Jb wq poster cerf 2011
1
Analyzing the Trends of Water Quality Indicators Over Time in Jamaica Bay, NY A.L. Lamb 1 , R.B. Boger 2 , and B.F. Branco 1,2,3 1 Department of Earth and Environmental Sciences, The Graduate Center, City University of New York, New York, NY, United States 2 Department of Earth and Environmental Sciences, Brooklyn College (CUNY), Brooklyn, NY, United States 3 Aquatic Research and Environmental Assessment Center, Brooklyn College (CUNY), United States 1 mile 3. The NPS Dataset Dataset begins in 1966, but data set is sparse until 1995. 1995 – 2009: Surface and bottom (when applicable) samples including nitrate, orthophosphate and chlorophyll at 13 stations. Our preliminary analysis only includes these years due to concerns about changes in sampling and analysis protocols Summer values – Memorial Day (late May/early June) to Labor Day (late August/early September) Weekly with some gaps (e.g. due to boat repairs) Chlorophyll and nutrient data prior to 2001 are sparse and not used here During summer of 2011, Lamb participated in sampling and analysis to observe protocols and methods (Fig. 2). 4. The Approach Analyze along hydraulic flow paths (Fig 3). Hydroqual model results indicate a direct flow path from station 3 to station 9A via 5A, 6, and 6B. Transport around the southern channel is slower. Avoid spatial averaging because we want to see internal processes (changes along flow path). Check for interannual trends at individual stations. Check for relationship between precipitation and other variables. 1. Jamaica Bay – The “Sewage Estuary” Four municipal wastewater treatment plants servicing Brooklyn and Queens (Fig. 1) contribute ~90% of the nitrogen load, or approximately 14,000 kg of nitrogen per day (Benotti et al. 2006). Nitrogen reduction programs are being implemented with the goal of reducing WWTP loading by 50%. Restoration of oysters, eelgrass and the disappearing salt marsh islands is underway. 2. The Problem Multiple agencies, for example the New York City Department of Environmental Protection (NYCDEP) and the National Park Service (NPS) collect similar monitoring data, with little time given to coordination and in depth analysis. Data sets are not easily accessible. Timely analysis of data sets may improve management efforts and help identify weaknesses in our understanding of the Jamaica Bay system. We are currently working with the National Park Service to create a georeferenced database of their monitoring data and to conduct an analysis of temporal trends and relationships between water quality parameters. 1994 1996 1998 2000 2002 2004 2006 2008 2010 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50 0.55 0.60 Nitrate (mg/L) JB3 JB5A JB6 JB6B JB9A Increase in nitrate (2001-2009)? STN p-value 9A 0.003 6B 0.004 6 0.008 5A 0.042 3 0.200 1994 1996 1998 2000 2002 2004 2006 2008 2010 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 Secchi Disk (m) JB3 JB5A JB6 JB6B JB9A 1996 – 2009: Significant decrease in Secchi Depth for JB6 (p=0.0007) and JB9A (p=0.007) 1994 1996 1998 2000 2002 2004 2006 2008 2010 16 18 20 22 24 26 28 30 32 Salinity (psu) JB3 JB5A JB6 JB6B JB9A 0 1 2 3 4 5 6 7 0 5 10 15 20 0 1 2 3 4 5 6 7 8 9 0 5 10 15 20 25 30 0 1 2 3 4 5 6 7 8 9 0 5 10 15 20 25 30 35 40 45 0 1 2 3 4 5 6 7 0 5 10 15 20 25 30 35 40 0 1 2 3 4 5 6 7 0 5 10 15 20 25 30 35 40 orthophosphate (µM) nitrate (µM) 2005 N:P = 4.0 orthophosphate (µM) 2009 N:P = 3.7 nitrate (µM) orthophosphate (µM) nitrate (µM) 2008 N:P = 4.3 Along flowpath from East to West, nitrate and ortho- phosphate decrease at a molar ratio of approximately 4 to 5 from 2005 to 2009. Note that ammonia is not measured by NPS, but is included in the NYC DEP monitoring program. orthophosphate (µM) 2007 N:P = 5.1 nitrate (µM) orthophosphate (µM) 2006 N:P = 5.1 nitrate (µM) Acknowledgements: Mark Ringenary of the National Park Service collected all of the data used in this work. We would also like to acknowledge the collaboration with Mark Christiano who was instrumental in starting the effort to compile these data into a user‐friendly database. Also, we thank the many undergraduates at Brooklyn College who have volunteered their time to copy, past, and type data. 0.0 0.2 0.4 0.6 0.8 