The Cape Fear River
•
Chemical and Physical
Analysis of the Cape Fear
Estuary
The Cape Fear River
(CFR), the most
industrialized of all
North Carolina’s rivers,
winds for over 200
miles through the heart
of the piedmont,
crosses the coastal
plains, and empties into
the Atlantic Ocean just
south of us near
Southport.
What we measured
•
•
•
•
•
•
Meteorology
Flow
Temperature
Salinity
Turbidity
Light Attenuation
• Chlorophyll
• Dissolved Organic
Carbon
• Dissolved Oxygen
• pH
• Nutrients
Station
HB
M61
M54
M42
M35
M23
M18
Miles from sea
24.54
21.02
17.24
13.79
9.89
3.54
0
1
Raymond Gephart
• MS Chemistry
Turbidity/Meteorology
September Winds
18
Turbidity meter
Wind Speed (mph)
16
14
*
12
10
8
6
4
2
25
29
23
27
19
21
13
15
17
7
9
11
3
5
1
0
Day
October Winds
18
14
12
10
8
6
31
19
21
23
13
15
17
7
9
11
3
5
1
0
29
2
25
*
4
27
Wind Speed (mph)
16
Day
Turbidity - Cruise 1
250
Turbidity (ntu)
27
29
21
^
25
23
15
17
^*
19
9
11
13
5
3
* = cruise
7
200
^
1
Precipitation (inches)
September Precipitation
2
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
Day
^ = trace precipitation
October Precipitation
2
150
Surface
Deep
100
1.6
1.4
50
1.2
1
0.8
0.6
0.4
0
M18
M23
M35
M42
M54
M63
HB
31
Station
27
*
29
21
^
23
^
19
15
17
11
13
9
3
5
7
0
25
0.2
1
Precipitation (inches)
1.8
Day
2
Surface Turbidity
Turbidity - Cruise 2
140
250
120
200
Surface
Deep
100
Turbidity (ntu)
Turbidity (ntu)
100
150
80
2004
2002-2003 Average
60
40
50
20
0
M18
M23
M35
M42
M54
M63
0
HB
M18
Station
M23
M35
M42
M54
M63
HB
Station
Deep Turbidity
Conclusions
140
120
Turbidity (ntu)
100
80
2004
2002-2003 Average
60
40
20
0
M18
M23
M35
M42
M54
M63
• Cruise 1 had higher turbidity than Cruise 2
which could be a result of the faster winds
and greater precipitation before the
cruises.
• The deep turbidity was higher than the
surface turbidity.
• This year’s turbidity was higher, especially
for the deep water, than the average from
the past couple years.
HB
Station
CTD Data
• The CTD measures
temperature, conductivity
and pressure.
• The salinity was calculated
from the temperature and
conductivity measurements,
using the practical salinity
scale from 1978.
3
Salinity Data Cruise 1
• Water Temperature: Temperature is
a good example of thermal
stratification within the water column.
High water temperatures (35 degrees
Centigrade and above) can be
harmful to the aquatic life.
• Salinity: This is a good indicator of
the vertical stratification within the
water column. It also depicts any
fresh water runoff as well as the tidal
penetration of seawater.
