identify critical habitats, barriers etc.
Downstream - Alluvium
2.5
Volcaniclastic
Elevation (m)
Elevation Profile
2.0
600
Elevation
Discharge
Granodiorite
1.5
400
1.0
Volcaniclastic
200
0.5
Alluvium
0
0.0
0
5
10
15
Mean Annual Discharge (m3 s-1)
800
20
Distance from Headwaters (km)
Channel Width,
Depth, Velocity
2.0
Width
Depth
Velocity
20
1.5
15
1.0
10
0.5
5
0
0.0
0
5
10
15
20
Distance from Headwaters (km)
Grain Size
Grain Size (mm)
2500
Estimated
Surveyed Data
2000
1500
1000
500
0
0
5
10
Distance from Headwaters (km)
15
20
Velocity (m2 s-1)
Width, Depth (m)
25
Channel
Features
Rainfall
Runoff
Stream
Energy
Riparian Vegetation and Bankfull Discharge
USGS Gage Surveys
-Transect from channel to banks
-Noted first occurrence of
vegetation type and corresponding
environmental variables:
Substrate
Soil
Litter
Canopy Cover
Vegetation Height
trees
mosses
herbs
shrubs
transect
grasses
Substrate fining
Soil development
Litter presence
Canopy shading
Vegetation height
Social
models
Physical
models
Integrated
models
Biological
models
The Biological/Ecological
Setting


Becomes established upon and integrated
with physical setting
Consists of all living organisms and their
interactions
Field Sampling
Trapping
Snorkeling
Electrofishing
Sampled 90 pools
and associated
riffles
The output typically
used to show species
distribution is much
more easily
communicated using
maps.
What factors influence the
distribution of each species?

Natural factors predict species distributions

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distance from ocean
location of waterfalls
pool complexity
percent fine sediments
Social
models
Physical
models
Integrated
models
Biological
models
The Social Setting

The template upon which people interact with
the natural environment is made up of the
physical and biological settings, both of which
influence how human and natural
communities coexist.
Social Models of Luquillo
Experimental Forest (LEF)
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Seasonal Visitor estimates
In and out of water recreation activities
Visitor Sampling Sites
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July and August 2005
weekdays, weekends,
and holidays
On-site interviews at 11
sites
Visitor counts in and
outside of rivers
Seasonal Visitor Estimates (Espíritu Santo River)
Day of the week
Weekday
Weekends
Holidays
Total
Visitors
2973
705
1646
5324
Number of Visitors for the Season (May-August 2006)
Espíritu Santo River
Number of Visitors
3000
2422
2500
2000
Visitors in the River
1500
1000
1041
551
500
Visitors Outside the River
605
479
226
0
Weekdays
Weekends
Day of the Week
Holidays
Note that different types of
graphs are used to
communicate the social
setting.
In addition, predictor
tables are used to show
factors influencing site
visits and return visitation
Seasonal Visitor Estimates (Espíritu Santo
River)
Percent of Visitors for the Season (May-August
2005)
Espíritu Santo River
120
Percentage
100
32
80
60
37
81
40
% Visitors in the River
68
63
Weekends
Holidays
20
0
19
Weekdays
% Visitors Outside the
River
Day of the Week
Seasonal Visitor Estimates (Mameyes River)
Day of the week
Weekday
Weekends
Holidays
Total
Visitors
6666
2255
3806
12727
Number of Seasonal Visitors (May-August 2005)
Mameyes River
Number of Visitors
4000
3500
3700
2966
3000
2441
2500
2000
1500
11981057
1365
1000
500
0
Weekdays
Weekends
Day of the Week
Holidays
Visitors in the River
Visitors Outside the
River
Seasonal Visitors Recreating in the Water
by Day of the Week Espíritu Santo River
(May-August 2005)
Number of Visitors
Seasonal Visitors Recreating in the Water by Day of the Week
Espíritu Santo River (May-August 2005)
800
700
600
500
400
300
200
100
0
Holidays
Weekends
Weekdays
El Verde
Jimenez Jimenez Falls Sonadora
Bridge
Site
Waterfall
Seasonal Visitors Recreating out of the Water
by Day of the Week Mameyes River (MayAugust 2005)
Seasonal Visitors Recreating Out of the Water by Day of the Week
Mameyes River (May-August 2005)
Number of Visitors
7000
6000
5000
4000
Holidays
Weekends
Weekdays
3000
2000
1000
0
Angelito Juan Diego La Mina
Trail
Site
La Vega
Puente
Roto
Predictor Variables of Repeat Visitor Use
on the Rio Mameyes & Espíritu Santo
Factors influencing Repeat Visits
Positive & Significant
Negative & Significant
Road Width (+)
Travel Cost (-)
Waterfall (+)
Streamflow (+)
Medium pools (+)
Trash Cans (+)
Picnic Tables (-)
Small Pools (-)
Formal trails (-)
Restaurants nearby (+)
 Any
Questions?
Characteristics of Complexity

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Nonlinear or chaotic behavior
Interactions that span multiple spatial and temporal scales or
levels
Unpredictable behavior (hard to predict)
Hierarchical structure, scalable
Self organization
Emergent properties
Adaptive Behavior
Cascading effects
Must be studied as a whole, as well as piece by piece
Relevant for all kinds of organisms in all kinds of
environments
Surprise: Natural Disasters; unintended consequences of
human behavior