1.0 0.0 0.2 0.4 0.6 0.8 1.0 2009 2008 2007 2006 2005 Normalized orthophosphate Normalized salinity Mixing line May 20 Jun 3 Jun 17 Jul 1 Jul 15 Jul 29 Aug 12 Aug 26 20 22 24 26 28 30 32 Salinity (ppt) JB3 JB5A JB6 JB6B JB9A May 20 Jun 3 Jun 17 Jul 1 Jul 15 Jul 29 Aug 12 Aug 26 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 JB3 JB5A JB6 JB6B JB9A orthophosphate (mg/L) 0.0 0.2 0.4 0.6 0.8 1.0 0.0 0.2 0.4 0.6 0.8 1.0 5/24/2007 8/15/2007 8/23/2007 Normalized orthophosphate Normalized salinity Mixing Line Figure 1: Jamaica Bay, NY (from Benotti et al. 2006) Figure 2: Annesia Lamb on a sampling trip with the National Park Service in Jamaica Bay during the summer of 2011 Figure 3: NPS water quality monitoring stations in Jamaica Bay. The yellow circles indicate stations included in the below analysis. Hydroqual models suggest strong hydraulic connectivity between these stations. 8. Discussion Results from monitoring programs are often presented in reports of annual Bay‐wide averages. Such averaging (e.g. all sampling stations over an entire season or year) obscures the spatial patterns that inform us of physical controls on water quality. Jamaica Bay (like most estuaries) is defined by strong gradients in salinity in spite of the distribution of WWTP outfalls and Combined Sewer Overflow discharge points. These gradients are important to consider with respect to restoration efforts (oyster, eelgrass, marsh islands). No relationship was found between precipitation and interannual or within summer variations in parameters, including salinity. Variations in WWTP freshwater discharges may be controlling salinity. It is also interesting to note that the influence of the Coney Island WWTP and the 26th Ward WWTP outfalls was not prominent along the hydraulic flow path presented here. 5. Interannual trends Strong east‐west gradients in salinity, nutrients, chlorophyll and Secchi depth persist every year (summer averages). Nitrate appears to be increasing, particularly in easternmost portion of the Bay. The Bay also appears to be getting saltier (perhaps decrease in WWTP discharges) with decreasing light penetration. 6. Nutrient dynamics The depletion of orthophosphate along the flow path appears to be conservative mixing (below). The low N:P ratio of nutrient depletion along the flow path (right) suggests nitrogen limitation during the summer in spite of the high nitrogen loading. However, results should be interpreted with caution because ammonia is not included in NPS measurements, and two WWTPs discharge along the flow path (Fig. 1). 7. Patterns during a typical summer season (2007): The saw tooth pattern for salinity and orthophosphate, particularly for western stations, suggests a strong tidal influence on water quality readings. The orthophosphate exhibits strong conservative behavior on some sampling dates, though this pattern is not seen with nitrate and other parameters. 9. Conclusions The tides appear to be an important driver of water quality variations during summers and need to be considered during the analysis The NPS water quality monitoring should include other forms of nitrogen and phosphorus to allow more detailed analysis of nutrient dynamics The NPS, NYCDEP and other agencies should begin coordinating their monitoring efforts and evaluate the scientific value of their current sampling protocols and methods. orthophosphate appears to behave conservatively in the Bay suggesting that nitrogen is limiting in spite of the high loading rates
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Transcript of Jb wq poster cerf 2011
Analyzing the Trends of Water Quality Indicators Over Time in Jamaica Bay, NYA.L. Lamb1, R.B. Boger2, and B.F. Branco1,2,31Department of Earth and Environmental Sciences, The Graduate Center, City University of New York, New York, NY, United States2Department of Earth and Environmental Sciences, Brooklyn College (CUNY), Brooklyn, NY, United States3Aquatic Research and Environmental Assessment Center, Brooklyn College (CUNY), United States
1 mile
3. The NPS DatasetDataset begins in 1966, but data set is sparse until 1995.1995 – 2009: Surface and bottom (when applicable) samples including nitrate, orthophosphate and chlorophyll at 13 stations.