0
1
2
3
4
5
6
0
4
10
13
17
Temperature Data Cruise 1
0
1
2
3
4
5
6
Depth (meters)
7
8
9
10
11
12
13
30-35
25-30
10
20-25
15-20
10-15
5-10
0-5
11
12
0
4
10
13
17
21
0
4
10
13
17
21
13
Salinity
0-5
21
Distance (miles)
4
9
10-15
5-10
3
8
15-20
13
2
Depth (meters)
20-25
12
1
7
25-30
9
11
0
6
30-35
8
10
Salinity Data Cruise 2
5
Depth (m)
7
24
25-25.5
24.5-25
24-24.5
23.5-24
23-23.5
22.5-23
22-22.5
21.5-22
21-21.5
20.5-21
20-20.5
19.5-20
Distance (miles)
Distance (miles)
Temperature Data Cruise 2
Stow Away Tidbit Temp Logger
12
10
8
6
4
2
0
4
10
13
17
21
24
0
Depth (meters)
25.00-25.50
24.50-25.00
24.00-24.50
23.50-24.00
23.00-23.50
22.50-23.00
22.00-22.50
21.50-22.00
21.00-21.50
20.50-21.00
20.00-20.50
19.50-20.00
•
•
•
•
Eulerian measurement of temperature
Deployed at mid-depth from 9/20/04-10/25/04
Lat. 34°05.47N, Long. 77°55.93W
Captured
temperature data
at 15 minute
intervals
Distance (miles)
4
Daily Tem p Flux
24.5
24
23.5
Temp
23
22.5
22
21.5
9/
21
/
9/ 200
21 4
9/ / 20 0:0
21 04 3
/2 1
9/ 00 :1
21 4 8
9/ / 20 2:3
21 04 3
/
9/ 200 3:4
21 4 8
9/ / 20 5:0
21 04 3
/
9/ 200 6:1
21 4 8
9/ / 20 7:3
21 0
4 3
9/ / 20 8:
21 04 48
/
9/ 200 10:
21 4 0 3
9/ / 20 11:
21 04 1 8
/
9/ 200 12:
21 4 3 3
/
9/ 200 13:4
21 4
8
/
9/ 20 15:
21 04 0 3
/
9/ 200 16:
21 4 1 8
9/ / 20 17:
21 04 3 3
/
9/ 200 18:
21 4 4 8
9/ / 20 20:
21 04 0 3
/2 2
9/ 00 1:
21 4 1 8
/ 2 22
00 :3
4
23 3
:4
8
21
Tim e
Average Temp
Daily Temp Changes
28
27
26
Sept
27
25
Oct
24
26
23
22
25
Min
20
Max
19
Ave
daily AVG of Air Temperature
18
17
Tem p
Temp
21
24
23
16
15
14
22
13
21
9/2
1/
2
9/2 004
3/
2
9/2 004
5/
20
9/2 04
7/
2
9/2 004
9/
2
10 004
/1
/2
10 004
/3
/2
10 004
/5
/2
10 004
/7
/2
10 004
/9
/
10 200
4
/1
1/2
10
0
/ 1 04
3/
10 200
4
/1
5/2
10
0
/ 1 04
7/2
0
10
/ 1 04
9/
10 200
/2
4
1/2
0
10
/ 2 04
3/2
00
4
12
Date
20
2002
Conclusions
• Temperature changes with tides under
stratified conditions
• Daily flux with air temperatures
• September 2004 cooler than previous
years possibly due to storm events
involving rain and high winds leading to
evaporative cooling
LCFRP (5yr ave)
2004
ADCP
Acoustic Doppler Current Profiler
• Measures velocity based on Doppler
shifting of the sound scatter of
particles in the water
• Assumes particles move at same
velocity as the water
• Averages velocities of regularly
spaced depth cells
5
Discharge
• Calculated by integrating the flow across
the section of the river
Q = integral (v dx dz)
10-25-04 Data
CORMP
Cruise#2
Discharge
(ft 3 /s)
45000.00
40000.00
35000.00
30000.00
25000.00
20000.00
15 0 0 0 . 0 0
10 0 0 0 . 0 0
5000.00
9/
1/
9/ 0 4
7
9 / /0 4
13
9 / / 04
19
9 / / 04
25
1 0 / 04
/1
1 0 / 04
/7
10 / 0
/1 4
1 0 3 /0
/1 4
1 0 9 /0
/2 4
1 0 5 /0
/3 4
1/
04
0.00
Coastal Ocean Research and Monitoring Program (CORMP) http://152.20.21.7/stream.php
Cape Fear River Discharge at the Mouth
Conclusions
45000
40000
D is c h a rg e (ft3 /s )
• Uniform velocity with depth
Sept
35000
Oct
30000
25000
• Discharge varies with rain events
20000
15000
• Higher tidal discharge due to base
flow + freshwater inputs
10000
5000
0
1999
2000
2001
2002
2003
2004
Coastal Ocean Research and Monitoring Program (CORMP) http://152.20.21.7/stream.php
6
pH
How Measure pH
• Measure using a pH meter
Why Measure pH
– Fundamental solution property
– Useful in Characterization
– Has direct impact on chemical and biological
properties
• Typical pH: Fresh H2O = 5.5-7.0
Salt H2O = 7.8-8.2
• On the cruises the pH was between 6.45 and
8.06
Cruise 1
Sep-04
0.4
Oct-04
0.35
[H+] (uM)
0.3
10
0.25
01,02,03 Average
0.2
8
0.15
0.1
0
0
5
10
15
Salinity
20
Cruise 2
6
4
2
0.06
0.05
[H+] (uM)
pH
0.05
0
0.04
M18
0.03
M23 M35 M42 M54 M64
HB
Station
0.02
0.01
0
0
5
10
15
20
25
30
35
Salinity
Conclusion
• The differences between the pH:
– Cruise 1 much lower pH than cruise 2 or
earlier data
Conclusion 2
• Salinity and pH were negatively
correlated during cruise 2 and cruise 1
because as the salinity increases high
pH seawater is added to the system
• Why? Rainfall affecting salinity during first
cruise
– Just had rain from hurricane
– Not much rain during October
7
Dissolved Oxygen (DO)
DO Controls
• Biological Controls of DO
• Why Measure DO
– Production from photosynthesis:
– Important marker of biological activity
– Easy measurement, allow for
characterization of H2O type and health
• CO2+ H2O
CH2O+ O2
– Utilization in respiration and oxidation
• CH2+ O2
• How Measure DO
CO2+ H2O
• Physical Controls on DO:
– Measure using YSI
– Salinity, Temp., Dissolved Organic Carbon
(DOC)
• In-Situ, lowered over side of boat
y = -0.0588x + 106.7
2
R = 0.9151
90
80
8
2004 Cruise 1
7
2004 Cruise 2
01,02,03 Average
70
60
(%)
50
40
6
30
20
5
10
0
0
100
200
300
400
500
600
700
800
900
1000
4
DOC (uM C)
Cruise 2
3
100
Percent Oxygen Saturation
DO (mg/L)
Percent Oxygen Saturation
Cruise 1
100
80
2
y = -0.0309x + 89.275
R2 = 0.8296
60
1
40
0
20
M18
0
0
200
400
600
800
1000
1200
1400
M23
M35
M42
M54
M61
HB
Station
DOC (uM C)
Conclusion
• DO is controlled by dissolved organic
carbon content of Cape Fear
– As DOC increases, % saturation decreases
• This is b/c much of the O2 is used up in oxidation of
the added organic matter
Chlorophyll in the Cape Fear
River
8
Importance
Introduction
• Photosynthetic pigment
present in chloroplasts
• Estimate of phytoplankton biomass
CO2 + H2O ↔ (CH2O) + O2
• Structure is a porphyrin
ring, which is the light
absorbing portion
• Taxonomic distinction for algae based on
distribution between different pigments
• In addition, there is a non
polar phytal chain which
anchors it to the cell
membrane.
Methods
• 3 types of chlorophyll: a, b, and c
• Each absorbs different wavelengths of
light
• Obtain water sample
• Pass determined quantity through a filter
• Freeze until further analysis
Questions
8
6
(ug/L)
• Add acetone to extract chl a
Chlorophyll a Concentrations
Is cruise 1 different than cruise 2?
Cruis e 1 Top
4
Cruis e 2 Top
2
0
• Measure fluorescence
HB
m61
m54
m42
m35
m23
m18
8
6
(ug/L)
Chlorophyll Concentration
Site Identification
Cruise 1 Bottom
4
Cruise 2 Bottom
2
0
HB
m61
m54
m42
m35
m23
m18
Site Identification
9
Is there similarity to other years?
8
(ug/L)
6
16
Top Cruise 1
4
Bottom Cruise 1
2
0
HB
Chlorphyll a Concentration
(ug/L)
Chlorophyll a Concentrations
Is the top different than the bottom?
m61
m54
m42
m35
m23
m18
Site Identification
8
14
2001
12
2002
10
2003
8
2004
6
6
4
Top Cruise 2
4
2
BottomCruise 2
0
2
HB
m61
m54
m42
m35
m23
m18
0
HB
m61
m54
m42
m35
m23
m18
Site Identification
Results
Results
• Greater chlorophyll levels measured at depth,
especially for Cruise 1
• Chlorophyll levels appear to be
directly related to turbidity levels
• Top values for Cruise 1 are lower than top for
Cruise 2
• No relation to salinity levels
• Bottom values for Cruise 1 are mostly greater than
bottom for Cruise 2
• No clear correlation with nutrient
levels or light penetration (Kd)
• Data this year generally falls within range of other
years. Although, scatter in data especially at end
members.