Our preliminary analysis only includes these years due to concerns about changes in sampling and analysis protocolsSummer values – Memorial Day (late May/early June) to Labor Day (late August/early September)Weekly with some gaps (e.g. due to boat repairs)Chlorophyll and nutrient data prior to 2001 are sparse and not used hereDuring summer of 2011, Lamb participated in sampling and analysis to observe protocols and methods (Fig. 2).
4. The ApproachAnalyze along hydraulic flow paths (Fig 3). Hydroqual model results indicate a direct flow path from station 3 to station 9A via 5A, 6, and 6B. Transport around the southern channel is slower. Avoid spatial averaging because we want to see internal processes (changes along flow path). Check for interannual trends at individual stations. Check for relationship between precipitation and other variables.
1. Jamaica Bay – The “Sewage Estuary”Four municipal wastewater treatment plants servicing Brooklyn and Queens (Fig. 1) contribute ~90% of the nitrogen load, or approximately 14,000 kg of nitrogen per day (Benotti et al. 2006). Nitrogen reduction programs are being implemented with the goal of reducing WWTP loading by 50%. Restoration of oysters, eelgrass and the disappearing salt marsh islands is underway.
2. The ProblemMultiple agencies, for example the New York City Department of Environmental Protection (NYCDEP) and the National Park Service (NPS) collect similar monitoring data, with little time given to coordination and in depth analysis. Data sets are not easily accessible. Timely analysis of data sets may improve management efforts and help identify weaknesses in our understanding of the Jamaica Bay system.
We are currently working with the National Park Service to create a georeferenced database of their monitoring data and to conduct an analysis of temporal trends and relationships between water quality parameters.
1994 1996 1998 2000 2002 2004 2006 2008 2010
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
0.50
0.55
0.60
Nitr
ate
(mg/
L)
JB3 JB5A JB6 JB6B JB9A
Increase in nitrate (2001-2009)?STN p-value9A 0.0036B 0.0046 0.008
5A 0.0423 0.200
1994 1996 1998 2000 2002 2004 2006 2008 20100.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
Secc
hi D
isk
(m)
JB3 JB5A JB6 JB6B JB9A
1996 – 2009: Significant decrease in Secchi Depth for JB6 (p=0.0007) and JB9A (p=0.007)
1994 1996 1998 2000 2002 2004 2006 2008 2010
16
18
20
22
24
26
28
30
32
Salin
ity (p
su)
JB3 JB5A JB6 JB6B JB9A
0 1 2 3 4 5 6 70
5
10
15
20
0 1 2 3 4 5 6 7 8 90
5
10
15
20
25
30
0 1 2 3 4 5 6 7 8 905
1015202530354045
0 1 2 3 4 5 6 705
10152025303540
0 1 2 3 4 5 6 705
10152025303540
orthophosphate (µM)
nitra
te (µ
M)
2005N:P = 4.0
orthophosphate (µM)
2009N:P = 3.7
nitra
te (µ
M)
orthophosphate (µM)
nitr
ate
(µM
)
2008N:P = 4.3
Along flowpath from Eastto West, nitrate and ortho-phosphate decrease at a molarratio of approximately 4 to 5from 2005 to 2009. Note thatammonia is not measured byNPS, but is included in the NYC DEP monitoring program.
orthophosphate (µM)
2007N:P = 5.1
nitra
te (µ
M)
orthophosphate (µM)
2006N:P = 5.1
nitra
te (µ
M)
Acknowledgements: Mark Ringenary of the National Park Service collected all of the data used in this work. We would also like to acknowledge the collaboration with Mark Christiano who was instrumental in starting the effort to compile these data into a user‐friendly database. Also, we thank the many undergraduates at Brooklyn College who have volunteered their time to copy, past, and type data.