Chlorophyll vs. Turbidity
70
Conclusions
• The Cape Fear River is a very dark river, therefore,
expect to see low chlorophyll levels
Turbidity (NTU)
60
50
• Chlorophyll data ranged from 0.88 to 6.80 ug/L. Normal
chlorophyll values for the Cape Fear ranges from 0.7-15
ug/L
40
30
20
• Chlorophyll in the Cape Fear system is directly related to
turbidity
10
0
0
1
2
3
4
5
Chlorophyll a Concentration (ug/L)
6
7
8
• It is suggested that the Cape Fear River has low
chlorophyll levels because it is a light limited system
10
Dissolved Organic Matter (DOM)
Dissolved Organic Carbon
– CDOM: chromophoric dissolved organic matter
– DON: dissolved organic nitrogen
– DOC: dissolved organic carbon
– TDN(total dissolved N) =DON+DIN(dissolved inorganic N)
Instrumentation
Sources of DOC
– River input (0.2*1015g C yr-1)
– Atmospheric deposition (0.09*1015g C yr-1)
– Porewater diffusion (0.02-0.17*1015 g C yr-1)
– Biological production
• Sloppy feeding
• Excretion and cell lysis
• Release from fecal matter
• DOC was measured using the high
temperature catalytic oxidation (HTCO)
method with NDIR detection on a
Shimadzu TOC-5050A carbon analyzer.
• TDN will be calculated as the sum of DIN
and DON, which will be measured with a
linked Shimadzu TOC-5050/Antek 9000N
system.
Cruise 1 DOC
Bottom
1500
(uM)
• Utilized high temperature catalytic
oxidation (HTCO)
Surface
Concentration
Methods
1000
500
0
M18
M23
M35
M42
M54
M61
HB
Station
(uM)
• Chemiluminescent decay
Cruise 2 - DOC
Concentration
– Converts DOC into CO2Æ quantified IR
– Converts TDN Æ NOx + O3Æ NO2*
1000
800
600
400
200
0
Surface
Bottom
M18 M23 M35 M42 M54 M61
HB
Station
11
Cruise 1 - TDN vs. Salinity
Bottom
y = -33.575x + 1172.1
R2 = 0.9678
Linear
(Series3)
500
0
0
10
20
30
40
Salinity
CFRP - DOC vs. Salinity
(uM)
Surface
1000
Concentration
Concentration
(uM)
Cruise 1 - DOC vs. Salinity
1500
Concentration (uM)
R2 = 0.9667
0
2000
y = -27.6x + 1119
R2 = 0.84
1500
y = -1.6826x + 78.81
100
80
60
40
20
0
10
20
30
40
Salinity
1000
Cruise 2: TDN vs. salinity
500
Concentration
(uM)
Cruise 2 - DOC vs. Salinity
5
10
15
20
25
30
35
concentration
0
Salinity
Surface
Bottom
1000
750
500
y = -29.016x + 1141.1
R2 = 0.9633
250
0
0
10
(uM)
0
y = -2.3343x + 93.547
R2 = 0.8618
100
80
60
40
20
0
0
20
10
20
30
40
Salinity
30
Salinity
Conclusions
Nutrient Distribution In the
Lower Cape Fear River
• DOC surface concentrations were
significantly higher than past years
• DOC with respect to salinity showed
conservative mixing, consistent with
historical data
Stephen Gill
MS Marine Science
University of North Carolina at Wilmington
601 South College Road,
Wilmington, NC, 28403
• TDN values were analogous with past
years for lower CFRP
Nutrient assay Process
Long term comparisons.
Nitrite + Nitrate concentration in the Lower Cape Fear River (1997-2004)
500
Continuous Flow
Analysis
Filter
Phosphate
Refrigerate
Nitrate
Ammonium
Nutrient concentration (ug/
450
Surface and Bottom sample
400
350
300
LCFRP 1997-2003
250
UNCW 2003-204
UNCW 2004
200
150
100
50
0
M18
M23
M35
M42
M54
M61
HB
Station
12
Physical Controls - Conservative mixing
Physical Controls - Conservative mixing
Nitrate + Nitrite concentrations with respect to salinity in the lower Cape Fear River.
Phosphate concentrations with respect to Salinity in the Lower Cape Fear River.