0.0 0.2 0.4 0.6 0.8 1.00.0
0.2
0.4
0.6
0.8
1.0 2009 2008 2007 2006 2005
Nor
mal
ized
orth
opho
spha
te
Normalized salinity
Mixing line
May 20 Jun 3 Jun 17 Jul 1 Jul 15 Jul 29 Aug 12 Aug 26
20
22
24
26
28
30
32
Sal
inity
(ppt
)
JB3 JB5A JB6 JB6B JB9A
May 20 Jun 3 Jun 17 Jul 1 Jul 15 Jul 29 Aug 12 Aug 26
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40 JB3 JB5A JB6 JB6B JB9A
orth
opho
spha
te (m
g/L)
0.0 0.2 0.4 0.6 0.8 1.0
0.0
0.2
0.4
0.6
0.8
1.0 5/24/2007 8/15/2007 8/23/2007
Nor
mal
ized
orth
opho
spha
te
Normalized salinity
Mixing Line
Figure 1: Jamaica Bay, NY (from Benotti et al. 2006)
Figure 2: Annesia Lamb on a sampling trip with the National Park Service in Jamaica Bay during the summer of 2011
Figure 3: NPS water quality monitoring stations in Jamaica Bay. The yellow circles indicate stations included in the below analysis. Hydroqual models suggest strong hydraulic connectivity between these stations.
8. DiscussionResults from monitoring programs are often presented in reports of annual Bay‐wide averages. Such averaging (e.g. all sampling stations over an entire season or year) obscures the spatial patterns that inform us of physical controls on water quality. Jamaica Bay (like most estuaries) is defined by strong gradients in salinity in spite of the distribution of WWTP outfalls and Combined Sewer Overflow discharge points. These gradients are important to consider with respect to restoration efforts (oyster, eelgrass, marsh islands). No relationship was found between precipitation and interannual or within summer variations in parameters, including salinity. Variations in WWTP freshwater discharges may be controlling salinity. It is also interesting to note that the influence of the Coney Island WWTP and the 26th Ward WWTP outfalls was not prominent along the hydraulic flow path presented here.
5. Interannual trendsStrong east‐west gradients in salinity, nutrients, chlorophyll and Secchi depth persist every year (summer averages). Nitrate appears to be increasing, particularly in easternmost portion of the Bay. The Bay also appears to be getting saltier (perhaps decrease in WWTP discharges) with decreasing light penetration.
6. Nutrient dynamicsThe depletion of orthophosphate along the flow path appears to be conservative mixing (below). The low N:P ratio of nutrient depletion along the flow path (right) suggests nitrogen limitation during the summer in spite of the high nitrogen loading. However, results should be interpreted with caution because ammonia is not included in NPS measurements, and two WWTPs discharge along the flow path (Fig. 1).
7. Patterns during a typical summer season (2007): The saw tooth pattern for salinity and orthophosphate, particularly for western stations, suggests a strong tidal influence on water quality readings. The orthophosphate exhibits strong conservative behavior on some sampling dates, though this pattern is not seen with nitrate and other parameters.
9. ConclusionsThe tides appear to be an important driver of water quality variations during summers and need to be considered during the analysisThe NPS water quality monitoring should include other forms of nitrogen and phosphorus to allow more detailed analysis of nutrient dynamicsThe NPS, NYCDEP and other agencies should begin coordinating their monitoring efforts and evaluate the scientific value of their current sampling protocols and methods.orthophosphate appears to behave conservatively in the Bay suggesting that nitrogen is limiting in spite of the high loading rates