40
3.5
35
3
y = -1.3522x + 44.063
25
Oct. surface
Oct. bottom
20
Nov. surface
Nov. bottom
Linear (Nov. surface)
15
10
P concentration (umol/l)
NN concentration (umol/l)
R 2 = 0.9946
30
2.5
Oct. surface
2
Oct. bottom
y = -0.0564x + 1.8996
Nov. surface
R 2 = 0.9968
Nov. bottom
1.5
Linear (Nov. surface)
1
0.5
5
0
0
0
5
10
15
20
25
30
35
0
5
10
15
Salinity
20
25
30
35
Salinity
Physical Controls - Conservative mixing
Cruise 1
Ammonium concentrations with respect to saliniy in the Lower Cape Fear
River
Nutrient concentration in the Lower Cape Fear River (Oct. 2004).
18
P concentration (umol/l
12
10
Oct. surface
8
Oct. bottom
Nov. surface
6
Nov. bottom
4
2
5
10
15
20
25
30
35
14
12
N+N surface
N+N bottom
10
P surface
P bottom
8
A surface
A bottom
6
4
2
M23
M35
M42
M54
M61
HB
Station
Salinity
Conclusions
Cruise 2
• Cruise Averages consistent with long term
data.
Nutrient concentration in the Lower Cape Fear River (Nov 2004).
40
Nutrient concentration (umol/l)
16
0
M18
0
0
Nutrient concentration (umol/l)
14
35
30
N+N surface
25
N+N bottom
P surface
20
P bottom
A surface
15
A bottom
10
• Individual cruises highly variable
(Analogous to seasonality).
• Nutrient distribution explained in terms of
salinity.
5
0
M18
M23
M35
M42
Station
M54
M61
HB
• Nutrient peaks correlate to turbidity
maxima.
13
What are we measuring?
• Photosynthetically active radiation (PAR)
• 400-700nm
• Utilized in photosynthesis by
phytoplankton
Light Attenuation in the
Cape Fear River
Jeremy Pealer
Light Attenuation:
Cape Fear River Estuary
Licor Radiometer
M61 Light Attenuation: Cruise 2
M18 Light Attenuation: Cruise 2
PAR Irradie nce
PAR Irradiance
0
20
40
60
80
100
0
0.0
0
0.5
0.5
1.0
1
1.5
1.5
2.0
Series1
Expon. (Series1)
2.5
Depth (m)
Depth (m)
• Measures PAR at
specified depth
• Compare to surface
PAR to get Kd
• Kd measures light
attenuation rate as a
function of depth
• Increase depth,
decrease PAR
50
2
2.5
3.0
3
3.5
3.5
4.0
4
4.5
4.5
100
Series 1
Expon. (Series 1)
Estuarine Turbidity
What are controls?
Turbidity Trends
• Ez = E0 e-Kd z (where Ez is irradiance at depth z and
Depth
Light is absorbed or scattered
Turbidity
Dissolved organic matter (CDOM)
Turbidity (NTU)
E0 is irradiance just below the surface)
•
•
•
•
50
40
30
20
10
0
Cruise 1
Cruise 2
LCFRP 2003
M18 M23 M35 M42 M54 M61 HB
• Kd = Kd water + Kd turbidity + Kd CDOM
Station
14
Light Attenuation:
The Effects of DOC and Turbidity
Kd Trends in the Estuary
Kd versus DOC
Light Attenuation Coefficients
Kd (1/m)
6
k ( 1 /m )
Cruise 1
4
Cruise 2
2
LCFRP 2003
0
M18 M23 M35 M42 M54 M61
Stations
y = 0.0036x + 2.062
R2 = 0.5519
HB
2004 Cr 1
6
5
2004 Cr 2
4
3
2
1
2001 + 2002
y = 0.0018x + 0.8424
R2 = 0.8268
0
0
200
400
600
800
1000
1200
1400
DOC (µM C)
Kd v e rsus Turbidity
Kd (1/m)
8
8
7
8
7
6
5
4
3
2
1
0
2004 Cr 1
2004 Cr 2
LCFRP av g
y = 0.0604x + 1.1397
2
R = 0.3141
0
20
40
60
80
100
120
140
Turbidity (NTU)
Conclusions
• Kd values similar in Cruise 2 and CFRP
• Estuary turbidity values lower than in
2003
• DOC major contributing factor
• Turbidity minor contributing factor
15